BioPhysicochemical Dynamic Computer Model

BioPhysicochemical Dynamic Computer Model
Computer Simulation Model
of
Dynamic BioPhysicochemical
Processes
in Soils
Technical Bulletin 196
Agricultural Experiment Station
The University of Arizona
Tucson
Computer Simulation Model
of
Dynamic Bio- Physicochemical
Processes in Soils
by
Gordon R. Dutt
Marvin J. Shaffer
William J. Moore
Department of Soils, Water and Engineering
Agricultural Experiment Station
University of Arizona, Tucson
Technical Bulletin 196
October 1972
- 3M
Acknowledgments
The authors wish to express appreciation to those who made this Bulletin possible. Outside financial
support was provided by the U. S. Department of the Interior, Bureau of Reclamation under contract
#14 -06 -D -6464 and #14 -06 -D-7057, and to a small extent the IBP Desert Biome #5566 -11.
A special word of thanks is expressed to Mr. John Maletic of the Bureau of Reclamation, whose
encouragement and practical knowledge of the subject was invaluable. Also the authors wish to thank Dr.
Arthur W. Warrick, of the University of Arizona, for his direct help in developing the Moisture Flow Program, and Dr. Thomas C. Tucker of the same University who helped in discussions involving nitrogen
transformations and uptake.
Abstract
A digital computer model was developed to simulate the
effect of certain environmental and managerial factors on
soil-water -plant systems. From an initial state and time
sequential input variables, the model simulates the nonsteady state chemical, physical, and biological changes
occurring in the unsaturated soil matrix and percolating
water.
Processes considered are (1) infiltration and redistribution of soil water; (2) evapotranspiration; (3 ) nitrogen
transformations including hydrolysis of urea -N, immobilization of NH4 + -N, mineralization of organic -N, and
immobilization of NO3 --N; (4) changes in the solute concentration of soil water due to ion exchange, solubility of
gypsum and lime (CaCO3), and dissociation of certain ion
pairs; and (5) nitrogen uptake by crops.
The model predicts with time the distribution and concentration of the constituents considered: i.e., Ca", Mg",
Na +, NH4 +, SO4 -, HCO3 -, Cl -, CO3 -, NO3 -, CaSO4.2H2O.
CaCO3, CO(NH2)2, and organic -N.
The programs and subroutines simulating the above
mentioned processes were verified by comparing predicted
values against experimental results found in the literature or
determined by experiments carried out for verification.
To demonstrate the usefulness of the model, a hypothetical problem of environmental concern was simulated.
Predictions for a period of thirteen years were made to
assess the effect of three levels of N fertilization on the N
content of water reaching the water table. All other factors
were held constant. In the problem considered, only the
highest level of fertilization substantially increased the N
content of the effluent from the soil.
Key Words: Soils, Pollution, Water Quality, Nitrogen,
Microbiology, Water Movement, Systems
Analysis, Fertility, Computer Model.
Table of Contents
ABSTRACT
1
INTRODUCTION
3
THE SYSTEM
3
THE MODEL
4
Mosture Flow Program
Program MOISTRE
Subroutine CONUSE
Subroutine THEDATE and Integer Function DAY
Verification of Moisture Flow Program
5
Biological -Chemical Program
9
Subroutine XCHANGE
Subroutine EQEXCH
Subroutine TRNSFM
Subroutine FL
Subroutine UPTAKE
Miscellaneous Subroutines
Validation of Biological- Chemical Program
APPLICATION TO AN ENVIRONMENTAL PROBLEM
Input Assumptions
Results and Discussion
USER'S MANUAL FOR MODEL
6
7
8
8
11
14
15
23
24
24
24
27
27
27
31
Moisture Flow Program
31
Inputs
Outputs
Restart Capability.
31
32
32
Interface Program
36
Biological- Chemical Program
37
Card Inputs
Tape Inputs
Card Outputs
Tape Outputs
Hints on Program Use
APPENDIX
A. Program Listings
B. Sample Card Inputs
C. Sample Printed Outputs
REFERENCES CITED
38
46
48
49
50
51
51
87
93
100
Introduction
With the current utilization of our water resources,
degradation of water supplies has occurred in many areas.
Increased public awareness of water quality problems has
led to the adoption of legislation designed to stop further
deterioration of surface water and has required that the
impact on the environment be determined for water projects
being planned for the future.
In the past, judgment based on experience and measured
parameters has been used by competent scientists and engineers to estimate the effects of water projects on ecology.
However, too often these judgments have turned out to be
in error, and persons are demanding that judgments in the
future be made on a more quantitative basis.
Among the more complex problems is the prediction
of the effects of irrigated agriculture on water quality. Methods are needed to predict: (1) the short and long term salt
concentration, including salts of nitrogen, in drainage effluent from agricultural areas, (2) the chemical composition
of water moving down into ground water aquifers from
irrigation projects, and (3) the impact on water quality in
an area under study for irrigation.
A promising approach to the above problems is the
development of a conceptual digital computer model of the
dynamic soil -water system. Such a model could be used for
predictions, such as above, and as the basis of a true system
analysis model for predicting management practices which
minimize pollution under economic constraints.
Over the past decade the senior author and colleagues
have addressed themselves to the development of such a
model (20, 21, 23, 24, 25). Like most research, each step
provides the basis for the subsequent work. The foundation
of the model to be reported on was the development of computerized numerical solutions, predicting from initial non equilbrium conditions, the equilibrium solute composition
for soil -water systems at different moisture contents. These
numerical solutions involved more than one chemical reaction (ion exchange of Ca ++ and Mg", and solubility of a
salt, CaSO4.2H2O, (21) ), and were based on thermodynamics, ion exchange equations, and Debye-Hückel theory. This early work was verified at moisture contents much
higher than those encountered under irrigated agriculture,
but was later shown applicable to soil systems in the field
moisture range (22)
Using the above procedures and a finite difference
method, a model was developed to predict the changes in
solute composition in an effluent from a saturated soil during one -dimensional flow (24). Since the chemical reactions considered were limited, the above model was not
applicable to real field situations but the model did demonstrate that such models were feasible. An additional cation,
Na +, and an ion pair, CaSO4 were later added to the model
(23, 20)
The usefulness of activity coefficients and ion pairs in
such calculations has been further substantiated (3, 51),
and the prediction of the solubility of gypsum in the absence
of soil exchangers also has been further evaluated (55).
These early models considered only saturated flow and
chemical reactions which were rapid compared to the rate
of water movement. Also, CaCO3 was not considered and
the analytical data required was too great for most practical
applications under arid and semi -arid field conditions. The
above inadequacies needed to be alleviated.
It was felt that a model of the unsaturated soil zone was
desirable and that such a model should, in addition to the
above, consider the chemistry of nitrogen and additions of
water from rainfall and irrigation, fertilizer, and organic
residue. It should also consider evapotransporation and the
withdrawal of nitrogen by plants. The following work
reports on such a predictive model.
.
.
The System
In developing a conceptual model of the dynamic soilwater -plant system, the "system" must be defined. Consider
a soil in which plants are growing with an underlying water
table (Figure 1) Further, consider a vertical flow line from
the soil surface to the underlying water table. The basic
spacial unit of the "system" is chosen to be one of these flow
lines. The reason for this choice of the "system" is that
.
most equations and methods that are available to consider
moisture content and movement, and chemical changes
occurring in the soil are less complex for one -dimensional
considerations. It should be pointed out, however, that a
3- dimensional flow net may be approximated by joining
1- dimensional sections together.
Page 3
MOISTURE FLOW PROGRAM
BIOLOGICAL - CHEMICAL
-Q -2TABLE
NC
-Q-I-
WATER _
/
PROGRAM
NT
Q'
Q
ROOT ZONE
HORIZONS
NODAL
NUMBERS
CHEMISTRY
SOIL
SEGMENTS
HORIZONS
TEMPERATURE
HORIZONS
ROOT ZONE
HORIZONS
Figure 1. Spacial division of soil-plant water system along a flow line.
The Model
Along a flow line the chemical, biological and physical
properties of a soil rarely, if ever, are homogeneous. To
approximate these field variations and yet to take advantage
of mathematical relationships developed for homogeneous
soil systems, the soil segment concept is employed ( Figure
1) ; i.e., a finite number of equal length units of soil along
the flow lines are considered to be soil segments. Each soil
segment is considered to be homogeneous and the same
segment may or may not be considered to be homogeneous
with its connecting segments.
The authors recognize that the solute composition of
the soil solution effects moisture movement, however, in
this first approximation model it is assumed that these
solute -soil interaction effects on moisture movement are
negligible in comparison with uncertainty that physical and
biological properties effecting water movement can be measured or known.
With the above assumption, it is possible to consider
moisture movement as independent of chemical changes
in the soil solution, hence the problem can be divided into
two parts; first those dealing with moisture movement under
a growing crop, Moisture Flow Program (which is independent of the second), and those dealing with changes in
chemical composition and distribution, Biological -Chemical
Program (which is dependent on the first). To facilitate the
lengthy calculations involved, computer programs written
in Fortran IV (16) were prepared for both of the above
parts. A generalized model diagram is shown in Figure 2.
In execution of the model, the initial moisture contents and
physical properties of the soil (e.g. unsaturated conductivity
and diffusivity relationships) are inputs to the Moisture
Flow Program as well as the amount and time of water
applications (rain or irrigation) and consumptive use data.
From the above input the Moisture Flow Program calculates the moisture content and movement at stipulated time
intervals for each soil segment.
Output from the Moisture Flow Program serves as input
to the Biological -Chemical Program, along with the temperature at various stipulated times and depths and initial
chemical parameters for the solutes being considered in
each soil segment. Also, the amount and time of application
of fertilizer and organic matter residues and the concentrations of solutes in the applied water are inputs to the above
program. The Biological-Chemical Program discussed in
general later calculates the chemical composition of the soil
solution and matrix at stipulated time increments for each
of the soil segments, and the chemical composition of the
water entering the water table.
Page 4
MOISTURE FLOW PROGRAM
INPUTS
=
WATER
APPLICATION &
CONSUMPTIVE USE
MOISTURE FLOW
PROGRAM
DATA
As previously mentioned, the prediction of the behavior
of the soil- water -plant system under field conditions may
be considered as beginning with a description of the moisture regime existing in the soil as a first approximation, if
the effects of ion exchange, solution chemistry, and microbial transformations on moisture movement are regarded as
negligible. The Moisture Flow Program is designed to predict the infiltration, redistribution, plant root extraction, and
drainage of soil water under a growing crop so that these
properties can serve as inputs to models of the chemical and
biological reactions in the "system."
Attempts to describe the moisture regime in the soil plant -water system may be arbitrarily divided into two types
INPUTS = INITIAL
WATER CONTENT &
PHYSICAL PROPERTIES
OF SOIL
1
OUTPUTS = SOIL
MOISTURE CONTENT &
MOVEMENT WITH TIME
INPUTS = FERTILIZER
ORGANIC -N
APPLICATIONS,
TEMPERATURES,
CROP TYPES
&
BIOLOGICAL
CHEMICAL PROGRAM
INPUTS = INITIAL
CHEMICAL AND PHYSICAL
PROPERTIES OF SOIL
OUTPUTS
= WATER,
NITROGEN & SALTS
ENTERING GROUND
WATER
Figure 2. Generalized block diagram of the model.
For purposes of modeling, the basic spacial unit is further subdivided into discrete sections as illustrated in Figure
I. The Moisture Flow Program employs nodes occurring at
equally spaced intervals (OX) numbered downward from
the soil surface to an unfluctuating water table. The first
node is considered to be at the surface. These dimensionless
nodes occur in homogeneous groups of varying numbers
defining soil "horizons," which do not necessarily correspond to morphological soil horizons. Soil "horizon" in this
context merely refers to a zone of soil which is considered
to be homogeneous in certain properties used by the Moisture Flow Program. For the Moisture Flow Program, the
soil physical properties are assumed homogeneous in all
"horizons."
The Biological- Chemical Program utilizes a soil segment concept in which each segment is a length of soil,
spacially defined as the distance along the flow line between
two or more soil nodes having properties which are the
average of nodes contained in that soil segment. A soil
"horizon" in the Biological -Chemical Program is a group
of soil segments initially considered identical with respect
to certain properties, and does not necessarily correspond
to a morphological soil horizon. Each horizon and segment
is assumed to be homogeneous with respect to certain chemical and physical properties. For the Biological -Chemical
Program the physical and chemical properties need not be
homogeneous between horizons. Horizons may be variable
in size (thickness), while segments all have the same size
(OX). Two types of horizons are considered in the Biological- Chemical Program.
(1) Chemistry horizons (corresponding to regions
within the profile which can be assigned separate
sets of soil chemical analysis data).
(2) Temperature horizons (corresponding to regions
within the profile which can be assigned separate
sets of temperature data).
Chemical and temperature data for the horizon in which
the segment falls are assigned to that segment. Segments
which occur across horizon boundaries are assigned data
for the lower horizon (Figure 1). By convention a unit
cross -sectional area of the flow line is always considered
when any system "size" references are made or needed.
Thus, the flow line is considered to have a width of rem,
a breadth of 1 cm, and to extend from the soil surface to
the water table.
depending on whether or not individual roots are modeled.
If the roots are modeled, the approach may be termed
"microscopic," and the moisture flow equation is written
in cylindrical coordinates and solved between the root surface and some radius, r = rmax, from that surface. Boundary
conditions must be specified in terms of head, moisture content, or water flux at the root and r = rmax. Furthermore,
the geometric complexity of the problem increases substantially when more than one root is modeled and two or three
dimensions are considered. To overcome these difficulties,
a single "typical root" is sometimes modeled and its behavior expanded over the entire soil- water-plant root system
by multiplying the average root density (32) .
The second approach to modeling the soil water under
a growing crop ignores moisture flow to individual roots.
"Macroscopic" techniques generally involve the solution of
a finite difference approximation to the moisture flow equation including sink (or negative source) term, S. The equation is usually solved in one -dimension for each depth and
time step utilizing a numerical technique to solve for the
pressure head. In particular, the Thomas tridiagonal matrix
algorithm described by Richtmyer (52) is a rapid numerical
method reported to "accurately" predict the infiltration,
redistribution, and drainage of soil moisture in problems
which ignore removal of soil water by plant roots (30, 35) .
Recently, Molz and Remson (45) have utilized the Douglas Jones predictor- corrector method to solve the moisture flow
equation with a sink term included, but have not considered
the addition and redistribution of water applied to the soil
surface.
Boundary conditions in problems utilizing this macroscopic approach can be specified in meaningful terms, with
the upper boundary simulating the soil surface and its properties of infiltration and evaporation. The lower boundary of
the system can easily be defined to simulate an impermeable
barrier or a water table. Defined in this manner, the macroscopic approach to modeling the system is much more
amenable to two- or three -dimensional models than is the
microscopic technique.
A further advantage of macroscopic techniques is that
they permit the use of many types of sub -models to evaluate
the sink term S, which can vary in complexity depending on
the purpose for which the model is needed. In the most
simple case, the term can be viewed as a function of only
the overall removal rate (volume of water consumed/total
soil profile/unit time) and the depth in the soil ( as fraction
of extraction occurring at each depth) (26, 46). The sink
term model can be expanded to introduce a hypothetical
dependence on the moisture content or pressure head (46),
or can involve any of several techniques which have been
developed to predict the consumptive use of soil water by
Page 5
certain crops under field conditions as functions of variables
such as mean daily temperature, percent daylight hours, etc.,
(5, 26).
It is the purpose of this part of the report to describe
the development of a one -dimensional digital computer program capable of describing the infiltration, redistribution,
drainage, and plant root extraction of soil moisture under a
growing crop. The Moisture Flow Program is designed to
simulate the moisture conditions existing in the field for
periods up to several years in length.
Program MOISTRE is the central part of the Moisture
Flow Program, as shown in Figure 3. Solution to the moisture flow equation, removal of the sink term, S, and calculation of moisture flux all occur within Program MOISTRE.
The soil moisture removal rate by the roots of a growing
crop and evaporation ( "consumptive use ") simulated by the
macroscopic sink term is evaluated in Subroutine CONUSE.
The subroutine utilizes the Blaney -Criddle formula of experimental constants together with the average root distribution
with depth in the profile.
Two additional subroutines, Subroutine THEDATE
( "the date ") and Integer Function DAY, are called from
Program MOISTRE to relate the day number of the simulated run to the calendar date.
PROGRAM MOISTRE
A general form of the moisture flow equation in one dimension can be written
ate =
(D
ax
x
K) -S,
[1]
where 8 is the volumetric moisture content, D is the soil
moisture diffusivity, K is the unsaturated hydraulic conductivity, S is a sink term representing volume of H2O consumed /unit volume of soil/unit time, t is time, and x is
distance measured downward.
(
PROGRAM MOISTRE
&
INPUT DATA
COMPUTE MOISTURE CONTENT AND
FLUX FOR EACH DEPTH NODE AND
TIME STEP
(EACH
DAY)
WRITE ON MAGNETIC TAPE OR
PRINT OUTPUT
e' At
(Bi+1
=Di+1
- Di
-
+
(B,
-1
Bi
+ 9i+i
- 8;_1 -
8i
/2Ax2 -S,
B;_1
2G Kj+
- 2G Ki
-1%
:i)
1
[2]
in which the superscript `i' refers to time, the subscript `j'
refers to depth and G is a gravitational term (G = Ox when
gravity is to be included ) . Initial conditions supplying the
values of 01j, j = 1, Q, where Q is the maximum number
of depth nodes and boundary conditions Bit, and 8'Q define
a set of Q equations with Q unknowns which can be solved
by the Thomas tridiagonal matrix algorithm described by
Richtmyer (52)
The boundary conditions chosen approximate those
existing in the field over a shallow water table. The basal
boundary condition approximating the upper limit of an
unfluctuating water table is
.
8 = constant.
[3]
This condition permits both upward (negative) and downward (positive) flux at the basal boundary.
Three upper boundary conditions are employed at the
soil surface to simulate infiltration, evaporation, or zero
flux. To determine the appropriate condition, the date and
amount of water applications from both irrigation and rainfall are read from data cards. All such applications are
assumed to occur on the first time interval of the appropriate
day. If water has been added but has not entirely entered
the profile, the upper boundary condition is
6
= constant.
[4]
Stating this boundary condition as a moisture content rather
than as a positive pressure head corresponding to the depth
of ponded water is not expected to introduce significant
error. Warrick, Nielson and Biggar (59), using a finite difference solution in terms of pressure head rather than moisture content found the boundary condition expressed in
equation [4] to closely reproduce the infiltration observed
under field conditions on a Panoche clay loam near Fresno,
California.
If both evaporation and plant uptake of soil moisture
are to be simulated by the sink term, S, and no water remains
at the soil surface to infiltrate, a zero flux upper boundary
condition is employed. This restriction can be approximated
START MOISTURE
FLOW PROGRAM
READ CONTROL
A finite difference approximation of equation [1] is
(EACH
HALF -MONTH)
as
SUBROUTINE
COMPUTE CALENDAR
DAY NUMBER
-D
THEDATE
ao
+K=O,x=O.
[5]
DATE FROM
If no crop is growing in the system to be simulated, the sink
term, S, may be set equal to zero and evaporation from the
surface predicted to occur at some rate R by the relationship
SUBROUTINE CONUSE
-D
COMPUTE VALUE OF MACROSCOPIC
SINK TERM
a
+K =- R(R >O,x =O).
[6]
The moisture flux between adjacent nodes is calculated
for each time interval, At, according to the relationship
STOP MO STURE
FLOW PROGRAM
FLUX
Figure 3. Generalized block diagram of Moisture Flow Program.
= [K1 + %= -
-1,i
Di+
1
(
9, +1 +
91
and the flux rate (cm /day) is defined
Page 6
1
- 8; -
20x
83
-1
fit,
[7]
FR =
FLUX
volume of soil/unit time) simulating transpiration, evaporation or evapotranspiration is proportional only to depth
in the soil and an overall extraction rate U (volume of water
consumed /entire soil profile /extended time period). This
overall rate U is assumed to be constant for semi -monthly
periods and may be measured or estimated for various
crops under field conditions.
This technique is perhaps the most simplified method of
approximating the moisture removal rate and is most useful
in cases where the total extraction rate, U, is known to a
sufficient degree of accuracy for the problem under consideration.
The second technique of evaluating the sink term, S,
uses the Blaney -Criddle formula (28) to estimate the total
extraction rate, U, due to crop consumptive use
[8]
At
For each time interval the largest flux rate occurring
between adjacent nodes is used to define the size of the
subsequent time interval. In this way computer expenses
are minimized by defining the time interval as the length of
time required for a certain amount of water to move in the
soil. The defining relationship is taken from Hanks and
Bowers (35)
+1
- 0.035FR'
OX
[9]
where FR' is the largest value of FR occurring in the previous time interval. The size of the time interval is sometimes
reduced so that the Program MOISTRE can write output
values for the Biological- Chemical Program on magnetic
tape at exact 0.1 day intervals, or enable a specified amount
of free water to infiltrate from the soil surface. For cases in
which the flux rate is slow, i.e., FR < 17.5 cm /day, the
time interval is set equal to 0.01 day (14.4 minutes).*
Single-valued relationships for soil moisture diffusivity,
D, and unsaturated hydraulic conductivity, K, as functions
of moisture content, 8, are necessary. For each time interval,
values of D(0) are calculated from an estimate of the moisture content that will exist at the end of the next time interval
as suggested by Hanks and Bowers (35) and averaged over
two depth nodes. The relationship used is
U
- 6; +1) + 0111 + Y(01 -1-
01
-2) +
[10]
2
where Y is a weighting factor defined
Y
= 0.7
+
(
Ati
-1
).
[12]
where U is the volume of water consumed/entire profile/
time period, K is the consumptive use coefficient for a particular crop for the time period, T is the mean temperature in
degrees Fahrenheit, and P is the percent of annual daylight
hours occurring in the time period and 2.54 is the conversion from inches to cm. Values of K, T, and P determined
under field conditions at various locations for many crops
are available for semi -monthly periods (5, 18, 28).
Utilizing either of the two techniques described above
to obtain a numerical value of the total extraction rate, U,
for a given period of time, the value is reduced to a daily
basis and distributed throughout the soil profile in proportion to a constant extraction pattern, such as average
effective root distribution, by the relationship
6; + =i2
Y(Bi +i
- (K) (T) (P) (2.54)/100,
S;
[11]
The conductivity function, K, is also assumed to be constant
over the time interval, but is evaluated on the basis of the
moisture content that exists at the start of the time interval
and averaged over two depth nodes.
Printed output from the Moisure Flow Program summarizes the moisture movement and verifies that the daily
leachate calculated from summing the flux between the lowest two nodes is equal to the leachate calculated by mass
balance considerations.
Output from the Moisture Flow Program to be used as
input to the Biological -Chemical Program ** is written on
magnetic tape at intervals of 0.1 day. This output consists
of the moisture content at each node, the flux at the upper
and lower boundaries, the net flux between adjacent nodes
and the consumptive use at each node for the 0.1 day period.
SUBROUTINE CONUSE
At the present time, the model utilizes two methods of
evaluating the moisture removal rate S. The first of these
assumes that the rate of removal (volume of water /unit
(KP) (DEL)
iN PERIOD)
[I[DAYS
[13]
where Si; is the volume of water consumed/unit volume of
soil/unit time for each depth node (j), KP is the fraction of
total extraction (effective roots) occurring in the foot of soil
in which node J occurs, and DEL is the length AX expressed
in feet.
The values for KP, the percent of total extraction occurring in each successively deeper foot of soil were obtained
from Erie, French, and Harris (28) or may be supplied by
the user as input to the program. This approach assumes
a constant withdrawal pattern; i.e. constant effective root
distribution, and is expected to provide satisfactory estimates for many row crops, perennial crops, perennial native
vegetation, and extraction patterns predicting evaporation
only. Although both techniques of evaluating S assume this
constant extraction pattern, the model could be easily
changed to include extraction patterns varying with time if
feasible models of root growth were available.
At low moisture contents, the value of the moisture
removal term, S, may be reduced to prevent the removal
of soil moisture below some specified moisture content.
This reduction of the sink term at any node simulates the
point below which the roots of the growing crop are unable
to extract soil moisture. If this point is reached at any node
*Limiting the maximum size of the time increment, At...,..., to 0.01 day is expected to adequately compromise the requirements for an
accurate but rapid solution. In certain cases; i.e., for course materials or studies in which the response of the model to At /.ßx2 is more closely
examined, it may be possible to increase the value of atm9 =;mum.
*
*A separate interface program must be used to convert from nodes to segments before the Biological- Chemical Program can use this data.
Page
7
in the profile, the amount of moisture which is predicted
to be extracted but which is "not available" is computed as
"deficit moisture."
The moisture removal term, S, in the moisture flow
equation can have different interpretations depending on
the system which is to be simulated. If the system does not
include a crop growing in the soil, the moisture removal
term can be used in two ways to simulate evaporation from
the soil surface:
(a) The sink term, S, can be assumed to be zero and
evaporation predicted by a flux boundary condition, or
(b) The sink term, S, can be assigned a value and withdrawn from the second depth node (OX below the soil surface) while a zero flux boundary condition is maintained
at the soil surface.
If a growing crop is included in the system to be
modeled, the moisture removal telut can be used in two
similar ways:*
(a) The term S can simulate plant root withdrawal at
each depth node below the soil surface and evaporation can
be predicted by a flux boundary condition or,
(b) The withdrawal term S can simulate the total
evapotranspiration withdrawal by the crop and root distribution can be weighted so that evaporation is simulated
from the uppermost depth nodes while a zero flux upper
boundary condition is maintained.
SUBROUTINE THEDATE AND
INTEGER FUNCTION DAY
Subroutine THEDATE ( "the date ") is called from
Program MOISTRE to calculate the calendar date from the
day number relative to Jan 1. Called on a daily basis, THEDATE is used to determine when Subroutine CONUSE
should be called (first or sixteenth of each month).
Integer Function DAY is a subroutine that returns a
single integer value corresponding to the Julian date from
the calendar date. It performs the converse of Subroutine
THEDATE so that water applications can be scheduled on
the correct day number of the run. For periods up to one
year, the Julian date is the same as the day number.
VERIFICATION OF MOISTURE FLOW PROGRAM
The Moisture Flow Program was designed to predict
the behavior of certain soil moisture properties so that these
properties could serve as inputs to models of the biological,
chemical, and physical processes occurring in the soilwater -plant system. Experimental verification of each soil
moisture property was impossible because of temporal considerations, and partially unnecessary because many of the
theoretical or empirical components of the Moisture Flow
Program had been verified in the literature.
The cumulative infiltration is an important and easily
verified property predicted by the model. Single-valued relationships for unsaturated hydraulic conductivity, K, and
soil moisture diffusivity, D, as functions of moisture content,
0, were obtained from data of Warrick et al, (59) on
Panoche clay loam collected from the Fresno area of California. An additional relationship was defined empirically
to extend these properties over the range from O = 0.07 to
8
= 0.15. The relationships presently being utilized are
K(cm/day)
- 4.7
x 10-5x
D(cm2/day) = 2.7 x 104
for 0.38 > O > 0.36,
D(cm2/day)
for 0.36
=
x
exp(35.80),
[14]
exp(-0.90)
[15]
6.3 x 10-1 x exp(25.30)
> O >15,
D(cm2/day) = 6.2 x 10-4 x [exp(35.80
0.236/0]/02 for 0.15 > 8 > 0.07.
[ 16]
[
17]
Comparisons with field observations of cumulative infiltration made by Warrick et al, (59) on Panoche clay loam at
the University of California Westside Field Station are
shown in Figure 4.
Figure 5 shows calculated changes in the moisture profile occurring when moisture is added to a profile which is
dry at the surface yet saturated at the base due to the presence of an unfluctuating water table at day 166.0. At the
first time interval of day 166, 12.8 cm of water was added
simulating a scheduled irrigation. At 1.66.1 days the moisture front had reached a depth of approximately 25 cm, and
at 166.2 days a depth of 45 cm. By 166.3 days all of the
moisture had infiltrated and the soil surface began to dry
out due to plant consumptive use withdrawal. As the soil
continued to dry, the moisture profile continued to redistribute until at 166.4 days only a diffuse wetting front was
present.
To insure that the Moisture Flow Program was selfconsistent with respect to conservation of mass, a check
was constructed to compare the leachate predicted by summing all flux between the bottom two depth nodes with that
predicted from Leachate = (Moisture added)
(Plant
consumptive use)
(Change in storage). This comparison
showed the Moisture Flow Program to be self-consistent
within 0.17% of the total moisture added.
-
-
BIOLOGICAL- CHEMICAL PROGRAM
The chemistry of soil -water systems is extremely complex and involves principles drawn from many disciplines
of science. Any reasonable chemistry model should incorporate and relate the important chemical reactions and
principles associated with the system as defined. The Biological- Chemical Program combines independently derived
relationships for many important biological and chemical
processes occurring in soil -water systems. Although not all
important processes (e.g. those associated with sulfur and
phosphates) are included in this model, it does include
many processes of interest in soil-water chemistry and
related disciplines.
Research (39) has shown that reactions (transformations) involving nitrogenous species (e.g. organic -N,
NH +4 -N, urea -N, NO -3-N, etc.) are significant in soil water systems. In the areas of pollution control, soil fertility,
and plant nutrition, nitrogen transformations are of great
interest. Various mathematical models describing these
reactions have been developed using reaction kinetics (43,
'`The sink term, S, is not removed from the uppermost depth node in order that the desired flux condition may be maintained at this boundary.
This requirement results in a displacement of the effective root distribution but no error in total withdrawal if the depth of the profile is at
least OX cm greater than the depth of the roots.
Page 8
The kinetic approach was applied here because
reaction times involved in microbial nitrogen transformations are on the order of days or weeks. That is, the reaction
rates and states of the system along the reaction pathway
are of interest to the observer. This model incorporates rate
equations for transformations such as hydrolysis of urea,
mineralization- immobilization of organic -N and NH +4 -N,
nitrification of NH +4 -N and immobilization of NO-3 -N.
In addition to nitrogen transformations, researchers
(23) have found that reactions involving ion exchange,
solution -precipitation of slightly soluble salts, and formation
of undissociated ion pairs are important in soils. Since the
reaction times involved in these processes are on the order
of seconds or minutes (34), equilibria principles have been
used in the derivation of descriptive mathematical relationships (21). Here the reaction times are so rapid that the
observer is interested only in the initial and final states ( e.g.
equilibrium) of the system at a point in space and not in
the states along the reaction pathway. This model uses
equations for the processes mentioned above based on principles of steady state equilibria.
Movement of soluble species (e.g. Ca", Na +, Cl -, etc.)
by water flow has been studied by various researchers (25,
50, 57), and has been shown to be closely interrelated with
chemical processes in the system (24) . However, the
assumption may be made that water flow and content are
independent of chemical processes, but chemical processes
are dependent on water flow and content (24) The mixing
cell concept (42) may be employed together with moisture
flow data to simulate solute dispersion and movement in the
system. Dispersion is defined here as a physical or mechanical (not a chemical) mixing process encompassing two
44, 53).
.
40
Panoche
-
Loam
X-measured at U.C. Westaide Field Stotion
predicted by Moisture Flow Program
30
20
10
00
0.2
O.1
0.3
0.6
0.9
1.0
specific processes. The first is mixing caused by molecular
diffusion. This process is important in soil -water systems
only when water flow rates approach the rates of diffusion,
e.g. when little or no water movement occurs (4). Under
most circumstances, the assumption may be made that the
diffusion process produces negligible effects on the soilwater system. The second process includes mixing due
to tortuosity and /or turbulence associated with the pore
spaces. This important process is simulated by the use of
0
.20 .24 .28 .32 .36
10
.04 .08
CONTENT
.12
.16
.20
IO
166.0->
0.7
time.
0 .04 A8
20
00
Figure 4. Predicted and observed cumulative infiltration with
MOISTURE
.16
0.5
TIME ( day )
MOISTURE CONTENT (cm3/cm3)
.12
0.4
166.1
20
30
30
40
40
50
50
60
60
70
70
80
80
90.
90
100.
100
110
110
120.
120
130.
130
140,
140
150
150
Figure 5. Moisture profile changes as 12.8 cm of water is applied at day 166.0.
Page 9
.
( cm3 /cm3)
4
.
8 .32 .36
mixing cells and moisture flow data at each increment in
time and space. The assumption is made that complete
mixing occurs at each increment. Since flow rates vary while
space and time increments generally are kept constant, the
program produces less mixing at faster flow rates. This
phenomenon has been observed experimentally (24).
Research (38) has indicated that nitrogenous chemical
forms taken up by plants are primarily NO-3 and NH +4.
In most cases nitrate is the predominate of the two forms.
Also, research (28) has shown that nitrogen uptake tends
to be proportional to root distribution. Some evidence exists
(28) which suggests nitrogen uptake may be related to
water uptake.
The program provides the user with two methods for
simulating plant nitrogen uptake. With the first, total
plant -N uptake and root distribution are used to estimate
plant -N uptake from each soil segment /Otime. The user
selects the fraction of nitrogen uptake which is nitrate, the
remainder being ammonium.
The second method involves the use of plant -water
uptake data (e.g. supplied from the Moisture Flow Program). The assumption is made that uptake of nitrate and
ammonium is proportional to water uptake. The proportionality constant must be supplied by the user.
A generalized block diagram of the Biological-Chemical
Program appears in Figure 6. The program consists of
three major control routines (MAIN, EXECUTE, and
COMBINE), four computational subroutines (TRNSFM,
XCHANGE, FL, and UPTAKE), and several miscellaneous subroutines. The program predicts, with time, the concentrations (or masses) of chemical species in an unsaturated soil -water system (along the flow line previously
discussed) . In addition, the model predicts concentrations
(or masses) of chemical species leaving the system (i.e.
leached or removed by plants).
Program execution takes place in the order indicated
in Figure 6. Program MAIN reads in control and input
data, and stores it in forms convenient for program execution. In addition, MAIN may be instructed to print a record
of these inputs. Subroutines EXECUTE and COMBINE
control the execution of the computational subroutines for
each time and depth increment, respectively. Subroutine
EXECUTE makes any fertilizer and /or organic matter
applications to the soil on a daily basis. In addition, soil
temperatures are updated weekly. EXECUTE reads moisture flow data from Program MOISTRE* or uses data read
from cards, and calls Subroutine COMBINE for each time
step within a day. COMBINE, in turn, calls the computational subroutines for each soil segment, sums the predicted
changes in mass returned by these subroutines, and updates
the mass values in storage for each segment. Also, COMBINE prints or writes the various output data as requested.
The mass changes returned to subroutine COMBINE
are computed with respect to the various processes being
modeled (i.e.
nitrogen transformations (TRNSFM),
-
ion exchange and solution -precipitation reactions
(XCHANGE), plant uptake of N (UPTAKE), and water
movement of soluble species (FL) ). All changes for a time
step and any one soil segment are based on the same set of
data. This means that each process is independent over a
time step with respect to availability of component masses.
The assumption is made that the rate of change for each
*Following conversion of data from Tape
5
(START BIOLOGICAL
CHEMICAL PROGRAM
-
PROGRAM MAIN
READ CONTROL AND INPUT DATA
STORE INITIAL
SOIL -CHEM DATA
PRINT CONTROL AND INPUT
DATA (OPTIONAL)
SUBROUTINE EXECUTE
MAKE ANY FERTILIZER AND /OR
ORGANIC MATTER APPLICATIONS
INITIALIZE OR UPDATE SOIL
TEMPERATURES (WEEKLY)
(EACH
DAY)
READ MOISTURE FLOW DATA
FROM MAGNETIC TAPE
EACH TIME
STEP
WITHIN A
DAY)
SUBROUTINE COMBINE
FOR EACH SEGMENT:
CALL EXCHANGE SUBROUTINE
CALL NITROGEN SUBROUTINE
CALL SOLUTE REDISTRIBUTION
SUBROUTINE
CALL PLANT -N UPTAKE SUBROUTINE
SUM CHEMISTRY CHANGES AND
UPDATE VALUES IN STORAGE
PRINT OR WRITE SPECIFIED VALUES
STOP BIOLOGICAL -)
CHEMICAL PROGRAM
Figure 6. Generalized block diagram of Biological- Chemical
Program.
component mass is constant over a time step. In the present
version of the model, ten time steps (increments) per day
are used in making the above assumption except that the
program will increase the number of steps to a user supplied
value for that 0.1 interval if a nitrogen deficiency is detected
in some soil segment. If the assumption is valid, the mass
changes become numerically integrated over time yielding
predicted masses (or concentrations) in each soil segment
for each time step.
SUBROUTINE XCHANGE
The equilibrium subroutine (XCHANGE) considers
chemical reactions in base saturated soils which are known
to effect the solute composition of percolating waters. These
include ion exchange and the solubilization or precipitation
of slightly soluble salts.
To calculate the changes in solute composition due to
these processes as moisture moves from segment to segment
along the flow line (Figure 1), it has been assumed in the
model that the reaction rates of ion exchange, solubilization
or precipitation of slightly soluble salts and dissociation of
soluble ion pairs are much greater than the rates of water
format (Moisture Flow Program output) to Tape 1 format (Biological-Chemical Program input).
Page 10
movement and nitrogen transformations. It is further
assumed that the water entering a segment will equilibrate
with any remaining solution, the slightly soluble salts, and
exchangeable ions on the exchange complex.
This subroutine is designed to predict the equilibrium
solution which would result within the segments under the
assumptions stated in the previous paragraph. A simplified
block diagram of the subroutine is shown in Figure 7. It will
be noted that Subroutine EQEXCH is called on the initial
pass for each of the soil segments considered. As will be
seen later, Subroutine EQEXCH calculates the initial concentrations of exchangeable ions present in each segment.
In essence, as indicated in Figure 7, a method of successive
approximation is utilized to solve the various equations in
Subroutine XCHANGE. The solution is reached when all
the equilibrium constants of the various reactions are
satisfied.
In keeping with the Gibbs phase rule, for every new constituent added to the system, a mathematical relation relating the constituent to other constituents in the system must
be added to the model. Also, there must be one more mathematical relationship than components in the system. The
constituents of Subroutine XCHANGE and their mathematical relationships are discussed below.
if added, or when the solubility product (see below) is
exceeded. An equation relating gypsum to other constituents
in the soil is
CaSO4 x 2H2O
= Ca++ + 50=4 + 2H2O
[18]
This reaction has been considered in an earlier model (21)
The equation for calculating equilibrium concentrations
for equation [18] in soil -water systems from initial concentrations or approximations of the constituent concentrations
.
is
X2+BX+C=O
where X
[19]
= change
in concentration of Ca ++ and S0 =4 to
reach equilibrium,
B
= C'ca + C504.
Here C' is the initial or approximation of the ion concentration indicated by the subscripts, and
C
= C'Ca C's04 - Kv/y22
where Ks0 is the solubility product (2.4 x 10 -5), and 72 is
the divalent activity coefficient (discussed below).
Solubility and Precipitation of Gypsum:
A slightly soluble salt often present or added to soils
CaSO4.2H20. It is considered in the model,
is gypsum,
Undissociated Ca and Mg Sulfate:
The chemistry of undissociated CaSO4 and MgSO4 in
solution is similar, thus they will be discussed together. The
chemical reactions taking place in water are
ENTER
al CALL EQEXCH
CaSO4
:17.
Ca++ + SO-4
[20]
MgSO4
2-7.
Mg++ + 50-4.
[21]
(FIRST TIME)
/
CALCULATE CaCO3 SOLUBILITY CONSTANT AT
These reactions have been considered in previous
models (20, 55 ) and the stoichiometric relationships and
derivation of an equation to calculate the equilibrium concentrations can be found in the above papers. The equation
used in the subroutine under discussion is
SPECIFIED MOISTURE CONTENT
CONSIDER SOLUBILITY REACTION CaSO4
+
Ca ++
SO4
+
x
2H2O=
2H2O
i
CONSIDER UNDISSOCIATED ION PAIR REACTION
=Ca"
CaSO4
+
AX2 + BX + C
SO4
-0
[22]
y
1
CONSIDER THE
2Na+
+
where X
EXCHANGE REACTION
Ca-Rs Ca"
+
2Na -R
i
CONSIDER EXCHANGE REACTION
Mg"
+
Ca -R xCa ++
and Ca ++ or Mg' concentrations to reach equilibrium,
= the change in S0 =4
A
= 722
B
=
Mg -R
+
i
CONSIDER EXCHANGE REACTION
NH4
+
Na -R
xNa+
+
C-
t
ION PAIR
- (KD + y22 Caca
or Mg
+
y22 CSO4)
Here KD is the appropriate dissociation constant, and
NH4 -R
CONSIDER UNDISSOCIATED
MgSO4 x Mg" + SOq
(the divalent activity coefficient), and
REACTION
722
CCa or
Mg
C504
- KD
C'CaSO4 or DIgSO4
When the system contains gypsum, the undissociated
t
CaSO4 becomes a constant
CONSIDER THE SOLUBILITY REACTION
+ H2CO3 =Ca" + 2HCO3
CaCO3
CCas04
RETURN TO COMBINE
IF EQUILIBRIUM
CONSTANTS SATISFIED
- KsI
[23]
KD
Ca -Mg Exchange:
Figure 7. Generalized block diagram of Subroutine XCHANGE.
Page
An equation which has been used earlier [21] for
describing Ca -Mg exchange is incorporated in the model.
11
The equation, the appropriate stoichiometric relationships,
and derivation are presented in the above paper. The equation is
Ay2 +By
concentration of Mg ++ and Ca ++ to
reach equilibrium, and
Here ß
= #(1 - Knig.-ca)
= liter of water /g soil, K
g-ca
constant, and
B
= ß(N'Mg + KM1g -Ca N'Ca)
=
Ca -Mg exchange
+ C'ca
- KMg
Ca
Dissociation of CaCO) in Water:
C'Mg
=0
[25]
change in concentration required to reach
equilibrium from initial or approximated conditions,
= aCa aCO3,
H2CO3
- 4K2cu
D
= N'Na Y% (4 C'Ca + N'Na /3)
+
N'Na
ß)
Na /3
where
=
aCa a2HCO3
It may be shown that
=
K
N'ca
2K2Ca-Na N'Ca C'Na
(2ß N'c.a + C'Na), and
E= N 2 Na C'
ca
C Ca
y1/.a
- K Ca
Na
C2 Na
C
i2
K5"Ki
The exchange reactions involving sodium and ammonium are similar to Ca -Mg exchange. The equations are
the same except the exchange constant Kea-mg is different,
and Na+ and NI-1+4 replace Ca
and Mg'
the equations.
Activity Coefficients:
Debye- Hückel Theory has been utilized in the model
to calculate activity coefficients. Discussions of the theory
can be found in textbooks (34) The equation used to calculate single ion activities is
.
= -.509 z2 µ'A
1
[31]
K2
K'
K Cn2co3
Y21 Y2
Y21 Y2
-
Cca C2HCO3
[32]
where y1 and y2 are the activity coefficients for monovalent
and divalent ions respectively (discussed earlier) and C is
the equilibrium concentration of species indicated by the
subscript.
The stoichiometric relations
Oa
Ca -Mg and Na-NH,, Exchange:
log y;
[30]
aE32co3
B
Na,
(ßNi ca+2CNa)-KCaNaC
2C Na)
+
[29]
where K1 and K2 are the first and second acid dissociation
constants for H2CO3. Provided an equilibrium system is
under a constant pressure of CO2 and activity of an
uncharged species is taken as unity, equation [30] becomes
.
Here y% is a ratio of activity coefficients.
(C'Ca
[28]
+ CaCO3 %Ca" + 2HCO-3,
A
= 4Yvz
[27]
where a is activity of the ion designated by the subscript.
The C0 =3 concentration is a function of the CO2 partial
pressure. HCO -3 is usually the predominant form in which
CO2 occurs in soil -water systems. Thus, it is more convenient to consider the following reaction
K
= the
+ CO -3,
and the thermodynamic solubility product, Ks ", is
Ks,
The Gapon [31] equation was used to describe Na -Ca
exchange. The derivation is similar to that in the literature
[23], but the stoichiometric relations are substituted into
the Gapon equation. The equation for calculating equilibrium conditions is
= -4 K2ca-Na ß2, and
B = 4ß (Y3, + 2K2ca-Na N'ca ß + K2ca-Na C'Na )
Ca"
CaCO3
Ca -Na Exchange:
C
=1
Here n is the total number of ion species present in a soil
solution.
Since all ions considered are monovalent or divalent,
the model considers only these two activity coefficients.
C= Cot N'n1g - Kca aig C'Jlg N'Cca
where X
C, z2;.
1
The dissociation of CaCO3 in water is usually shown as
where N' is an approximation of initial concentration of the
exchangeable ion indicated by the subscript and
AX4 + BX3 + CX2 + DX + E
in question and
i
11
J =V2
[24]
= change in
where y
A
+C =O
where z designates the valence of the ion
Ceti
CHCO3
=C'ca+Z
[33]
= C'nco3 + 2Z
[34]
where C'ca and C'HCO3 are the concentrations before equilibria existed or approximations of the concentrations of
Ca +2 and HCO -3 respectively, and Z is the change in moles
to reach equilibria, may be substituted into Equation [32]
to yield the equation
[26]
+ µ%
Page 12
AZ3
+ BZ2 + CZ + D
= 4.0
B = 4.0(C'r1c03 + C'ca),
A
= 0.0
[35]
C
= C'2H003 +
D
=
4.0 C'ca
C'2Hco3 C'ca
Results and Discussion:
CHCO3
- K'/y21
'Y2
Equations [33], [34], and [35] are used to calculate the
equilibrium concentrations of Ca +2 and HCO -3 when they
are included in the subroutine.
Calculating Changes in CaCO3 Solubility with
Changing Moisture Content in Soils:
In the development of models for predicting the behavior of calcareous soil -water systems, it became necessary to
develop equations which described the reactions of CaCO3
in the soil -water systems at various moisture levels.
These reactions have received the attention of investigators at the USDA Salinity Laboratory (11), who have
considered the soil as a closed system in which the CO2 partial pressure is constant. Also, Dyer (27) found that under
conditions where the partial pressure of CO2 was known,
the reaction of CaCO3 could be described in soil-water
systems.
The above investigators either oversimplified (for some
applications) or required information beyond present data
capabilities. With this in mind the following research was
conducted.
As previously mentioned, if a constituent is to be added
to a system, an expression describing its interaction with
the system must be known if the system is to be described
at equilibrium. A convenient reaction to consider which
fits the above criteria is shown in equation [29].
If it is assumed that at a given moisture content the
H2CO3 concentration is constant at equilibrium (this is
equivalent to assuming a constant CO2 partial pressure at
a constant moisture content) and the usual convention that
the activity of a crystalline solid is unity, equation [30]
becomes
K' = aca.. a2Hco3
[36]
The values of K', equation [36], were calculated for each
of the soils at each moisture content using the procedure
indicated above. It was found that a plot of log M, where M
is the percent moisture, against log K' yielded a nearly linear
relationship (Figure 8) Simple linear regression analysis
was used to determine the equation of the best fit line and
the correlation coefficient, r, and standard deviation, s,
were calculated for each soil.
The values for slopes of the lines, the intercepts, r and s
are given in Table 1 for each soil.
.
TABLE
Soil
1
2
3
4
5
6
Values of the Slope, Intercept, Correlation
Coefficient (r) and Standard Deviation (s)
for the Least Squares Line for each Soil.
1.
Slope
-1.886
-1.627
-1.636
-1.707
-1.645
-1.590
Intercept
r
-4.249
-4.588
-4.419
-4.430
-4.454
-4.606
s
0.999
0.992
0.999
0.998
0.999
0.997
0.001
0.106
0.028
0.044
0.020
0.056
o
It has been pointed out in the literature (47 ) that the
solubility product of CaCO3 in the soil is different from
pure calcite, and also the H2CO3 content would be expected
to vary with different soils and moisture contents. The concentration, C, of Ca ++ and HCO -3 can be determined from
the soil extract, assuming that the activity coefficient, y, can
be calculated by equation [26] then equation [36] can be
used with the concentration from the soil analysis to determine K'.
If the value of K' is determined at several moisture contents it would then seem possible to determine the functional
relationship between K' and moisture content.
a
6
-fsOU
s011
s
a 4
4-SOIL
Log
Experimental Procedures:
SOIL
-4-SOIL
so Ii
I
M
Figure 8. Plot of log K1 vs. log moisture percent.
Calcareous soil samples were collected from the A horizons of six different soil series in Southern Arizona. Sub samples of each of the above were equilibrated overnight in
closed containers at the saturation percentage, 100 percent
moisture and 500 percent moisture and an extract of each
was obtained by suction. The extracts were analyzed for
Ca", Mg", Nat, SO -,}, Cl -, HCO-3, and C0 -3 by the
Soil and Water Testing Laboratory of the University of
Arizona.
The equation of the line including all six soils at all
three moisture levels is
Log K'
= -1.68' Log M -4.46.
[37]
The correlation coefficient for equation [37] was 0.988
and the standard deviation was 0.131. It appears from the
Page 13
data presented here that equation [37] is a useful equation
for predicting the solubility of lime. It is used in the subroutine under discussion here to predict when CaCO3 will
appear and behave in a soil system when CaCO3 was not
originally present.
The points for each of the three moisture levels for each
soil have been connected by lines in Figure 8. It would
appear by observation that a better representation than
equation [37] for any one soil would be parallel lines with
the same slope as the regression equation.
In practice the equation of the line for each soil would
have to be based on a value of K' at a known moisture
content. Thus, based on the value of K', percent moisture
and slope, ( -1.68 for each soil at the saturation percentage), theoretical values of K' for the 100% and 500%
moisture were calculated. The values, theoretical and actual,
of Log K' at all three moisture levels and for all of the six
soils were treated as paired data. It was found that the
correlation coefficient for the predicted values and the point
of reference at the saturation percentage when paired with
the experimentally determined values was 0.991. The standard deviation for the above was 0.111. The correlation
coefficients and standard deviations for the soils at all three
moisture contents are given in Table 2.
TABLE 2. Paired Comparison of Measured and Pre dicted Values of Log K' for each of the Soils*
Soil
1
2
3
4
5
6
r
s
0.999
0.993
0.999
0.998
0.999
0.997
0.002
0.109
0.029
0.044
0.020
0.059
water systems; these are undissociated CaSO4 (20) and
MgSO4 (56). Thus, the total sulfate in solution would be
C304T
= C504 +
CCaSO4
+
Similarly, the total Ca, CCaT, and Mg,
CMgSOç.
CMgT
[38]
would be
CCnT
= Co, + CCaSO4,
[39]
CMg'l'
= CDíg + CMgs04.
[40]
The thermodynamic equilibrium constant, K, for equilibrium between the undissociated species in solution and
the appropriate ions would be
KCaS()4
=
KMgso4
=
ac, aso4
[41]
aras04
aMg asO4
[42]
aMgso4
Combining equations [39] and [41] it is found that
CCaSO4
=
Yso4 Yda CCaT C504
KcaSO4
+
[43]
yCa Ys04 C504
and similarly combining equations [40] and [42] that
Yso4 Yníg CMgT C504
CMgsO4
= K1SgSO4
+
[44]
yMg YS04 CS04
Combining equations [38] [43] and assuming the divalent
activity coefficients (y) are equal it is found that
AX3+BX2+CX+D=0
*K' calculated from saturation extract data.
= C504,
A = Y22 = ( Yca y504) _ ( YMg Yso4 )
B = Y2 [(Kcaso4 + Knígso4) + y2
[45]
where: X
It should be pointed out that the moisture contents of
the above investigation are higher than one encounters in
the field. It is assumed in the subroutine that the same relationships hold in the field moisture range.
(Cníg'r
C
SUBROUTINE EQEXCH
This subroutine calculates exchangeable ion concentration from initial soil analysis. In an earlier model by Dutt
and colleagues (25) describing soil -water systems, an
approximation method was used to calculate the exchangeable Na +, Ca", and Mg". Although this method gives
values which are adequate for many applications, it did not
take into account the interactions of sulfate with cations.
Thus in some cases where sulfate was involved, changes in
ion composition of the soil solution would be predicted when
in fact none could occur. Since the concentrations of these
exchangeable cations are necessary to predict changes in
soil solute composition and reliable analytical methods are
not available to determine all of their values in calcareous
soils, an improved method for their calculation was necessary.
+
= Kcaso4 KMgso4 + 72
[CMgT Kcaso4
(KCaSO4
D
CCaT
=
+
,
- Cso4T) J
+ CraT Kaígs04
KMgs04)
J
-Cso4T Kaígso4 KrasO4.
CSO4T
,
Utilizing the activity coefficient for divalent ions and equations [38], [39], [40], (43), [44] and [45] the concentrations
of Ca ++ and Mg ++ can be calculated. A generalized block
diagram of the subroutine for performing these calculations
is shown in Figure 9. An equation that has long been used
to describe Ca -Mg exchange (20) is
ara
K í NCa
amg
NMg
[46]
where N denotes the concentration of the exchangeable ions
indicated by the subscript. For Na-Ca exchange the Gapon
equation which has been exhaustively tested is
Theory:
Sulfate occurs in basic solutions in more than one form.
In addition to the sulfate ion, there are two forms which
have been shown to be of importance in base saturated soil-
Page 14
aNa
YaCa
_K
2
Nva
Nca
[47]
3
The above data were also treated as paired data. Table
gives the slope, correlation coefficients, and standard
deviations.
ENTER
TABLE 3. Correlation Coefficients (r), Slopes, and
Standard Deviations (s) for the Regression
Lines, Through Calculated and Measured Val ues of Exchangeable Ca", Na +, and Mg".
)
CALCULATE IONIC CONCENTRATIONS OF Ca + +,
Exchangeable Ion
Ca"
Mg ++ AND SO4;
AND CONCENTRATIONS OF
UNDISSOCIATED CaSO4 AND MgSO4 IN SOIL
EXTRACT
CALCULATE EXCHANGEABLE Ca + +,
Mg + +,
Mg++
Na+
RETURN TO
EXCHANGE
and
Mg',
= NNa + Nmg + Nca.
Na+
[48]
Combining equations [46], [47] and [48] it is found that
Nca
=
NT acá K2
K1 anlg
aNa
aca
+ 1).
[49]
Knowing the activity coefficients, the ionic concentrations
for an equilibrium soil extract for Ca', Mg', Na +, and
the total exchangeable bases, the exchangeable Ca ++ can
be calculated using equation 49. The exchangeable Na+
can then be calculated from equation [47], and finally the
exchangeable Mg from equation [48]. For practical calculations, the exchange capacity is taken to be equal to NT.
Ammonium is known to be exchanged with other ions
in soil water systems. An equation that has been used to
describe ammonium exchange is
CNH4
CNa
=K
NNH4
o
0.999
0.999
0.996
1.02
0.953
1.20
0.126
0.082
0.068
SUBROUTINE TRNSFM
Figure 9. Generalized block diagram of Subroutine EQEXCH.
NT
s
The correlation between the observed values and calculated
values indicates the procedure for calculating the exchangeable ions is of use here.
CSUBBOUTINE
Ca',
Slope
Na +,
AND NH4
The total exchangeable, (NT),
would be
r
Nitrogen transformations have been the subject of numerous publications. Researchers (2, 7, 10, 17) have investigated various reaction pathways and mechanisms involved.
The literature contains many data sets relating to these
transformations. A few attempts (40, 43, 44) have been
made to construct mathematical models describing some of
the reactions. As previously indicated, these models have
involved a kinetic approach due to the relatively long reaction times involved. A similar approach involving kinetics
was used to develop the nitrogen transformation subroutine
(TRNSFM) . First, concepts of system analysis were used
to define and limit the system and establish pertinent variables and reaction pathways. Next, rate equations based
on these basic variables were developed using computer
oriented statistical analyses together with other information. Subroutine TRNSFM interconnects the transformation pathways derived from the systems analysis and
[50]
NNa
30
25
a.
The value of K. was found to be from 0.17 to 0.3 for
four California soils (41). Since this is a relatively narrow
range, the average of 0.22 is used in the model. The model
also assumes the concentration of NI-1+4 is negligible compared to NT. Thus equation [50] is used directly to calculate
exchangeable NH +4.
Verification of Subroutine EQEXCH:
The data of Paul, Tanji, and Anderson (49 ) were used
to test the subroutine. Their data include chemical analysis
of extracts and exchangeable ions for five California soil
series (Arbuckle, Hanford, Oakley, Yolo, and Sacramento).
A plot of the measured values for exchangeable Ca',
Mg", and Na+ against calculated values (using the procedure indicated here) is shown in Figure 10.
Page 15
5
10
15
MEASURED EXCNANGE PERCENT
meq.
g.
20
/100
Figure 10. Calculated vs. measured exchange
percent for Ca ++ Mg ++ Nat
25
quantified by the rate equations. The subroutine models
urea hydrolysis, mineralization -immobilization of NH +4 -N
and organic -N, nitrification of NI+4 -N and immobilization
of NO -3 -N as a function of component concentrations,
temperature, C:N ratio, and soil moisture content. The
subroutine solves for net changes in mass for urea -N,
NH4 -N, organic -N, and NO3 -N over a time step for each
soil segment. The independently derived rate equations are
solved simultaneously by a numerical integration procedure
which partitions a time step into successively smaller steps
until nearly identical results are obtained for the mass
changes over the original time step. These predicted mass
changes are then returned to subroutine COMBINE.
Systems Analysis: After a thorough review of the literature,
the system was restricted in scope by establishing certain
limitations and assumptions selected on the following basis.
The minor and /or extremely complex parameters were
excluded but enough important ones were included to allow
field applications of the completed subroutine. Next, the
restricted system was subdivided into various biochemical
and chemical pathways within the soil pertaining to nitrogen. Based on these routes, pertinent inputs and outputs
were designated for the system. Finally, pertinent variables
were established which applied to the transformation pathways.
Limitations and Assumptions: The following limitations
apply to the soil -water system considered by this subroutine.
1. The system is restricted to alkaline soils. Many other
soil reactions concerning nitrogen take place primarily under
acid conditions. This limitation serves to simplify the chemistry but still includes most soils of arid regions.
2. Within the subroutine, only nitrogen transformations
are predicted. The leaching of nitrogen chemical forms is
left to Subroutine FL. Uptake of nitrogen by crops is
excluded from the subroutine ( see Subroutine UPTAKE) .
3. The soil moisture content is limited to a range
bounded approximately by field capacity and permanent
wilting point.
The following basic assumptions were made to further
simplify the system.
1. Gaseous losses of nitrogen are negligible. This
assumption is valid when aerobic conditions exist in the
soil, and urea and ammonia fertilizers are not applied on
or near the land surface (14, 15, 29, 33). The assumption
would not hold in cases such as bog soils where restricted
aeration exists, or in cases where ammonia is easily lost
as a gas.
2. The soil pH remains in the range 7.0 to 8.5. The
effect of hydrogen ion activity on soil nitrogen transformations is approximately constant in this interval (1, 17)
3. Symbiotic and non- symbiotic N fixation and fixation
of NH +4 -N in clay crystal lattices are small in magnitude
by comparison with other nitrogen transformations considered in this subroutine.
4. NO -2 -N does not accumulate in the soil beyond
trace amounts.
5. Fertilizers and other N additions are applied uniformly and thoroughly mixed with the soil.
6. The microbial populations of different soils are
approximately equivalent in their responses to pertinent
parameters associated with N transformations.
7. The chemical composition of the soil (other than
nitrogen species) has little effect on N transformations.
Biochemical and Chemical Pathways: Biochemical and
chemical pathways within the soil are combined to include
.
ORGANIC -N
MINERALIZATIONIMMOBILIZATION
NITRATE -N
IMMOBILIZATION
AMMONIA -N
NITRATE -N
NITRIFICATION
UREA
HYDROLYSIS
UREA-N
t
Figure 11. Biochemical and chemical pathways of Subroutine
TRANSFM.
those nitrogen transformations which are performed biochemically by microorganisms or chemically in non -biological reactions, Figure 11. These pathways are in keeping
with the previously mentioned limitations and assumptions.
They include hydrolysis of urea, nitrification of NH +4 -N,
mineralization -immobilization of NH +4 -N and organic -N,
and immobilization of NO -3 -N. They represent the major
biochemical and chemical nitrogen transformations thought
to occur in the restricted soil system. Other pathways are
assumed to be insignificant by comparison.
Hydrolysis of urea was included because urea is a common N fertilizer added to soils, and hydrolysis is the major
reaction occurring with respect to urea in most soil systems.
Immobilization of NH +4 -N is important since microbes use
NH +4, a common nitrogen type in soils, to form cell
material when organic residues with C:N ratios greater
than about 23 are added to soils (6, 12) . Mineralization
of organic residues is significant at carbon -nitrogen ratios
less than about 23 and had to be included as a transformation pathway. Nitrification of NH +4 -N is the primary means
by which NH +4 -N is transformed to NO_2 -N and NO -3 -N
in soils. It is included as an extremely important pathway.
However, microbes may consume significant amounts of
nitrate when high nitrate and low ammonium concentrations
occur over extended periods of time.
Inputs and Outputs: The basic inputs and outputs of the
subroutine are illustrated in Figure 12. The central box
represents the subroutine, and contains the biochemical and
chemical pathways previously mentioned. The surrounding
boxes represent inputs or outputs as designated by the directions of the arrows. Nitrogen amendments include urea -N,
NH +4 -N, NO -3 -N and organic -N (as organic matter).
These nitrogen forms commonly are added to soils either
by man or animals, or in precipitation. Also, they are forms
which can be handled by the established internal pathways.
Together with temperature, moisture content, and initial
soil conditions with respect to C and N, they form the basis
for inputs to the subroutine.
Page 16
bilization pathway were selected in a similar manner. The
temperature, moisture content, concentration of NO -3 -N
and amount of organic -N were selected as possibilities.
Broadbent (7) has shown these variables to be significant
in association with NO -3 -N immobilization.
NITROGEN
AMMENDMENTS
Data Collection: Keeping in mind the limitations, assumptions, and basic variables associated with the system, a
search of the literature was undertaken to locate useful data.
Data of primary interest were those which could be used to
develop rate equations for urea hydrolysis, immobilization,
mineralization and nitrification. In addition, data were
WATER
SUBROUTINE -4---TRNSFM
INITIAL SOIL
CONDITIONS
-4
--
EMPERATUREH"
NITROGEN
CHANGES
IN SOIL
SEGMENT
Figure 12. Inputs and outputs of Subroutine TRANSFM.
Subroutine outputs are limited to changes in concentrations (or masses) of urea -N, NI-1+4-N, NO -3 -N and
organic -N in a specified segment of the soil/At.
Other parameters such as texture, pH, size or species
of the microbial population, bulk density, and soil aeration
could be included in a future extension of the model. However, they are assumed to be relatively minor factors in the
system as defined.
Selection of Basic Variables: Based on the literature review
and systems analysis a set of basic or working variables was
selected for each transformation pathway. These were
parameters which could be important in the system as
defined. The variables or variable combinations used in the
final equations depended on the extent and type of data in
the literature as well as their statistical significance.
The temperature and the amount of urea -N were
selected as working variables for the urea hydrolysis pathway. Researchers (4, 48) have found that soil moisture
content, pH, and areation have little effect on the hydrolysis
rate. Depth of application would be important only if surface or near surface applications are being considered.
Other parameters are probably important but have not been
thoroughly investigated.
The mineralization and immobilization pathways were
studied together as a unit because they are rather closely
related. The basic variables selected were the concentrations
of organic -N and. NH +4 -N, the temperature, the moisture
content, and the C:N ratio of the organic residue. These
parameters have been found to be important in various
studies (7, 9, 12, 17) and are applicable to the system.
Researchers (10, 37) have found that the temperature,
the amount of NI-1+4-N, the amount of NO -3 -N, the moisture content, and the texture are among the important
parameters associated with the nitrification pathway. They
were chosen as likely nitrification variables for the restricted
soil system. Other possible variables such as pH and soil
areation probably are not significant in this system. The
quality of the variable selections was tested before determining the final form of Subroutine TRNSFM.
Variables tried in connection with the nitrate -N immo-
needed to check the results of model routines and the final
model. These also were obtained from the literature.
Enough useful data were collected to allow the development
of the initial equations.
The data for the equations developed in this study were
obtained from the literature as follows:
Urea hydrolysis (8, 48)
Mineralization- Immobilization (7)
Nitrification data (10, 36)
C: N ratio data (1, 6 )
The data used in this study to verify the output of the
computer model were obtained from the literature as
follows:
Urea-N data (8, 48)
Organic-N data (7 )
NH +4 data (7, 8, 10, 36)
NO -3 -N data (7, 8, 10, 36).
As noted later, some derivation data was included in the
verification data set.
Development of Equations: As previously mentioned most
nitrogen transformations in soils take place too slowly to
be approximated by equilibrium relationships. Therefore,
a kinetic approach was selected to model the pathways.
Each pathway was quantified by a preliminary rate equation
developed using computerized multiple regression analyses
of the data from the literature. The final basic equations
appearing in the computer model were determined by modifying some of the preliminary constants to more closely
approximate the data.
The basic variables used in each regression analysis
were those established from the literature review and the
systems analysis. First, transformations such as logarithms,
multiples, divisions, square roots, exponentials, and various
combinations of these were performed on data for the basic
variables. The transformed and basic data were then correlated with the rates to help determine which variable combinations gave the best linear relationships. The independent
variables so chosen for each transformation pathway were
included in a series of least squares multiple regression
analyses. This provided equations for the planes of best fit
through the data points. Usually many combinations of
respective independent variables were tried before the best
equation for a pathway could be found. Variables which
contributed little to the goodness of fit were deleted from
the final equation.
The basic equation form was as follows:
Y
= C + b1X1 + b2X2 + b3X3 ... bX
[51]
where Y is the transformation rate (dependent variable).
X is a basic transformed parameter (independent
Page 11
variable) .
b is a regression coefficient.
C is a constant (Y intercept).
Statistical parameters such as the F ratio, R2 value, and
standard error of estimate of the dependent variable were
used to help determine which combination of independent
variables gave the best fit for each rate equation (19, 54).
It was not necessary for the independent variables to
be independent with respect to each other. Here, the basic
idea was to find a model not to determine the interdependence of the independent variables. The regression equations were valid even though some of the independent
variables were related.
Urea Hydrolysis Rate Equation: The basic variables considered in the development of the urea equation were the
temperature ( °C) and the urea -N concentration (ug/g
soil) . The independent variables in the final equation were
logro temperature ( °C) and loglo urea -N concentration.
Other potential parameters were excluded for their low r
values and /or lack of contribution to the fit. The rate units
for this and all other rate equations used in the model were
expressed in ug/g soil /day unless otherwise noted.
The constant, coefficients, and statistical parameters
for the urea equation appear in Table 4. The simple correlation coefficients (r) for each independent variable correlated with the rates provided some idea of which variables
would contribute most to the fit of the regression plane.
The respective r values were as follows; r(Var. 1)* = 0.622,
r(Var. 2) = 0.678. The critical r value for 60 degrees of
freedom is 0.250 at the 95 percent level of significance.
However, a high correlation with the rate did not yield the
expected contribution to the fit if the variable was highly
correlated with one or more other independent variables.
The F ratio of 624 caused rejection of the hypothesis
that all the regression coefficients equaled zero. The critical
F ratio for 59 degrees of freedom is 3.14 at the 95 percent
level. *
The R2 value of .723 indicated that 72.3 percent of the
variance of the rate was accounted for by the regression.
The s** for the rate showed that 68 percent of the points
fell within -49.0 ug /g soil /day of the regression plane.
This equation represented the best fit obtainable in a
reasonable length of time using data from the literature
(8, 48).
Mineralization- Immobilization Rate Equation: A single
equation was derived for the net rate of NI+4 -N immobilization or the net rate of organic -N mineralization depending
on the sign. A negative rate indicates a loss of organic
residue (mineralization) . A positive rate shows a gain of
microbial cell material (immobilization). A similar sign
convention is used throughout the model; a positive sign
indicates a gain and a negative sign a loss with respect to
that particular constituent.
The basic parameters used in conjunction with development of the mineralization -immobilization equation are the
temperature ( °C),the organic -N concentration (ug /g soil),
the N11+4-N concentration (ug /g soil), and the C:N ratio
of the organic residue. The final equation contains the
temperature, the organic -N concentration and the loglo
NH +4 -N concentration.
The C:N ratio was excluded from this equation because
a complete set of data was available for only one C:N ratio,
80. However, this important parameter was kept in the
model by multiplying the output of the mineralization
immobilization equation by the output of a linear equation
involving the C:N ratio. For example, the multiplication
factor equals unity at a C:N ratio of 80 and zero at a ratio
of 23. The assumption is made that net immobilization
occurs above 23 and net mineralization occurs below 23.
The net rate at 23 is assumed to equal zero. The relationships for developing the equation were taken from the
literature (l, 6). The final equation form is as follows:
M
= -2.51 +
1.85 x logro C:N ratio
[52]
where M is the multiplication factor.
Since the C:N ratios of organic residues change as
decomposition progresses, a method was developed to predict the C:N ratios with time. The literature showed that
microorganisms release about 30 C atoms from organic
residues for every N atom consumed (1, 12). The N may
come from the organic residue or from NH +4 in the soil
water or on the exchange complex. The C either is released
as CO2 gas or used to produce microbial cell material. The
N may be transformed to NH +4 or used in the production
of cell material.
The initial amount of C in the organic residue is estimated by multiplying the amount of residue by 0.4 (1, 12) .
Likewise, the initial amount of N in the residue is approximated by multiplying the amount of residue by 0.4/C:N
ratio (12) . If the ratio is greater than 23, the amount of
residue carbon remaining after some time interval is approximated by subtracting 30 times the predicted amount of
organic -N immobilized from the amount of residual C
present at the start of the interval (1, 6, 12) . The amount
of residue N is assumed to remain constant. That is, it is
assumed that the microorganisms consume only the NH +4
mineral form of N in this C:N ratio range. The new C:N
ratio is computed by dividing the amount of residue C by
the amount of residue N.
At C:N ratios less than or equal to 23, the residual
amounts of C are computed in the same manner except that
the amount of N mineralized is used as the computation
base. The new amount of residue N is determined by subtracting the amount of N mineralized during the time
interval. In this case the assumption is made that the microorganisms derive N only from the organic residues in this
C:N ratio range. Again the ratio is recomputed by dividing
the amount of residue C by the amount of residue N.
When the amount of organic residue becomes equal to
zero, the ratio is set equal to the average C:N ratio for the
soil (e.g. in the range 5 -15). This allows for mineralization
of dead microbial cells with time.
A listing of the constant, coefficients, and statistical
measure for the mineralization -immobilization equation is
presented in Table 4. Independent variables other than
those included in the final preliminary equation were
rejected because their r values were too low or because they
contributed very little to the regression sum of squares. In
this case the critical R value is 0.40 for 43 degrees of freedom. The F ratio of 38.9 was well above the critical value
of 2.83. The R2 value of 0.740 was quite good. A value
above 0.5 was desirable but not essential in this study as
Note: All remaining critical values refer to the 95% level.
* *Standard error of estimate.
* r(Var. 1) = r value for variable 1 in Table 4 (Urea Hydrolysis Equation).
Page 18
TABLE 4. Variables, Constants, and Statistical Tests for the Urea Hydrolysis and Mineralization -Immobilization Rate
Equations.
UREA HYDROLYSIS EQUATION
C + b1 logro (Temp) + b2 logro (Urea-N)
Urea Hydrolysis Rate (ppm /day)
= 4.13 102
b1=-1.56102
F ratio
C
-1.53
b2
R2
102
s
= 6.24
= 7.23
= 4.90.
101
10 -1
10'
MINERALIZATION-IMMOBILIZATION EQUATION
Mineralization -Immobilization Rate (ppm /day)
= C + b1 Temp. + b2 (Organic-N)
=
b1 =
b2 =
C
b3
=
will be seen later. The s for the rate indicates that 95 percent
of the points fell within ±.490 ppm /day of the equation
plane. The respective r values were as follows: r(Var. 1)*
2) = -0.769, r(Var. 3) = 0.706.
Nitrification Rate Equation: The nitrification equation represents the net transformation of NH +4 -N to N0 -3 -N. This
means that some NO -3 -N to NH +4 -N conversion is allowed
in the model. However, the net result always is assumed to
be the appearance of NO -3 -N. The basic variables used to
develop the equation were the temperature (°C), the concentration of NH +4 -N (ug/g soil), the concentration of
NO -3 -N (ug /g soil), and the soil moisture tension (bars).
The independent variables included in the final preliminary
equation are the temperature times the NH +4 -N concentration, the log10 NI+4 -N concentration and the log10
NO -3 -N concentration. Other basic variables and variable
transformations were excluded because of their low r values
or because they did not contribute significantly to the fit
of the data points. Inclusion of the moisture variable in
some form was attempted at some length, but the contribu-
= -0.585, r(Var.
tions to the R values were very small.
The constant, coefficients and statistical parameters for
the nitrification equation are presented in Table 5. The
critical R value 160 degrees of freedom is 0.226. The F
ratio of 29.1 is above the critical value of 2.67. The R2 of
0.384 is lower than was desirable for this equation. Also the
s of 3.84 is high. The respective r values were as follows:
* r(Var. 1) = 0.544, r(Var. 2) = -0.361, r(Var. 3) =
0.497. The fit was rather poor in that a good equation was
needed for the transformation of N11+4 -N to NO -3 -N. The
basic difficulty may have been a lack of good quality derivation data in the literature (10, 36) . However, this problem
was offset when all the rate equations were combined as
a unit (see page 62).
NO- 3-N Immobilization Rate Equation: The NO- 3 -N immobilization equation quantifies the conversion of NO -3 -N to
8.92
2.16
2.70
3.92
+
b3 log10
10-1
F ratio
10'3
R2
10 -2
s
=
=
=
(NH +4-N)
3.89
7.40
2.45
10'
10 -1
10 -1
10 -1
microbial cell material. As in the case of NH +4-N immobilization, the process is assumed to take place only at C:N
ratios greater than 23. The equation does not allow direct
NO -3 -N formation from organic -N, since this transformation pathway is highly unlikely.
The constant, coefficients, and statistical parameters
for the equation appear in Table 5. The basic variables
used to develop the final equation were the temperature
( °C) /the organic -N concentration2 (ug /g soil), e (temperature ),
and the (temperature x (organic -N concentration
NO -3 -N concentration) ) /organic -N concentration. The
respective values were as follows: r(Var. 1) = 0.418,
r(Var. 2)
-0.282, r(Var. 3) = 0.324. The F ratio of
9.96 is above the critical level of 2.83 for 43 degrees of freedom. The critical level for the r values is 0.401. The r, R2
and s values for the rate were within tolerable limits.
-
_
Method of Solving the Rate Equations: The basic rate equations were each derived independently and had to be solved
as unit or system before any predicted output could be
obtained. The method selected is particularly well suited
to a high speed digital computer.
The basic time interval is passed from Subroutine
COMBINE. This means that the outputs from the rate
equations initially are placed in terms of ug /g soil /At.
A first approximation of the concentration of each nitrogen
species at the end of a time interval is obtained in the
following manner.
1. Each rate equation is solved independently based on
the pertinent concentrations at the start of a basic time
interval (e.g. 0.1 day) .
2. Appropriate additions to or subtractions from the
initial concentrations are made based on the magnitudes
and directions of the rates.
Successive approximations for the concentrations are
made by dividing the time interval passed from COMBINE
(e.g. 0.1 day) into series of smaller and smaller time inter-
*Here reference is being made to variables listed in Table 5.
Page 19
TABLE 5. Variables, Constants, and Statistical Tests for the Nitrification and Nitrate -N Immobilization Rate Equations.
NITRIFICATION EQUATION
=
Nitrification Rate (ppm /day)
C
+ b1 Temp.
(NI-1+4
= 4.64
= 1.62
b2 = 2.38
b3 = -2.51
- N) + b2 log10 (NH - N) + b3 log1° NO -3 - N)
+4
C
10°
F ratio
bl
10-3
R2
10-1
s
= 2.91
= 3.84
= 3.67
10'
10-1
10°
10°
NITRATE -N IMMOBILIZATION EQUATION
NO -3 -N Immobilization Rate (ppm /day)
= C + bi Temp./(organic-N)2 + b2 exp (Temp.) +
b3 (Temp. (organic-N) - (NO-3 - N) )/ (organic-N)
= 0.00
bl = 1.52
b2 = 3.23
b3 = -4.90
F ratio
C
(
INPUT
OP-
AMMONIA -N
SECTION
UREA -N
SECTION
s
10-1
10-1
10-3
Construction and Operation: A generalized block diagram
of Subroutine TRNSFM appears in Figure 13 (a complete
Fortran listing is given in the Appendix) . The subroutine
consists of six primary sections. Each contains several loops
or routines related to the primary function of that section.
The urea -N, organic -N - C:N ratio, NH +4 -N, and NO -3 -N
sections are independent of each other so far as sequence
is concerned. That is, the order in which they are arranged
in the subroutine makes no difference in program operation.
The sequence chosen is based on the order in which the
sections were first studied. Of course the input and convergence-output sections have to appear at the beginning
and end of the subroutine, respectively.
The input section is concerned with establishing basic
constants, and control and input data. Unit conversions are
done to convert amounts in ug /segment to ug /g soil and
moisture tensions in cm of H2O to bars.
The urea -N section includes routines for the initial time
interval length and the initial concentration of urea -N. Also,
the urea hydrolysis rate equation, an expression to compute
the amount of urea -N present at the start of the next time
interval, special logarithmic rate functions at limiting tem-
ORGANIC -N C:N
RATIO SECTION
COMPUTE
NITROGEN
CHANGES
CRETURN TO
COMBINE
R2
10-15
10°
val lengths until the results of one series agree with the
previous series within CONVERG 1 * ug /g soil. That is, the
system converges. The output from one time increment
becomes the input for the next. Usually, division of an
interval into 2 to 64 intervals is sufficient to attain the
desired convergence depending on the magnitude of change
during the interval. The method amounts to a simultaneous
integration of all the rate equations to generate predicted
nitrogen concentrations. The changes in concentration
returned to subroutine COMBINE are computed by subtracting initial from final concentrations for the time interval
required.
ENTER
SECTION
10°
= 9.96
= 4.21
= 4.11
J
Figure 13. Generalized block diagram of Subroutine TRANS
*
Page 20
See User's Manual
peratures and urea -N concentrations, and other control
loops are included in this subroutine section. The computer
passes completely through this section before proceeding to
the next.
The organic-N - C:N ratio section is the most involved
part of the program in that it contains the largest number
of expressions and loops. The initial parts are concerned
with the concentrations of organic -N, NH +4 -N, and NO"3-N
present at the start of a time interval. These data are necessary for the first set of calculations pertaining to an interval.
After this, the data for the remaining smaller time increments are generated entirely by the subroutine.
After establishing the initial C:N ratio and setting some
of the constants according to the C:N ratio range, the program enters the mineralization -immobilization rate equation. The resulting rate is modified according to the C:N
ratio and the limiting temperatures, moistures, and concentrations. Also, certain other control loops are employed
at this point.
Next is the NO -3 -N immobilization rate equation. It is
used at this point so that its results can be used along with
the output from the mineralization -immobilization equation
to calculate the C:N ratio at the start of the next time
interval. Loops concerned with the limiting temperatures,
moistures, and concentrations follow the equation. The
usual control loops are included at this stage.
The C:N ratio is recalculated in the routine which
follows. Separate loops are used for the C:N ratio ranges
greater than 23 and less than or equal to 23. The basic
method of recalculation has already been described.
The last part of the organic -N - C:N ratio section is
concerned with storing the amounts of residue carbon and
nitrogen present at the end of a call and computing the
amount of organic -N present at the start of the next time
increment.
The NI+4 -N section of the program contains the nitrification rate equation along with the appropriate limiting
rate functions and control loops. Again, the last part is concerned with the computation of the amount of NH +4 -N
present at t + 1, where t is time.
The NO -3 -N section is rather short since the appropriate rates have already been calculated. The routine cornputes the amount of NO -3 -N present at t + 1 based on the
initial amount of NO -3 -N and the output from the nitrification and NO -3 -N immobilization equations. If the end of
a time step passed from COMBINE has not been reached,
control is shifted back to the urea -N section for the next
time increment. Otherwise control is passed to the next
section.
The final section of the subroutine consists of the convergence and output routines. The convergence routine
compares the output from one series of time increments
with the output from the previous one. If the two differ by
not more than CONVERG1 ug /g soil, control is passed to
the output area. Otherwise, the number of time intervals is
doubled, the concentrations of the nitrogen species stored,
and control passed to the urea-N routine for another series
of approximations. The output area computes delta values
for changes (ug /At) in urea -N, NH +4 -N, organic-N, and
NO -3 -N. These changes are then returned to Subroutine
COMBINE.
Coefficient Adjustments: After the subroutine was constructed, its predicted output was compared with observed
data. The predicted curves had the proper shape, but some
were displaced to some extent from the observed situation.
This could have been caused by the effects of linearizing
a non -linear system during the regression analysis or by
bias introduced into the derivation data by experimental
errors. However, it indicated that the choice of variables or
terms was approximately correct, but that some coefficients
were slightly in error. These discrepancies were corrected
by changing certain coefficients to more closely fit the
observed curves in general. That is, no attempt was made
to fit each individual soil or run with a separate set of
coefficients. The changes made applied to the entire set of
data. A summary of the coefficient adjustments appears in
Table 6.
Also at this stage the limiting rate functions or expressions were added to the program to account for changes
near limiting values of temperature, moisture and concentration. These were developed by curve fitting with respect
to the observed data. They were necessary because the
regular rate equations tended to "break down" near these
boundaries.
A low temperature correction for each rate was found
to be necessary below about 10 °C. Here the original rates
were multiplied by the output from a logarithmic function
based on the temperature. The rates became equal to zero
at about 4 °C. No upper limits or corrections were necessary
for high temperatures because the equations appeared valid
at most maximum soil temperatures occurring below the
surface.
The moisture correction for tensions below about 10
bars was handled in a manner similar to the temperature
correction. However, the rates were still above zero at 15
bars, the lowest moisture content allowed in the subroutine.
The equations were valid at the upper moisture limit of field
capacity. The corrections applied only to the mineralization immobilization, nitrification, and NO -3 -N immobilization
equations. There was no evidence to suggest a moisture
correction for the urea hydrolysis equation in the range
considered in the study.
The low concentration levels were handled in a slightly
different manner. If a rate equation predicted that a greater
amount of nitrogen would be transformed than was present
at that time (based on rate units of ug/g soil /At), the rate
was set equal to the amount remaining. Then the division
was made by the number of time increments /basic time
interval. This procedure generated a "tailing off" effect near
low concentration levels. The procedure seemed to work
well because the curves kept their observed shapes near
TABLE 6. Summary of Adjustments Made in Regression
Coefficients.
Equation
Urea
Hydrolysis
Mineralization Immobili zation
Nitrification
Nitrate -N
Immobilization
*NC
Page 21
C:N Ratio
1
b2
NC*
NC
b3
<
23
NC
NC
1.60.10°
>
23
NC
NC
7.83.10-1
<
<
<
23
23
23
>
23
= No Change
NC
NC
4.50.10°
8.00.10-4 2.38.10-4 -2.10.10°
NC
NC
NC
NC
NC
NC
concentration boundaries and eventually went to zero due
to rounding errors. Generally, the effect was generated at
levels below about 5 ug /g soil. The urea hydrolysis equation
was a slight exception to the above procedure. Here the rate
was set equal to the amount remaining at rates less than
5 ug /g soil /day. This was necessary because of the very
rapid hydrolysis rate with respect to one day.
The regular equations have good results at concentrations near the maximums expected with normal field applications of nitrogen fertilizers.
4001
120-
-
100 -
80-
OBSERVED
PREDICTED
6040-
Verification:
20-
Typical observed* and predicted curves for urea -N,
organic -N, NH +4 -N, and NO -N concentrations versus
time are presented in Figures 14, 15, 16 and 17, respectively. These and similar plots were used to verify Subroutine TRNSFM for several alkaline soils incubated under
a range of conditions allowed in the model. Sets of observed
and sets of predicted values for each nitrogen species studied
were compared by using a least squares linear regression
analysis to obtain the sample correlation coefficient (r),
the linear regression coefficient (b), the Y-intercept (Yo),
and the s * *. Here the observed and predicted concentrations served as the independent and dependent variables
respectively. A perfect fit for the predicted values would
yield an r value of 1.0, a b value of 1.0, a Yo of 0.0, and
an s of 0.0.
o
10
20
TIME
30
40
50
(DAYS)
Figure 14. Observed and predicted urea -N with time.
140-
--
120-
OBSERVED
PREDICTED
100-,
80-
Urea Nitrogen. A total of 31 pairs of observed and predicted data points yielded the following regression equation
60-
Y
40-
I
IO
I
I
20
TIME
30
(DAYS)
40
50
140
-
100
80
OBSERVED
PREDICTED
60
40
20
0
10
20
30
+ 0.925X,
[53]
The numbers 17.1 and 0.925 refer to the Y-intercept and
the regression coefficient respectively. The r value equaled
0.992 while the s was equal to 17.1. All units were expressed
in ug urea -N /g soil. The maximum urea -N concentration
in this set of verification data was 400 ppm. This concentration was close to the upper limit for urea -N allowed in
the subroutine.
The values for Yo and b indicated the overall predicted
urea -N output was slightly higher than the overall observed
concentrations for the examples used to derive the previous
equation. One possible explanation for this difference would
be an incomplete recovery of urea -N in the laboratory. The
computer model more closely approximated the observed
values for NI+4 -N and NO -3 -N in the same samples. The
r value showed that 98.4 percent of the Y variance was
accounted for by the regression of Y on X. The s of 17.1
meant that 95 percent of the predicted values fell within
±34.2 ppm of the regression line.
Figure 15. Observed and predicted organic-N with time.
120
17.1
where X was an observed urea -N concentration,
Y was a urea -N concentration yielded by this equation
(not by the subroutine) .
20o
=
40
Organic Nitrogen: The following equation was obtained
using 56 pairs of observed and predicted data points:
50
TIME (DAYS)
Y
Figure 16. Observed and predicted NH4 -N with time.
*Approximately 50% of this data was new data not used in the
rate equation derivations.
**Standard error of estimate for the predicted values.
=
11.0 + 0.768X
[54]
Here the observed and predicted values were expressed
in terms of ug organic -N /gm soil. The equation represented
a line which was located above the theoretical line (Yo
0.0, b = 1.0) for organic -N concentrations below about
55 ppm, the point where the lines crossed. The organic -N
data from the literature which were used for purposes of
verification fell in a range from about 15 to 60 ppm. The
Page 22
The r value of 0.972 indicated that 94.5 percent of
the variance in the predicted NO -3 -N concentrations was
accounted for by the regressions. The s of 7.90 showed that
95 percent of the predicted NO -3 -N concentrations compared in this analyses fell within ± 15.8 ppm of the regression line.
140 120 -
OBSERVED
PREDICTED
10080 -
SUBROUTINE FL
60-
The mixing cell has numerous references in the literature
(42) as a means for simulating dispersion of soluble chemical species. Subroutine FL uses mixing cells for each soil
4020-
o
i
i
I
i
IO
20
30
40
TIME
(
DAYS
50
)
Figure 17. Observed and predicted NO3 -N with time.
clustering of points within this range could partially account
for the b value of 0.768 as well as the r value of 0.774.
A wider range of organic -N values probably would improve
both the b and r values.
The s of 6.55 showed that 95 percent of the predicted
points fell within ± 13.1 ppm of the regression line.
Ammonium Nitrogen: A total of 83 pairs of observed and
predicted data points was used to derive the following
regression equation
Y
=
11.7 + 1.05X
[55]
The simple correlation coefficient (r) was 0.969, and the
s was 9.47. The concentrations were expressed in ug
NH +4 -N/g soil.
Here the regression line was slightly above and parallel
to a theoretical line with a slope of 1.0 and a Y-intercept
of 0.0. A possible explanation could be incomplete recovery
of NI+4 -N in the chemical analyses, since the model
appeared to more closely predict the concentrations of
those nitrogen species for which the more reliable analytical
methods were available.
The r value indicated that 93.8 percent of the variance
in the predicted values was accounted for by the regression.
The s showed that 95 percent of the predicted concentrations fell within -!-18.9 ppm of the regression line.
For this case of NH +4 -N, the maximum concentration
considered in this set of verification data was 150 ppm while
the minimum was 0.0 ppm.
Nitrate Nitrogen: The following regression equation was
derived using 86 pairs of observed and predicted data
points:
Y = 5.98 + 0.884X
[56]
The r value was 0.972, and the s for the predicted concentration was 7.90. The units were in terms of ug NO- 3 -N /gm
soil.
The regression line crossed the Y -axis at 5.98 and had
a slope of 0.884. This meant that the regression line fell
slightly above the theoretical line at concentrations below
about 50 ppm and slightly below the line above this concentration.
The maximum NO -3 -N concentration in this set of verification data was about 150 ppm, and the minimum about
2 ppm.
segment. Moisture flow data is used to compute mass inputs,
outputs, and storage changes for each cell. Since the water
table is assumed to have a fixed location, the assumption
is made that solute concentrations in the ground water
immediately adjacent to the last (lowermost) segment
(mixing cell) are the same as those in the last segment at
the end of the previous time step. This assumption is necessary because upward as well as downward movement of
water is being modeled. Surface inputs to the system are
simulated as follows. First the assumption is made that
surface fertilizer additions mix completely with water
applied to the soil. Then the amount of water infiltrating
together with its solute concentrations is treated as an input
to the first segment. In no case may the volume of water
entering a segment over a time step exceed the segment
pore volume or exceed the volume of water contained in
a segment from which flow is taking place. If this situation
occurs, the time steps must be reduced or the segment
increased. Otherwise mass balance may not be maintained
with respect to the system.
Another basic assumption made in Subroutine FL is
that only soluble chemical species are capable of being
moved with the water. Here the various soluble species are
all treated as having the same mobility. However, the concentrations of the soluble species in a segment will change
from one time step to another as a function of the various
chemical and physical processes involved.
Theory of Subroutine FL:
The Moisture Flow Program* provides Subroutine FL
with the volume of water contained in each soil segment
at the end of each time step. In addition, it supplies values
for the volumes of water entering and leaving each segment
during each time step. A positive sign indicates downward
flow while a negative sign designates flow upward.
FL estimates the mass of each soluble species moving
into and from each segment over a time step in the following
manner. The assumption is made that each soluble species
moves freely with the water contained in the segment of
interest. Since upward flow is included, some segments may
receive component masses from two adjacent segments over
a time step. The mass contributions from adjacent segments
for a time step are computed by multiplying solute concentrations (assumed constant for any one segment) by the
appropriate flow volumes. Mass losses from a particular
segment are computed in a similar manner using concentrations and flow volumes from the segment. Since soluble
component mass inputs and outputs are known for each
segment, the net changes in mass can be computed from
*Following data conversion of the interfacing program (INTFACE).
Page 23
mass balance considerations. With the assumption of complete mixing, new concentrations may be computed for
consideration over the next consecutive time interval by
dividing soluble component masses by the volumes contained in the respective segments. The same set of solute
concentrations is used for any one time step.
SUBROUTINE UPTAKE
NO -3 and NH +4 are primary forms of nitrogen taken
up by plants (38, 39 ) Nitrogen uptake has been shown to
be directly proportional to root density, (i.e. root mass per
unit volume of soil) The subroutine uses data for total plant
uptake of nitrogen, root distribution with depth, and uptake
distribution between NO -3 -N and NH +4 -N to compute
NO -3 -N and NH +4 -N uptake for each soil segment and each
time interval. The assumption is made that the plant root
distribution is independent of time.
Data for total plant uptake of nitrogen with time either
may be read into the program or computed by Subroutine
UPTAKE. The latter method is based on the assumption
that N uptake is proportional to consumptive use. In this
case, the user must supply the proportionality constant.
Consumptive use data is supplied by the Moisture Flow
Program.
Values for NO -3 -N and NH +4 -N uptake from each segment are computed by one of the two following methods.
(1) Total N uptake is multiplied by the fraction of roots
in the segment and the fraction of uptake as NO -3 -N or
NH +4-N, respectively if plant uptake data is read in, or
(2) consumptive use for each segment is multiplied by the
respective NH +4 -N or NO -3 -N concentrations and combined proportionality constants if the consumptive use
method is selected.
.
.
MISCELLANEOUS SUBROUTINES
Subroutine PRNT: This subroutine prints control and /or
input data. Print options are provided to allow printing
control by the user.
Subroutine MCHECK: This subroutine computes the nitrogen mass balance status (i.e. inputs -outputs vs. delta storage) of the system. The subroutine may be called at various
intervals during program execution. Any discrepancies in
mass balance indicate that time intervals which are too large
are being used or that moisture flow exceeds pore volume
or current pore content. A detailed mass balance report is
printed after each call.
Subroutine TEMP: TEMP reads weekly soil temperature
data for the temperature horizons and assigns these data to
the proper soil segments.
Subroutine CHK: This subroutine examines mass changes
due to nitrogen transformations, and ion exchange and
solution chemistry to determine if Subroutines TRNSFM
and XCHANGE, respectively should be called for the particular soil segment and time interval. The criteria for making these decisions are read into the program as constants.
Subroutine OUTPUT: This subroutine writes on Tape 2
predicted values of the delta and cumulative amounts
leached for the components listed below. The user supplies
the write interval in days. Delta amounts correspond to the
write interval.
1.
Volume of water*
2. NO -3 -N
6. Na+
7. Mg"
3.
NH +4-N
4. Urea -N
5. Ca"
8.
HCO-3
9. Cl10.
CO-3
*Units in cc
All remaining units in µg.
Subroutine UNITSI: This subroutine converts units from
meq /1 to ug /soil segment and from ug/soil segment to
meq/1. Organic matter units are converted from ug /gm
soil to ug /soil segment and vice versa.
Subroutine THEDATE.: This subroutine and Subroutine
DAY compute the date from the day number of the run.
The date is expressed as an integer number (e.g. March 21
would be expressed as a 21) .
Subroutine IDA Y: This subroutine together with Subroutine
DAY computes the day number of the run from the calendar
date, the reference month, and the reference day.
VALIDATION OF THE
BIOLOGICAL-CHEMICAL PROGRAM
In anticipation of the development of the model presented here, a field lysimeter study was established at
Fresno, California. Details of the experimental procedures
have been discussed elsewhere (58). Two sets of lysimeters
were chosen to verify the program discussed in this section.
They were lysimeters 2 and 3 which contained a Panoche
clay loam soil, and lysimeters 5 and 6 which contained
Panoche fine sandy loam. The first set was fertilized with
NH4SO4 and the second set with KNO3.
Soil moisture contents in the lysimeters varied from
those which were predicted to occur under field conditions,
and techniques of estimating crop consumptive use were
found to be inadequate to predict plant root withdrawal of
soil moisture in these lysimeters. To predict moisture contents and moisture fluxes in the lysimeters so that these
properties could serve as inputs to verify the Biological Chemical Program, a simplified moisture predicting program was developed. This program, which has been discussed elsewhere (26), was capable of satisfactorily matching soil moisture tensions throughout the growing season.
The mechanisms used to match these experimentally measured tensions included adjusting effective root distribution,
adjusting Blaney-Criddle crop consumptive use constants,
and adjusting the tension of an imaginary node above the
soil surface to approximate evaporation. Predicted and
observed soil moisture tensions for lysimeter 2 are shown at
two depths in Figure 18 under a growing barley crop.
Observed and predicted values for uptake of nitrogen
by the barley and milo appear in Table 7. The predicted
values for barley are slightly high, while those for milo are
low. The uptake constant of 4 for barley (see Subroutine
UPTAKE) yields reasonable estimates of plant uptake of N.
However, the much higher uptake constant of 40 for milo
still gives a significant underestimate. The low amounts of
NO -3 present in the soil water system could account for
this discrepancy. Probably, the milo is also using NH% as
a source of N.
It would appear from the data presented here that Subroutine UPTAKE yields at best, crude approximations by
application of consumptive use and uptake constants. Since
the nitrogen removal by plants is the most important mechanism of nitrogen removal from irrigated soils, further work
should be initiated to develop a better subroutine. Until
this is done, it is recommended that data on nitrogen uptake
Page 24
TABLE 7. Nitrogen Uptake (g) by Barley and Milo.
Soil
Type
Panoche
CL
Panoche
FSL
Panoche
CL
Fertilizer
Crops
Lys
Straw
Grain
Roots
(NH4)2SO4
Barley
2
.35
.34
.43
.38
.28
.38
.94
1.00
1.14
1.12
.77
.67
.53
.53
.65
.57
.42
.57
3
KNO:
(NH4)2SO4
Barley
5
Milo
6
2
3
by plants be read into Subroutine UPTAKE as inputs. Substantial uptake data are available in the literature (28, 38).
Near the end of 1969, lysimeter 3 was dismantled and
soil samples from several depths analyzed for organic -N.
The results of this analysis together with predicted values
from the model appear in Tables 8. According to the model
an increase in organic -N occurred near the surface. The
TABLE 8. Predicted and observed final organic -N distribution in lysimeter 3 after one year.
Depth (cm)
0- 15
15- 30
30- 45
45- 60
60- 75
75 -105
105 -120
120-135
135 -150
150 -165
165 -180
Observed
Organic -N (ppm)
Predicted
Organic -N (ppm)
358.0
310.0
288.0
353.0
281.0
176.0
178.0
127.0
134.6
124.0
148.0
332.5
334.3
330.4
328.7
324.0
144.5
144.3
144.2
144.6
147.4
147.6
Total
Observed
Total
Predicted
1.82
1.87
2.20
2.20
2.24
2.24
.86
.86
2.22
2.07
1.47
1.62
same phenomenon was observed in lysimeter 3. Data pairing
of predicted and observed organic-N concentrations with
depth yielded a correlation coefficient of 0.954. The slope
of the regression line was 0.986, while the Standard Error
of Estimate was 27.6 ppm.
The predicted and observed total nitrogen concentrations in the leachates, as a function of time, were similar for
each of the various lysimeters. For brevity only the results
for one of the lysimeters will be given here. A plot of the
predicted and observed total nitrogen in the leachate with
time is shown in Figure 19 for lysimeter number 2.
The scatter exhibited by the observed data points may
be due to sampling errors or errors in the chemical analysis.
Note that the predicted curves pass through the observed
scatter of points. The conclusion may be made that the
predictions are within the experimental error of the measured values.
No attempt was made to verify the salt content predicted
by the model. However other work (24, 25) has shown
that the approach used here should yield reasonable results.
It should be pointed out that there are astronomical
possible combinations of factors which could change the
nitrate content, and the results verified, only represent a
small finite number. Thus one can only conclude that to
date the program seems to do an adequate job for the
purpose intended. This does not mean that future verification will not show inadequacies in the Biological-Chemical
Program that are not recognized at this writing.
Page 25
180
180-
160
160-
140
140-
120
20-
100-I
100 --
>-
a
a
80-
80
DEPTH
60
-
=
DEPTH
37cm.
60-
Observed
-
Predicted
40
40-
20
20-
=
73 cm.
Observed
Predicted
i
t
0
0
f
1
+50 0
-200
-400
-600
1
-800 +50 0
TENSION (CM OF WATER)
1
1
Figure 18. Observed and predicted soil moisture tension for lysimeter 2 at 37 and 73 cm. depth.
Page 26
1
-200
-400
-600
TENSION (CM OF WATER)
604428e..,
I2
..
a
0
'
1
20
10
40
30
'
I
50
i
60
70
80
90
100
110
60-
á 44z
28.
1
J
.
0
120
130
140
150
160
170
240
250
260
270
280
290
180
190
, 260
210
220
230
60442812-
0
300
310
320
330
340
DAYS
Figure 19. Observed and predicted NO3 -N concentration in efftuent from lysimeter 2.
Application To An
Environmental Problem
Currently there is concern on the effect of irrigated
agriculture on the quality of percolating water (39, 58, 60)
Questions such as how N fertilizers affect the N content of
effluent leaving agriculture are being asked. It is clear that
many soil and climatic factors and management practices
would affect the above. Since the model presented here was
designed to account for the various factors and practices,
and since it is possible in the model to single out and change
one or more conditions while holding others constant, one
may assess, for example, the effect of different fertilizer
practices. To demonstrate the usefulness of theoretical calculations, it was decided to consider the case where three
different levels of nitrogen fertilizers were used under identical climate and soil factors, and under the same management
practices.
.
INPUT ASSUMPTIONS
The soil parameters and climatic data listed above were
field data collected by the U.S. Bureau of Reclamation.
It was assumed that the soil in an area of interest is a
Panoche loam and that its properties were those given in
Tables 9 and 10. Further, it is assumed that the mois-
ture application data and other management practices are
repeated annually, Table 11 thru 14. The plant uptake and
consumptive use data was also collected by the Bureau of
Reclamation and was considered to be representative of
the area. The 108 lb N acre ( "Normal ") fertilizer application (Table 12) and other management practices were felt
to be typical of those currently in use in the San Joaquin
Valley of California. The imposed moisture and nitrogen
removal pattern by the crop are assumed to be those given
in Tables 15 and 16. The temperature at several depths is
given in Table 17.
RESULTS AND DISCUSSION
As mentioned in the previous section, all of the above
mentioned annual data were assumed to repeat annually for
the calculations when used with the Biological-Chemical
Program. It should be pointed out that this assumption was
not required to perform calculations, but was used to reduce
computer time. The calculations were made over varying
increments of time to allow examination of the generated
values. The total time required by a Control Data 6400
computer including restart time was 32/3 hours.
Page 27
TABLE 9. Initial Soil Analysis.
Chemistry
Horizon
No.
Exch.
Cap.
Gypsum
(meq/ 100 gm soil)
Depth
(cm)
0- 30
30- 61
61- 92
92 -122
122 -152
1
2
3
4
5
27.4
29.5
30.0
31.2
88.8
32.5
34.8
35.3
35.4
39.0
C:N
Bulk
Density
Org.
Mat.
(ug /gm soil)
Ratio
of O.M.
CAL
(lime)
1.3
1.3
1.3
1.3
1.3
2135
1585
1278
1175
1132
5.0
5.0
5.0
5.0
5.0
1.0
1.0
1.0
1.0
1.0
TABLE 10. Initial Soil Analysis of 1:1 Soil Extract.
(meq/l)
Chemistry
Horizon
No.
Depth
(cm)
0- 30
31- 61
61- 92
I
2
3
92-122
122-152
4
5
*NH +4
NO-3
Urea
Ca ++
Na+
Mg++
HCO-3
0.029
0.015
0.011
0.012
0.013
0.60
0.00
0.00
0.00
0.00
0.00
11.9
10.0
12.5
18.3
31.7
53.4
76.5
84.8
103.7
2.2
2.3
1.5
2.0
2.2
3.8
1.8
1.7
5.5
1.1
1.06
1.52
1.58
4.16
24.2
Cl
CO -3
SO =4
0.1
0.1
37.1
6.3
10.2
18.3
52.6
71.1
75.0
89.4
0.0
0.0
0.0
30.2
42.9
*Estimated from total NH +4
TABLE 12. Fertilizer Applications.
TABLE 11. Moisture Application Data.
Application
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Date
Month
Day
(cm)
(in)
01
01
01
06
02
02
02
03
03
03
04
05
06
07
07
08
09
06
0.61
0.30
0.91
0.91
3.35
0.61
0.61
7.62
0.30
4.88
8.84
12.80
7.92
7.92
11.58
6.1
5.18
0.30
0.61
0.91
0.61
0.61
84.09
0.24
0.12
0.36
0.36
10
19
11
11
20
21
22
12
12
12
Day
No.
Amount
15
21
15
21
06
15
21
15
15
15
01
15
10
15
15
06
21
01
06
21
Total
Amount applied (lbs N /acre)
Type
Half
Type*
R
I
R
R
1.32
I
0.24
0.24
3.00
0.12
R
R
1.92
3.48
5.0
3.12
3.12
4.56
2.64
2.04
0.12
0.24
0.36
0.24
0.24
33.12
I
74
UREA
105
135
166
196
NH4
NH4
NH4
NH4
NH4
NH4
222
258
6.79
2.14
8.24
5.95
8.24
4.13
4.90
40.4
I
Double
Normal
13.6
27.2
8.56
33.0
23.8
33.0
4.28
16.5
11.9
16.5
16.5
19.6
8.26
9.80
80.8
162.0
R
I
I
TABLE 13. Organic -N Applications.
I
I
I
I
Day
No.
C:N Ratio
I
R
R
227
30
Amount Applied (lbs N /acre)
Half
Normal
Double
26.7
26.7
26.7
I
R
R
TABLE 14. irrigation Water Analysis (ppm).
*R denotes rainfall or precipitation as the water source, while
I denotes irrigation.
NH+4 NO-3 Ca++
Page 28
0.05
Na+ Mg++ HCO-3
0.10 19.4 37.4 10.5
79.9
Cl-
CO-3 SO-4
48.6 0.60 36.5
TABLE 15. Evapotranspiration Data.
Period
No.
1
2
Month
Dates
01
01
16 -31
02
02
03
03
04
04
05
05
06
06
07
07
08
08
09
09
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
10
10
20
21
11
11
22
23
24
12
12
1
1
Evapotranspiration
(cm)
(in)
0.20
0.20
0.28
0.28
0.81
0.81
-15
-14
15 -28
1
-15
16 -31
1
-15
1.78
1.78
16 -30
-15
16 -31
1 -15
16 -30
1 -15
16 -31
1 -15
16 -31
1 -15
16 -30
1 -15
16 -31
1 -15
16 -30
1 -15
16 -31
4.06
4.09
5.89
6.17
1
Total*
TABLE 17. Weekly Temperature Data.
8.89
9.40
6.86
5.08
2.79
2.54
0.02
0.02
0.08
0.08
0.10
0.10
62.31
Temperature Horizon Depths (cm)
0 -20
0.08
0.08
0.11
0.11
0.32
0.32
0.70
0.70
Week No.
1
2
3
4
5
6
7
1.60
1.61
8
2.32
2.43
3.50
3.70
2.70
2.00
9
10
11
12
13
14
15
1.10
1.00
0.01
16
0.0I
17
18
19
0.03
0.03
0.04
0.04
24.54
*Total amount of the inclusive dates shown under period column.
TABLE 16. Plant Uptake of Nitrogen.
Month
Jan.
Feb.
March
April
May
June
July
August
Sept.
Oct.
Nov.
Dec.
Uptake (lbs N /acre)
0.30
0.30
0.45
0.45
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
1.30
1.30
35
36
37
38
39
2,80
2.80
6.40
6.40
9,20
9.60
14.0
14.6
10.0
8.6
4.3
4.0
0.10
0.00
0.10
0.10
0.20
0.10
40
41
42
43
44
45
46
47
48
49
50
51
52
53
Page 29
20 -46
46 -152
Temperatures ( °C)
8.9
8.9
8.9
8.9
10.0
10.0
10.0
10.0
12.2
12.2
12.2
12.2
12.2
15.6
15.6
15.6
15.6
18.9
18.9
18.9
18.9
10.0
10.0
10.0
10.0
11.1
11.1
11.1
11.1
12.8
12.8
12.8
12.8
12.8
16.1
16.1
16.1
16.1
18.9
18.9
18.9
18.9
22.2
22.2
22.2
22.2
22.2
24.4
24.4
24.4
24.4
23.3
23.3
23.3
23.3
23.3
21.1
21.1
21.1
21.1
20.6
20.6
20.6
20.6
20.6
22.8
22.8
22.8
22.8
22.2
22.2
22.2
22.2
22.2
21.1
21.1
21.1
16.7
16.7
16.7
16.7
12.2
12.2
12.2
12.2
12.2
10.0
10.0
10.0
10.0
10.0
21.1
17.8
17.8
17.8
17.8
14.4
14.4
14.4
14.4
14.4
11.7
11.7
11.7
11.7
11.7
16.7
16.7
16.7
16.7
15.6
15.6
15.6
15.6
16.7
16.7
16.7
16.7
16.7
17.8
17.8
17.8
17.8
18.9
18.9
18.9
18.9
20.1
20.1
20.1
20.1
20.1
21.7
21.7
21.7
21.7
22.2
22.2
22.2
22.2
22.2
21.1
21.1
21.1
21.1
20.1
20.1
20.1
20.1
18.9
18.9
18.9
18.9
18.9
17.8
17.8
17.8
17.8
17.8
2.75
Water Movement: Theoretical values as calculated by Program MOISTRE for moisture flow to and from the water
table over a one year period are shown in Figure 20.
In addition the theoretical moisture content at each
node and the moisture movement between nodes were calculated and stored on tape for use with the BiologicalChemical Program. The above data were too voluminous
to present here.
Nitrogen in effluent: The predicted nitrogen concentrations
in water moving into the water table for the three levels of
fertilization are shown in Figure 21. The initial and final
organic matter contents through the profiles are given in
Table 18.
It will be noted that during the first year, the fertilizer
application level had little effect on the effluent. This is
2.50 -
2.252.00-
-
1.75
1.501.25
-
1.00-
0.750.50
-
0.250.00
-0.250.50
JAN
1
3
4
5
6
7
8
9
10
427
427
317
317
256
256
235
235
226
226
99.7
16.4
15.6
278
42.1
41.8
14.1
12.1
168
196
11.0
12.3
13.3
22.3
103
201
193
213
214
207
175
264
227
226
205
206
197
196
4
I
MAY
I
JUN
152
121
(
JUL
182
I AUG
ISEPT OCT NOV I DEC
213
244 274
305
335 365
(
HALF
i
I
3
APR
NORMAL
DOUBLE
i
i -f
I
2
I
91
undoubtedly due to the fact that the added fertilizers were
negligible in comparison to the soluble N species present in
the soil. At the 189 lb N /acre /year fertilizer rate it will be
noted that a stimulation of N release occurred and reached
a maximum during the 5th year. It is apparent that the high
rate of fertilizer application increased nitrate in the effluent
over the other two application rates. This higher nitrate
movement would be in line with some observations. It
should be stressed though, that luxury consumption by the
crop was not taken into account. Thus one would expect
-
I
MAR
Figure 20. Predicted daily leachate with time. Positive leachate
indicates drainage, negative leachate indicates upward flux across lower boundary.
55.9
52.3
-.
I
60
TIME (MONTHS AND DAYS)
Half Fertilizer Normal Fertilizer Double Fertilizer
Soil
Application
Application
Application
Segment Initial (67 lb N /acre) (108 lb N /acre) (189 lb N /acre)
2
FEB
I
32
TABLE 18. Organic -N Distribution in Profile (ppm, after
13 years).
5
-
I
6
7
1
1
1
8
9
IO
1
II
1
12
YEAR
Figure 21. Predicted effect on NO,-N concentration in effluent by increasing fertilizer rates.
Page 30
1
13
a somewhat lower value in an actual situation. The 108
lb /acre and 67 lb /acre rates were of considerable interest.
As can be seen in Table 19 the 67 lb /acre rate was not
sufficient to provide the N necessary for crop production
and would represent a nitrogen deficient case. Nevertheless,
it will be noted that the curves cross each other at several
points. This indicates that a fertilizer application timed
so as to provide adequate, but not excessive N does not
contribute to N pollution. It should also be noted that during
the later years at the two higher levels of fertility a cyclic
but different pattern exists. At the highest fertilizer rate
a maximum occurs at the first of the year, and a minimum
in mid -season, whereas, at the 108 lb N /acre a maximum
occurs in mid-summer.
It will be noted at the low rate that starting with year 12
several maximums and minimums occur. Each maximum
follows a fertilizer application. It appears that the higher
rate, 108 lb N /acre, is in some way buffered.
Although one cannot directly compare the results calculated here with analysis of drain effluents, such comparisons
are of interest. In the areas where the 'soil samples were
taken that were used for the calculations, a study of drain
effluents has been conducted (13) . It was found that the N
in drains was cyclic, as predicted, and that the concentrations were within the range calculated here. Thus it is felt
that the work reported here is in agreement with field
observations.
User's Manual For Model
MOISTURE FLOW PROGRAM
INTRODUCTION:
The purpose of this manual is to provide the user with
detailed operating instructions for the Moisture Flow Program. Program input, program output, interfacing with the
Biological -Chemical Program, and re -start capabilities of
the program are discussed in this user's manual. The theory
of Program MOISTRE and its subroutines was discussed
-
TABLE 19. Plant-N Uptake (for half fertilizer application
67 lb N /acre).
Year
1095
1095
1095
1095
1095
1095
1095
1095
1095
1095
1095
1095
1095
1
2
3
4
5
6
7
8
9
10
11
12
13
:
906
935
850
861
849
856
763
783
721
-
K(6)
- 4.67 x
10 -5
e35.80
the appropriate Fortran IV statement function could be
written
CONDUCT(Z)
PROGRAM INPUT:
Input to the Moisture Flow Program is of two types
(A) Input to the source deck of Program MOISTRE, and
(B) data card input to the Moisture Flow Program.
1095
1095
1095
1039
INPUT TO PROGRAM MOISTRE
SOURCE DECK
It is not convenient for the equations relating hydraulic
conductivity (K) to moisture content, and soil moisture
diffusivity (D) to moisture content to be supplied from data
cards because the forms of these equations may vary from
one soil to another. Further, the form of the diffusivity
moisture content relationship may change within a given soil
for the range of moisture contents considered.
Equations expressing soil moisture diffusivity and unsaturated hydraulic conductivity as functions of soil moisture
content are inserted as "statement functions" (16) at the
beginnning of Program MOISTRE. For example, if the
unsaturated hydraulic conductivity (K ) is related to the
moisture constant (B) according to the expression
previously.
PROGRAM LANGUAGE AND COMPUTER TIME
The source program is written in Fortran IV for Control
Data Corporation 6000 series machines (16). Compilation
has been accomplished on the C.D.C. 6400 digital computer
at the University of Arizona using both the RUN and FTN
compiler options. Although the amount of machine storage
required and time needed to compile and execute is highly
dependent on the computer system, on the C.D.C. 6400 the
Moisture Flow Program will compile in a field length of
60,0008 words (including compiler program) under FTN
in about 9 seconds. Compiler output is loaded in approximately 55,0008 words and is executed much more efficiently
when compiled under FTN than under RUN. A 30 node
problem requires approximately three seconds of computer
time to simulate each day under FTN, although this time
will vary as the number of time intervals per day changes.
Actual
(all units Ug /cm2 /yr)
Imposed
= 4.67*
10.**
(-5.) *EXP(35.8*Z)
where Z corresponds to the moisture content. If multiple
relationships are needed to describe these properties over
the desired moisture range, multiple statement functions
must be used.
The diffusivity and conductivity relationships are referenced at three points in Program MOISTRE. Each of these
points is indicated by comment cards in the source deck.
If multiple relationships are used, the appropriate diffusivity
or conductivity statement function must be referenced at
each of the three points.
DATA CARD INPUT TO MOISTURE
FLOW PROGRAM
Data card input to the Moisture Flow Program consists
of the 7 card groups shown in Figure 22. All seven card
groups must be present in a given run, however, the number
of data cards composing some card groups can vary as
indicated in Table 20.
A description of the variables and input format for the
cards in data card groups 1 -7 is shown in Tables 21 -27.
In the following description if the indicated data-name is
Page 31
/Group
#7
Group #6
Tabulated Consumptive Use Values
Root Distributions
Group #5
///
Printed output contains not only the daily moisture
properties and net fluxes, but also a listing of initial conditions, run parameters, and other input and controlling data.
Tables 28 and 29 contain descriptions of the variables in
each type of printed output.
Detailed output from Program MOISTRE is written on
a magnetic tape called TAPE 5 in the program. As presently
compiled the program writes the value of the variables
described in Table 30 on TAPE 5 at 0.1 day intervals,
although with simple program modifications this interval
could be changed.
Blaney -Criddle
Soil
Group #2
Group
Consumptive
Use
Data
Initial Moisture Contents
Group #4
Group #3
#1
Identification
Water Application
Control
Data
Parameters
RESTART CAPABILITY
The Moisture Flow Program was developed so that it
may be executed in successive stages. Utilizing this capacity,
the program can be executed for any period of time from
LL to MM with the following restrictions in LL ( the starting
day number) and MM (the final day number of the run):
(a) 1 < LL < 365,
(b) LL < MM < 365,
(c) LL = first or 16th day of any month.
Figure 22. Data card groups needed in Program MOISTRE.
"real" (16), the decimal point may be punched on the data
card anywhere within the field. If the data -name is "integer,"
no decimal point is permissable and the numeric value must
be right justified within the field. Data -names which are
alpha- numeric may contain either alphabetic or numeric
characters.
PROGRAM OUTPUT:
Output from Program MOISTRE is of two types: (A)
printed output, and (B) output written on magnetic tape
(TAPE 5). An additional magnetic tape (TAPE 4) is used
internally in the program and to restart Program MOISTRE
at days other than day one. A description of the variables
written on TAPE 4 is contained in the Re -Start Capabilities
portion of this Users Manual.
Re -start capability is provided by writing the values of
the necessary re-start variables on magnetic tape (TAPE 4)
on a daily basis. Therefore, if it is desired to re -start the
Moisture Flow Program on day number LL and continue
it through day number MM the following procedure should
be used:
a) Using appropriate control cards for the computer
system skip forward through logical record LL 1 on the
tape assigned as TAPE 4.
b) Execute Moisture Flow Program for days LL to MM.
The Moisture Flow Program will BACKSPACE to read the
values of the necessary re -start variables from day LL 1
to be used as input for day LL. It should be noted that the
values of the variables not designated as restart variables
(See Table 31) will be reassigned from data cards or statement function (for diffusivity and conductivity relationships). The only input variables that will be over -ridden
-
-
TABLE 20. Data card groups of the Moisture Flow Program.
Group
Program Served
No. of Cards
1
Program MOISTRE
1
2
APPSA
5
Program MOISTRE
Program MOISTRE
Program MOISTRE
Subroutine CONUSE
6
Subroutine CONUSE
3
7
Subroutine CONUSE
24
3
4
tö>
General Description
1B
60>Q>
lc
24
Print options, constants, boundary and initial
condition options.
Date and amount of water applications.
Soil identification and horizon depths.
Initial soil moisture content at each node (J).
Input data for Blaney -Criddle method of computing
crop consumptive use tabulated on a semi -monthly
basis beginning Jan. 1.
Fraction of roots occurring in each of top 6 feet of
soil, one card for crop 1, crop 2, and crop 3.
Semi- monthly consumptive use moisture removal
amounts.
AAPPS = the number of individual water applications.
B See Table 23 for explanation of 0.
cThe number of depth nodes (Q) is determined by the distance between the depth nodes (DELX) and the depth to the bottom of the deepest
soil horizon, HOR(0), by the relationship
Q = HOR(0)/DELX -{- 1
where Q is truncated because its data type is integer.
Page 32
TABLE 21. Description of variables on data card comprising Data Card Group
Columns
Data Name
Description
Data Type
Special
Value
1- 5
6 -10
AA
11 -15
CC
16 -20
21 -25
LL
MM
26 -30
BBC
Integer
Integer
Integer
BB
Integer
Integer
Real
Performance
1
1
1
1
< LL < 365
< MM < 365
LL
1
2
(any other)
31 -35
TBC
Real
1
2
(any other)
36 -40
41 -45
YEAR
CROP
Integer
Integer
>
1
1
2
3
Integer
Integer
>0
TM
TD
Real
Real
Real
Real
TD < TM < TS
TD < TM < TS
TD < TM < TS
SM
Real
TD
46 -50
51 -55
M
56 -60
DELX
61 -65
TS
66 -70
71 -75
76 -80
APPS
1.
>0
<
SM
< TS
Print parameters and constants.
Print moisture contents daily.
Utilize initial moisture contents from Group 4 data
cards for internal soil nodes only.
Starting day number (Jan. 1 = day 1).
Last day number of run.
Bottom boundary condition retained at TM.
Bottom boundary condition retained at TS.
Bottom boundary condition retained at this values.
Top boundary condition initialized at TM.
Top boundary condition initialized at TS.
Top boundary condition initialized at this values.
Year number.
Utilize Blaney-Criddle formula to compute
consumptive use for CROP = 1.
Utilize Blaney- Criddle formula to compute
consumptive use for CROP = 2.
Use consumptive use constants on Data Card Group 7.
Minimum number of time intervals per dayA.
Number of water applications, (Number of Data Card
Group 2 cards) .
Distance between depth nodes (cm).
Maximum moisture contents.
Arbitrary moisture contents.
Minimum moisture contents equal to the cut-off
below which no further consumptive use can be
withdrawn by the sink term.
Arbitrary initial moisture contents for internal nodes
if option CC is not used.
ABased on present experience, M should not be less than 100.
BAIL moisture contents are expressed as decimals.
TABLE 22. Description of variables on data cards of Data Card Group 2.
Columns
Data Name
Data Type
Description
21 -22
MON(L)
DATE(L)
AMT(L)
ADENT (L
( )
Integer
Integer
Real
Month of water application.
Day of month of water application.
Amount of water application (cm).
jI = irrigation
Source of application: R
rainfall
24 -25
31 -40
80
Alpha-numeric
P
-
TABLE 23. Description of variables on data cards of Data Card Group 3.
Data Name
Data Type
Description
1- 2
0
3 -10
IDENT
Integer
Alpha-numeric
Real
Number of soil horizonsA, (Number of Data Card Group 3 cards).
Soil horizon identificationA.
Depth from surface to lower boundary of horizon (cm) A.
Columns
11 -20
HOR(N)
Soil "horizons" referred to in this context do not correspond to morphological soil horizons. Program MOISTRE models moisture movement
in uniform soils only, so soil "horizons" as referred to here have no function except to correspond to the "chemistry horizons" in the BiologicalA
Chemical Program for convenience.
Page 33
TABLE 24. Description of variable on data cards of Data Card Group 4.
Columns
Data Name
Data Type
Description
46 -51
TO(J)
Real
Initial soil moisture content of each depth node (J), including
boundary nodes if option CC is used (Table 21).
TABLE 25. Description of variables on each of the 24 data cards of Data Card Group 5.
Columns
1
-10
11-20
21 -30
31 -40
Data Name
Data Type
Description
MEANT1(I)A
Real
Pl (I)8
KA1(I)c
KB1(I) D
Real
Mean air temperature in °F for each semi -monthly period.
Percent of annual daylight hours occurring in each semi-monthly period.
Real
Blaney- Criddle semi-monthly crop consumptive use coefficient for crop
Real
Blaney -Criddle semi-monthly crop consumptive use coefficient for crop = 2.
A For
second semi -monthly
For second semi -monthly
c For second semi -monthly
D For second semi -monthly
E
period
period
period
period
= 1.
in each month this variable is named MEANT2 (I).
in each month this variable is named P2(I).
in each month this variable is named KA2(I).
in each month this variable is named KB2(I).
TABLE 26. Description of variables on each of the three data cards of Data Card Group 6.
Data Name
Data Type
Description
-10
KP(1)A
Real
Decimal fraction of roots located in top foot of soil profile.
11 -20
KP(2)A
Real
Decimal fraction of roots located in 2nd foot of soil profile.
21 -30
KP(3)A
Real
Decimal fraction of roots located in 3rd foot of soil profile.
31 -40
KP(4)A
Real
Decimal fraction of roots located in 4th foot of soil profile.
41 -50
KP(5)A
Real
51 -60
KP(6)A
Real
Decimal fraction of roots located in 5th foot of soil profile.
Decimal fraction of roots located in 6th foot of soil profile.
Columns
1
AData name is KP(I) for crop
=
1,
KPI(I) for crop =
2, and
KP3(I) for crop
-
3.
TABLE 27. Description of variables on data cards in Data Card Group 7.
Columns
Data Name
Data Type
Description
21-30
U
Real
Semi -monthly consumptive use moisture removal constants (inches /1/2 month)A.
A I st
-
15th is first half of each month, 16 - end of month is second half.
Page 34
TABLE 28. Description of variables printed as initial conditions, run parameters, and constants if print option AA
Data Name
=
1.
Description
AA
BB
CC
LL
MM
BBC
TBC
YEAR
CROP
See description of variables in Data Card Group
1
(Table 21)
M
APPS
DELX
TS
TM
TD
SM
=
L =
TME (L)
L
MON(L)
DATE (L)
-
1,
APPS
APPS
APPS
1, APPS
1, APPS
1,
AMT(L)
ADENT (L)
L
L
L
IDENT
N=1,0
=
=
Day number of water application.
1,
See description of variables in Data Card Group 2 (Table
22).
23).
HOR(N)
N-1,0
See description of variables in Data Card Group 3 (Table
TH(J)
MEANTI(I
J
Initial soil moisture content of each depth node (J).
KB1(I)D
= I, Q
1=1,12
I=1,12
= 1, 12
1=1,12
UH(I)
I
KP(1)E
1=
A
PI (I)B
KA1(I)c
See description of variables in Data Card Group 5 (Table 25) .
1
=
1,
Semi -monthly consumptive use moisture removal constants
(cm /1/2 month) to be used if CROP = 3.
24
See description of variables in Data Card Group 6 (Table
1, 6
AFor
B For
c For
DFor
second semi -monthly period in each month, the variable is named
second semi-monthly period in each month, the variable is named
second semi -monthly period in each month, the variable is named
second semi- monthly period in each month, the variable is named
EData-name is KP(I) for CROP = 1, KP1(I) for CROP = 2, KP3(I)
MEANT2(I).
by restarting are the initial soil moisture contents and initial
values for the upper and lower boundary conditions. The
complete data deck must be used.
If it is desired to execute the Moisture Flow Program
beyond 365 days, the following procedure is recommended:
(a) Generate through 365 days for previous year.
Lions are over-ridden by the
P2(I).
KA2(I).
KB2(I).
for CROP
rent year.
.
through MM = 365.
It should be emphasized that the mass balance computations are based on initial conditions at the start of the
original simulation, even though the values of these condi-
3.
"re -start variables." 1f the
original inputs are not changed, the mass balance check will
be valid following re- starts even at times greater than one
year.
PROGRAM INTFACE
(b) Change data cards for inputs appropriate for cur(c) Skip back on re -start tape (TAPE 4) correct number of logical records (365)
(d) Generate current year by running from LL = 1
26).
Program INTFACE is an interfacing program to convert the output from the Moisture Flow Program (TAPE 5)
to the appropriate form for input to the Biological -Chemical
Program (TAPE 1). Because of differences the length of
¿X in the two programs, it is not feasible to generalize the
program, so the user must write an interfacing program
similar to Program INTFACE as listed as an example in
Appendix A.
Page 35
TABLE 29. Description of variables printed daily.
Data Name
Description
II
Day number.
Decimal fraction of day II completed.
Number of month corresponding to IÌ.
Day of month corresponding to II.
Cumulative leachate at end of day II (cm).
Mass balance check on CL (cm).
Cumulative infiltration at end of day II (cm).
Cumulative consumptive use (evapotranspiration) removed at
end of day II (cm).
Soil moisture storage difference at end of day II relative to initial
moisture content of profile (cm).
Number of time intervals required in day II.
Soil moisture content at end of day IIA.
Day number of water applicationB.
Amount of water (cm) to infiltrate at start of day = TME(L)B.
XT
MONTH
IDTE
CL
CHECK
ETS
ET
DIF
I
TN(J)
TME(L)
= 1,Q
L = 1, APPS
J
HED
only if BB = 1 (Table 21).
Printed only at start of day = TME(L).
A Printed
B
TABLE 30. Description of variables written on magnetic tape (TAPE 5) at the end of each output periodA.
Data Name
Description
CI
Day Number.
Decimal fraction of day II completed.
Number (subscript) of depth node.
Moisture content of each depth node (J) (cm3 /cm3).
Amount of deficit soil moisture (cm) for the output periodA.
Net soil moisture flux between depth nodes (J) and (J + 1) for
the output period (cm) A, where positive values indicate net
downward fluxes.
Cumulative infiltration (cm), from (downward surface flux).
CL
HED
ETS
Cumulative leachate (cm).
Amount of water remaining to infiltrate (cm).
Cumulative infiltration (cm), from (all surface flux).
II
XT
J
TN(J)
Z(J)
SF (J)
U(J)
= 1,Q
J=1,Q
J=1,Q
J
J=1,Q
Semi -monthly consumptive use moisture rate for each depth
node (J) (cm /day)B.
AOutput period is presently 0.1 day, which corresponds to the input requirements of the Biological-Chemical Program.
B 1st - 15th is first half of each month, 16 - end of month is the second half.
Description of the variables written on TAPE 5 and
TAPE 1 are continued in the Users Manual for the Moisture
Flow Program and Biological-Chemical Program, respectively. The following discussion points out some of the
principles essential to this TAPE 5 - TAPE 1 conversion in
the order the variables are written on TAPE 1.
(a) II, M, M are non-essential dummy variables reserved for future use.
(b) SEGVOL(J) is volume of water in each soil segment of Biological-Chemical Program. It is cornputed from a weighted average of the moisture
content of all nodes (from Moisture Flow Program) in that segment.
Page 36
(c) MOISIN(J)
is volume of moisture moving across
the upper boundary of each soil segment (in Biological- Chemical Program). It is computed by
averaging the values for soil moisture flux (from
Moisture Flow Program) at the two nodes nearest
to the segment boundary.
(d) MOISOUT(J). Analogous to (c) except MOISOUT(J-1) = MOISIN(J).
(e) TEN(J). Average soil moisture tension (cm of
H2O) of each soil segment. Correct numerical
values should be computed from the moisture content tension relationship only at times when the
TABLE 31.
Description of variables designated as re -start variables. These variables are re- initialized from TAPE 4 when
the Moisture Flow Program is re- started.
Data Name
Description
TN(J)
FN(J)
Soil moisture content of each depth node (J).
Soil moisture flux between depth nodes (J) and (J
CI
+ 1) which occurred during the previous time
interval where positive values indicate net downward fluxes.
Cumulative leachate (cm).
Mass balance check (cm) on cumulative leachate.
Largest flux rate [FN(J) /DELI] during last time interval of previous run.
Subscript determining next moisture application.
Quantity of water (cm) remaining at soil surface to infiltrate.
Soil moisture contents at each depth node (J) that are anticipated to exist at the end of the first
time interval of the restart run.
Cumulative infiltration (cm), from (downward surface flux).
ETS
Cumulative flux at the soil surface (cm), from
ET
Cumulative consumptive use (evapotranspiration) of soil moisture (cm).
CL
CHECK
IR
L
HED
ANT (J)
tension is greater than 10 bars. Otherwise any value
in the range of 0 < TEN(J) < 10,300 cm. yields
identical results.
(f) U(J) as written in Tape 5 is volume of water
consumed /unit volume of soil /day. It must be converted to volume of water consumed /soil segment/
time interval for the Biological -Chemical Program.
This conversion is necessary only if the variable
CROP (in Biological -Chemical Program) is equal
to 1.
BIOLOGICAL-CHEMICAL PROGRAM
INTRODUCTION:
The purpose of this manual is to provide the user with
detailed operating instructions for the Biological-Chemical
Program. The manual is written with the assumption that
the user has read the sections of this report pertaining to the
program's concepts and theoretical basis. References are
made to earlier passages and diagrams to clarify certain
technical points. The manual includes general and specific
discussions of the types of data (e.g. soil data, moisture flow
data, etc.) needed to run the program as well as the types of
output data which may be obtained. Use or generation of all
input and output media such as printed output, data card,
and magnetic tapes and discs, is discussed in detail. The
input and output for a sample run are included in the
Appendix to illustrate use of the program.
(all surface flux).
PROGRAM LANGUAGE AND COMPILATION:
The source program is written in FORTRAN IV computer language for Control Data Corporation 6000 series
machines (16) . Compilation has been successfully accomplished using the RUN and FTN fortran compiler versions
for the C.D.C. 6400 located at the University of Arizona,
Tucson, Arizona, and the FTN fortran compiler version for
the C.D.C. 3800 located at N.O.A.A., Boulder, Colorado.
The amount of machine space and time needed to compile
and execute the program is highly machine dependent.
However, the program was compiled on the C.D.C. 6400
under FTN fortran using a field length of approximately
70 K octal words (60 binary bits each). The compiler
output was loaded and executed with a field length of
approximately 66 K octal words. Compilation time was
about 40 seconds.
PROGRAM INPUTS:
Input media to the Biological- Chemical program consist
of data cards and /or magnetic tape. Basic control data,
soils data, fertilizer and organic matter application data, and
any plant uptake data are read in from cards. Moisture flow
data including irrigation and rain inputs, flow between soil
segments, soil moisture content and consumptive use data
are read from magnetic tape. An option also allows this data
to be read from cards. The following section (Section No. 1)
gives a detailed discussion of the punch card inputs. Magnetic tape inputs are discussed beginning on page 46.
Page 37
Section No.
1
Group X16 Plant Uptake of Nitrogen
15
Root Distribution
Grou P
Or.anic A.plications
Grou. #14
Fertilizer Application
Group #13
CARD INPUTS
Irrigation Water Application Dates
Organic Application Dates
Group #11
Fertilizer Application Dates
Group #10
Group #12
The card input consists of 16 basic card groups of one
or more cards each (Figure 23) . All groups except numbers
7, 8, 9, 15, and 16 must be present whenever a run is made.
Inclusion of Group 7 cards allows the program to be run
with a set of constant flow data for each time step. For
example, a run can be made involving constant soil moisture
content and /or moisture movement with respect to each
soil segment (see page 5 for details concerning segments
and horizons) When this group is present, TAPE 1 (input
from the Moisture Flow Program) is not read. Group 7 must
be absent if TAPE 1 is being read.
Card Group 8 must be present whenever a restart data
deck or restart data written on TAPE 3 are not available.
When Group 8 is present, the program must be started from
the initial starting time. Group 9 must be absent if Group 8
is present.
Card Group 9 allows the program to be restarted using
the card deck generated in a previous run. Inclusion of
Group 9 dictates that Group 8 can be omitted.
Groups 15 and 16 must be included if plant root distributions and plant uptake of nitrogen data are to be read
from cards. A detailed description of each card group
follows Figure 23.
Group
Restart Data
#4
Group
Group
Group
Initial
#8
7
#6
Soil Analysis
Flow Data
Irrigation
ater Analysis
I
Tempera ure Jata
#5
Group
Component Horizon Depths
4
Group
Temperature Horizon Depths
#3
Group
Control Cards
#2
Group
Group
.
#1
Title Card
Optional
Figure 23. Card groups needed in Biological-Chemical Program data deck.
Page 38
CARD GROUP NO.
Title
Card 1 of 1
Columns
1
Data Name on
Printed Output
-80
1
Card
Data Type
Description
ALPHA
Any title desired on printed output.
CARD GROUP NO. 2
Control Cards
Card 1 of
Columns
1-
5
6 -10
3
Data Name on
Printed Output
Data Type
Description
SOIL SEGMENT
SIZE
REAL
Soil segment size (cm). See page 41 for details.
TIME INTERVAL
REAL
Time interval size (days) corresponding to intervals for moisture
flow on Tape 1.
REAL
Ratio of water to soil in the soil extract (gm water /gm soil).
1
REAL
Convergence criterion for nitrogen transformation subroutine.
See page 41 for details. Suggested values are in the range
0.1 - 10.0 ppm nitrogen.
CONVERG 2
REAL
See page 41
Convergence criterion for ion exchange subroutine. "2
-5
1 X 10
for details. Suggested values are in the range 1 x 10
SIZE
11 -15
1.6
-20
21 -25
XTRACT
CONVERG
-
moles /liter.
REAL
Shut -off criterion for nitrogen transformation subroutine. See
page 41 for details. Suggested values are in the range 0.1 - 2.0
ug /soil segment/time step.
CHECK
REAL
Shut -off criterion for ion exchange subroutine. See page 41 for
details. Suggested values are in the range 1.0 - 5.0 ug /soil
segment /time step.
36-40
REDUCE
REAL
Number of time intervals to be used within each TIME
INTERVAL SIZE mentioned above should any nitrogen mass
deficits occur. See page 41 for details. Suggested values are in
the range 5 -10.
41 -45
UPTAKE(NO3)
REAL
Fraction of total plant uptake of nitrogen as NO3 -N. A
suggested value is 0.95. As NO; -N mass --* 0.0 plant uptake
of NO-3-N -* 0.0 regardless of plant uptake imposed
26 -30
CHECK
31 -35
1
on system.
46 -50
UPTAKE(NH4)
REAL
Fraction of total plant uptake of nitrogen as NH4 -N. A suggested
value is 0.05. Fraction as NO3 -N plus fraction as NH4 -N must
equal unity. The same relationship for NO3 -N holds for NH4 -N
uptake with respect to the zero mass boundary condition.
51 -55
None
REAL
Plant -N uptake constant for use with consumptive use values
(if used)
.
Page 39
Card 2 of 3
Columns
Data Name on
Printed Output
Data Type
Description
Starting day of run relative to time reference date.
(e.g. if reference date is January 15 and starting day
for run is January 21, the relative starting day would
be day 7).
Termination day of run relative to time
reference date.
Number of soil chemistry horizons (must be in range
1 to 9 inclusive) .
If 1, consumptive use used to determine N- uptake
by plants.
If 2, reserved for future use.
If 3, read plant N- uptake data from cards (see card
groups 15 and 16) .
Number of temperature horizons (must be in range
1 to 4 inclusive)
Number of weekly temperature data cards
(see group 5)
Print interval (days) for predicted soil chemistry data.
Time interval within a day on which the IPRINT
and IMASS print options are to be activated.
Write interval (days) for output to TAPE 2 (see
SECTION 3) .
If 0, program is to be run from initial input deck.
If 1, program is to be restricted from tape of
restart deck.
If 0, no restart data deck will be punched.
If 1, a restart data deck will be punched. (A restart
tape (No. 3) is always written)
If 0, program is to be restarted from TAPE 3, or
started from initial data.
If 1, program is to be restarted from cards (See
Group 9)
If 0, moisture flow data is read from TAPE 1.
If 1, moisture flow data is read from cards (See
Group 7) .
Reference date in reference month (e.g. March 21
would be STARTING DAY = 21) See below.
Reference month. Month to which all starts of the
program are referenced (e.g. if reference month is
March, STARTING MONTH = 3)
Year for this run (e.g. if this is the third year being
run, YEAR = 3)
1- 5
RELATIVE STARTING
DAY
INTEGER
6 -10
INTEGER
11 -15
RELATIVE TERMIN
DAY
NO. OF CHEMISTRY
16 -20
HRZNS
CROP
INTEGER
INTEGER
NO OF TEMP
HRZNS
NT
21 -25
26 -30
INTEGER
.
INTEGER
.
36 -40
IPRINT
JPRINT
INTEGER
INTEGER
41 -45
INK
INTEGER
46 -50
IRERUN
INTEGER
51 -55
IPUNCH
INTEGER
31 -35
.
INTEGER
IREADP
56 -60
.
61 -65
ITEST
INTEGER
66 -70
STARTING DAY
INTEGER
71 -75
STARTING MONTH
INTEGER
.
YEAR
76 -80
INTEGER
.
Card 3 of
Columns
Data Name on
Printed Output
Data Type
Description
1- 5
ISTOP
INTEGER
6 -10
IMASS
Year when run terminates (e.g. if run is to terminate after
3 years and starts with year 3, ISTOP = 5) .
Print interval (days) for summary of nitrogen balance for system.
If 1, basic control card data are printed. If 0, printing of above
is suppressed.
If 1, input data are printed.
If 0, printing of above is suppressed.
3
11 -15
IPRINT I
INTEGER
INTEGER
16 -20
IPRINT J
INTEGER
Page 40
ADDITIONAL DETAILS FOR CARD GROUP 2
SOIL SEGMENT SIZE. Soil segment size (or DELX, see
Figure 1) must be in the range [depth (cm) to water table/
(25
1)] < SOIL SEGMENT SIZE < the size (cm) of
the largest chemistry or temperature horizon. Here the 25
refers to array size currently used in the program.
CONVERGE 1. This constant determines the accuracy of
the nitrogen changes computed in Subroutine TRNSFM.
A smaller value will increase accuracy and program execu-
-
tion time.
CONVERGE
2. This constant determines the accuracy
of mass changes in the system computed in subroutine
XCHANGE. A smaller value will increase accuracy and
program execution time.
CHECK 1. This constant is used in subroutine CHK to
determine if Subroutine TRNSFM should be called for that
time step or by- passed and the previously computed nitrogen changes used. If the rates of change for nitrogen are
less than CHECK 1, TRNSFM is by-passed. However,
TRNSFM is called at least once each day to avoid possible
"drift" in the calculations.
CHECK
2. This constant is used in Subroutine CHK to
determine if Subroutine XCHANGE should be called for
that time step or by- passed, in which case previously computed changes due to ion exchange, etc. are set equal to
zero. XCHANGE is called at least once each day.
REDUCE. This constant allows the program to use smaller
time increments than those specified by TIME INTERVAL
SIZE for cases where the system becomes deficient in nitrogen mass. A larger value of REDUCE tends to minimize
mass balance errors which occur as the system becomes
mass deficient.
CARD GROUP NO.
3
Temperature Horizon Depths
Card 1 of
Columns
1
Data Name on
Printed Output
Data Type
Description
1- 5
TEMPERATURE HRZN
DEPTHS
REAL
Depth (cm) from surface to bottom of 1st temperature
horizon.
6 -10*
Same as above
REAL
Depth (cm) from surface to bottom of 2nd temperature
horizon (if it exists)
.
*The program allows the inclusion of up to 4 temperature horizons. If included, the depths, for numbers
11 -15 and 16 -20, respectively.
3
and 4 would be punched in columns
CARD GROUP NO. 4
Chemistry Horizon Depths
Card 1 of
Columns
1
Data Name on
Printed Output
Data Type
Description
1- 5
CHEMISTRY HORIZON
DEPTHS
REAL
Depth (cm) from surface to bottom of first chemistry
horizon.
6 -10*
Same as above
REAL
Depth (cm) from surface to bottom of second
chemistry horizon.**
*The program allows inclusion of up to 9 chemistry horizons. If included, the depths for numbers 3, 4, 5, 6, 7, 8, and
columns 11 -15, 16 -20, 21 -25, 26 -30, 31 -35, 36-40, 41 -45, respectively.
* *If only one chemistry horizon is desired, only one need be included.
Page 41
9
would be punched in
CARD GROUP NO.
5
Temperature Data
Card 1 of NT*
Columns
Data Name on
Printed Output
1- 2
3 -10
10-20**
Description
Data Type
TEMPERATURE
(DEG C)
REAL
Same as above
REAL
Card identification (not read by program).
Weekly temperature ( °C) for upper most (first) temperature
horizon.
Weekly temperature ( °C) for second temperature
horizon.***
*NT is the number of temperature data cards. Each card contains weekly data for all temperature horizons.
* *The program allows inclusion of up to 4 temperature horizons. If included, temperature data for horizons
columns 21 -30 and 31 -40, respectively.
* * *If only one temperature horizon is desired, only one need be included.
3
and 4 would be punched in
Note: The first temperature data card should correspond to the week beginning with the reference date (see SECTION No.
5
for exceptions).
CARD GROUP NO. 6
Irrigation Water Analysis
Card 1 of
Columns
1
1- 5
6 -10
11-15
16 -20
21 -25
26 -30
31 -35
36-40
41 -45
Data Name on
Printed Output
Data Type
Description
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
NI-1+4
(all units in meq /L of the species shown).
IRRIGATION WATER
ANALYSIS
Same as above
Same as above
Same as above
Same as above
Same as above
Same as above
Same as above
Same as above
NO
3
Ca"
Na+
Mg ++
HCO -3
CíCO -3
S0 -4
Note: All irrigation water is assumed to have same analysis.
CARD GROUP NO. 7
Moisture Flow Data
Card 1 of NS*
Columns
Data Name on
Printed Output
Data Type
Description
-10
I1 -20
SEGVOL
None
REAL
REAL
21 -30
None
REAL
31 -40
None
REAL
41 -50
None
REAL
Volume of water in segment (cc).
Water movement across upper boundary of segment (cc /time
step ) * *.
Water movement across lower boundary of segment (cc /time
step) * *.
Average moisture tension (cm) over time step. (tensions shown
as negative) .
Plant water uptake (cm /time step /soil segment).
1
*NS is the number of moisture flow data cards. There must be a card for each segment including No.
see page 125.
* *Positive sign for downward flow, negative for upward flow.
Page 42
1.
For details in computing NS,
CARD GROUP NO. 8
Initial Soil Analysis
Card 1 of NC*
Columns
Data Name on
Printed Output
Data Type
Description
(Units in meq /L of species shown unless otherwise noted)
NH +4 (soluble form)
NO-3
UREA
1- 5
INITIAL SOIL
ANALYSIS
REAL
6-10
Same as above
Same as above
Same as above
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
11 -15
16 -20
21 -25
Same as above
26-30
31 -35
36-40
41-45
46 -50
51 -55
56 -60
61 -65
Same
Same
Same
Same
Same
None
None
None
66 -70
71 -75
None
None
REAL
REAL
76 -80
None
REAL
as above
as above
as above
as above
as above
Ca"
Na+
Mg ++
HCOCICO -3
S0 =4
Exchange Capacity (meq /100 gm soil).
Gypsum (meq /100 gm) soil.
If 0.0, no lime is present in soil.
If 1.0, lime is present in soil.
Bulk Density (gm /cc of soil).
Soil organic matter (ug /gm soil). This refers to entire mass
of organic matter not to the organic nitrogen. The assumption
is made in the program that the organic matter is 40% carbon
on a dry weight basis.
Carbon-Nitrogen ratio of organic matter (e.g. 40:1 would
be punched as a 40.0) .
*NC is the number of chemistry horizons.
CARD GROUP NO. 9
Restart Data
This data group is punched by the program during a previous run. See page 125 for details. The punch /read format
is ( 415/,( 6E13. 5/6E13.5/6E13.5/6E13.5/E13.5)).
CARD GROUP NO. 10
Fertilizer Application Dates
Card 1 of 1**
Columns
1- 5
Data Name on
Printed Output
FERTILIZER
APPLICATION
DATES
6 -10
Same as above
11 -15*
Same as above
Data Type
Description
INTEGER
INTEGER
INTEGER
Number of fertilizer applications.
First application day relative to reference starting date.
Second application day relative to reference starting date.
*The program allows inclusion of up to 25 fertilizer application dates. The same format, I5, is used for any additional dates desired.
* *A second card may be used if needed (i.e. if the number of applications exceeds 15, in which case the I5 format still applies.
Page 43
CARD GROUP NO.
11
Organic Matter Application Dates
Card 1 of 1
Columns
Data Name on
Printed Output
1- 5
6 -10
11 -15*
ORGANIC MATTER
APPLICATION
DATES
Same as above
Data Type
Description
INTEGER
INTEGER
Number of organic matter applications.
First organic matter application day relative to
reference date.
INTEGER
Second organic matter application day relative to
reference date.
*The program allows inclusion of up to 5 organic matter application dates. If included, application dates for applications 3, 4, and
punched in columns 16 -20, 21 -25, and 26 -30, respectively.
5
would be
CARD GROUP NO. 12
Irrigation Water Application Dates
Card 1 of 1 **
Columns
Data Name on
Printed Output
Data Type
Description
1- 5
None
INTEGER
Number of irrigations.
6 -10
IRRIGATION WATER
APPLICATION
DATES
INTEGER
First irrigation day relative to reference date.
INTEGER
Second irrigation day relative to reference date.
11 -15*
Same as above
*The program allows inclusion of up to 25 irrigation dates. If included, applications 3 -25 would follow the same 15 format.
* *A second data card may be needed if more than 15 irrigation dates are used.
CARD GROUP NO. 13
Fertilizer Applications
Card 1 of NF*
Columns
Data Name on
Printed Output
REAL
1- 5
6 -10
Data Type
FERTILIZER
APPLICATIONS
11 -15
Same as above
REAL
REAL
16 -20
Same as above
Same as above
Same as above
Same as above
REAL
REAL
REAL
REAL
21 -25
26 -30
31 -35
Description
All units in lbs /acre of species shown unless otherwise
labeled.
Depth (cm) of a uniform fertilizer application. If 0.0,
a surface application is indicated.
NI-I+4
Urea (NH2-C-NH2)
NO3
a
Ca"
SO -4
CO
3
*NF is the number of fertilizer applications. The maximum number allowed in the program is 25.
Page 44
CARD GROUP NO. 14
Organic Matter Applications
Card 1 of NO*
Columns
Data Name on
Printed Output
1- 5
6 -10
Data Type
Description
REAL
Depth (cm) of uniform organic matter application.
(Surface applications are not allowed.)
Carbon:Nitrogen ratio of organic matter (e.g. 40:1
would be punched as a 40.0)
Organic matter added (lbs /acre) as oven dry weight.
C:N RATIO
REAL
ORGANIC MATTER
APPLICATIONS
REAL
.
11-15
*NO is the number of organic matter applications. The maximum number allowed in the program is 5.
CARD GROUP NO. 15
Plant Root Distribution
Card 1 of
Columns
I
Data Name on
Printed Output
Data Type
Description
PLANT ROOT
DISTRIBUTION
REAL
Fraction (decimal) of plant roots from 0 -1 ft. depth.
11 -20
Same as above
21 -30
Same as above
31 -40
Same as above
41 -50
Same as above
51 -60
Same as above
REAL
REAL
REAL
REAL
REAL
Fraction from 1' - 2'.
Fraction from 2' - 3'.
Fraction from 3' - 4'.
Fraction from 4' - 5'.
Fraction > 5'.
1
-10
Note: Plant root distribution is independent of time. If roots do not extend to 5', use zero fractions for roots below their deepest extension.
CARD GROUP NO. 16
Plant Uptake of Nitrogen
Card 1 of NP*
Columns
-10
11 -20
Data Name on
Printed Output
Data Type
Description
Space for card identification.
1
*
PLANT UPTAKE OF
NITROGEN
Plant uptake of nitrogen (lbs -N /acre/semi- monthly).
REAL
*NP is the number of semi -monthly ** plant uptake data cards. The program requires that 24 cards be present, even if not all of them are used.
*Semi- monthly means the period from the 1st day thru the 15th day or from the 16th day thru the last day of the month. The 1st data card
begins with the semi -monthly period containing the reference starting date (See page 113) Remaining data cards contain data for consecutive
semi -monthly periods taken chronologically from the 1st.
.
Page 45
Section No.
2
TAPE INPUTS
Tape input to the Biological -Chemical program consists
of two optional tapes written in binary. TAPE i contains
moisture flow data written by program 1NTFACE. An
alternate procedure is to input moisture data on cards. In
this case a single set of constant moisture data is read.
TAPE 3 may be read to restart the program after a previous
run. This tape is always written at the conclusion of a run.
Unless a magnetic tape is equipped to tape unit 3, the binary
data is written on a disc or drum. Disc or drum data may be
lost at the conclusion of a run. The alternative to a restart
from TAPE 3 is a restart from data cards.
Page 46
Logical Record
l of NR
Field No.
TAPE NO.
Data Name on
Printed Output
Data Type
Description
Reserved for future use.
Reserved for future use.
Reserved for future use.
Current volume of water (cc) in Jth* soil segment.
Moisture flow (cc /time step) into the Jth soil segment.
Moisture flow (cc /time step) from the Jth soil segment.
Average current moisture tension (cm H2O) for Jth segment
(sign ±).
Consumptive use (cc /time step) for the Jth segment.
4
CMH2O
5
6
7
None
None
None
INTEGER
INTEGER
INTEGER
REAL
REAL
REAL
REAL
8
None
REAL
1
2
3
1
-
*This sequence of 8 fields is repeated Q ** times per logical record.
* *Q is the total No. of segments. Its value may be computed using the algorithm outlined on page
NR is the number time steps for which data is written on TAPE 1.
Logical Record
1 of 1
Field No.
TAPE NO.
3
Data Name on
Printed Output
Data Type
Description
16
17
None
None
None
None
None
None
None
None
None
None
None
None
None
None
None
None
None
INTEGER
INTEGER
INTEGER
INTEGER
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
18
19
None
None
20
None
21
None
None
None
None
None
None
None
None
None
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
Restart counter for plant uptake data.
Restart counter for fertilizer application data.
Restart counter for organic matter applications data.
Restart counter for temperature data.
Ug of NH4 -N contained in Jth** segment.
Ug of NOS-N contained in Jth segment.
Ug of Urea -N contained in Jth segment.
Ug of Ca ++ contained in Jth segment.
Ug of Na+ contained in Jth segment.
Ug of Mg ++ contained in Jth segment.
Ug of HCO-3 contained in Jth segment.
Ug of Cl- contained in Jth segment.
Ug of C0 =3 contained in Jth segment.
Ug of S0 =4 contained in Jth segment.
Exchange capacity of Jth segment.
Gypsum concentration in Jth segment (moles /L).
If 1.0, lime is present in Jth segment.
If 0.0, lime is not present in Jth segment.
Soil bulk density of Jth segment.
Ug of organic matter just applied to Jth segment.
C:N ratio of organic matter in Jth segment.
Ug of organic -N in Jth segment.
Residue nitrogen in Jth segment (Ug /g).
Residue carbon in Jth segment (Ug /g).
Exchangeable Ca ++ in Jth segment (moles /g).
Exchangeable Mg ++ in Jth segment (moles /g).
Exchangeable Na' in Jth segment (moles /g).
Undissociated CaSO4 in Jth segment (moles /L).
Undissociated MgSO4 in Jth segment (moles /L).
Exchangeable NH +4 in Jth segment (moles /g).
1
2
3
4
5*
6
7
8
9
10
11
12
13
14
15
22
23
24
25
26
27
28
29
*Fields No. 5 -29 inclusive are repeated Q times in each logical record. Q is the number of segments and may be determined using the
algorithm on this page.
**The segments begin with J = 1 and end with J = Q.
The algorithm for computing Q may be written as follows.
Q = DEPTH to W.T. /DELX + 1.1,
where any fraction is dropped in determining the final value for Q.
Page 47
Section No. 3
CARD OUTPUTS
Card output from the program consists of data needed
to restart a run after a previous execution. This card deck
is generated only if the proper control card request has been
made (see Card Group No. 2) . No card deck is punched
if a program run terminates abnormally (e.g. a fatal error
occurs) . A discussion of the punch format is presented in
Section No. 1, under Card Group No. 9. See TAPE 3,
page 123 for variable descriptions.
Page 48
Section No. 4
TAPE OUTPUTS
Tape output from the Biological-Chemical program con-
sists of one BCD (TAPE 2) and one binary (TAPE 3) file.
TAPE 2 is formated in such a manner that the file can be
copied to the print file with single spacing. TAPE 3 contains
restart data which may be read into the program to restart
a previously terminated run.
TAPE NO.2
Logical Record
1 of NR
Data Name on
Printed Output
Data Type
None
None
None
None
None
None
None
None
None
None
None
None
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
None
None
None
None
None
None
None
None
None
None
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
REAL
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Description
Space (blank) .
Water leached since start of run (cc).
Water leached since previous record was written (cc /cm2).
NO3 -N leached since start of run (ug /cm2).
NO3 -N leached since previous record was written (ug /cm2).
NH4 -N leached since start of run (ug /cm2).
NH4 -N leached since previous record was written (ug /cm2).
Urea-N leached since start of run (ug /cm2).
Urea-N leached since previous record was written (ug /cm2).
Ca ++ leached since start of run (ug /cm2).
Ca ++ leached since previous record was written (ug/cm2).
Na+ leached since start of run (ug /cm2).
Na+ leached since previous record was written (ug/cm2).
Space (blank).
Mg ++ leached since start of run (ug /cm2).
Mg ++ leached since previous record was written (ug /cm2).
HCO -3 leached since start of run (ug /cm2).
HCO -3 leached since previous record was written (ug /cm2).
Cl- leached since start of run (ug /cm2).
Cl- Ieached since previous record was written (ug /cm2).
CO -3 leached since start of run (ug /cm2).
CO -3 leached since previous record was written (ug /cm2).
SO -4 leached since start of run (ug /cm2).
SO -4 leached since previous record was written (ug /cm2).
NR is the number of records written on TAPE 2. The write interval (i.e. time between write operations is specified by the user (see Card
Group No. 2).
Note: The format used in writing each logical record is (IX, 12E10.3). The data on TAPE 2 may serve as input to routines which consider
saturated flow and saturated chemistry.
Page 49
Section No.
1.
2.
3.
4.
5.
6.
5
HINTS ON PROGRAM USE
Be sure core is set to zero before program is loaded.
The program does not initially rewind TAPE 1 and
TAPE 2. The user is responsible for the initial positions
of these tapes.
An end -of -file is written on TAPE 2 at the conclusion of
a run. This means that output from several runs may be
stored as separate files on the same or individual tapes.
A run which exits due to a time limit or other error will
not produce a restart deck or tape.
The number of temperature cards may be reduced when
making a restart run by altering the value of the number
contained in Field No. 4 of the restart deck or tape.
The number placed there by the program is the number
of cards or records to skip in order to locate the correct
temperature data card.
If no plant uptake of N is required, set CROP equal to 1
and leave columns 51 -55 of the first control card blank.
In this case, CARD GROUP 16 may be omitted from
the deck.
Page 50
APPENDIX A
PROGRAM LISTINGS
Page 51
LISTINGS FOR MOISTURE FLOW PROGRAM
MOISTR£
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
CONDUCTIVITY ANO DIFFUSIVITY FUNCTIONS.
MOISTRE
NOTE- -CARDS IN THIS SECTION MUST BE CHANGED FOR DIFFERENT SOILS.
MOISTRE
*EXP(35.8
*
*
10. * *( -5.)
Z)
CONDUCT(Z) =4.6T
MOISTRE
/
(Z *Z)
*
EXP(35.8*Z - 0.236/Z)
OIFUSEI(Z) =6.15 * 10. * *( -4.)
MOISTRE
*EXP(25.3
*
Z)
DIFUSE2(Z) =6.33
*
10. * *( -1.)
*EXP( -0.9
MOISTRE
*
Z)
OIFUSE3(Z) =2.72
10. * *( +4.)
*
MOISTRE
READ PRINT OPTIONS, RUN PARAMETERS, WATER APPLICATIONS, PROFILE DA MOISTRE
READ 100 ,AA,BB,CC,LL,MM,80C,TBC,YEAR, CROP,M,APPS,DELX,TS,TM,TD,SM MOISTRE
MOISTRE
READ 106,(MON(L), DATE (L),AMT(L),ADENT(L),L= 1,APPS)
MOISTRE
READ 101,(O,IDENT,HOR(N),N =1,0)
MOISTRE
MOISTRE
COMPUTATION OF TIME OF WATER APPLICATIONS.
MOISTRE
DO 600 L =1,APPS
MOISTRE
AMT(L)= AMT(L)*'2.54
MOISTRE
START =0
MOISTRE
DO 29 L= 1,APPS
MOISTRE
THE (L)= DAY(DATE(L),START,MON(L))
MOISTRE
MOISTRE
ESTABLISH MOISTURE DISTRIBUTION AND INITIALIZE CERTAIN VARIABLES.
MOISTRE
DELTM =1. /M
MOISTRE
KSATD= CONOUCT(TS)
MOISTRE
DELT = DELTM
MOISTRE
Q= HOR(0) /DELX +1.1
MOISTRE
L =1
MOISTRE
G =DELX
MOISTRE
IF(90C.EQ.1)88C =TM
MOISTRE
IF(BBC.EQ.2)3BC =TS
MOISTRE
IF(TBC.EQ.1)TBC =TM
MOISTRE
IF(TBC.EQ.2)TBC =TS
MOISTRE
IR =1000.
MOISTRE
HED =CL= CHECK= ETS= ET= CI =FN(1) =DIF= CONST= SF(1) =0.0
MOISTRE
X=10. * *( -10.)
MOISTRE
TN(1) =TBC
MOISTRE
INITIALIZE THETA AS CONSTANT WITH DEPTH.
MOISTRE
00 43 J =2,Q
MOISTRE
SF(J) =0.0
MOISTRE
TN(J) =SM
MOISTRE
IF(J.EQ.Q)GO TO 43
MOISTRE
TN(J +1) =SM
MOISTRE
CONTINUE
MOISTRE
TN(Q) =BBC
MOISTRE
IF DESIRED, REINITIALIZE THETA WITH VALUES FROM DATA CARDS.
MOISTRE
DO 15 J =1,Q
MOISTRE
READ 104,TO(J)
MOISTRE
IF(CC.EQ.1)TN(J) =TO(J)
MOISTRE
TH(J) =TN(J)
MOISTRE
CONTINUE
MOISTRE
DO 20 J =1,Q
MOISTRE
Z(J)_0.0
MOISTRE
IF(J.EQ.Q)GO TO 20
MOISTRE
ANT(J)= (TN(J)+TN(J +1))/2.
PROGRAM MOISTRE(INPUT,OUTPUT,TAPE4,TAPE5)
DIMENSION HOR(9),Z(60),MON(30), DATE (30),AMT(30),TME(30),SF(60),
2T0(60),TN(60),FN(60), ANT( 60), K( 60) ,D(60),S(60),E(60),F(60),U(60),
3UH(24),KP3(6),TH(60),AOENT(30)
DIMENSION MEANT1( 12), MEANT2( 12), KA1 (12),KA2(12),K81(12),KB2(12),
1P3(12),P4(12),KP(6),KP1(6)
COMMON /XYZ /IDTE,MONTH,UH, KP3, KP, KPi ,MEANT1,MEANT2,P3,P4,KA1,KA2,K8
11,K82
INTEGER O,P1,P2,Q,APPS,DATE,YEAR, DAY,CROP,TME,AA,BB,CC,ADENT,
1START
REAL K, IR,KSATD,KP,KP1, KP3 ,MEANTI,MEANT2,KA1,KA2,KB1,KB2
C
C
C
C
600
29
C
C
43
C
15
Page 52
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
MOISTRE
MOISTRE
MOISTRE
16
MOISTRE
MOISTRE
MOISTRE
LOOP.
LENGTH
WITHIN
TOTAL
RUN
DAYS
C
MOISTRE
00 32 II =LL,MM
MOISTRE
I =0
MOISTRE
XT= 10.* *( 10.)
MOISTRE
CALL THEOATE(START,II)
MOISTRE
OR
SIXTEENTH
FIRST
ON
BE
RESTARTED
PROGRAM
THIS
ONLY
CAN
NOTE THAT
C
MOISTRE
IF (IDTE.EQ.1.OR.IDTE.E(1.16)11,12
MOISTRE
DO 3 J =1,Q
11
MOISTRE
THAN
0
GREATER
NODE
FOR
J
/DAY
EACH
CM
IS
IN
(U(J))
USE
C----- CONSUMPTIVE
MOISTRE
IF(II.EQ.LL.AND.J.EQ.1)CALL CONUSE(CROP,DELX,J,U(J))
MOISTRE
CALL CONUSEI(CROP,DELX,J,U(J))
MOISTRE
3
CONTINUE
MOISTRE
IF(II.EQ.LL)GO TO 10
MOISTRE
MOISTRE
READ RE -START VARIABLES FOR START OF EACH DAY, EXCEPT DAY ONE OF
C
MOISTRE
THE FIRST YEAR.
C
MOISTRE
12
IF(II.EQ.167.AND.YEAR.EQ.67)GO TO 1
MOISTRE
IF(II.EQ.1.ANO.YEAR.E0.1)GO TO 1
C 12
MOISTRE
8ACKSPACE4
MOISTRE
=1,Q)
,L,HED,ANT(J),CI,ETS,ET,J
IR
CHECK,
READ(4)(TN(J),FN(J),CL,
MOISTRE
MOISTRE
DAY.
OF
EACH
INITIALIZE HEU AT START
C
MOISTRE
IF(II.EQ.TME(L))30,34
1
MOISTRE
30
IF(HED.GT.0.0)HED =HED +AMT(L)
MOISTRE
AMT(L)
IF(HED.LE.0.0)HED=
MOISTRE
L =L +1
MOISTRE
IR =100.
MOISTRE
IR =1000.
MOISTRE
PRINT 102,II,HEO
MOISTRE
MOISTRE
TIME INTERVALS WITHIN EACH DAY LOOP.
C
MOISTRE
34
DO 21 J =1,Q
MOISTRE
TO(J) =TN(J)
21
MOISTRE
C
COMPUTE SIZE OF TIME INTERVAL, DELI.
MOISTRE
I =I +1
MOISTRE
OELTO =DELT
MOISTRE
IF(X.GE.0.i)X= 10. * *( -10.)
MOISTRE
DELT= AMIN1(DELX *0.035 /IR,DELTM)
MOISTRE
IF(DELT.LT.0.00001)OELT =0.00001
MOISTRE
IF( HEO. GT .0.0.AND.KSATO *DELT.GT.HED)OELT =HED /KSATD
MOISTRE
IR= 10. * *( -10.)
MOISTRE
IF(X +DELT.LE.0.1)G0 TO 4
MOISTRE
DELT =0.1
MOISTRE
X =X +DELT
4
MOISTRE
XT =XT +DELT +10. * *( 10.)
MOISTRE
Y= 0.70 *DELT /DELTO
MOISTRE
MOISTRE
C
EXAMINE UPPER BOUNDARY CONDITIONS.
MOISTRE
IF(HED.GT.0.0)GO TO 17
MOISTRE
ARE
FUNCTIONS
REFERENCED.
PLACES
STATEMENT
THREE
OF
C - - - -- NOTE --FIRST
MOISTRE
K(1) =CONOUCT((TO(1) +TO(2))/2.)
MOISTRE
=0.0
IF( (TO(1) +TO(2) /2.).LE.TD)K(1)
MOISTRE
IF(ANT(1).LE.TO)D(1) =0.0
MOISTRE
IF(ANT(1).GT. TO .AND. ANT( 1).LT.0.15)O(1) =DIFUSE1(ANT(1))
MOISTRE
=DIFUSE2(ANT(1))
ANT(
1).LT.0.36)O(1)
AND.
IF(ANT(1).GE.0.15.
MOISTRE
IF(ANT(1).GE.0.36. AND. ANT( 1).LT.0.40)O(1) =DIFUSE3(ANT(1))
MOISTRE
E(1) =1.0
MOISTRE
IF(D(1).LE.0.0)54,55
MOISTRE
F(1) =0.0
54
MOISTRE
GO TO 18
MOISTRE
F(1) =- K(1) *OELX /D(1)
55
20
CONTINUE
DO 16 J =1,Q
CONST= CONST +TN(J)
CONST=CONST-0.5*(TN(1)+TN(Q))
X
Page 53
66
67
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115
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117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
GO TO 18
17
C
TN(1)=TS
NOTE--SECOND OF THREE PLACES STATEMENT FUNCTIONS ARE REFERENCED.
K(1)=CONDUCT((TO(1)+TO(2))/2.)
0(1)=OIFUSE3(ANT(1))
c(1)=0.0
F(1)=TS
COMPUTE
C
18
35
C
C
C
E
ANO F FOR EACH NODE(J)
FROM SURFACE TO DRAIN.
N=1
P1=2
P2=HOR(N)/DELX+1
DO 5 J=P1,P2
COMPUTE SINK TERM FROM VALUE RETURNED FROM SUBROUTINE CONUSE.
S(J)=U(J)*OELT/DELX
IF(J.EQ.Q)GO TO 5
NOTE--THIRD OF THREE PLACES STATEMENT FUNCTIONS ARE REFERENCED.
K(J)=CONOUCT((TO(J)+TO(J+1))/2.)
IF((TO(J)+TO(J+1))/2.0.LE.TO)K(J)=0.0
IF(ANT(J).LE.T0)D(J)=0.0
IF(ANT(J).GT. TD .AND.ANT(J).LT.0.15)O(J)=DIFUSE1(ANT(J))
IF(ANT(J).GE.0.15.AND.ANT(J).LT.0.36)D(J)=DIFUSE2(ANT(J))
IF(ANT(J).GE.0.36.AND.ANT(J).LT.0.40)0(J)=DIFUSE3(ANT(J))
A=(OELT*0(J))/(2.*OELX**2)
C=(OELT*D(J-1))/(2.*DELX**2)
8=1.+A+C
W=A*TD(J+1)+(1.-A-C)*TO(J)+C*TO(J-1)+(K(J-1)-K(J)l*2.*G*
1DELT/(2.*DELX**2)
EXTRACTION OF SINK TERM.
IF(TO(J)-S(J).GT.TD)G0 TO 75
S(J)=T0(J)-TD
W=W-S(J)
Z(J)=Z(J)+(U(J)*OELT-S(J)*DELX)
GO TO 76
75
76
5
W=W-S(J)
ET=ET+S(J)*DELX
E(J)=A/(B-C*E(J-1))
F(J)=(W+C*F(J-1))/(B-C*E(J-1))
CONTINUE
IF(N.GE.0)GO TO 8
N=N+1
P1=P2+1
P2=HOR(N)/DELX+1
GO TO 35
C
8
48
COMPUTE THETA AND FLUX FOR EACH NODE(J) FROM DRAIN TO SURFACE.
J=Q
TN(Q)=BBC
J=Q-1
TN(J)=E(J)*TN(J+i)+F(J)
ANT(J)=(Y*(TN(J+1)-TO(J+1))+Y*(TN(J)-TO(J))+TN(J+1)+TN(J))/2.
IF(ANT(J).GT.TS)ANT(J)=TS
IF(ANT(J).LT.TD)ANT(J)=TD
FN(J)=(K(J)-(D(J)*(TN(J+1)+TO(J+1)-TN(J)-TO(J))/(2.*DELX)))*DELT
FR=FN(J)/DELT
FR=ABS(FR)
IR=AMAX1(IR,FR)
SF(J)=SF(J)+FN(J)
J=J-1
IF(J.GT.0)GO TO 48
CL=CL+FN(Q-1)
ETS=ETS+FN(1)
IF(FN(1).1E.0.0)GO TO 23
CI=CI+FN(1)
HEO=HED-FN(1)
IF(HEO.LE.0.0)HED=0.0
Page 54
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
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MOISTRE
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MOISTRE
MOISTRE
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MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTR£
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
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MOISTRE
MOISTRE
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MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
MOISTRE
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
23
C
6
C
2
C
19
C
C
52
32
99
C
10
9
24
MOISTRE
MOISTRE
MOISTRE
WRITE ON TAPE 5 OR PRINT THETA AND FLUX AT 0.1 DAY INTERVALS.
IF(X.LT.0.1)G0 TO 2
MOISTRE
WRITE( 5)( II, XT, J, TN( J), Z( J), SF(J),CI,CL,HED,ETS,U(J),J =1,Q)
MOISTRE
DO 6 J =1,Q
MOISTRE
Z(J) =0.0
MOISTRE
SF(J) =0.0
MOISTRE
MOISTRE
CHECK TO SEE IF DAY II IS COMPLETED.
MOISTRE
IF(XT.LT.1.0)GO TO 34
MOISTRE
MOISTRE
COMPUTE -CHECK- AS MASS BALANCE CHECK ON LEACHATE.
MOISTRE
CONSTI=0.0
MOISTRE
D0 19 J =1,Q
MOISTRE
MOISTRE
CONST1=CONST1+TN(J)
CONST1=CONSTI-0.5*(TN(1)+TN(Q))
MOISTRE
DIF =( CONSTI- CONST) *DELX
MOISTRE
MOISTRE
CHECK =ETSDIF -ET
MOISTRE
WRITE FINAL VALUES FOR LAST (I) IN DAY (II) AS INPUTS FOR DAY (II+ MOISTRE
WRITE(4)(TN(J),FN(J),CL, CHECK, IR ,L,HED,ANT(J),CI,ETS,ET,J =1,Q)
MOISTRE
MOISTRE
PRINT ONE OF TWO OPTIONS FOR DAILY OUTPUT.
MOISTRE
IF(BB.EQ.1)GO TO 52
MOISTRE
PRINT 124
MOISTRE
PRINT 103
MOISTRE
PRINT 121,II,XT, MONTH ,IOTE,CL,CHECK,ETS,ET,DIF,I
MOISTRE
GO TO 32
MOISTRE
PRINT 124
MOISTRE
PRINT 103
MOISTRE
PRINT 121,II,XT, MONTH ,IDTE,CL,CHECK,ETS,ET,OIF,I
MOISTRE
PRINT 105,(TN(J),J =1,0)
MOISTRE
MOISTRE
CONTINUE
MOISTRE
STOP
MOISTRE
MOISTRE
PRINT RUN PARAMETERS AND INITIAL CONDITIONS.
MOISTRE
IF(AA.EQ.1) 9,12
MOISTRE
PRINT 109
MOISTRE
PRINT 110
MOISTRE
PRINT 122
MOISTRE
PRINT 107
MOISTRE
PRINT 111 ,AA,BB,CC,LL,MM,RBC,TBC,YEAR, CROP,M,APPS,DELX,TS,TM,TD,
MOISTRE
1SM
MOISTRE
PRINT 119
MOISTRE
PRINT 120,(TME(L),MON(L), DATE (L),At1T(L),ADENT(L),L =1,APPS)
MOISTRE
L =1
MOISTRE
PRINT 113
MOISTR£
PRINT 114,(IDENT,HOR(N),N =1,O)
MOISTRE
PRINT 112
MOISTRE
PRINT 105,(TH(J),J =1,0)
MOISTRE
PRINT 108
MOISTRE
PRINT 115
MOISTRE
PRINT 116
MOISTRE
PRINT 117
MOISTRE
IJKL =0
$ DO 24 IJK =1,12
IJKL =IJKL +1
MOISTRE
PRINT 118,IJKL,MEANTI( IJK), P3( IJK),KA1(IJK),K81(IJK),UH(IJKL)
MOISTRE
IJKL =IJKL +1
MOISTRE
PRINT 118,IJKL,MEANT2( IJK), P4( IJK),KA2(IJK),K82(IJK),UH(IJKL)
MOISTR£
ICROP=1 $ PRINT 123,ICROP,( KP(IJK),IJK =1,6)
MOISTRE
ICROP=2 $ PRINT 123,ICROP,(KP1(IJK),IJK =1,6)
MOISTRE
ICROP =3 $ PRINT 123,ICROP,(KP3(IJK),IJK =1,6)
MOISTRE
PRINT 108
MOISTRE
GO TO 12
MOISTRE
MOISTRE
CONTINUE
Page 55
198
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259
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261
262
263
M OIST RE
MOISTRE
MOISTRE
100
MOISTRE
101
MOISTRE
AMOUNT = *F7.2,
DAY NUMBER *,I4, *.
102
MOISTRE
1* CM.
MOISTRE
CL
IDTE
XT
MONTH
7X,*
II
103 FORMAT(
MOISTRE
I*)
OIF
ET
ETS
CHECK
1
MOISTRE
FORMAT(45X,F6.5)
104
MOISTRE
FORMAT(10X,10F12.6)
105
MOISTRE
FORMAT (20X,I2,1X,I2,5X,F10.0,39X,A1)
106
M AP MOIST RE
MM
BBC TBC YEAR CROP
CC
LL
AA
BB
FORMAT( ,6X,*
107
MOISTRE
TM
TO
SM *)
TS
1PS DELX
MOISTRE
FORMAT(iHi)
108
FORMAT(1H1,3X, *PARAMETERS, CONSTANTS, AND INITIAL CONDITIONS USED MOISTRE
109
MOISTRE
1IN THIS REPORT. *)
MOISTRE
RELATIONS
CONDUCTIVITY
AND
DIFFUSIVITY
NOTE
FORMAT( /,4X,*
110
MOISTRE
!HIPS MUST BE INSERTED INTO SOURCE DECK.*, /)
MOISTRE
FORMAT(6X,5I5,2F5.2,4I5,5F5.2)
111
MOISTRE
AT
DEPT
EACH
THETA
CONDITIONS.
MOISTURE
SOIL
FORMAT( /,7X, *INITIAL
112
M O IST RE
1H NODE, READ ACROSS THEN DOWN. *)
MOISTRE
FORMAT( /,7X, *SOIL IDENTIFICATION AND HORIZON DEPTHS.*)
113
MOISTRE
*,F5.1)
DEPTH
*.
=
*,AB,
*IDENTIFICATION
FORMAT(9X,
114
MOISTRE
115 FORMAT( /,7X, *CONSUMPTIVE USE DATA. *)
MOISTRE
BLANEY GRIDDLE DATA TO GET U
FORMAT(9X, *SEMI MONTH
116
MOISTRE
1U IF CROP =3 ONLY. *)
(CM/15 D MOISTRE
KCROP
PCT HV
KCROP
FORMAT(20X, *AVG TEMP
117
MOISTRE
LAYS) *)
MOISTRE
FORMAT( 13X, I2, 7X, F4. 1, 6X ,F4.2,6X,F4.2,7X,F4.2,12X,F5.2)
118
MOISTRE
FORMAT( /,7X, *WATER APPLICATION DAYS, DATES, AND AMOUNTS. *)
119
MOISTRE
=
*,F6.2,*
*AMOUNT
*,I2,7X,
*,I2,*/
*DATE
*,I4,7X,
FORMAT(9X, *DAY NUMBER
120
MOISTRE
SOURCE _ *,A1)
1 CM.
MOISTRE
121 FORMAT (7X,I10,F10.3,2I10,5F10.4,I10)
MOISTRE
*)
CONDITIONS.
PARAMETERS,
AND
BOUNDARY
FORMAT( /,7X, *RUN
122
MOISTRE
FORMAT( /,9X, *PERCENT OF ROOTS IN EACH OF TOP 6 FEET. CROP = *,I1,
123
MOISTRE
16F9.3)
F
MOISTRE
NODE
IF
AT
EACH
DEPTH
THETA
INCLUDING
*DAILY
/,2X,
OUTPUT,
FORMAT(
124
MOISTRE
1RINT OPTION B8 = 1. *)
MOISTRE
ENO
CONUSE
SUBROUTINE CONUSE(CROP,OELX,J,U)
CONUSE
THIS SUBROUTINE RETURNS CONSUMPTIVE USE (U) IN CM /DAY FOR EACH J
C
COMMON /XYZ /IOTE,MONTH,UH,KP3,KP, KPI ,MEANT1,MEANT2,P3,P4,KA1,KA2,KB CONUSE
CONUSE
11,K82
CONUSE
DIMENSION MEANT1( 12), MEANT2( 12), KA1 (12),KA2(12),K81(12),K82(12),
CONUSE
),KP2(6,3),KP3(6),U1(24),UH(24)
6
1P3(12),P4(12),KP(6), KPI(
CONUSE
REAL MEANT1, MEANT2 ,KA1,KA2,KB1,KB2,KP,KP1,KP2,KP3
CONUSE
INTEGER CROP
CONUSE
DATA(ICHECK=0)
CONUSE
CONUSE
READ BLANEY GRIDDLE CONSUMPTIVE USE DATA
C
CONUSE
DO 8 1 =1,12
CONUSE
READ 102 ,MEANTI(I),P3(I),KA1(I),KB1(I)
CONUSE
READ 102 ,MEANT2(I),P4(I),KA2(I),K82(I)
8
CONUSE
ROOT DISTRIBUTIONS TO GO WITH BLANEY GRIDDLE
C
CONUSE
READ 100,( KP(I),I =1,6)
CONUSE
READ 100,(KP1(I),I =1,6)
CONUSE
CARDS
FROM
VALUES
GO
WITH
CONUSE
TO
DISTRIBUTION
C
ROOT
READ
CONUSE
READ 100,(KP3(I),I =1,6)
CONUSE
RETURN
CONUSE
CONUSE
ENTRY CONUSEI
CONUSE
C
COMPUTE DEPTH
CONUSE
0 = DELX *(J 1.)
C ONUSE
CCONVERT DELX (CM) TO DELX (FT)
CONUSE
/30.5
DEL= DELX
CONUSE
C
FORMAT STATEMENTS.
FORMAT(5I5,2F5.0,4I5,5F5.0)
FORMAT(I2,1A8,IF10.0)
FORMAT( /,2X, *WATER APPLIEO.
)
1
READ
Page 56
2
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
C
C
C
9
15
19
C
20
11
12
C
C
1
2
C
3
C
4
C
5
C
6
C
7
C
100
101
102
READ U OFF DATA CARDS IF CROP =3
IF(CROP.NE.3)GO TO 11
IF SECOND SOIL DEPTH NODE, COMPUTE SUBSCRIPT FOR U1(ICOUNT)
IF(J.NE.2)G0 TO 9
ICOUNT= MONTH *2 -0.5
CONVERT INCHES TO CM AND STORE CONUSE VALUES FOR PRINTING (UH)
IF(IDTE.GE.16)ICOUNT= MONTH *2 +0.5
IF(ICHECK.E0.1)GO TO 20
ICHECK =1
DO 15 I =1,6
KP2(I,3) = KP3(I)
DO 19 I =1,24
READ 101,0
U1(I) =U *2.54
UH(I) =U1(I)
OBTAIN U FROM U1 MATRIX
U=U1(ICOUNT)
GO TO 7
DO 12 I =1,6
KP2(I,1) = KP(I)
KP2(I,2) = KP1(I)
I =MONTH
BRANCH ACCORDING TO CROP
GO TO (1,2),CROP
BRANCH ACCORDING TO HALF OF MONTH
IF(IOTE.LE.15)3,4
IF(IOTE.LE.15)5,6
COMPUTE CONSUMPTIVE USE FROM CONSUMPTIVE
U =KA1(I) *(MEANT1(I) *P3(I)/100.) *2.54
COMPUTE CONSUMPTIVE USE FROM CONSUMPTIVE
U= KA2(I) *(MEANT2(I) *P4(I)/100.) *2.54
COMPUTE CONSUMPTIVE USE FROM CONSUMPTIVE
U =KB1(I) *(MEANT1(I) *P3(I)/100.) *2.54
COMPUTE CONSUMPTIVE USE FROM CONSUMPTIVE
U= Kß2( I) *(MEANT2(I) *P4(I) /100.)+`2.54
USE FORMULA
GO TO 7
i
USE FORMULA
$
GO TO 7
USE FORMULA
$
GO TO 7
USE FORMULA
REDUCE CONUSE TO A DAILY BASIS
U=U /15.
ADJUST CONUSE FOR SIZE OF DEPTH INTEERVALS AND ROOT DISTRIBUTION
IF(D.LE.30.5) U = U *KP2(1,CROP) *DEL
U= U *KP2(2,CROP) *DEL
IF(O.GT.30.5.AND.D.LE.61.0)
U=U *KP2(3,CROP) *OEL
IF(D.GT.61.0.AND.O.LE.91.5)
IF(0.GT.91.5.AND.D.LE.122.)
U =U *KP2(4,CROP) *DEL
U =U *KP2(5,CROP) *DEL
IF(D.GT.122..AND.D.LE.153.)
U =U *KP2(6,CROP) *DEL
IF(D.GT.153..ANO.D.LE.183.)
IF(D.GT.183)
U =00
RETURN
FORMAT(6F10.0)
FORMAT(24X,F6.0)
FORMAT(4F10.0)
END
SUBROUTINE THEDATE (K,L)
COMMON /XYZ /IDTE,MONTH,UH,KP3
M =K +L
GO TO 1
IF(M.GE.1.AND.M.LE.31)
IF(M.GT.31.AND.M.LE.59) GO TO 2
GO TO
3
IF(M.GT.59.ANO.M.LE.90)
IF(M.GT.90.AND.M.LE.120) GO TO 4
IF(M.GT.120.ANO.M.LE.151)GO
IF(M.GT.151.ANO.M.LE.181)GO
IF(M.GT.181.AND.M.LE.212)G0
IF(M.GT.212.AND.M.LE.243)G0
IF(M.GT.243.AND.M.LE.273)GO
IF(M.GT.273.ANO.M.LE.304)GO
IF(M.GT.304.AND.M.LE.334)G0
TO 5
TO 6
TO
T
TO
8
TO
9
TO 10
TO 11
Page 57
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
CONUSE
THEDATE
THEDATE
THEDATE
THEOATE
THEDATE
THEDATE
THEDATE
THEOATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
2
3
4
5
6
7
8
9
10
11
12
13
14
15
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
IF(M.GT.334.ANO.M.LE.365)G0 TO 12
i MONTH= 1
IDTE =M
$ MONTH= 2
IDTE =M 31
ñ MONTH= 3
IDTE =M 59
$ MONTH= 4
IDTE =M 90
$ MONTH= 5
IDTE =M 120
$ MONTH= 6
IDTE =M 151
$ MONTH= 7
IDTE =M 181
$ MONTH= 8
IDTE =M 212
$ MONTH= 9
IDTE =M 243
$ MONTH =10
IDTE =M 273
$ MONTH =11
IDTE =M 304
$ MONTH =12
IDTE =M 334
$
á
$
$
$
$
$
$
$
$
$
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
END
INTEGER FUNCTION DAY (K,L,M)
GO TO (1,2,3,4,5,6,7,8,9,10,11,12) M
$ RETURN
OAY =K
$ RETURN
+31
OAY =K
$ RETURN
DAY =K +59
+90
$ RETURN
DAY =K
$ RETURN
DAY =K +120
$ RETURN
DAY =K +151
+181
$ RETURN
DAY =K
$ RETURN
DAY =K +212
$ RETURN
DAY =K +243
$ RETURN
OAY =K +273
$ RETURN
DAY =K +304
$ RETURN
DAY =K -L +334
END
PROGRAM INTFACE (INPUT,OUTPUT,TAPE1,TAPE5)
DIMENSION TN( 60), Z( 60), SF( 60), U( 60 ),MOISIN(12),MOISOUT(11),SEGVOL
1(11)
INTEGER AA,88,CC,Q
REAL MOISIN,MOISOUT
$ MOISIN(1) = 0.0
TEN _ 300.
READ 100,AA,88,CC,Q,IPRINT
DO 1 I =AA,BB
READ (5) ( II, XT, K, TN( J), Z( J), SF(J),CI,CL,HEO,ETS,U(J),J =1,Q)
K = 1
$ SEGVOL(1) = HED
00 4 M= 1,28,3
L
L
L
L
L
L
L
L
L
L
L
K =
4
$
K +
1
SEGVOL(K)
K =
=
2.5 *TN(M) + 5.0 *TN(M +1)
+
5.0*TN(M +2)
+
2.5 *TN(M +3)
2
DO 5 M =4,28,3
K =
5
6
C
C
1
100
105
K
+
1
MOISIN(K) = (SF(M) + SF(M1)) /2.
IF(SF(1).LT.0.0) SF(1) = 0.0
MOISIN(2) = SF(1)
IF(MOISIN(2).GT.0.0) SEGVOL(1) = SEGVOL(1) + MOISIN(2)
MOISIN(12) = SF(30)
00 6 J =2,12
MOISOUT(J 1) = MOISIN(J)
IF(MOO(II,IPRINT).E0.0) PRINT 105, (II,M,M,SEGVOL(J),MOISIN(J),
1MOIS OUT(J),TEN,U(J),J =1,11)
WRITE (1) (II,M,M,SEGVOL(J), MOISIN(J),MOISOUT(J),TEN,U(J),J =1,11)
CONTINUE
STOP
FORMAT(525)
FORMAT(5X,3I5,5E15.3)
END
Page 58
THEOATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
INTFACE
16
17
18
19
20
21
22
23
24
25
26
27
28
29
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
LISTINGS FOR BIOLOGICAL- CHEMICAL PROGRAM
PROGRAM MAIN( INPUT, OUTPUT, TAPE1 = 1002 ,TAPE2 =1002,TAPE3 =1002,TAPE8 =1 MAIN
MAIN
1002,TAPE9 =1002,TAPE10 =1002, PUNCH,TAPE15 =1002,TAPE4= INPUT)
MAIN
MAIN
DIMENSION X(7,25)
MAIN
MAIN
MAIN
COMMON /ABLE/ TITLE( 10), SMONTH, MM, O, IPRINT,JPRINT,INK,IPUNCH,ISTOP,
MAIN
1ITEST, IREADP, IMASS, IADD (25),IORNAP(5),HOR(9),TOTN(99), YEAR
,
MAIN
2AIRR( 9), IRR( 25), TT( 60), FERT( 7), OFERT (3),NORGIN,NFERTIN,NTEMPIN,
MAIN
3ITOT,JTOT,IRTOT,NT
MAIN
COMMON /XX2 /A1,A2,A3,X
MAIN
COMMON /AFG /ENH3,II,LLL
MAIN
COMMON /YYY /START,IDTE,MONTH,I,LL
MAIN
COMMON /XXY/ ICHECK ,ICOUNT,CONV,PK,PKi,CROP,FACT
MAIN
COMMON /XXX /DELX,DELT,MS,WTART,B0(25 ),TEN(25 ),CHECK(25 ),MOISIN
MAIN
1(25 ),CMH2O1(25 ),4OISOUT(25 ),AN03(25 ),ANH3(25 ),URE.A(25 ),ORN
MAIN
2(25 ),CA(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),504(25
3),E5(25 ),C5(25 ),SA5(25 ),XX5(25 ),CASO(25 ),AGSO(25 ),BNH4(25 ), MAIN
4EC(25 ),CN1(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAL(25 ),Q,SRO MAIN
25),CH,CH1,IRERUN,ISWCH,CUMSUM, MAIN
1P, XTRACT,SUMN03,THOR(4),TO,IDAY,U
MAIN
1SUMOUT,REDUCE
MAIN
MAIN
MAIN
INTEGER Q, O, START,CROP,TO,SMONTH,YEAR,TITLE
MAIN
REAL MOISIN,MOISOUT
MAIN
MAIN
DATA (CONV=11.221367)
MAIN
MAIN
MAIN
REWIND 3
$REWIND 8 SREWIND 9 $REWIND 10
MAIN
MAIN
C
SET INITIAL VALUES
MAIN
ICHECK = 0 SCMH2O1(1) = 1.0
MAIN
DO 693 I =1,7
MAIN
DO 693 J =1,25
MAIN
X(I,J) = 1.E +6
693
MAIN
MAIN
C - - -- READ TITLE CARD
MAIN
READ 88,TITLE
MAIN
MAIN
C
READ CONTROL CARDS
MAIN
READ 105,OELX, DELT, XTRACT, CH ,CH1,Ai,A2,REDUCE,PK,PKI,FACT,
MAIN
1LL, MM, O, CROP, TO, NT, IPRINT, JPRINT, INK,IRERUN,IPUNCH,IREADP,ITEST,
MAIN
2START,SMONTH, YEAR ,ISTOP,IMASS,IPRINTI,IPRINTJ
MAIN
MAIN
C
COMPUTE NO, OF TIME INTERVALS PER DAY
MAIN
LLL= 1. /DELT + 0.5
MAIN
IF(IPRINTI.NE.0) CALL PRNT(IPRINTI,IPRINTJ)
MAIN
MAIN
C
READ TEMPERATURE HORIZON DEPTHS
MAIN
(THOR(J),J
107,
=1,TO)
READ
MAIN
MAIN
C
READ COMPONENT HORIZON DEPTHS
MAIN
READ 107,(HOR(J),J =1,0)
MAIN
MAIN
MAIN
C
STORE TEMPERATURE PROFILE DATA ON TAPE 8
MAIN
DO 800 J =1,NT
MAIN
READ 801,(TT(I),I =1,T0)
MAIN
WRITE(8) (TT(I),I =1,TO)
MAIN
800
CONTINUE
MAIN
MAIN
READ IRRIGATION WATER ANALYSIS
C
READ 100, ANH3(i),_ANO3(1),CA(1), ANA (1),AMG(1),HCO3(1),CL(1),CO3(1) MAIN
(
Page 59
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
MAIN
MAIN
MAIN
C- ----STORE TRANSFORMED IRRIGATION WATER ANALYSIS
MAIN
ORN(1)= UREA(1)= SAMT(1) =0.0
MAIN
CALL UNITS1(1)
SAIRR(3) =CA(1)
$AIRR(4) =ANA(i) MAIN
AIRR(1) =ANH3(1)
$AIRR(2) =ANO3(1)
AIRR(5)= AMG(1)
$AIRR(8)= CO3(1)
MAIN
S(AIRR(6) =HCO3(1)
$AIRR(7) =CL(1)
MAIN
AIRR(9)= SO4(1)
MAIN
C
MAIN
COMPUTE TOTAL NUMBER OF COMPONENT HORIZONS
MAIN
Q= HOR(0) /DELX +1.1
MAIN
IF(ITEST.EQ.1)782,783
782
MAIN
READ 784,(CMH2O1(J),MOISIN(J) ,MOISOUT(J),TEN(J),U(J),J =1,Q)
MAIN
MAIN
PRINT HEADING
C
783
MAIN
IF(IRERUN.EQ.0) PRINT 201
MAIN
MAIN
C
SET COUNTERS
MAIN
N =2
$L =1
$Ki = 1
MAIN
MAIN
C
CALL OUTPT TO ZERO INITIAL VALUES
MAIN
CALL OUTPT(K1)
MAIN
IF(IRERUN.EQ.0)22,701
MAIN
MAIN
C
READ INITIAL SOIL ANALYSES
MAIN
22
READ 100,ANH3(1),AN03(1), UREA (1),CA(1),ANA(1),AMG(1),HCO3(1
MAIN
1),CL(1),CO3(1),504(1),EC(1), XX5 (1),CAL(1),B0(1),SAMT(1),CN1(1)
MAIN
PRINT INITIAL SOIL ANALYSES
MAIN
C
MAIN
PRINT 200,L,ANH3(1),ANO3(1), UREA( 1),SAMT(1),CA(1),ANA(1),AMG(1),
MAIN
1HCO3(1),CL(1),CO3(1),SO4(1)
MAIN
MAIN
C
COMPUTE SEGMENT NUMBER OF COMPONENT HORIZON
MAIN
KK =HOR(L) /DELX +1.1
MAIN
MAIN
C
STORE INITIAL SOIL ANALYSES IN PROPER COMPONENT ARRAYS
MAIN
DO 23 J =N,KK
MAIN
$UREA(J) =UREA(1)
ANH3(J)= ANH3(1)
$AN03(J) =AN03(1)
MAIN
CA(J) =CA(1)
$ANA(J) =ANA(1)
$AMG(J)= AMG(1)
MAIN
HCO3(J) =HCO3(1)
$CL(J) =CL(1)
$CO3(J) =CO3(1)
MAIN
SO4(J) =SO4(1)
$EC(J) =EC(1)
$XX5(J) =XX5(1)
CAL(J) =CAL(1)
MAIN
$BD(J) =B0(1)
$SAMT(J)= SAMT(1)
MAIN
CN1(J) =CN1(1)
MAIN
23
CONTINUE
MAIN
MAIN
MAIN
C
CHECK FOR LAST SEGMENT
MAIN
IF(KK.EO.Q)20,21
MAIN
MAIN
C
RESET COUNTERS
HAIN
21
N =KK +1
MAIN
L =L+1
MAIN
GO TO 22
MAIN
PRINT HEADING
MAIN
C
PRINT 202
MAIN
20
MAIN
GO TO 703
701
MAIN
CONTINUE
MAIN
FOR A RERUN, READ FROM TAPES OR FROM CAROS
MAIN
C
MAIN
IF(IREADP.EQ.0)
(3) ICOUNT, NFERTIN, NORGIN, NTEMPIN ,(ANH3(J),ANO3(J),UREA(J) MAIN
1READ
1,CA(J), ANA( J), AMG( J), HCO3( J), CL( J), CO3(J),SO4(J),EC(J),XX5(J),CAL( MAIN
2J), BD( J), SAMT( J), CN1( J), ORN( J), RN( J ),RC(J),E5(J),C5(J),SA5(J),CASO MAIN
MAIN
3(J),AGSO(J),BNH4(J),J =2,Q)
IF(IREADP.NE.0)
MAIN
1,SO4(1)
Page 60
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510
SPACE TAPER FOREWARD THE PROPER NO.
DO 510 I =1,NTEMPIN
READ (8)
522
IF(NFERTIN.EQ.0) GO TO 550
C
511
SPACE TAPE9 FOREWARD THE PROPER NO. OF RECORDS
00 511 I= 1,NFERTIN
READ (9)
550
IF(NORGIN.EQ.0) GO TO 513
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
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MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
C
SPACE TAPE10 FOREWARD THE PROPER NO. OF RECORDS
MAIN
ICOUNT,NFERTIN,NORGIN, NTEMPIN ,(ANH3(J),AN03(J),UREA(J)
1READ 505,
1,CA(J), ANA( J), AMG( J), HCO3( J), CL( J), CO3(J),504(J),EC(J),XX5(J),CAL(
2J), BD( J), SAMT( J), CN1( J), ORN( J), RN( J ),RC(J),E5(J),C5(J),SA5(J),CASO
3(J),AGSO(J),BNH4(J),J =2,Q)
C
SET INITIAL VALUES
703
1 J =2,Q
IF(IRERUN.EQ.0)780,781
ORN(J)= RC(J)= RN(J)= CHECK(J)=0.0
SA5(J)= BNH4(J) =0.0
CMH2O1(J) = XTRACT +BD(J)*DELX
780
DO
EC(J) =EC(J) /1.E5
C
C
781
CALL UNIT CONVERSION SUBROUTINE
CALL UNITSI(J)
PRINT TRANSFORMED DATA
PRINT 200, J,ANH3(J),AN03(J), UREA( J),SAMT(J),CA(J),ANA(J),AMG(J),
IHCO3(J),CL(J),CO3(J),504(J)
IF(IRERUN.EQ.i) CHECK(J) =1.0
i
CONTINUE
C
READ FERTILIZER APPLICATION OATES
READ iO4,ITOT,(IADD(K),K =1,ITOT)
C
READ ORGANIC -N APPLICATION DATES
READ 106,JTOT,(IORNAP(K),K =1,JTOT)
C-
READ IRRIGATION WATER APPLICATION DATES
READ 104,IRTOT, (IRR(K),K =1,IRTOT)
C
STORE FERTILIZER APPLICATIONS ON TAPE
00 802 I =1,ITOT
READ 100,(FERT(J),J =1,7)
WRITE(9) (FERT(J),J =1,7)
CONTINUE
802
C
803
C
16
508
C
9
STORE ORGANIC APPLICATIONS ON TAPE 10
00 803 I =1,JTOT
READ 100,(OFERT(J),J =1,3)
WRITE(10) (OFERT(J)- ,J=1,3)
CONTINUE
SET SEGMENT ONE VALUES EQUAL TO ZERO
ANH3(1) =ÁN03(1) =CÁ(1)= ANA( 1)= AMG( 1 ) =HCO3(1) =UREA(1) =CL(1) =CO3(1)=
1504(1) =0.0
IF(IRERUN.NE.0)508,720
REWIND 8
REWIND 9
REWIND 10
IF(NTEMPIN.EQ.0) GO TO 522
OF RECORDS
MAIN
Page 61
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i37
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512
00 512 I= 1,NORGIN
READ (10)
GO TO 513
720
513
C
C
726
REWIND 8
REWIND 9
REWIND 10
NFERTIN = NORGIN = NTEMPIN = 0
CONTINUE
ISWCH = 1
IF(IPRINTJ.NE.0) CALL PRNT1(IPRINTI,IPRINTJ)
CALL SUBROUTINE TO EXECUTE PROGRAM FOR EACH DAILY TIME INTERVAL
CALL EXECUTE
CHECK FOR ENO OF RUN
IF(MOD(IDAY,365).EQ.0)726,721
IF(YEAR.EQ.ISTOP) GO TO 721
C---- -RESET COUNTERS
ICOUNT = 0 $YEAR
=
YEAR
+
1
ILL = 1
GO TO 720
721
C
502
ENOFILE 2
ENDFILE 15
NTEMPIN =NTEMPIN -1
ICOUNT =-ICOUNT -1
EITHER PUNCH A RERUN DECK OR WRITE RERUN (RESTART) DATA ON TAPE3
IF(IDAY.EQ.365) ICOUNT = NFERTIN = NORGIN = NTEMPIN = 0
IF(IPUNCH.EQ.0) 502,503
REWIND 3
(3) ICOUNT,NFERTIN,NORGIN, NTEMPIN ,(ANH3(0,AN03(J),UREA(J)
WRITE
1,CA(J), ANA( J), AMG( J), HCO3( J), CL( J), CO3(J),SO4(J),EC(J),XXS(J),CAL(
2J),BD(J), SAMT( J), CNI( J), ORN( J), RN( J ),RC(J),E5(J),C5(J),SA5(J),CASO
3(J),AGSO(J),BNH4(J),J =2,Q)
GO TO 561
503
561
88
100
104
105
106
107
200
201
202
505
784
801
C
PUNCH 505,
ICOUNT,NFERTIN,NORGIN, NTEMPIN ,(ANH3(J),ANO3(J),UREA(J)
1,CA(J), ANA( J), AMG( J), HCO3( J), CL( J), CO3(J),SO4(J),EC(J),XX5(J),CAL(
2J),BD(J), SAMT( J), CN1( J), ORN( J), RN( J ),RC(J),E5(J),C5(J),SA5(J),CASO
3(J),AGSO(J),BNH4(J),J =2,Q)
REWIND 2
REWIND 3
STOP
FORMAT(10A8)
FORMAT(16F5.0)
FORMAT (16I5)
FORMAT(11F5.0 /16I5/4I5)
FORMAT(11I5)
FORMAT(5F5.0)
FORMAT(I5,11F10.3)
FORMATE / / / /1X *INITIAL SOIL ANALYSES(MEQ /L OF SOIL EXTRACT)- -(ORG=
lUG /GM OF SOIL)* / /2X *HZN*
*HCO3 *8X *CL
7X*NH3 *7X *NO3 *6X* UREA *7X *ORG*8X*CA*8X *NA*8X *MG *6X
1
1 *7X *CO3 *7X *SO4*)
FORMAT( / /1X *TRANSFORMED SOIL ANALYSES(UG /SEGMENT OF SOIL) * / /2X*SEG
*HCO3 *8X *CL
7X *NH3 *7X *NO3 *6X* UREA *7X *ORG *8X *CA *8X *NA *8X *MG *6X
1*
1 *7X *CO3 *7X *SO4*)
FORMAI(4I5 /,(6Eí3 .5 /6E13.5/6E13.5/6E13.5/E13.5))
FORMAT(5F10.0)
FORMAT(2X,F8.0,7F10.0)
END
SUBROUTINE EXECUTE
SUBROUTINE TO EXECUTE PROGRAM FOR EACH DAILY TIME INTERVAL
Page 62
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
HAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
MAIN
EXECUTE
EXECUTE
EXECUTE
198
199
200
201
202
203
204
205
206
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209
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211
212
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221
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236
237
238
239
240
241
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246
247
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251
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255
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257
258
259
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2
3
4
COMMON/ ABLE/ TITLE( 10), SMONTH, MM, O, IPRINT,JPRINT,INK,IPUNCH,ISTOP,
,
1ITEST, IREAOP, IMASS, IADD (25),IORNAP(5),HOR(9),TOTN(99), YEAR
2AIRR(9),IRR(25),TT(60), FERT(7), OFERT (3),NORGIN,NFERTIN,NTEMPIN,
31T0T,JTOT,IRTOT
COMMON /XX2 /A1,A2,A3,X
COMMON /YYY /START,IDTE,MONTH,I,LL
COMMON/ XXY /ICHECK,ICOUNT,CONV,PK,PKI,CROP
COMMON /AFG /ENH3,II,LLL
COMMON /XXX /DLX,DELT,MS,WTART,8O(25 ),TEN(25 ),CHECK(25 ),MOISIN
1(25 ),CMH2O1(25 ),MOISOUT(25 ),ANO3(25 ),ANH3(25 ),UREA(25 ),ORN
2(25 ),CÁ(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),SO4(25
3),E5(25 ),C5(25 ),SA5(25 ),XX5(25 ),CASO(25 ),AGSO(25 ),BNH4(25 ),
4EC(25 ),CN1(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAL(25 ),Q,SRO
25),CH,CH1,IRERUN,ISWCH,CUMSUM,
1P, XTRACT ,SUMNO3,THOR(+4),TO,IDAY,U
1SUMOUT
(
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
FXECUTE
"CUTE
DIMENSION X(7,25)
INTEGER Q,O,START,CROP,TO,SMONTH,YEAR
REAL MOISIN,MOISOUT
C
C
G
C
3
C
301
C
600
606
601
602
CUTE
¿CUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
LL = STARTING DAY, MM = TERMINATION DAY
EXECUTE
00 4 I = LL,MM
EXECUTE
IF(MOD(I,IMASS).EQ.0) ISWCH = 1
EXECUTE
EXECUTE
STORE DAILY INTERNAL VALUES ON TAPE15
EXECUTE
WRITE (15)
ANH3(J),ANO3(J), UREA( J), CA (J),ANA(J),AMG(J),HCO3(J),CL(J EXECUTE
1(I,J,
EXECUTE
1),CO3(J),SO4(J),EC(J),XX5(J), CAL( J),BD(J),SAMT(J),CN1(J),ORN(J),
EXECUTE
2RN(J),RC(J),E5(J),C5(J), SAS( J) ,CASO(J),AGSO(J),BNH4(J),J =1,0)
EXECUTE
IF(I.E(1.1) REWIND 1
EXECUTE
EXECUTE
CALL SUBROUTINE TO COMPUTE DAY OF MONTH
EXECUTE
CALL THEDATE(START,I,SMONTH,O)
EXECUTE
IDAY = I
EXECUTE
EXECUTE
CHECK FOR FERTILIZER APPLICATION DATE
EXECUTE
DO 3 K =1,ITOT
EXECUTE
IF(I.EQ.IADD(K))301,3
EXECUTE
CONTINUE
EXECUTE
GO TO 5
EXECUTE
EXECUTE
READ FERTILIZER APPLICATIONS FROM TAPE 9
EXECUTE
READ(9) DEPTH, AANH3,AANO3,AUREA,ACA,ASO4,ACO3
EXECUTE
NFERTIN = NFERTIN + 1
EXECUTE
EXECUTE
IF SURFACE APPLICATION, BRANCH TO 600. OTHERWISE GO TO 601
EXECUTE
IF(DEPTH.EQ.0.)6O0,601
EXECUTE
CCC = CONV
EXECUTE
IS = 1
$IDEPTH = 1
EXECUTE
GO TO 602
EXECUTE
IDEPTH = DEPTH /DELX + 1
EXECUTE
IF(IDEPTH.LT.2) IDEPTH = 2
EXECUTE
IS = 2
EXECUTE
CCC = DELX /DEPTH *CONV
EXECUTE
SAVEI = AANH3 *CCC +0.7777
EXECUTE
SAVE2 = AANO3 *CCC *0.2258
EXECUTE
SAVE3 = AUREA *CCC *0.4466
EXECUTE
SAVE4 =ACA *CCC
EXECUTE
SAVE9 =ACO3*CCC
EXECUTE
SAVE10 =ASO4 *CCC
EXECUTE
EXECUTE
DO 302 J = IS,IOEPTH
EXECUTE
Page 63
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41
42
43
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50
51
52
53
54
55
56
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59
60
61
62
63
64
65
66
67
68
69
70
C
C
302
5
C
7
C
C
C
C
303
8
C
17
C
580
581
C
C
C
C
C
400
402
C
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
STORE ACCUM AMOUNTS OF FERTILIZER ADDED
EXECUTE
+
+
+
SAVE3
SAVE2
SAVE1
CUMSUM = CUMSUM
EXECUTE
CUMCA =CUMCA +SAVE4
EXECUTE
CUMC03= CUMCO3 +SAVE9
EXECUTE
+SAVE10
CUMSO4= CUMSO4
EXECUTE
DO 8 K= 1,JTOT
EXECUTE
EXECUTE
DATE
APPLICATION
ORGANIC
-N
FOR
CHECK
EXECUTE
IF(I.EQ.IORNAP(K))7,8
EXECUTE
CONTINUE
EXECUTE
EXECUTE
READ ORGANIC -N APPLICATION
EXECUTE
READ (10) DEPTH,ACNI,SSAMT
EXECUTE
NORGIN = NORGIN + 1
EXECUTE
EXECUTE
VALUES
ANO
STORE
TRANSFORM
EXECUTE
IDEPTH = DEPTHIDELX + 1
EXECUTE
IF(IDEPTH.LT.2) IOEPTH = 2
EXECUTE
DELXIDEPTH*CONV
CCC =
EXECUTE
EXECUTE
DO 303 J =2,IDEPTH
EXECUTE
EXECUTE
STORE ORGANIC -N APPLICATION INTO PROPER ARRAYS
EXECUTE
+
+CCC
SSAMT
SAMT(J) = SAMT(J)
EXECUTE
EXECUTE
STORE ACCUM AMOUNT OF ORGANIC -N ADDED
EXECUTE
SAVE = SSAMT+`CCC30.41ACN1
EXECUTE
CUMSUM = CUMSUM + SAVE
EXECUTE
CN1(J) = ACN1
EXECUTE
GO TO 17
EXECUTE
CONTINUE
EXECUTE
EXECUTE
COMPUTE TEMPERATURE READ -IN DATE
EXECUTE
IF( MOO( I ,7).EQ.O.OR.ICHECK.EQ.0)580,581
EXECUTE
EXECUTE
CALL TEMPERATURE INPUT SUBROUTINE
EXECUTE
CALL TEMP iNTEMPIN = NTEMPIN + 1
EXECUTE
CONTINUE
EXECUTE
IF(MOD(I,INK).EQ.0) K = 2
EXECUTE
EXECUTE
INTERVAL
TIME
FOR
PROGRAM
EACH
ENTER LOOP TO EXECUTE
EXECUTE
EXECUTE
PER
DAY
HERE ILL IS THE NO. OF TIME INTERVALS
EXECUTE
EXECUTE
THE PROGRAM MAY OR MAY NOT CALL ALL OF THE COMPUTATIONAL SUBEXECUTE
ROUTINES FOR EACH INTERVAL
EXECUTE
EXECUTE
EXECUTE
PER
DAY
ONCE
LEAST
AT
ARE
CALLED
ALL CRITICAL ROUTINES
EXECUTE
EXECUTE
DO 10 II =1,LLL
EXECUTE
).EQ.O.ANO.II.EQ.JPRINT)400,401
MOD(
IDAY,
IPRINT
IF(
EXECUTE
PRINT 206.1.11
EXECUTE
PRINT 205
EXECUTE
CONTINUE
EXECUTE
EXECUTE
PROGRAM
FLOW
FROM
MOISTURE
READ INPUT DATA ON TAPEI
IF(ITEST.EQ.0) READ( 1)( I1, I2, I3, CMH2O1 (J),MOISIN(J),MOISOUT(J),T£N EXECUTE
ADD THE FERTILIZER TO THE PROPER ARRAYS
ANH3(J) = ANH3(J) + SAVE1
AN03(J) = AN03(J) + SAVE2
UREA(J) = UREA(J) + SAVE3
CA(J) =CA(J) +SAVE4
CO3(J)= CO3(J) +SAVE9
SO4(J)= SO4(J) +SAVE10
Page 64
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77
78
79
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81
82
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84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
1(J),U(J),J=1,Q)
IF(II.E0.1.AND.CMH2O1(1).GT.0.0)790,795
C
790
C
793
C
CHECK TO SEE IF THIS IS AN IRRIGATION DAY
00 792 18 = 1,IRTOT
IF(I.EQ.IRR(L8))793,792
ENTER ROUTINE TO ADO IRRIGATION WATER COMPONENTS
SSAVE2=AIRR(2)*CMH2O1(1)
SAVE1=AIRR(1)*CMH2O1(1)
$SAVE5=AIRR(4)*CMH2O1(1)
SAVE4=AIRR(3)*CMH2O1(1)
$SAVE7=AIRR(6)*CMH2O1(1)
SAVE6=AIRR(5)*CMH2O1(1)
$SAVE9=AIRR(8)*CMH2O1(1)
SAVE8=AIRR(7)*CMH2O1(1)
SAVE10=AIRR(9)*CMH2O1(1)
áAN03(i)=AN03(1)+SAVE2
ANH3(1)=ANH3(1)+SAVE1
$ANA(1)=ANA(1)+SAVE5
CA(1)=CA(1)+SAVE4
$HCO3(1)=HCO3(1)+SAVE7
AMG(1)=AMG(1)+SAVE6
$CO3(1)=CO3(1)+SAVE9
CL(1)=CL(1)+SAVE8
SO4(1)=SO4(1)+SAVEID
STORE ACCUM AMOUNTS OF COMPONENTS
SCUMCA=CUMCA+SAVE4
CUMSUM=CUMSUM+SAVEI+SAVE2
$CUMAMG=CUMAMG+SAVE6
CUMANA=CUMANA+SAVE5
áCUMCL=CUMCL+SAVE8
CUMHCO3=CUMHCO3+SAVE7
ñCUMSO4=CUMSO4+SAVE10
CUMC03=CUMC03+SAVE9
GO TO 795
792
795
CONTINUE
CONTINUE
C
CALL COMBINE SUBROUTINE
CALL COMBINE(IDAY,IPRINT,JPRINT)
CONTINUE
CONTINUE
RETURN
10
4
205
206
FORMAT(
1X *PREDICTED AMOUNTS(UG /SEGMENT OF SOIL) -- (SEGVOL =CC NATE
1R/SEG SOIL)* / /2X*SEG*
*HCO3 *8X *CL
7X *NH3 *7X *NO3 *6X* UREA *7X *ORN *8X *CA *8X *NA *8X *MG *6X
1
1 *7X *CO3 *7X *SO4* 6X *ENH4 *4X *SEGVOL *)
FORMAT( / /IX*OAY= *,I4,10X *TIME INTERVAL= *,I4)
ENO
SUBROUTINE COMBINE(IDAY,IPRINT,JPRINT)
C
C
THIS SUBROUTINE CALLS THE COMPUTATIONAL SUBROUTINES AND ASSEMBLES
THEIR DELTA VALUES
COMMON /SABLE /SUMS(3)
COMMON /EEE /PSUM,DIFNH4,0IFN03,TPLANT
COMMON /XXY/ICHECK,ICOUNT
COMMON /YYY /START,IDTE,MONTH,III,LL
COMMON /AFG /ENH3,II,LLL
COMMON /XXX /OELX,DELT,MM,WTART,BD(25 ),TEN(25 ),CHECK(25 ),MOISIN
1(25 ),CMH2O1(25 ),MOISOUT(25 ),AN03(25 ),ANH3(25 ),UREA(25 ),ORN
2(25 ),CA(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),SO4(25
3),E5(25 ),C5(25 ),SA5(25 ),XX5(25 ),CASO(25 ),AGSO(25 ),BNH4(25 ),
4EC(25 ),CN1(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAL(25 ),Q,CRO
1P, SPACE (36),ISWCH,CUMSUM,SUMOUT,REDUCE
COMMON / GIRL/ UREAI, UREA2, DNH31, 0NH32 ,DN031,0N032,CA1,ANAI,AMG1,
1HC031,CL1,C031,S041,KKK
DIMENSION CONVERT( 25), EXNH3( 25 ),EXCA(25),EXANA(25),EXAMG(25),
1OELN03( 25), DELNH3( 25), DELORGN( 25), DELUREA (25),EXHCO3(25),EXC03(25)
2, EXSO4( 25), EXCL( 25), EXBNH4( 25), FLN03 (25),FLNH3(25),FLUREA(25),FLCA
3( 25), FLANA( 25), FLAMG( 25), FLHCO3( 25 ),FLCL(25),FLC03(25),FLSO4(25),
4PLN03( 25), PLNH4( 25), DELBNH4( 25), ANETI (25),ANET2(25),ANET3(25),ADOI
5T( 25) ,ADDITI(25),OELRN(25),DELRC(25)
Page 65
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
EXECUTE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
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163
164
165
166
167
168
169
170
171
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173
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175
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
COMBINE
COMBINE
COMBINE
IFACT = REDUCE
COMBINE
ISET = IFACT + 2 4F = 1.0
COMBINE
IF(II.EQ.LLL) K =2
COMBINE
COMBINE
C
COMPUTE DELTA VALUES FOR EACH SOIL SEGMENT
COMBINE
DO 1 I =2,Q
50
COMBINE
COMBINE
CALL SHUT -OFF SUBROUTINE
C
CALL CHK(L1,L2,13,I,EXNH3(I), EXCA( I),EXANA(I),EXAMG(I),DELN03(I), COMBINE
COMBINE
10ELNH3 (I),OELORGN(I),DELUREA(I))
COMBINE
IF(II.EQ.1.OR.ISET.LE.IFACT)3,4
COMBINE
3
L1 =L2 =L3 =0
COMBINE
4
CONTINUE
COMBINE
COMBINE
C
SET A UNIT CONVERSION CONSTANT
COMBINE
CONVERT(I) = OELX *BD(I)
COMBINE
COMBINE
C
CALL THE EXCHANGE SUBROUTINE
IF(L1.E(A.0) CALL XCHANGE(I, EXNH3( I) ,EXCA(I),EXANA(I),EXAMG(I),EXHC COMBINE
COMBINE
103( I), EXCO3 (I),EXS04(I),EXCL(I),EXBNH4(I))
IF(L1.NE.0) EXNH3( I)= EXCA( I) = EXANA( I) = EXAMG(I) =EXHCO3(I) =EXC03(I) = COMBINE
COMBINE
1EXSO4(I)= EXBNH4(I)= EXCL(I) =0.0
COMBINE
COMBINE
C
CALL THE NITROGEN TRANSFORMATION SUBROUTINE
IF(L2.EQ.0) CALL TRNSFM(I, CONVERT( I ),DELUREA(I),DELORGN(I),DELNH3( COMBINE
COMBINE
1I), DELN03( I), DELBNH4 (I),DELRN(I),DELRC(I),II)
COMBINE
COMBINE
C
CALL THE FLOW SUBROUTINE
CALL FL( I, FLN03( I), FLNH3 (I),FLUREA(I),FLCA(I),FLANA(I) COMBINE
COMBINE
1, FLAMG( I), FLHCO3 (I),FLCL(I),FLC03(I),FLSO4(I))
COMBINE
IF(II.NE.1) GO TO 20
COMBINE
IF(ISET.LE.IFACT) GO TO 20
COMBINE
COMBINE
C
CALL THE PLANT NUTRIENT UPTAKE SUBROUTINE
COMBINE
IF( IDTE. EQ .1.OR.IDTE.EQ.15.OR.IDAY.EQ.LL) CALL UPTAKE(I,PLNO3(I),
COMBINE
1PLNH4(I),DELT,OELX)
COMBINE
20
CONTINUE
COMBINE
COMBINE
C
TEST FOR NEGATIVE RATE AND ZERO MASS
COMBINE
IF( DELNH3( I). LT.0.0.AND.ANH3(I).EQ.0.0)60,61
60
COMBINE
DELBNH4(I) = DELBNH4(I) + DELNH3(I) /14.0E6
COMBINE
DELNH3(I) = 0.0
COMBINE
61
CON = AN03(I) /CMH2O1(I)
COMBINE
CON/ = ANH3(I) /CMH2O1(I)
COMBINE
COMBINE
C
TEST FOR LOW NO3 CONCENTRATION
COMBINE
IF(CON.LT.O.2)62,63
COMBINE
62
ADDIT(I) = 0.0
COMBINE
GO TO 64
COMBINE
63
ADDIT(I) = PLN03(I)
COMBINE
COMBINE
C--- --TEST FOR LOW NH4 CONCENTRATION
COMBINE
64
IF(CONI.LT.0.2)65,66
COMBINE
65
ADDITI(I) = 0.0
COMBINE
GO TO 67
COMBINE
66
ADDIT /(I) = PLNH4(I)
COMBINE
67
CONTINUE
COMBINE
COMBINE
C
COMPUTE NET CHANGES FOR NH4, UREA, AND NO3
COMBINE
ANETI(I) = OELNH3(I) + FLNH3(I) + EXNH3(I) + ADDITI(I)
COMBINE
ANET2(I)= DELUREA(I) + FLUREA(I)
COMBINE
ANET3(I)= OELN03(I) + FLN03(I) + ADOIT(I)
COMBINE
COMBINE
-TEST TO DETERMINE IF SEGMENT ONE IS BEING CONSIDERED
INTEGER Q
C-
Page 66
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83
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91
92
93
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77
1
IF(KKK.EQ.1)77,1
SNH31 =DNH31 $SNO31 =0N031 $SREA1 =UREA1 $SA1 =CAt $SNA1 =ANA1
SMGI =AMG1 $SC031 =HC031 SSLI =CL1 $5031 =C031 $R041 =SO41
CONTINUE
C
TEST TO DETERMINE IF ADDITIONAL TIME STEPS ARE BEING USED
IF(ISET.LE.IFACT) GO TO 16
C
TEST TO DETERMINE IF MASS IN SYSTEM WILL BE EXCEEDED
00 5 I =2,Q
IF(ANH3(I) + ANET1(I).LT.0.0) GO TO 14
IF(UREA(I) + ANET2(I).LT.0.0) GO TO 14
IF(ANO3(I) + ANET3(I).LT.0.0) GO TO 14
5
CONTINUE
GO TO 16
C
14
C
16
USE SMALLER TIME STEPS IF NECESSARY
$F = IFACT
ISET = 1
UPDATE THE MASSES
DO 6 I =2,Q
ANH3(I) = ANH3(I)
AN03(I) = AN03(I)
IN STORAGE
+
+
ANET1(I) /F
ANET3(I) /F
$UREA(I) = UREA(I) + ANET2(I) /F
SCA(I) = CA(I) + FICA(I) /F + EXCA(
1I)
ANA(I) = ANA(I) + FLANA(I) /F + EXANA(I) $ AMG(I) = AMG(I) + FLAMG(I
/F +EXAMG(I)
HCO3(I) = HCO3(I) + FLHCO3(I) /F + EXHCO3(I)
SCL(I) = CL(I) + FLCL
1(I) /F + EXCL(I)
$SO4(I) = SO4(I) + FLSO4(
CO3(I) = CO3(I) + FLC03(I) /F + EXC03(I)
1I) /F + EXSO4(I)
BNH4(I) = BNH4(I) + EXBNH4(I) + OELBNH4(I) /F %ORN(I) =ORN(I) +DELORG
IN(I) /F $RN(I) =RN(I) +DELRN(I) /F SRC(I) =RC(I) +DELRC(I) /F
IF(I.EQ.Q) 30,31
1)
C
30
C
31
36
37
KEEP TRACK OF TOTAL -N LEACHED FROM SYSTEM
SUMOUT = SUMOUT +(0N032 + DNH32 + UREA2) /F
SUMS(1) = SUMS(1) + DN032 /F
SUMS(2) = SUMS(2) + DNH32 /F
SUMS(3) = SUMS(3) + UREA2 /F
UPDATE MASSES CONTAINED ON SOIL SURFACE
IF(I.E(1.2)36,37
ANH3(1) = ANH3(1) - SNH31 /F$AN03(1) = AN03(1) - SNO31 /F
UREA(I) = UREA(1) - SREA1 /F$CA(1) = CA(1) - SAi /F
ANA(i) = ANA(1) - SNA1 /F$AMG(1) = AMG(1) - SMG1 /F
HCO3(1) = HCO3(1) - SC031 /F $CL(1) = CL(i) - SL1 /F
CO3(1) = CO3(1) - S031/F$SO4(1) = SO4(i) - R041/F
CONTINUE
C
CHECK AND CORRECT FOR ANY NEGATIVE VALUES
IF(BNH4(I).LT.0.0) BNH4(I) = 0.0
IF(AN03(I).LT.0.0) AN03(I) = 0.0
IF(ANH3(I).LT.0.0) ANH3(I) = 0.0
IF(UREA(I).LT.0.0) UREA(I) = 0.0
IF(ORN(I).LT.0.0) ORN(I) = 0.0
IF(CA(I).LT.0.0) CA(I) = 0.0
IF(ANA(I).LT.0.0) ANA(I) = 0.0
IF(AMG(I).LT.0.0) AMG(I) = 0.0
IF(HCO3(I).LT.0.0) HCO3(I) = 0.0
IF(CL(I).LT.0.0) CL(I) = 0.0
IF(CO3(I).LT.0.0) CO3(I) = 0.0
IF(SO4(I).LT.0.0) SO4(I) = 0.0
C
KEEP TRACT OF PLANT UPTAKE OF N
Page 67
COMBINE
COMBINE
COMBINE
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COMBINE
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COMBINE
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COMBINE
COMBINE
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COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
COMBINE
95
96
97
98
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100
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104
105
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112
113
114
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17
18
25
C
C
2
6
C
C
C
100
C
C
C
C
C
C
COMBINE
COMBINE
COMBINE
COMBINE
L1 =L2 =L3 =0
COMBINE
GO TO 25
COMBINE
$PL2 = ADDITI(I)
PLi = ADDIT(I)
COMBINE
TPLANT = TPLANT + PLNH4(I) + PLN03(I)
COMBINE
PSUM = PSUM + PL1 + PL2
COMBINE
IF(ANH3(I).EQ.0.0) DIFNH4 = DIFNH4 + PL2
COMBINE
IF(AN03(I).EQ.0.0) DIFNO3 = DIFNO3 + PL1
COMBINE
IF(ISET.LT.IFACT) GO TO 6
COMBINE
IF(MOD(IOAY,IPRINT).E Q.O.AND.II.EQ.JPRINT)2,6
COMBINE
COMBINE
PRINT VALUES FOR THE COMPONENTS (UG /SEGMENT) ANO SEGMENT VOLUMES
COMBINE
(ML)
COMBINE
VNH3 = BNH4(I)}14.0E6 *CONVERT(I)
COMBINE
PRINT 100,I,ANH3(I),AN03(I), UREA (I),ORN(I),CA(I),ANA(I),AMG(I),
COMBINE
IHCO3( I), CL( I),CO3(I),504(I),VNH3,CMH2O1(I)
COMBINE
CONTINUE
COMBINE
ISET = ISET + 1
COMBINE
IF(ISET.LE.IFACT) GO TO 50
COMBINE
COMBINE
CALL SUBROUTINE TO OUTPUT LEACHATE VALUES
COMBINE
CALL OUTPT(K)
COMBINE
COMBINE
CALL MASS BALANCE ROUTINE FOR NITROGEN
COMBINE
IF(ISWCH.EQ.1.AND.II.EQ.JPRINT) CALL MCHECK
COMBINE
COMBINE
COMBINE
RETURN TO SUBROUTINE EXECUTE
COMBINE
RETURN
COMBINE
COMBINE
FORMAT(I5,13F1Q.3)
COMBINE
COMBINE
END
SUBROUTINE TRNSFM(J1, CONVERT, OELUREA ,DELORGN,DELNH3,DELNO3,OELBNH4 TRNSFM
TRNSFM
1,DELRN,DELRC,II)
TRNSFM
TRNSFM
THIS IS THE NITROGEN TRANSFORMATION SUBROUTINE
TRNSFM
TRNSFM
TRNSFM
COMMON /AFG /ENH3,II1,LLL
TRNSFM
COMMON /XXX /DELX,DELT,MM,START,BO(25 ),TEN(25 ),CHECK(25 ),MOISIN
TRNSFM
1(25 ),CMH2O1(25 ),MOISOUT(25 ),ANO3(25 ),ANH3(25 ),UREA(25 ),ORN
2(25 ),CA(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),504(25 TRNSFM
3),E5(25 ),C5(25 ),SÁ5(25 ),XX5(25 ),CASO(25 ),AGSO(25 ),BNH4(25 ), TRNSFM
4EC(25 ),CNR(25 ),AOR (25 ),RN(25 ),RC(25 ),TEM(25 ),CS (25 ),Q,CRO TRNSFM
TRNSFM
1P, XTRACT, SUMNO3, THOR( 4),TO,IOAY,U3(25),CH,CH1,IRERUN
TRNSFM
TRNSFM
INTEGER CROP,TO,Q
TRNSFM
DIMENSION AMT (130,4),R(130,5),C(5),B1(5),T( 1 ),82(5),A(5),W( 1), TRNSFM
TRNSFM
1B3(5),SAMT(2,4),CN1(1),CN( 130), AMTRC (130),AMTRN(130),AAMTRC(2),
TRNSFM
2AAMTRN(2),OAMT(2,5),AAMT(2,4)
TRNSFM
TRNSFM
TRNSFM
ESTABLISH A SET OF CONSTANTS
TRNSFM
DATA((C(L),L =1,4)= 413. 1,. 8917,4.639,0.),((B1(L),L =1,4) = -155.6,
TRNSFM
1 -. 002156,. 001621 , -3.223E- 15),((82(L),L= 1,4) =- 152.8, -.02696,.2384,
TRNSFM
2 +1.512),((B3(L),L =1,4) =0.0,.3916,- 2.151,- 4.900E -03)
TRNSFM
TRNSFM
CONVERT TO STORAGE LOCATIONS AND UNITS NEEDED IN THE SUBROUTINE
TRNSFM
COMPONENT UNITS IN THIS ROUTINE ARE EXPRESSED IN UG /SEGMENT SOIL
TRNSFM
TEMPERATURE UNITS ARE DEGREES C
TRNSFM
MOISTURE UNITS ARE BARS
TRNSFM
IF(ISET.LE.IFACT)17,18
$PL2 = ADOITI(I) /IFACT
PL1 = ADDIT(I) /IFACT
TPLANT = TPLANT + PLNH4(I) /IFACT + PLN03(I) /IFACT
Page 68
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6000
C
C
612
N
C
C
N
C
310
N
C
801
C
C
600
N
C
311
N
C
615
N
C
616
C
C
N
N
C
C
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
SET INITIAL VALUES
TRNSFM
M =1
TRNSFM
X = ILL
TRNSFM
K =1
TRNSFM
TRNSFM
ENTER LOOP TO DO COMPUTATIONS FOR EACH TIME INTERVAL
TRNSFM
DO 611 I =1,K
TRNSFM
TRNSFM
ROUNTNE
ENTER UREA
TRNSFM
PRESENT AT THE START OF A DAY
DETERMINE`THE AMOUNT OF UREA
TRNSFM
TRNSFM
L =1
TRNSFM
AMT(1,L) = SAMT(M,L) +AAMT(M,L)
TRNSFM
TRNSFM
CHECK FOR ZERO AMOUNT OF UREA
TRNSFM
IF(AMT(I,1).EQ.0.0) 310,801
TRNSFM
TRNSFM
SET RATE EQUAL TO ZERO FOR ZERO AMOUNT OF UREA
TRNSFM
R(I,L) = 0.0
TRNSFM
GO TO 311
TRNSFM
TRNSFM
HYDROLYSIS
COMPUTE RATE OF UREA
TRNSFM
R(I,L) = C( L)+( B1( L)+ ALOG10( T (M))) +(B2(L)*ALOGi0(AMT(I,L)))
TRNSFM
TRNSFM
_
-AMT(I,L)
R(I,L)
5.0)
IF(R(I,L).GE.
TRNSFM
CORRECT RATE FOR LOW TEMPERATURES
TRNSFM
IF(T(M).LE.10.0) R(I,L) = R(I,L) *ALOG10(T(M)) /4.0
TRNSFM
TRNSFM
ADJUST RATE FOR LENGTH OF TIME INTERVAL
TRNSFM
R(I,L) = R(I,L) /X
TRNSFM
PRESENT AT THE START OF NEXT TIME INTER TRNSFM
DETERMINE AMOUNT OF UREA
TRNSFM
AMT(I +1,L) =AMT(I,L) +R(I,L)
TRNSFM
TRNSFM
CHECK FOR NEGATIVE AMOUNTS OF UREA
TRNSFM
IF(AMT(I+1,L))615,616,616
TRNSFM
AMT(I +1,L) =0.0
TRNSFM
TRNSFM
ROUTINE
ENTER ORGANIC
TRNSFM
L =2
TRNSFM
TRNSFM
DAY
ADDED
EACH
ORGANIC
OF
AMOUNT
COMPUTE THE
TRNSFM
IF(CN1(M).EQ.0.0) OAMT(M,L) = 0.0
TRNSFM
OAMT(M,L) = 0.4 /CN1(M) +SAMT(M,2)
IF(CN1(M).GT.0.0)
TRNSFM
PRESENT TRNSFM
COMPUTE THE AMOUNTS OF AMMONIA N, ORGANIC N, AND NITRATE
TRNSFM
AT THE START OF A DAY
TRNSFM
TRNSFM
AMT(1,L) = OAMT(M,L) + AAMT(M,2)
TRNSFM
AMT(113) = SAMT(M,3) + AAMT(M,3)
AAMT(1,1) = UREA(J1)
AAMT(1,2) = ORN(J1)
ENH3 = 9NH4(J1)*CONVERT414.0E6
AAMT(1,3) = ANH3(J1) + ENH3
AAMT(1,4) = AN03(J1)
SAMT(1,2) = AOR(J1)
AAMTRN(1) = RN(J1)
AAMTRC(1) = RC(J1)
CN1(1) = CNR(J1)
T(1) = TEM(J1)
W(1) = ABS(TEN(J1)) /1030.
SAMT (1,1)= SAMT(1,3) =SAMT(1,4) =0.0
SAMT(1,2) = SAMT(1,2) /CONVERT
DO 6000 J =1,4
AAMT(1,J) = AAMT(1,J)1CONVERT
N
N
Page 69
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TRNSFM
TRNSFM
TRNSFM
TRNSFM
ANO
RESIDUE-C
OF
RESIDUE-N
AMOUNTS
INITIAL
THE
C
COMPUTE
TRNSFM
IF(CN1(M).EQ.0.0) AMTRN(1) = AAMTRN(M)
TRNSFM
+
AAMTRN(M)
IF(CN1(M)GT.0.0) AMTRN(1) = 0.4/CN1(M)*SAMT(M,2)
TRNSFM
AAMTRC(M)
AMTï2C(1)
=
IF(CN1(M).EQ.0.0)
TRNSFM
IF(CN1(M)GT.0.0) AMTRC(1) = 0.4*SAMT(M,2) + AAMTRC(M)
TRNSFM
IF(AMTRC(1).LE.0.0.OR.AMTRN(1).LE.0.0)2002,2003
TRNSFM
2002 CN(1) = 10.0
TRNSFM
GO TO 2004
TRNSFM
TRNSFM
COMPUTE INITIAL C/N RATIO
C
TRNSFM
2003 CN(1) = AMTRC(1)/AMTRN(1)
TRNSFM
TRNSFM
MAKE CONSTANT ADJUSTMENTS ACCORDING TO C/N RATIO
C
TRNSFM
82(3) = 4.5
2004 IF(CN(I).LT.23.0)
TRNSFM
B3(2) = 1.6
IF(CN(I).LT.23.0)
TRNSFM
83(2) _ .7832
IF(CN(I).GE.23.0)
TRNSFM
=
.0008
81(3)
IF(CN1I).GE.23.0)
TRNSFM
B2(3) _ .0002384
IF(CN(I).GE.23.0)
TRNSFM
B3(3) _ -2.1
IF(CN(I)Gc.23.0)
TRNSFM
TRNSFM
COMPUTE RATE OF MINERALIZATION - IMMOBILIZATION
C
751 R(I,L)=C(L)+(Bi(L)*T(M))+(82(L)*AMT(I,L))+(63(L)*ALOG10(AMT(I,3))) TRNSFM
TRNSFM
TRNSFM
CORRECT RATE FOR LOW TEMPERATURES
C
TRNSFM
R(I,L) = R(I,L)*ALOG10(T(M))/4.0
IF(T(M).LE.10.0)
TRNSFM
TRNSFM
CORRECT RATE FOR LOW MOISTURES
C
TRNSFM
=
R(I,L)/ALOG10(W(M))*0.3
IF(W(M).GE.10.0) R(I,L)
TRNSFM
IF(R(I,L).LT.0.0.ANO.CN(I).GE.23.0) R(I,L) = 0.0
TRNSFM
IF(R(I,L).LT.O.Q.AND.CN(I).LT.23.0) R(I,L) = ABS(R(I,L))
TRNSFM
TRNSFM
CORRECT RATE FOR C/N RATIO
C
TRNSFM
2.518)
R(I,L) = R(I,L)*(1.848*ALOG10(CN(I))
TRNSFM
IF(R(I,L))802,803,804
TRNSFM
802 IF(AMT(I,L).LT.AÉS(fi2(I,L))) R(I,L) _ -AMT(I,2)
TRNSFM
GO TO 803
TRNSFM
804 IF(AMT{I,3).LT.R(I,L)) R(I,L) = AMT(I,3)
TRNSFM
TRNSFM
FOR
OF
TIME
INTERVAL
LENGTH
ADJUST RATE
C
TRNSFM
803 R(I,L) = R(I,L)/X
TRNSFM
=0.0001
IF(AMT(I,2).EQ.0.0) AMT(I,2)
TRNSFM
TRNSFM
CHECK FOR ZERO AMOUNT OF NITRATE-N
C
TRNSFM
307,
308
IF (AMT(I,4). EQ. 0.0)
TRNSFM
307 R(I,5) = 0.0
TRNSFM
GO TO 309
TRNSFM
TRNSFM
C
COMPUTE RATE OF NITRATE-N IMMOBILIZATION
308 R(I,5) = (81(4) * EXP(T(M)))+ (82(4) * T(M)/(AMT(I,2)**2))+(B3(4)* TRNSFM
TRNSFM
1(T(M)*(AMT(I,2)AMT(I,4)))/AMT(I,2))
TRNSFM
IF(CN(I).LE.10.0)1,5
TRNSFM
R(I,5) = R(I,5)*0.1
TRNSFM
R(I12) = R(I,2)*0.005
TRNSFM
5
CONTINUE
TRNSFM
TRNSFM
CORRECT RATE FOR LOW TEMPERATURES
C
TRNSFM
IF(T(M).LE.10.0) R(I,L) = R(I,L)*ALOG10(T(?i))/4.0
TRNSFM
TRNSFM
CORRECT RATE FOR LOW MOISTURES
G
TRNSFM
IF(W(M).GE.10.0) R(I,L) = R(I,L)/ALOG10(W(M))*0.3
TRNSFM
809 IF(AMT(I,4).LT.R(I,5)) R(I,5) = AMT(I,4)
TRNSFM
IF(R(I,5).LE.0.0) R(I,5) = ABS(R(I,5))
TRNSFM
AMT(1,4) = SAMT(M,4) + AAMT(M,4)
IF(AMT(I,3).EQ.0.0) AMT(I,3) = 0.0001
Page 10
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C
ADJUST RATE FOR LENGTH OF TIME INTERVAL
808 R(I,5) = R(I,5)/X
C
ENTER BRANCH ACCORDING TO C/N RATIO
309 IF(CN(I).LE.80.0.AND.CN(I).GT.23.0)2000,2001
C
COMPUTE AMOUNT OF RESIDUE-C AT T + 1
2000 AMTRC(I+1) = AMTRC(I) - (30.*(R(I,L)+R(I,5)))
C
C
COMPUTE AMOUNT OF RESIDUE-N AT T + 1
AMTRN(I+1) = AMTR.N(I)
IF(AMTRC(I+1).L£.0.0.OR.AMTRN(I+1).LE.0.0) GO TO 1030
GO TO 1031
COMPUTE AMOUNTS OF RESIDUEN ANO R:ESIDUE-C AT T + 1
= AMTRC(I) - (30.*(ABS(R(I,L)-R(I,5))l)
AMTRN(I+1) = AMTRN(I) - ABS(:R(I,L))
IF(AMT RC(I+1).LE.0.0.OR.AMTRN(I+1).LE.0.0) GO TO 1030
2001 AMTRC.(I+i)
GO TO 1031
1030 CN(I+1) = 10.0
GO TO 1022
C
COMPUTE C/N RATIO AT T + 1
1031 CN(I+1) = AMTRC(I+1)/AMTRN(I+1)
1022 IF(AMTRC(I+1).LE.0.0) AMTRC(I+1) = 0.0
IF(AMTRN(I+1).LE.0.0) AMTRN(I+1) = 0.0
If(I.EQ.K) AAMTRN(M+1) = AMTRN(I+1)
IF(I.EQ.K) AAMTRC(M+1) = AMTrRC(I+1)
AMT(I+1,L)=AMT(I,L)+R(I,L)+R(I,5)
IF(AMT(I+1,L))620,621,621
620 AMT(I+1,L)=0.0
C
C
C
C
G
G
C
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSF M.
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
T RNSFM
TRNSFM
ENTER AMMONIA-N ROUTINE
TRNSFM
TRNSFM
IF(AMT(I,4).EQ.0.0) AMT(I,4)=0.0001
TRNSFM
TRNSFM
CHECK FOR ZERO AMOUNT OF AMMONIA-N
TRNSFM
IF(AMT(I,3).c(1.0.0) 305, 753
TRNSFM
305 R(I,L) = 0.0
TRNSFM
GO TO 306
TRNSFM
TRNSFM
COMPUTE RATE OF NITRIFICATION
753 R(I,L)=C(L)+(B1(L)'FT(M)*AMT(I,3))+(B2(L)*ALOG10(AMT(I,3)))+(B3(L)* TRNSFM
TRNSFM
1ALOG10(AMT(I,4)))
TRNSFM
TRNSFM
CORRECT RATE FOR LOW TEMPERATURES
TRNSFM
R(I,L) = R(I,L)*ALOG10(T(M))/4.0
IF(T(M).LE.10.0)
TRNSFM
TRNSFM
CORRECT RATE FOR LOW MOISTURES
TRNSFM
IF(W(M).GE.10.0) R(I,L) = R(I,L)1ALOG10(W(M))*0.3
TRNSFM
IF(R(I,L))815,816,817
TRNSFM
R(I,L) = -AMT(I,4)
815 IF(AMT(I,4).LT.ABS(R(I,L)))
TRNSFM
GO TO 816
TRNSFM
R(I,L) = AMT(I,3)
817 IF(AMT(I,3).LT.R(I,L))
TRNSFM
TRNSFM
ADJUST RATE FOR LENGTH OF TIME INTERVAL
TRNSFM
816 R(I,L) = R(I,L) /X
TRNSFM
TRNSFM
COMPUTE AMOUNT OF AMMONIA-N PRESENT AT T+1
TRNSFM
306 AMT(I+1,L)=AMT(I,L)-R(I,1)R(I,2)-R(I,3)
TRNSFM
IF(AMT(I+1,L))622,623,623
TRNSFM
622 AMT(I+1,L)=0.0
TRNSFM
TRNSFM
ENTER NITRATE-N ROUTINE
TRNSFM
623 L=4
TRNSFM
621 L=3
C
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
Page 71
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TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
TRNSFM
NEXT
OF
TIME
STEP
AMOUNTS
FOR
START
C
COMPUTE
TRNSFM
DO 632 L =1,4
TRNSFM
AAMT(M +1,L) =AMT(K +1,L)
TRNSFM
TRNSFM
C
ENTER ROUTINE TO CHECK FOR CONVERGENCE OF PREDICTED OUTPUT
TRNSFM
IF(K.GT.1) GO TO 721
TRNSFM
GO TO 722
TRNSFM
A(L) = A(L) + 0.0001
721 IF(AAMT(M +1,L).EO.A(L))
TRNSFM
IF(ABS(AAMT(M +1,L)- A(L)).LE.CH) GO TO 632
TRNSFM
722 A(L) =AAMT(M +1,L)
TRNSFM
632 CONTINUE
TRNSFM
IF(A(1)- AAMT(M +1,1))633,634,633
TRNSFM
633 IF(A(2)- AAMT(M +1,2))635,634,635
TRNSFM
635 IF(A(3)- AAMT(M+1,3))636,634,636
TRNSFM
636 IF(A(4)- AAMT(M +1,4))641,634,641
TRNSFM
X =2. *X
634
TRNSFM
K =2*K
TRNSFM
TRNSFM
C
CHECK FOR MAXIMUM NUMBER OF ITERATIONS ALLOWED
TRNSFM
IF(K.GT.128) GO TO 300
TRNSFM
GO TO 612
TRNSFM
300
CONTINUE
TRNSFM
641
AOR(J1) =0.0
TRNSFM
TRNSFM
C
CONVERT UNITS TO UG /SEGMENT
TRNSFM
00 6001 J =1,4
TRNSFM
AAMT(1,J) = AAMT(i,J) *CONVERT
TRNSFM
6001 AAMT(2,J) = AAMT(2,J)''CONVERT
TRNSFM
MMMM = MMMM + 1
ORN(Ji) = AAMT(1,2) =SAMT(1,2)* 0.4 /CNR(J1)*CONVERT TRNSFM
IF(MMMM.LT.Q
TRNSFM
CNR(J1) =0.0
TRNSFM
TRNSFM
COMPUTE DELTA VALUES FOR COMPONENTS
C
TRNSFM
DELN03 = AAMT(2,4) - AAMT(1,4)
TRNSFM
RATIO = AAMT(2,3) /AAMT(1,3)
TRNSFM
FIRST = AAMT(1,3) - ENH3
TRNSFM
FINAL = FIRST *RATIO
TRNSFM
FINALI = BNH4(J1)4RATIO
TRNSFM
D LNH3 = FINAL - FIRST
TRNSFM
DELORGN = AAMT(2,2) - AAMT(1,2)
TRNSFM
DELUREA = AAMT(2,1) - AAMT(1,1)
TRNSFM
DELBNH4 = FINAL/ - BNH4(J1)
TRNSFM
DELRN = AAMTRN(2) - RN(J1)
TRNSFM
DELRC-= AAMTRC(2) - RC(J1)
TRNSFM
IF(DELBNH4.LE.0.0) Sis = 0.0
TRNSFM
TRNSFM
C
RETURN TO SUBROUTINE COMBINE
TRNSFM
RETURN
TRNSFM
END
XCHANGE
,EXAMG,EXHCO3,EXC03,EXSO4,EXC
XCHANGE(J,EXNH3,
EXCA,
EXANA
SUBROUTINE
XCHANGE
1L,EXBNH4)
XCHANGE
XCHANGE
C
THIS IS THE EXCHANGE SUBROUTINE
XCHANGE
COMPUTE AMOUNT OF NITRATE -N PRESENT AT T +1
IF(R(I,5).GT.R(I,3))900,901
900
IF (CN(I).LE.10.0.AND.AMT(I,4).LE. 6 .0)AMT(I +1,2) =AMT(I +i,2)- (R(I,5
1)- R(I,3))
IF (CN(I).LE.10.D.AND.AMT(I,4).LE. 6.0) R(I,5) =R(I,3)
901
CONTINUE
AMT (I +1,L) =AMT(I,l) +R(I,3)- R(I,5)
IF(AMT(I +1,L))624,625,625
624 AMT(I+1,L) =0.0
625
CONTINUE
611 CONTINUE
G
)
Page 72
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255'
256
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287
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2
3
4
5
6
COMMON /XXX /DELX,DELT,MM,START,BO(25 ),TEN(25 ),CHECK(25 ),MOISIN
1(25 ),CMH202(25 ),MOISOUT(25 ),AN03(25 ),ANHZ(25 ),UREA(25 ),ORN
2(25 ),CZ(25 ),ANZ(25 ),AMZ(25 ),HCOZ(25 ),CY(25 ),COZ(25 ),SOZ(25
3),EZ(25 ),CX(25 ),SAZ(25 ),XXZ(25 ),CASZ(25 ),AGSZ(25 ),BNHZ(25 ),
4EY(25 ),CN1(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAZ(25 ),Q,CRO
1P, XTRACT, SUMNO3, THOR( 4),TO,IDAY,U3(25),CH,CH1,IRERUN
DIMENSION CMH201(25)
DATA (TES = 0.000001)
SET SEGMENT VOLUMES
C
CMH2O1(J) =CMH2O2(J)
MOISTURE CONTENT ON
B1 = CMH2O1(J) / (8O (J) *DELX)
B1 = 81 +100.
C--- COMPUTE
A
PERCENT BASIS
C
COMPUTE SEGMENT VOLUMES BASED ON INITIAL SOIL ANALYSES
IF(CHECK(J).EQ.0.0)CMH2O1(J) =XTRACT *DELX *BD(J)
C
CONVERT UNITS FROM UG /SEGMENT TO MOLES /LITER
C
RESET STORAGE LOCATIONS FOR USE IN THIS ROUTINE
ANH4 = ANHZ(J) /CMH2O1(J) /14000.
A = CZ(J) /CMH2O1(J) /40080.
S = ANZ(J) /CMH2O1(J)/22990.
F = AMZ(J) /CMH201(J)/24320.
HCO3 = HCOZ(J) /CMH201(J) /61000.
CO3 = COZ(J) /CMH2O1(J) /60000.
H = CY(J) /CMH2O1(J) /35460.
G = SOZ(J) /CMH2O1(J) /96100.
$XXT = XXZ(J)
$CT = CX(J)
$SAT = SAZ(J)
ET = EZ(J)
$BNH4 = BNHZ(J)
CASO = CASZ(J)
$AGSO = AGSZ(J)
$ CAL = CAZ(J)
EC = EY(J)
1005
IF(CHECK(J).EQ.0.0)200,201
CALL THE EQULIBRIUM EXCHANGE SUBROUTINE IF THIS IS THE FIRST
TIME INTERVAL
C
C
200
CALL EQEXCH( A, F, S, H,G,HCO3,CO3,EC,ANH4,ET,CT,SAT,
ICASO,AGSO,BNH4,U)
ET = ET /2.
CT = CT /2.
A
= A /2.
F /2.
XXT = XXT /2.E5
DA =0.707
F =
201
0 =0,67
DNH4 =0.22
8 =
81
IF(CHECK(J).EQ.0.0) B = XTRACT *100.
IF(CHECK(J).NE.0.0) U= SQRT( 2.0 *(A +F +G +CO3) +0.5 *(S +HCO3 +H))
IF (CAL) 1000,602,603
602 IK =1
AAA =452.
GO TO 604
603 IK =2
ZE =( A «HCO3 * *2 *EXP(- 2.341 *U /(1. +U)))
AAA =8
AAA =(AAA* *1.68) *ZE
604 ZE =AAA /(B1* *1.68)
299
IF(CHECK(J).EQ.0.0)299,298
CONTINUE
RATIO =B /Bi
SG =G *RATIO
A =A *RATIO
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE.
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE,
_
Page 73
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8
9
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24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
$H=H*RATIO
F=F*RATIO
3CAS0 = CASO*RATI-0
S=S*RATIO
3ANH4=ANH4*RATIO
AGSO=AGSO*RATIO
CO3 = CO3*RATIO
HCO3 = HCO3*RATIO
8 = 1.E5/8
298
24 A1=A
IF(XXT)4,4,26
4 U=SQRT (2. 0* (A+F+G)+0. 5* (S+H+HCO3) )
(-9.366*U/(1.0+U))
AA=EXP
IF(2.4E-5-A*G*AA)26,18,19
26 X=0.0
U=SQRT(2.0*(A+F+G)+0.5*(S+H+HCO3))
BB= A+G
EX=(9.366*U)1(1.0+U)
(EX)
CC=A*G-(2.4E-5)*EXP
R=SQRT(B8*BB-4.0*CC)
X=(-88+R) /2.0
CAS1=4.897E-3-CASO
DEL=8*XXT-CAS1
IF(DEL-X)27,28,28
X=XXT*8
27
XXT=0.0
CAS1=0.0
A=A+X
G=G+X
U=SQRT(2.0*(A+F+G)+0.5*(S+H+HCO3))
AA=EXP (-9.366*U/(1.+U))
7 B8=-(4.9E-3+AA*A+AA*G)
CC=A4*A*G-4.9E-3*CASO
XXXX=BB*98-4.0*AA*CC
IF(XXXX) 35,35,36
35 X1=0.0
GO TO 37
36 X1=(-R8-S(IRT(XXXX))/(2.0*AA)
37 CASO=CASO+X1
A=A-X1
G=G-X1
GO TO 44
IF (G) 1,1,6
6 IF (A) 1,1,7
44,44,7
i IF (CASO)
28 A=A+X
18
G=G+X
XXT=XXT-X/B
CASO=CASO+CAS1
XXT=XXT-CAS11B
44 A2=A
80,181,80
IF (S)
181 IF(SAT)80,515,80
80 IJ=2
404 IF(SAT-ET)402f403,403
402 Z=SAT/10.
Z1=Z
GO TO 5
403 Z=ET/10.
Z1=2
=X=EXP
((-2.341*U)/(1.0+U))
AA=-4.0*0A*DA*3*8
B8=4.0*R*(EX+2.0*DA*DA*ET*B+DA*DA*S)
CC=4.0*EX*(A+SAT*8)-4.0*OA*011*8*ET*(B*ET+2.0*S)-0A*0A*S*S
0O=SAT*EX*(4.0*A+SAT*B)+2.0*DA*DA*ET*S*(2.0*3*ET+S)
EE=SAT*SAT*A*EX-DA*DA*S*S*ET*ET
81 ZZ=-((((AA*Z+88)*Z+CC)*Z+DD)*Z+EE)
ZZZ=(((4.0*AA*Z+3.0*8B)*Z+2.0*CC)*Z+DD)
IF(ABS(ZZ).LT.TES.OR.ABS(ZZZ).LT.TES) GO TO 515
5
Page 74
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
73
74
75
76
77
XCHANGE
78
79
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
xCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
80
8i
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
XCHANGE,
133
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
134
135
136
137
138
83
552
551
550
510
zz=zz/zzz
IF(ABS(ZZ).LT.TES.OR.ABS(Z)
zzz=zz/z
2=Z+ZZ
IF(ABS(ZZZ)-.001)83,83,81
A=A+B*Z
IF(A)510,510,512
SAT=SAT-2.*Z
ET=ET+Z
S=S+2.*B*2
A=A-8*Z
.LT.TES)
GO TO 515
Z=-Z1
GO TO 81
512 S=S-2.*B*2
IF
550,550,513
(S)
513 ET=ET-Z
IF
(ET)551,551,514
514 SAT=SAT+2.0*Z
IF
552,552,515
(SAT)
515 A3=A
BB=A+B*(CT+D*ET)+O*F
AA=B*(1.0-D)
CC=(A*CT-0*F*ET)
R=SQRT (BB+BB-4.0*AA*CC)
Y=(-BB+R)/(2.0+AA)
A=A+B*Y
F=F-B*Y
ET=ET-Y
CT=CT+Y
A4=A
AA = 8*(1.0-ONH4)
BB = ANH4 + 43*(SAT+ONH4*BNH4)
CC = ANH4*SAT - DNH4*S*8NH4
+
ONH4*S
R=SQRT(BB*BB-4.0*AA*CC)
Y=(-BB+R)/(2.0*AA)
BNH4 = BNH4 - Y
SAT = SAT +
ANH4 = ANH4
S
= S
-
Y
+
B*Y
BY
IF(G)790,790,791
791 IF(F)790,790,792
792 AA=EXP(-9.366*U/(1.+U))
B8=-(5.9E-3+AA*F+AA*G)
CC=AA*F*G-5.9E-3*AGSO
XXXX=BB*BB-4.0*AA+CC
IF(XXXX)793,793,794
793 X1=0.0
GO TO 795
794 X1=(-BB-S(IRT(XXXX))/(2.0*AA)
795 AGSO=AGSO+X1
F=F-X1
G=G-X1
790 CONTINUE
GO TO (600,601),IK
601 AA=4.0
B8=4.*HCO3+A
CC=HCO3**2+4.*A*HCO3
OO=A*HCO3**2-ZE*EXP (2.341*U/(1.+U))
IF(HCO3-A)61,61,62
61 Z=-HCO3/4,
GO TO 650
62 Z=-A/2.
650 Z1=Z
63 ZZ=-(((AA*Z+BB)*Z+CC)*Z+OD)
ZZZ=((3.0*AA*Z+2.0*BB)*Z+CC)
IF(ABS(ZZ).LT.TES.OR.ABS(ZZZ).LT.TES) GO TO 600
Page 75
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
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XCHANGE
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XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
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XCHANGE
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ZZ=ZZIZZZ
IF(ABS(ZZ).LT.TES.OR.ABS(Z)
ZZZ=ZZ/Z
Z=Z+ZZ
IF(ABS(ZZZ)-.001)64,64,63
64 A=A+Z
HCO3=HCO3+2.*Z
IF(HCO3)752,752,651
752 HCO3=HCO3-2.*Z
A=A-Z
Z=-Z1
.LT.TES) GO TO 600
GO TO 63
651 IF(A) 752,752,753
753 CAL=CAL-Z
600
ZX=(A*HCO3**2*EXP(-2.341*U/(1.+U)))
IF(ZX-ZE)606,605,605
605 IK=2
606 DEL=A-A1
IF(DEL+CH1)24,48,48
48 IF(DEL-CH1)49,49,24
49 DEL=A-A2
IF(DEL+CH1)24,50,50
IF(DEL-CH1)51,51,24
51 DEL=A-A3
IF(DEL+CH1)24,52,52
52 IF(DEL-CH1)8,8,24
8 DEL=A-A4
IF(DEL+CH1)24,66,66
66 IF(DEL-CH1)67,67,24
1000
CONTINUE
67
CONTINUE
IF(CHECK(J).EQ.0.0) CMH2O1(J) = CMH202(J)
ANH4 = ANH4*CMH2O1(J)*14000.
A = A*CMH2O1(J)*40080.
S = S*CMH2O1(J)*22990.
F = F*CMH2O1(J)*24320.
HCO3 = HCO3*CMH2O1(J)*61000.
H = H*CMH2O1(J)*35460.
CO3 = CO3*CMH2O1(J)*60000.
G = G*CMH2O1(J)*96100.
IF(CHECK(J).LQ.0.0)400,401
ANHZ(J) = ANH4
400
$CZ(J) = A
ANZ(J) = S
gAMZ(J) = F
HCOZ(J) = HCO3
$COZ(J) = CO3
CY(J) = H
$SOZ(J) = G
BNHZ(J) = BNH4
CHECK(J)=CHECK(J)+1.
401
CONTINUE
50
C
C
COMPUTE DELTA VALUES FOR COMPONENTS
EXNH3 = ANH4 - ANHZ(J)
$EXCA = A - CZ(J)
EXANA = S - ANZ(J)
$EXAMG = F - AMZ(J)
S6EXC03 = CO3 - COZ(J)
EXHCO3 = HCO3 - HCOZ(J)
EXCL = H - CYO)
$EXSO4 = G - SOZ(J)
EXBNH4 = 9NH4 - BNHZ(J)
EZ(J) = ET
$CX(J) = CT
SAZ(J)=SAT
$XXZ(J)=XXT
$AGSZ(J)=AGSO
CASZ(J)=CASO
CAZ(J)=CAL
$EY(J)=EC
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
XCHANGE
RETURN TO SUBROUTINE COMBINE
XCHANGE
RETURN
XCHANGE
ENO
XCHANGE
SUBROUTINE EQEXCH(CA,AMG,SOS,CL,SO,HCO3,CO3,£C,ANH4iE5iC5,SA5,CAS0 EQEXCH
1,AGSO,BNH4,U)
EOEXCH
EQEXCH
Page 76
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2
3
4
THIS SUBROUTINE COMPUTES THE AMOUNTS OF IONS CONTAINED ON THE EXCHANGE COMPLEX (BASED ON INITIAL SOIL ANALYSIS)
C
C
DA=2.00
0=0.67
ONH4=0.22
CASO=0.0
U=SQRT(2.0*(CA+AMG+SO+CO3)+0.5*(SOS+HCO3+CL))
AGS0=0.0
42 ACT2=EXP(-9.366*U/(1.0+U))
IF (SO) 1000,713,712
712 AA=ACT2*ACT2
BB=ACT2* (10.8E-3+ (ACT 2* (AMG+CA-S0) ) )
CC=28.91E-6+(ACT2*(AMG*4.9E-3+(CA*5.9E-3)(SO*10.8E-3)))
OD=-S0*28.91E-6
800 Z=SO/2,
850 Z1=Z
863 ZZ=(((AA*Z+BB)*Z+CC)*Z+OD)
ZZZ=((3.0*AA*Z+2.0*BB)*Z+CC)
ZZ=ZZ/ZZZ
ZZZ=ZZIZ
Z=Z+ZZ
IF
(ABS(ZZZ).001)840,840,863
SOT=SO
SO=Z
IF(SO)710,710,711
710 SO=SOT
Z=Zi
GO TO 863
711 CASX=SO*CA*ACT2/(4.9E-3+ACT2*S0)
CX=CA-CASX
840
AGSX=SO*AMG*.ACT2/(5.9E3+ACT2*SO)
AMX=AMG-AGSX
UU-SQRT(2.*(CX+AMX+SO+CO3)+0.5*(SOS+HCO3+CL))
IF(ABS(UU/U1.)-1.0E-4) 40,40,41
41 U=UU
SO=SOT
GO TO 42
40 CASO=CASX
AGSO=AGSX
CA=CX
AMG=AMX
713 ACT1=SQRT(ACT2)
ACTM=SQRT(ACT1)
ACTM=SQRT(ACTM)
CA=CA*2.
AMG=AMG*2.
1000
E5=EC/((ACTM*SOS/(DA*SQRT(ACT1*CA)))+1.+(0*ACT1*AMG/(ACT1*CA)))
SA5=ACTM*SOS*E5/(SQRT(ACTi*CA)*DA)
C5=EC-E5-SA5
BNH4 = (SA5*ANH4)/(SOS*ONH4)
RETURN
END
C
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EOEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
EQEXCH
E QEXCH
EQEXCH
SUBROUTINE FL(J,FLNO3,FLNH3,FLUREA,FLCA,FLANA,FLAMG,FLHCO3,FLCL,FI FL
FL
1CO3,FLSO4)
FL
FL
THIS IS THE SOLUBLE COMPONENT LEACHING SUBROUTINE
FL
FL
COMMON/XXX/DELX,DELT,MM,START,BD(25 ),TEN(25 ),CHECK(25 ),MOISIN
FL
1(25),ORMOIS(25),MOISOUT(25),BN03(25),BNH3(25),BREA(25),ORN
FL
2(25),BA(25),BNA(25),BMG(25),BC03(25),BL(25),903(25),BO4(25
3),E5(25 ),C5(25 ),SA5(25 ),XX5(25 ),CASO(25 ),AGSO(25 ),BNH4(25 ), FL
4EC(25 ),CN1(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAL(25 ),Q,CRO FL
iP,XTRACT,SUMNO3,THOR(4),TO,IDAY,US(25),CH,CHI,IRERUN,IShiCH,CUMSUM, FL
FL
iSUMOUT
FL
COMiMON/GIRL/UREAltUREAZONti31AQNH3LON011_,iZN032kCA1._,ANA1ALAMQii
Page 77
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T
8
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13
1.4
1HC031,CL1,C031,SO41,K
DIMENSION ANH3(25),AN03(25),UREA(25),CA(25),ANA(25),AMG(25),HCO3(2
15),CL(25),CO3(25),SO4(25)
INTEGER Q
REAL MOISIN,MOISOUT
IF(J.NE.2) GO TO
00 18 I=1,Q
1
18
ANH3(I)=8NH3(I)
?AN03(I)=BN03(I) bUREA(I)=BREA(I) 3CA(I)=8A(I)
ANA(I)=BNA(I) $AMG(I)=BhIG(I) $HCO3(I)=9CO3(I) $CL(I)=8L(I)
CO3(I)=803(I) $SO4(I)=B04(I)
CONTINUE
C
SET Q+1 VALUES EQUAL TO Q VALUES
1
ORMOIS(Q+1) = ORMOIS(Q)
ANH3(Q+1) = ANH3(Q)
$AN03(Q+1) = ANO3(Q)
$CA(Q+1) = CA(Q)
UREA(Q+1) = UREA(Q)
ANA(Q+1) = ANA(Q)
ñAMG(Q+1) = AMG(Q)
$CL(Q+1) = CL(Q)
HCO3(Q+1) = HCO3(Q)
$SO4(Q+i) = SO4(Q)
CO3(Q+1) = CO3(Q)
CONTINUE
COMPUTE COEFIN ANO COEFOUT
IF(MOISIN(J).LT.0.0)2,3
COEFIN = MOISIN(J)/ORMOIS(J)
C
2
GO TO 4
IF(ORMOIS(J-1).GT.0.0) GO TO 14
COEFIN=0.0
GO TO 15
14 COEFIN=MOISIN(J)/ORMOIS(J-1)
15 CONTINUE
IF(MOISOUT(J).LT.0.0)5,6
COEFOUT = MOISOUT(J)/ORMOIS(J+1)
3
4
5
GO TO
6
7
8
7
COEFOUT = MOISOUT(J)/ORMOIS(J)
IF(COEFIN.LT.0.0) 8:9
K=J
GO TO 10
9
10
li
K=J-1
IF(COEFOUT.LT.0.0)11,12
L=J+1
GO
TO 13
12
L=J
C
COMPUTE DELTA VALUES FOR AMOUNTS
CONTINUE
IF(ABS(COEFIN).GT.1.0) COEFIN = A8S(COEFIN)/COFFIN
IF(ABS(COEFOUT).GT.1.0) COEFOUT = ABS(COEFOUT)/COEFOUT
$0NO32=COEFOUT*AN03(L)
ON031=COEFIN*AN03(K)
$ONH32=COEFOUT*ANH3(L)
ONH31=COEFIN*ANH3(K)
$UREA2=COEFOUT*UREA(L)
UREA1=COEFIN*UREA(K)
CA1=COEFIN*CAEK)
$CA2=COEFOUT*CA(L)
$ANA2=COEFOUT*ANA(L)
ANA1=COEFIN*ANA(K)
AMG1=COEFIN*AMG(K)
$AMG2=COEFOUT*AMG(L)
HC031=COEFIN*HCO3(K)
SHC032=COEFOUT*HCO3(L)
CLI=COEFIN*CL(K)
$CL2=COEFOUT*CL(L)
CO31=C0EFIN*CO3(K)
$C032=COEFOUT*CO3(L)
SO41=COEFIN*SO4(K)
$SO42=COEFOUT*SO4(L)
FLNO3 = 0N031 - ON032
FLNH3 = ONH31 - 0NH32
FLUREA = UREA1 - UREA2
FLCA = CA1 - CA2
FLAMA = ANA1 - ANA2
FLAMG = AMG1 - AMG2
13
Page 78
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
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FLHCO3 = HC031 - HC032
FLCL = CL1 - CL2
FLCO3 = CO3i - C032
FLSO4 = S041
SO42
FL
FL
FL
FL
FL
FL
FL
FL
RETURN TO SUBROUTINE COMBINE
RETURN
C
END
UPTAKE
UPTAKE
PLANT NITROGEN UPTAKE SUBROUTINE
UPTAKE
UPTAKE
UPTAKE
COMMON /XXY /ICHECK,ICOUNT,CONV, K, K1,CROP,FACT
UPTAKE
COMMON /XXX/ ELX, ELT,MS,WTART,BO(25 ),TEN(25 ),CHECK(25 ),MOISIN
UPTAKE
1(25 ),CMH2O1(25 ),MOISOUT(25 ),AN03(25 ),ANH3(25 ),UREA(25 ),ORN
2(25 ),CA(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),SO4(25 UPTAKE
3),E5(25 ),C5(25 ),SA5(25 ),XX5(25 ),CASO(25 ),AGSO(25 ),BNH4(25 ), UPTAKE
4EC(25 ),CN1(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAL(25 ),Q,SRO UPTAKE
1P, XTRACT,SUMN03,THOR(4),TO,IOAY,V ( 25),CH,CH1,IRERUN,ISWCH,CUMSUM, UPTAKE
UPTAKE
iSUMOUT,REDUCE
UPTAKE
REAL KP2,K,K1
UPTAKE
INTEGER CROP
UPTAKE
DIMENSION KP2(6,3),UPTK(24)
UPTAKE
IF(CROP.EQ.1) GO TO 15
IF(ICHECK.EQ.0)1,2
UPTAKE
UPTAKE
ICHECK = ICHECK + 1
UPTAKE
UPTAKE
READ ROOT DISTRIBUTION
UPTAKE
READ 4,(KP2(J,3),J =1,6)
UPTAKE
READ PLANT UPTAKE OF N DATA FROM CAROS
UPTAKE
UPTAKE
READ 3, (UPTK(J),J =1,24)
UPTAKE
PRINT ROOT DISTRIBUTION
UPTAKE
PRINT 11, (KP2(J,3),J =1,6)
UPTAKE
UPTAKE
DO 6 J =1,24
UPTAKE
UPTK(J) = UPTK(J) *CONV
UPTAKE
PRINT PLANT UPTAKE OF N DATA
UPTAKE
UPTAKE
PRINT 12, (J,UPTK(J),J =1,24)
PRINT 10
UPTAKE
UPTAKE
CONTINUE
UPTAKE
IF(I.EQ.2) ICOUNT = ICOUNT + 1
UPTAKE
D = DELX *(I 1.)
DEL = OELX /30.5
UPTAKE
UPTAKE
U = UPTK(ICOUNT)
UPTAKE
UPTAKE
ADJUST UPTAKE VALUES FOR LENGTH OF TIME INTERVAL
U= U /15.*OELT
UPTAKE
UPTAKE
FOR SIZE OF DEPTH SEGMENT ANO ROOT DISTRIB UPTAKE
ADJUST UPTAKE VALUES
UPTAKE
UTION
UPTAKE
IF(D.LE.30.5) U = U *KP2(1,CROP) *DEL
U= U *KP2(2,CROP) *DEL
UPTAKE
IF(D.GT.30.5.AND.D.LE.61.0)
U= U *KP2(3,CROP) *DEL
UPTAKE
IF(D.GT.61.0.AND.D.LE.91.5)
U= U*KP2(4,CROP) *DEL
UPTAKE
IF(D.GT.91.5.AND.O.LE.122.)
U= U *KP2(5,CROP) *DEL
IF(D.GT.122..AND.D.LE.153.)
UPTAKE
UPTAKE
U =U *KP2(6,CROP) *DEL
IF(D.GT.153..ANO.O.LE.183.)
UPTAKE
IF(D.GT.183.AND.D.LE.214.)8,9
UPTAKE
IF(CROP.EQ.2) U = U *0.08 *OEL
UPTAKE
IF(CROP.EQ.1) U = 0.0
UPTAKE
IF(D.GT.214.) U = 0.0
UPTAKE
UPTAKE
DISTRIBUTE THE N UPTAKE BETWEEN NO3 AND NH4
$PLNH4 = -U *K1
PLNO3 = -U *K
UPTAKE
GO TO 16
UPTAKE
SUBROUTINE UPTAKE(I,PLN03,PLNH4,OELT,DELX)
C
C
C
i
C
C
C
6
C
2
C
7
C
C
8
9
C
Page 79
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UPTAKE
UPTAKE
16
UPTAKE
UPTAKE
UPTAKE
UPTAKE
FORMAT(10X,F10.0)
3
UPTAKE
FORMAT(6F10.0)
4
UPTAKE
FORMAT(1H1)
10
FORMAT( / /10X *PLANT NITROGEN UPTAKE DATA INPUT FROM CARDS* / /10X*R00 UPTAKE
11
61.0 CM *3X *61.0 - 91.5 UPTAKE
35.5 CM *3X *35.5
17. DISTRIBUTION * /10X' 0
UPTAKE
-*//1)(,6F16.2)
*153
CM
*3X
CM
153
*3X
*122
CM
122
2CM *3X'91.5 FORMAT( / /10X *TOTAL PLANT UPTAKE OF NITROGEN(UG /15 DAYS)' / /(10X,I3, UPTAKE
12
UPTAKE
1F10.2))
UPTAKE
ENO
MCHECK
SUBROUTINE MCHECK
MCHECK
MCHECK
WITH
NITROGEN
OF
STATUS
MASS
BALANCE
THE
COMPUTES
THIS SUBROUTINE
C
MCHECK
RESPECT TO THE SYSTEM
C
MCHECK
MCHECK
COMMON /EEE /PSUM,DIFNH4,DIFNO3,TPLANT
MCHECK
COMMON /XXX /DELX,DELT,MS,WTART,BD(25 ),TEN(25 ),CHECK(25 ),MOISIN
MCHECK
),ORN
),UREA(25
),ANH3(25
),AN03(25
1(25 ),CMH2O1(25 ),MOISOUT(25
MCHECK
2(25 ),CA(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),SO4(25
3),E5(25 ),C5(25 ),SA5(25 ),XX5(25 ),CASO(25 ),AGSO(25 ),BNH4(25 ), MCHECK
4EC(25 ),CN1(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAL(25 ),Q,SRO MCHECK
1P, XTRACT,SUMNO3,THOR(4),TO,IDAY,U ( 25),CH,CHI,IRERUN,ISWCH,CUMSUM, MCHECK
MCHECK
1SUMOUT
MCHECK
MCHECK
INTEGER Q
MCHECK
MCHECK
S1 = 0.0
MCHECK
FA = DELX *14.E6
MCHECK
MCHECK
IN
SYSTEM
MASS
NITROGEN
OF
COMPUTE CURRENT
C
MCHECK
00 1 J =1,Q
+
MCHECK
ANO3(J)
+
+
ORN(J)
*FA
UREA(J)
S1 = S1 + ANH3(J) + BNH4(J)48O(J)
1
MCHECK
MCHECK
C----- COMPUTE INITIAL MASS OF NITROGEN IN SYSTEM
MCHECK
-CUMSUM
+
PSUM
SUMOUT IF(S2.EQ.0) S2 = S1
MCHECK
MCHECK
COMPUTE CHANGE IN STORAGE FOR NITROGEN
C
MCHECK
S3 = S1 - S2
MCHECK
PSUM1 = ABS(TPLANT)
MCHECK
MCHECK
FOR
NITROGEN
COMPUTE TOTAL INPUT - TOTAL OUTPUT
C
MCHECK
+PSUM -DIFNH4 -DIFNO3
SUMOUT
OUTIN = CUMSUM
MCHECK
ISWCH = 0
MCHECK
PRINT 99
MCHECK
MCHECK
PRINT VALUES COMPUTED ABOVE
C
MCHECK
OIFNO3)
PPP = ABS(PSUM - DIFNH4 MCHECK
PRINT 100, S2,CUMSUM,SUMOUT,PPP ,OUTIN,S3,PSUM1
MCHECK
PRINT 98
MCHECK
RETURN
MCHECK
MCHECK
MCHECK
FORMAT(1H1 / / //)
98
MCHECK
//)
FORMAT(
/
99
FORMAT(5X *SUMMARY OF NITROGEN BALANCE FOR SYSTEM' /10X *INITIAL NITR MCHECK
100
ADDED TO SYSTEM = *,E21.6, MCHECK
10GEN CONTENT = *,E20.6,2X *UG * /10X *TOTAL
MCHECK
22X *UG * /10X *TOTAL -N LEACHED FROM SYSTEM = *,E17.6,2X *UG * /i0X *TOTAL
F
MCHECK
OUTPUT
TOTAL
INPUT
*
/10X
*TOTAL
3 UPTAKE BY PLANTS =4-,E20.6,2X*UG
40R N -*,E20.6,2X *UG* /10X *CHANGE IN N STORAGE SINCE START OF RUN =' MCHECK
5,E14.6,2X*UG * / /10X *TOTAL -N UPTAKE BY PLANTS(ATTEMPTED) = *,E20.6,2X MCHECK
MCHECK
6 *UG*)
MCHECK
END
15
PLNO3 = -V(I) *K +FACT
CONTINUE
RETURN
$PLNH4
=
-V(I) *K1 *FACT
N
Page 80
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SUBROUTINE TEMP
C
C
C
C
C
1
C
23
C
C
21
C
20
C
C
TEMP
TEMP
THIS SUBROUTINE READS IN TEMPERATURES FOR THE TEMPERATURE HORIZONS TEMP
AND STORES THEM IN THE PROPER ARRAY LOCATIONS
TEMP
TEMP
TEMP
COMMON /XXX /DELX,DELT,MS,WTART,B0(25 ),TEN(25 ),CHECK(25 ),MOISIN
TEMP
1(25 ),CMH2O1(25 ),MOISOUT(25 ),AN03(25 ),ANH3(25 ),UREA(25 ),ORN
TEMP
2(25 ),CA(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),504(25
TEMP
3),E5(25 ),C5(25 ),SA5(25 ),XX5(25 ),CASO(25 ),AGSO(25 ),9NH4(25 ), TEMP
4EC(25 ),CNI(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAL(25 ),Q,CRO TEMP
IP,XTRACT,SUMN03,THOR(4),TO
TEMP
TEMP
INTEGER Q,TO,CROP
TEMP
TEMP
DIMENSION TTEM(4)
TEMP
TEMP
TEMP
TEMP
TEMP
READ TEMPERATURES IN DEGREES C
READ (8) (TTEM(J),J =1,TO)
TEMP
TEMP
TEMP
TEMP
COMPUTE BOTTOM OF TEMPERATURE HORIZON
TEMP
KK = THOR(L) /DELX + 1.1
TEMP
DO 23 J =N,KK
TEMP
TEMP
STORE TEMPERATURES
TEMP
TEM(J) = TTEM(L)
TEMP
TEMP
CHECK FOR LAST HORIZON
TEMP
IF(KK.EQ.(1)20,21
TEMP
TEMP
RESET COUNTERS
TEMP
N =KK + 1
$L = L + 1
TEMP
GO TO 1
TEMP
TEMP
RETURN TO MAIN PROGRAM
TEMP
RETURN
TEMP
ENO
TEMP
SUBROUTINE PRNT(IPRINTI,IPRINTJ)
PRNT
PRNT
THIS SUBROUTINE PRINTS CONTROL AND INPUT DATA
PRNT
PRNT
COMMON/ ABLE / TITLE( 10), SMONTH, MM, O, IPRINT,JPRINT,INK,IPUNCH,ISTOP, PRNT
IITEST, IREADP, IMASS, IADO (25),IORNAP(5),HOR(9),TOTN(99), YEAR
PRNT
,
2AIRR( 9), IRR( 25), TT( 60), FERT( 7), OFERT (3),NORGIN,NFERTIN,NTEMPIN,
PRNT
3ITOT,JTOT,IRTOT,NT
PRNT
COMMON /XX2 /Ai,A2,A3,X
PRNT
COMMON /YYY /START,IDTE,MONTH,I,LL
PRNT
COMMON/ XXY /ICHECK,ICOUNT,CONV,PK,PK1,CROP
PRNT
COMMON /XXX /DELX,DELT,MS,WTART,BD(25 ),TEN(25 ),CHECK(25 ),MOISIN
PRNT
1(25 ),CMH2O1(25 ),MOISOUT(25 ),AN03(25 ),ANH3(25 ),UREA(25 ),ORN
PRNT
2(25 ),CA(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),SO4(25 PRNT
3),E5(25 ),C5(25 ),SA5(25 ),XXS(25 ),CASO(25 ),AGSO(25 ),BNH4(25 ), PRNT
4EC(25 ),CN1(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAL(25 ),Q,SRO PRNT
1P, XTRACT,SUMNO3,THOR(4),TO,IDAY,U ( 25),CH,CHI,IRERUN,ISWCH,CUMSUM, PRNT
ISUMOUT,REDUCE
PRNT
PRNT
INTEGER TITLE,SMONTH,START,O,TO,YEAR
PRNT
PRNT
PRNT
PRINT TITLE
PRNT
PRINT 100,TITLE
PRNT
IF(IPRINTI.EQ.2)._GO TO 1
PRNT
SET COUNTERS
L =1
$N =2
Page 81
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C
C
1
C
C
C
10
PRINT BASIC CONTROL CARD PARAMETERS
PRINT 101, SMONTH,XTRACT, START, CROP,LL,PK,HM,PKisDELX,CH,DELT,
1CH1 ,O,A1,TO,A2,ISTOP,YEAR,REDUCE
PRINT I -O CONTROL PARAMETERS
PRINT 102, IPRINT, IREAOP ,JPRINT,ITEST,INK,IMASS,IRERUN ,IPRINTI,
IIPUNCH,IPRINTJ
RETURN
ENTRY PRIT1
SKIP PAGE
PRINT 103
PRNT
PRINT TEMPERATURE HORIZONS
PRINT 104, (THOR(J),J =1,TO)
PRINT 109
REWIND 8
PRNT
PRNT
PRINT TEMPERATURES
DO 10 J =1,NT
READ (8) (TT(I),I =1,TO)
PRINT 105, J, (TT(I),I =1,TO)
REWIND 8
C
SKIP PAGE
PRINT 103
C
PRINT WATER ANALYSIS HEADING
PRINT 107
C
PRINT IRRIGATION WATER ANALYSIS
PRINT 108, (AIRR(I),I =1,9)
C
PRINT IRRIGATION APPLICATION DATES
PRINT 110, (ItR(I),I =1,IRTOT)
C
PRINT FERTILIZER APPLICATION DATES
PRINT 111, (IADD(I),I =1,ITOT)
PRINT 112
REWIND 9
DO 2 I =1,ITOT
READ (9) (FERT(J), J =1,7)
FNH4 = FERT(2) *CONY *0.7777 $FNO3= FERT(3)*CONV *.2258
FUREA = FERT(4)*CONV.4466 $FCA = FERT(5) *CONY
$FCO3 = FERT(7) *CONV
FSO4 = FERT(6) *CONV
C
PRINT FERTILIZER APPLICATIONS
PRINT 113, I, FERT( 1 ),FNH4,FNO3,FUREA,FCA,FSO4,FC03
REWIND 9
REWIND 10
PRINT 109
2
C
PRINT ORGANIC APPLICATION DATES
PRINT 114, (IORNAP(J),J= 1,JTOT)
PRINT 115
DO 3 I= 1,JTOT
READ (10) (OFERT(J),J =1,3)
FORN = OFERT (3) *CONV* 0. 4 /OFERT (2)
3
PRINT ORGANIC APPLICATIONS
PRINT 113, I,OFERT(1),OFERT(2),FORN
REWIND 10
C
PRINT COMPONENT HORIZON DEPTHS
C
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
Page 82
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
27
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76
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79
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89
90
91
92
PRINT 106,
PRINT 103
RETURN
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
(HOR(J),J =1,0)
FORMAT(1H1 //,38X,10A8//)
FORMAT(56X *CONTROL CARD SUMMARY * /57X *(BASIC PARAMETERS) * //35X
= *,F5.1,/35X
= *,I5,10X *XTRACT
1 *STARTING MONTH
= *,I5/35X
= *,I5,10X *CROP
i *STARTING DAY
2 *RELATIVE STARTING DAY = *,I5,10X *UPTAKE(NO3) = *,F5.2,/35X
= *,F5.2,/35X
3 *RELATIVE TERMIN DAY
= *,I5,10X *UPTAKE(NH4)
= *,F5.2,/35X
= *,F5.1,* CM *7X, *CONVERG1
4 *SOIL SEGMENT SIZE
= *,F5.3/35X
= *,F5.2,* DAYS *5X *CONVERG2
5 *TIME INTERVAL SIZE
= *,F5.1/35X
6 *NO. OF COMPONENT HRZNS =*,I5,10X *CHECK1
= *,F5.1/35X
7 *NO. OF TEMP HRZNS
= *,I5,10X *CHECK2
*,I5,10X *YEAR
= *,I5/35X
8 *ISTOP
9 *REDUCE
= *,F5.0 / / //)
FORMAT(55X *(I
CONTROL PARAMETERS) * //35X
*,I5/35X
= *,I5,10X *IREADP
1 *IPRINT
= *,I5/35X
2 *JPRINT
= *,I5,10X *ITEST
= *,I5/35X
3 *INK
= *,I5,10X *IMASS
*,I5/35X
4 *IRERUN
= *,I5,10X *IPRINTI
5 *IPUNCH
= *,I5,10X *IPRINTJ
= *,I5 / / //)
FORMAT(1H1)
FORMAT( //15X *WEEKLY TEMPERATURE DATA *13X *HORIZON DEPTH(CM)*
1/46X,6(3X,F6.1))
FORMAT (20X,I3,2X *TEMPERATURE(DEG C) = *2X,6F9.1)
FORMAT( / /10X *COMPONENT HORIZON OEPTHS(CM)* , 6X,6(3XF6.1))
FORMAT(10X *IRRIGATION WATER ANALYSIS (PPM) * /10X *NH4 *7X *NO3 *7X *CA *7
iX *NA *7X *MG *6X *HCO3 *7X *CL *7X *CO3 *7X *SO4 *)
FORHAT(3X,9F10.2 //)
0
FORMAT( //)
FORMAT(10X *IRRIGATION APPLICATION OATES * /8X,20I5)
FORMAT( / /10X *FERTILIZER APPLICATION DATES * /8X,20I5)
FORMAT( / /10X *FERTILIZER APPLICATIONS (UG) * /10X *DEPTH *5X *NH4 *5X *NO3*
15X *UREA *5X *CA *5X *SO4 *5X *CO3 *)
FORMAT(2X,I5,7F8.1)
FORMAT(10X *ORGANIC
APPLICATION DATES * /8X,5I5)
APPLICATIONS(UG) */10X *DEPTH *5X *G /N *5X *ORN *)
FORMAT( / /10X *ORGANIC
N
N
ENO
SUBROUTINE CHK(L1,L2,L3,J, EXNH3, EXCA ,EXANA,EXAMG,DELN03,DELNH3,0EL
1ORGN,DELUREA)
C
C
C
THIS SUBROUTINE DETERMINES IF THE NITROGEN TRANSFORMATION AND/OR
ION EXCHANGE SUBROUTINES NEED BE CALLED FOR THIS TIME STEP (BASED
ON CRITERIA READ FROM DATA CARDS)
COMMON /XXX /OELX,DELT,MS,WTART,BD(25 ),TEN(25 ),CHECK(25 ),MOISIN
1(25 ),CMH201(25 ),MOISOUT(25 ),AN03(25 ),ANH3(25 ),UREA(25 ),ORN
2(25 ),CA(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),SO4(25
3),E5(25 ),C5(25 ),SA5(25 ),XXS(25 ),GASO(25 ),AGSO(25 ),BNH4(25 ),
4EC(25 ),CN1(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAL(25 ),Q,SRO
1P, XTRACT,SUMNO3,THOR(4),TO,IDAY,U (25),CH,CHI,IRERUN
COMMON /XX2 /A1,A2,A3,X
REAL MOISIN, MOISOUT
DIMENSION X(7,25)
L1 = L2
=
L3 =
0
6
IF(ABS( EXNH3 ).LT.A1.AND.ABS(EXCA).LT.A1)1,2
IF( ABS( EXANA) .LT.A1.AND.ABS(EXAMG).LT.A1)3,2
ANH3(J)).LT.Ai)4,2
IF(ABS(X(2,J)
CA(J)),LT.A1)5,2
IF(ABS(X(5,J)
ANA(J)).LT.A1)6,2
IF(A8S(X(6,J)
AMG(J)).LT.A1)7,2
IF(ABS(X(7,J)
7
L1 = 1
1
3
4
5
Page 83
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
PRNT
CHK
GHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
8
IF( ABS( OELN03). LTA2.AND.ABS(DELNH3).LT.A2)8,9
IF( ABS( DELORGN). LT .A2.AND.ABS(DELUREA).LT.A2)10,9
10
11
12
13
IF(ABS(X(1,J) - ANO3(J)).LT.A2)11,9
IF(ABS(X(2,J) - ANH3(J)).LT.A2)12,9
IF(ABS(X(4,J) - ORN(J)).LT.A2)13,9
IF(ABS(X(3,J) -UREA(J)).LT.A2)14,9
14
L2 = 1
IF( ABS( MOISIN( J)). GT. A3 .0R.ABS(MOISOUT(J)).GT.A3)15,16
L3 = 1
X(1,J) = AN03(J)
$X(2,J) = ANH3(J)
2
9
16
15
X(3,J)
X(51J)
X(7,J)
RETURN
END
=
=
=
UREA(J)
$X(4,J) = ORN(J)
$X(6,J) = ANA(J)
CA(J)
AMG(J)
INTEGER FUNCTION DAY(K,M)
L =
0
(1,2,3,4,5,6,7,8,9,10,11,12,13) M
$ RETURN
OAY =K -L
$ RETURN
DAY =K -L+31
$ RETURN
DAY= K -L +62
$ RETURN
OAY =K -L+90
$ RETURN
DAY =K -L +121
$ RETURN
OAY =K -L +151
$ RETURN
DAY =K -L +182
$ RETURN
DAY =K -L+212
$ RETURN
DAY =K -L +243
$ RETURN
DAY =K -L +274
$ RETURN
DAY =K -L +304
S RETURN
DAY =K -L +335
DAY =K -L+365
$ RETURN
GO TO
12
1
2
3
4
5
6
7
8
9
10
11
13
END
12
1
2
3
4
5
6
7
8
9
10
11
SUBROUTINE THEDATE(K,L,SMONTH,K1)
COMMON/YYY/ R,IDTE,MONTH
INTEGER SMONTH,DAY
JOAY = DAY(K,SMONTH)
M = JOAY + L - K1 - 1
GO TO 12
IF(M.GE.1.AND.M.LE.31)
GO TO
1
IF(M.GT.31.AND.M.LE.62)
GO TO
2
IF(M.GT.62.ANO.M.LE.90)
IF(M.GT.90.ANO.M.LE.121) GO TO 3
IF(M.GT.121.AND.M.LE.15i)GO TO 4
IF(M.GT.151.AND.M.LE.182)G0 TO 5
IF(M.GT.182.AND.M.LE.212)G0 TO 6
IF(M.GT.212.ANO.M.LE.243)G0 TO 7
IF(M.GT.243.AND.M.LE.274)G0 TO 8
IF(M.GT.274AND.M.L£.304)G0 TO 9
IF(M.GT.304.AND.M.LE.335)G0 TO 10
IF(M.GT.335.AND.M.LE.365)GO TO 11
$ MONTH =12
IDTE =M
$ MONTH =1
IDTE =M -31
$ MONTH =2
IDTE =M -62
$ MONTH =3
IDTE =M -90
$ MONTH =4
IDTE =M -121
IDTE =M -151
$ MONTH =5
$ MONTH =6
IDTE =M -182
$ MONTH =7
IDTE =M -212
$ MONTH =8
IDTE =M -243
$ MONTH =9
IDTE =M -274
$ MONTH =10
IDTE =M -304
IDTE =M -335
$ MONTH =11
END
SUBROUTINE IDAY (SMONTH,SDAY,MONTH,IDTE,JOAY,K)
INTEGER SMONTH,SDAY,DAY
.IDAY = DAY(SDAY,SMONTH)
JJDAY = DAY(IDTE,MONTH)
Page 84
$
á
1
$
$
$
$
$
$
$
$
$
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
RETURN
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
CHK
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
DAY
DAY
DAY
2
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
THEDATE
IDAY
IDAY
IDAY
IDAY
3
4
5
6
7
8
9
10
li
12
13
14
15
16
17
18
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
2
3
4
5
JDAY = JJDAY
i
2
C
C
C
G
C
G
JDAY +
IF(JDAY.LE.0)1,2
JDAY = JDAY + 365 + K
RETURN
IDAY
IDAY
IDAY
IDAY
IDAY
END
SUBROUTINE UNITS1(J)
UNITSI
UNITS1
THIS SUBROUTINE CONVERTS UNITS FROM MEQ /L TO UG /SEGMENT, OR
UNITSI
UG /SEGMENT TO MEQ /L AT ENTRY POINT UNITS2
UNITS1
UNITS1
UNITSI
UNITSI
COMMON /XXX /DELX,DELT,MM,START,B0(25 ),TEN(25 ),CHECK(25 ),MOISIN
UNITSI
1(25 ),CMH2O1(25 ),MOISOUT(25 ),AN03(25 ),ANH3(25 ),UREA(25 ),ORN
2(25 ),CÁ(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),SO4(25 UNITS1
3),E5(25 ),C5(25 ),SAS(25 ),XX5(25 ),CASO(25 ),AGSO(25 ),BNH4(25 ), UNITSI
4EC(25 ),CN1(25 ),SAMT(25 ),RN(25 ),RC(25 ),TEM(25 ),CAL(25 ),Q,CRO UNITSI
UNITS1
1P
UNITSI
CONVERT FROM MEQ/LITER TO UG /SEGMENT
UNITS1
ANH3(J) = ANH3(J) *CMH2O1(J) *14.0
UNITSI
ANO3(J) = AN03(J) *CMH2O1(J) *14.0
UNITSI
UREA(J) = UREA(J)*CMH 201(J) *28.0
UNITSI
CA(J) = CA(J) *CMH2O1(J) *20.04
UNITS1
ANA(J) = ANA(J) *CMH2O1(J) *22.99
UNITSI
AMG(J) = AMG(J) *CMH201(J) *12.16
UNITS1
UNITS1
HCO3(J) = HCO3(J) *CMH2O1(J) *61.0
UNITSI
CO3(J) = CO3(J) *CMH2O1(J) *30.0
UNITSI
CL(J) = CL(J) *CMH2O1(J) *35.46
SO4(J) = SO4(J) *CMH2O1(J)448.05
UNITSI
UNITS1
ORN(J) = ORN(J)*80(J) *DELX
SAMT(J) = SAMT(J) *9D(J) *DELX
UNITS1
UNITSI
RETURN
ENTRY UNITS2
UNITS1
UNITSI
UNITSI
CONVERT FROM UG /SEGMENT TO MEQ /LITER
ANH3(J) = ANH3(J) /(CMH2O1(J) *14.0)
UNITSI
ANO3(J) = AN03(J) /(CMH2O1(J) *14.0)
UNITS1
UREA(J) = UREA(J) /(CMH2O1(J) *28.0)
UNITS1
CA(J) = CA(J) /(CMH2O1(J) *20.04)
UNITS1
ANA(J) = ANA(J) /(CMH2O1(J) *22.99)
UNITSI
AMG(J) = AMG(J) /(CMH2O1(J) *12.16)
UNITS1
HCO3(J) = HCO3(J) /(CMH2O1(J) *61.0)
UNITS1
CO3(J) = CO3(J) /(CMH2O1(J) *30.0)
UNITSI
CL(J) = CL(J) /(CMH2O1(J) *35.46)
UNITS1
SO4(J) = SO4(J) /(CMH2O1(J) *48.05)
UNITS1
ORN(J) =ORN(J) /BO(J) /DELX
UNITSI
RETURN
UNITS1
UNITS1
END
SUBROUTINE OUTPT(K)
OUTPT
OUTPT
THIS SUBROUTINE WRITES PREDICTED TOTAL AND DELTA AMOUNTS FOR THE
OUTPT
OUTPT
COMPONENTS ANO VOLUMES ON TAPE2 (UNITS ARE EXPRESSED IN UG /UNIT
AND ML /UNIT AREA).
OUTPT
OUTPT
OUTPT
DIMENSION AMT(10),AMT1(10),DEL(10)
OUTPT
OUTPT
INTEGER Q,O,START,C ROP,TO
OUTPT
REAL MOISOUT
OUTPT
OUTPT
COMMON /SABLE /SUMS(3)
OUTPT
COMMON /XXX /DELX,DELT,MS,WTART,BD(25 ),TEN(25 ),CHECK(25 ),MOISIN
OUTPT
1(25 ),CMH2O1(25 ),MOISOUT(25 ),AN03(25 ),ANH3(25 ),UREA(25 ),ORN
OUTPT
2(25 ),Có(25 ),ANA(25 ),AMG(25 ),HCO3(25 ),CL(25 ),CO3(25 ),SO4(25
OUTPT
3),E5(25 ),C5(25 ),SA5(25 ),XX5(25 ),CASO(25 ),AGS0(25 ),BNH4(25 ), OUTPT
4EC(25),CN1(25 ),SAMT(25 ),_R_N(25 ),RC(25 ),TEM(25 ),CAL(25 ), Q,CRO OUTPT
K
CAREA
Page 85
6
7
8
9
10
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
_15_
1P, XTRACT, SUMN03, THOR (4),TO,IDAY,U(25),CH,CH1,IRERUN
C
ESTABLISH STATEMENT FUNCTION
SUBA(X,Y) = X *Y
IF(K.EQ.1) 1,2
C
ZERO INITIAL VALUES
SUMOUT = SUMOUTI = 0.0
00 3 I =1,10
AMT(I) = AMT1(I) = 0.0
1
3
GO TO
2
5
Y =
Z =
CMH2O1(Q)
MOISOUT(Q)
Y =
Z/Y
IF(Y.GT.1)
C
C
Y =1.0
SUM THE COMPONENTS
AMT(1) = SUMS(1)
AMT(2) = SUMS(2)
AMT(3) = SUMS(3)
AMT(4) = AMT(4) + SUBA(CA(Q),Y)
AMT(5) = AMT(5) + SUBA(ANA(Q),Y)
AMT(6) = AMT(6) + SUBA(A)!G(Q),Y)
AMT(7) = AMT(7) + SUBA(HCO3(Q),Y)
AMT(8) = AMT(8) + SUBA(CL(Q),Y)
AMT(9) = AMT(9) + SUBA(CO3(Q),Y)
AMT(10) = AMT(10) + SUBA(SO4(Q),Y)
SUM THE VOLUMES OUT
SUMOUT = SUMOUT + MOISOUT(Q)
IF(K.EQ.2)4,5
C
4
6
COMPUTE DELTA VALUES FOR COMPONENTS
00 6 1 =1,10
DEL(I) = AMT(I) - AMT1(I)
C
COMPUTE DELTA VALUE FOR VOLUME OUT
DELN = SUMOUT - SUMOUTI
C
WRITE SUMMATIONS AND DELTA VALUES ON TAPEZ
WRITE (2,100) SUMOUT,OELN,(AMT(I),DEL(I),I=i,10)
C
RESET VALUES FOR DELTA DETERMINATIONS
00 7 I =1,10
AMT1(I) = AMT(I)
SUMOUT1 = SUMOUT
7
5
K =3
C
RETURN TO MAIN PROGRAM
RETURN
100
FORMAT(IX,12E10.3)
END
Page 86
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
OUTPT
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
APPENDIX B
Sample Card Inputs
Page 87
CARD INPUTS FOR MOISTURE FLOW PROGRAM
1
1
1
1
5
2.
WATER APPLICATIONS
01/06 AMT=
WATER APPLICATIONS
01/15 AMT=
WATER APPLICATIONS
01/21 AMT=
WATER APPLICATIONS
02/06 AMT=
WATER APPLICATIONS
02/15 AMT=
WATER APPLICATIONS
02/21 AMT=
WATER APPLICATIONS 03/06 AMT=
03/15 AMT=
WATER APPLICATIONS
WATER APPLICATIONS
03/21 AMT=
WATER APPLICATIONS
04/15 AMT=
WATER APPLICATIONS
05/15 AMT=
WATER APPLICATIONS 06/15 AMT=
WATER APPLICATIONS
07/01 AMT=
WATER APPLICATIONS
07/15 AMT=
WATER APPLICATIONS
08/10 AMT=
WATER APPLICATIONS 09/15 AMT=
WATER APPLICATIONS
10/15 AMT=
WATER APPLICATIONS
11/06 AMT=
WATER APPLICATIONS
11/21 AMT=
WATER APPLICATIONS
12/01 AMT=
WATER APPLICATIONS
12/06 AMT=
WATER APPLICATIONS 12/21 AMT=
152. CM.
1 PANOCHE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
INITIAL MOISTURE CONTENT OF NODE
3.31
0.25
42,4
47.0
3.54
0.39
47.0
3.65
0.79
0.99
48,1
3.17
46.0
4.04
1.17
4.31
1.38
58.8
4.47
2.08
55,8
4.47
62.5
1.74
66.6
4.84
0.99
i.
i
3
100
22
5.
.38
.20
.07
.07
SOURCE =R
SOURCE =I
SOURCE =R
SOURCE =R
SOURCE =I
SOURCE =R
SOURCE =R
SOURCE =I
SOURCE =R
SOURCE =I
SOURCE =I
SOURCE =I
SOURCE =I
SOURCE =I
SOURCE =I
SOURCE =I
SOURCE =I
SOURCE =R
SOURCE =R
SOURCE =I
SOURCE =R
SOURCE =R
.61
.30
.91
.91
3.35
.61
.61
7.62
.30
4.88
8.44
12.80
7.92
7.92
11.58
6.71
5.18
.30
.61
.91
,61
.61
IF CC =1,
IF CC =1,
3 IF CC =1,
4 IF CC =1,
5 IF CC =1,
6 IF CC =1,
7 IF CC =1,
8 IF CC =1,
9 IF CC =1,
10 IF CC =1,
11 IF CC =1,
12 IF CC =1,
13 IF CC =i,
14 IF CC =1,
15 IF CC =1,
16 IF CC =1,
17 IF CC =1,
18 IF CC =1,
19 IF CC =1,
20 IF CC =1,
21 IF CC=1,
22 IF CC =1,
23 IF CC =1,
24 IF CC =1,
25 IF CC =1,
26 IF CC=1,
27 IF CC =1,
28 IF CC =1,
29 IF CC =1,
30 IF CC =1,
31 IF CC =1,
i
2
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Page 88
.21220
.21568
.21897
.22210
.22511
.22803
.23091
.23377
.23666
.23961
.24265
.24583
.24919
.25276
.25659
.26073
.26523
.27012
.27548
.28136
.28782
.29494
.30284
.31162
.32146
.33259
.34532
.36014
.36528
.37165
.38000
JAN -1
JAN -2
FEB -1
FEB -2
MAR -i
MAR -2
APR -1
APR -2
MAY -1
73.9
71.9
73.8
79.1
82.6
81.9
77.6
75.0
75.0
65.0
65.0
55.0
55.0
45.0
41.6
0.30
0.35
0.48
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
CONSUMPTIVE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
USE
5.16
5.03
5.03
4.94
5.27
4.63
4.94
4.22
4.22
3.80
4.06
3.42
3.42
3.22
3.43
0.24
0.26
0.20
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
(INCHES)
0.99
0.99
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.12
0.12
0,19
0.16
0.13
0.08
0.08
0.11
0.11
0.32
0.32
0.70
0.70
1.60
1.61
2.32
2.43
3.50
3.70
2.70
2.00
1.10
1.00
0.01
0.01
0.03
0.03
0.04
0.04
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
0.00
0.14
0.74
1.29
1.67
1.34
0.86
1.51
0.18
0.00
0.00
0.00
0.00
0,00
0.00
0.13
0.11
0.10
15 DAY
15 DAY
15 DAY
15 DAY
15 DAY
15 DAY
15 DAY
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
DAY
0.06
0.05
0.00
0.08
0.07
0.09
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
PERIODS
Page 89
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
FOR
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
COMPOSITE
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
CROP
MAY -2
JUN -1
JUN -2
JUL -1
JUL -2
AUG -1
AUG -2
SEP -i
SEP -2
OCT -1
OCT -2
NOV -1
NOV -2
DEC -i
DEC -2
KP- BARLEY
KP -MILO
KP -AVG.
JAN -1
JAN -2
FEB -1
FEB -2
MAR -i
MAR -2
APR -1
APR -2
MAY -1
MAY -2
JUN -1
JUN -2
JUL -1
JUL -2
AUG -1
AUG-2
SEP -1
SEP -2
OCT -1
OCT -2
NOV -1
NOV -2
DEC -i
DEC -2
CARD INPUTS FOR BIOLOGICAL- CHEMICAL PROGRAM
SAN LOUIS DRAIN RUN NO. 4 HALF FERTILIZER APPLICATION
5.
5.
0.0
0.
;.
1.
1.
.11.E -3
.1
15
53
5
3
3
0
0
10
10
1
1
10
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
1
10
1
20
30
46
152
92
61
8.89
8.89
8.89
8.89
10.00
10.00
10.00
10.00
12.22
12.22
12.22
12.22
12.22
15.56
15.56
15,56
15.56
18.89
18.89
18.89
18.89
22,22
22.22
22.22
22,22
22.22
24,044
24.44
24,44
24.44
23.33
23.33
23.33
23.33
23.33
21.11
21.11
21.11
21.11
16.67
16.67
16.67
16.67
12,22
12.22
12.22
12.22
12.22
49
10.00
50
10.00
51
10.00
52
10.00
53
10.00
.0035.0074
19.5
19.5
19.5
19.5
1
122
10.00
10.00
10.00
10.00
11.11
11.11
11.11
11.11
12.78
12.78
12.78
12.78
12.78
16.11
16.11
16.11
16.11
18.89
18.89
18.89
18.89
20.56
20.56
20.56
20.56
20.56
22.78
22.78
22.78
22.78
22.22
22.22
22.22
22.22
22.22
21.11
21.11
21.11
21.11
17.78
17.78
17.78
17.78
14.44
14.44
14.44
14.44
14.44
11.67
11.67
11,67
11.67
11,67
.97 1.63
0.0
0.1
0.1
0.1
152
16.67
16.67
16.67
16.67
15.56
15.56
15.56
15.56
16,67
16.67
16.67
16.67
16.67
17.78
17.78
17,78
17.78
18.89
1889
18.89
18,89
20006
20.06
20.06
20.06
20.06
21.67
21.67
21,67
21.67
22.22
22.22
22.22
22.22
22.22
21.11
21.11
21.11
21.11
20.06
20.06
20.06
20,06
18,89
18.89
18.89
18.89
18.89
17.78
17.78
17.78
17.78
17.78
.86 1.31 1.37
0,1
0.1
0.1
0.1
.02
300
300
300
300
.76
Page 90
0
1
1
1
19.5
19.5
19,5
19.5
19.5
19.5
19,5
029 .60
.015 1.06
.011 1.52
.012 1.58
.013 4.16
7
74
227
1
37.1
52.6
71.1
75,0
99,4
32.5
34.8
35.3
35.4
39.0
27.4
29.5
30.0
31.2
88.8
1.0
1.0
1.0
1.0
1.0
135
166
182
196
222
258
288
335
0,0 12,5 76,5
0.0 18,3 84,8
0.0 24,2103,7
105
166
135
0
0
2,75
10.6
7.65
10.6
5.30
6.30
0
22
23
24
6.3
10.2
18.3
30.2
42.9
258
0.1
0.1
0.0
0.0
0.0
196
2.0
1.8
1.7
1.1
222
46
15
21
2.3
1.5
2.2
3,8
0
0
14
15
16
17
18
19
20
2.2
15
0
10
11
12
13
0.0 11.9 31.7
0.0 10.0 53.4
0
0
02
03
04
05
06
07
08
09
0.1
0.1
0.1
0.1
0.1
0.1
0.1
12
0
01
0.1
0.1
0.1
0.1
0.1
0,1
0.1
30 2000
.48
74
15.2
.20
0,30
0.30
0.45
0.45
1,30
1.30
2.80
2.80
6.40
6.40
9.20
9.60
14.00
105
5.5
.13
300
300
300
300
300
300
300
.10
14.6(?
10.00
8.60
4,30
4.00
0.10
0,0
0.10
0.10
0,20
0.10
Page 91
.09
1.3 2135
1.3 1585
1.3 1278
1.3 1175
1,3 1132
5
S
S
5
5
APPENDIX C
Sample Printed Outputs
Page 93
PRINTED OUTPUT FROM MOISTURE FLOW PROGRAM
PARAMETERS, CONSTANTS, ANO INITIAL CONDITIONS USED IN THIS REPORT.
DIFFUSIVITY ANO CONDUCTIVITY RELATIONSHIPS MUST RE INSERTED INTO SOURCE DECK.
NOTE
RUN PARAMETERS, ANO ROUNOARY CONDITIONS.
TRC YEAR CROP
MM DPI
LL
AA
Pn
CC
1
1
1
WATER APPLICATION
6
DAY NUMPER
DAY NUMPER 15
NUMBER
21
DAY
DAY NUMPER 37
46
DAY NUMPER
DAY NUMPER 52
DAY NUMPFR 65
DAY NUMBER 74
80
DAY NUMPER
DAY NUMPER 105
DAY NUMPER 135
OAT. NUMPER 166
DAY NUMPER 182
DAY NUMPER 196
DAY NUMBER 222
DAY NUNPER 258
DAY NUMPER 788
DAY NUMPER 310
DAY NUMBER 325
DAY NUMPER 335
DAY NUMPER 340
DAY NUMPER 355
1
5
.38
.20
M
100
3
1
APPS DELx
22 5.00
DAYS, DATES, ANO AMOUNTS.
.61 CM.
AMOUNT=
GAZE
if 6
.30 CM.
AMOUNT=
DATE 1/15
.91 CM.
AMOUNT=
1/21
DATE
AMOUNT=
.91 CM.
DATE 2/ 6
AMOUNT=
3.35 CM.
DATE 2/15
AMOUNT=
.61 CM.
GATE 2/21
.61 CM.
AMOUNT=
PATE 3/ 6
7.62
CM.
AMOUNT=
OATE 3/15
AMOUNT=
.30 CM.
DATE 3/21
AMOUNT= 4.88 CM.
DATE 4/15
AMOUNT= 8.84 CM.
DATE 5/15
HATE 6/i5
AMOUNT= 12.80 CM.
AMOUNT= 7.92 CM.
DATE 7f 1
AMOUNT= 7.92 CM.
PATE 7f15
AMOUNT= 11.58 CM.
DATE 8/10
'ATE
AMOUNT= 6.71 CM.
1/15
AMOUNT=
5.18 CM.
DATE 10115
AMOUNT=
.30 CM.
RAT=_ 11/ 6
.61 CM.
AMOUNT=
PATE 11/21
AMOUNT=
.91 CM.
DATE 12/ 1
.61 CM.
AMOUNT=
OATE 12/ 6
.61 CM.
AMOUNT=
DATE 12/21
TS
TM
.38
.20
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
TO
.07
SM
.07
R
= I
=
=
R
= R
=
I
=
R
= R
=
=
=
I
R
I
=
I
=
I
=
I
=
I
=
I
=
I
=
=
I
R
= R
= I
= R
= R
SOIL IDENTIFICATION AND HORIZON DEPTHS.
DEPTH= 152.0
IOFNTIFICATION= PANOCHE
.
THETA
INITIAL SOIL MOISTURE CONDITIONS.
.218970
.215680
.212200
.249190
.245810
.242650
.302840
.294140
.287820
.380000
READ ACROSS THEN DOWN.
.230910
.228030
.225110
.265230
.260730
.256590
.345320
.332590
.321460
AT EACH DEPTH NODE,
.222100
.252760
.311620
CONSUMPTIVE USE DATA.
BLANEY- CRIDDLE DATA TO GET U
SEMI -MONTH
PCT -HV
K- CROP -1
K- CROP -2
AVG -TEMP
1
2
3
4
5
6
7
8
g
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
42.4
47.0
47.3
48.1
46.0
58.1
55.8
62.5
66.6
73.9
71.9
73.8
79.1
82.6
81.9
77.6
75.0
75.0
65.0
65.0
55.0
55.0
45.0
41.6
3.31
3.54
3.65
3.17
4.04
4.31
4.47
4.47
4.84
5.16
5.03
5.03
4.94
5.27
4.63
4.94
4.22
4.22
3.80
4.06
3.42
3.42
3.22
3.43
.25
.39
.79
.99
1.17
1.38
2.08
1.74
.99
.99
.99
0.00
1.00
0.00
0.00
0.00
0.00
1.110
0.00
0.00
0.00
0.00
.12
.12
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
.14
.74
1.29
1.67
1.34
.233770
.270120
.360140
.236660
.275480
.365280
U IF CROP =3 ONLY.
(CM /15 DAYS)
.20
.20
.28
.28
.81
.81
1.78
1.78
4.06
4.09
5.89
6.17
8.89
9.40
6.86
5.08
.86
2.79
2.54
.03
.03
.08
.08
1.51
.18
0.00
0.00
0.00
0.00
0.00
0.00
.10
.10
PERCENT OF ROOTS IN FACH OG TOP
6
FEET.
CROP =1
.300
.240
.190
.130
.080
.060
PERCENT OF ROOTS IN EACH OF TOP
6
FEET.
CROP =2
.350
.260
.160
.110
.070
.050
PERCENT OF ROOTS IN EACH OF TOP
6
FEET.
CROP =3
.480
.200
.130
.100
.090
-0.000
Page 94
.239610
.281360
.371650
DAILY OUTPUT,
INCLUDING THETA AT EACH DEPTH NODE
MONTH
YT
IDTE
1.003
1
1
.213607
.211192
.216853
.240999
.244296
.247778
.294633
.287415
.302604
.380900
II
1
DAILY OUTPUT,
INCLUDING THETA AT EACH
MONTH
XT
2
1.000
1
.211821
.208468
.242999
.239593
.287399
.294390
.380030
II
DAILY OUTPUT,
DAILY OUTPUT,
THETA AT EACH DEPTH NODE
MONTH
IDTE
3
1.000
1
3
.206967
.210266
.213448
.238396
.241899
.245597
.294192
.286840
.302276
.380001
XT
INCLUDING THETA
.219967
.251484
.311455
OPTION BB = 1.
CHECK
ETS
ET
OIF
.1431
-.0000
.3131
-.1563
.222985
.225944
.228878
.255453
.259730
.264358
.321353
.332519
.345282
IF PRINT OPTION 9B
CHECK
CL
.7486
.216546
.249526
.311220
.
XT
MCNTH
4
1.000
1
.274485
.236493
.286447
.380000
.234800
.274864
.365271
.237846
.280852
.371642
.233204
.274370
.365262
.236340
.280452
.371637
.231834
.273963
.365256
.235052
.280124
.371634
.230651
.273625
.365250
.233944
.279852
.371630
.229623
.273341
.365245
.232984
.279624
.371628
I
100
.230149
.268788
.360108
1.
ETS
ET
DIF
-.0000
.0394
-.4010
.3616
.222609
.225638
.219589
.263063
.253721
.258220
.332419
.345227
.321192
.208901
.240959
.294028
NOCE IF PRINT OPTION 8B = 1.
IDTE
CHECK
ETS
0IF
CL
ET
4
.4293
-.0000
.3525
-.4982
.4456
.212060
.218211
.221261
.215154
.224333
.244748
.257643
.262572
.248769
.253055
.302155
.311134
.321133
.332382
.345207
DAILY OUTPUT, INCLUDING THETA AT EACH DEPTH NODE IF PAINT OPTION 88 =
MONTH
II
XT
IOTE
CHECK
CL
5
I
101
.231823
.269385
.360120
I
100
.228708
.268295
.360099
AT EACH DEPTH
II
.205649
.2373+9
.286625
.380009
CL
.1381
DEPTH NOCE IF PRINT OPTION 88 = 1.
IOTE
CL
CHECK
ETS
ET
DIF
2
.2527
.2620
-.0000
.0262
-.2883
.215132
.224157
.227140
.218136
.221167
.246596
.250420
.263650
.254510
.258906
.302423
.332463
.345252
.311325
.321263
INCLUDING
IT
IF PRINT
1.100
5
1
.207698
.740152
.293891
.210837
.244021
.302054
.4974
.213929
.248123
.311062
.227458
.267883
.360091
1.
ETS
ET
DIF
.5167
-.0000
.3656
-.5823
.217000
.220078
.223192
.257155
.252489
.262157
.332352
.321084
.345190
Page 95
I
100
I
100
.226369
.267537
.360084
PRINTED OUTPUT FROM BIOLOGICAL- CHEMICAL PROGRAM
SAN LOUIS GRAIN RUN NO.
4
HALF FERTILIZER APPLICATION
CONTROL CARD SUMMARY
tBASIC PARAMETERS)
=
1
STARTING MONTH
=
1
STARTING DAY
RELATIVE STARTING DAY =
1
10
RELATIVE TERMIN DAY
= 15.0 CM
SOIL SEGMENT SIZE
=
.1O OAYS
TIME INTERVAL SIZE
5
NO. OF COMPONENT HRZNS=
3
=
NO. OF TEMP HRZNS
=
=
ISTOP
REDUCE
(I
1
=
1.0
=
=
3
1.00
= 0.00
.10
9
= .001
=
1.0
=
=
5.0
1
5.
-0 CONTROL PARAMETERS)
IREADP
ITEST
IMASS
IPRINTI
IPRINTJ
IPRINT
JPRINT
INK
IRERUN
IPUNCH
XTRACT
CROP
UPTAKEtNO3)
UPTAKEtNH4)
CONVERG1
CONVERG2
CHECK1
CHECK2
YEAR
=
0
o
10
1
1
INITIAL SOIL ANALYSEStMEGIL OF SOIL EXTRACT) -- tORG=UG /GM OF SOIL)
HZN
1
2
3
4
S
NH3
.029
.015
.011
.012
.013
NO3
.600
1.060
1.520
1,580
4.160
UREA
0.000
0.000
0.000
0.000
0.000
SEG
NH3
NO3
2
7.917
7.917
4.095
4.095
3.003
3.003
3.276
3.276
3.549
3.549
163.800
163.800
289.380
289.380
414.960
414.960
431.340
431.340
1135.680
1135.680
3
4
S
6
7
8
9
10
11
CA
NA
MG
11.900
10.000
12.500
18.300
24.200
31.700
53.400
76.500
84.800
103.700
2.200
1.500
2.200
3.800
5.500
1278.000
1175.000
1132.000
TRANSFORMED SOIL ANALYSES(UG /SEGMENT
UREA
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
ORG
2135.000
1585.000
HCO3
2.300
2.000
1.800
1.700
1.100
6.300
10.200
18.300
30.200
42.900
HCO3
2735.850
2735.850
2379.000
2379.000
2141.100
2141.100
2022.150
2022.150
1308.450
1308.450
4356.261
4356.261
7052.994
7052.994
12653.901
12653.901
20882.394
20882.394
29664.063
29664.063
CL
CO3
.100
.100
0.000
0.000
SO4
0.000
97.100
52.600
71.100
75.000
89.400
CO3
58.500
58.500
58.500
58.500
0.000
0.000
0.000
0.000
0.000
0.000
34751.772
34761.772
49284.885
49284.885
66618.922
66618.922
70273.125
70273.125
83765.565
83765.565
OF SOIL)
ORG
41632.500
41632.500
30907.500
30907.500
24921.000
24921:000
22912.500
22912.500
22074.000
22074.000
CA
NA
MG
4650.282
4650.282
3907.800
3907.800
4884.750
4884.750
7151.274
7151.274
9456.876
9456.876
14211.268
14211.268
23939.487
23939.487
34295.332
34295.332
38016.264
38016,264
46489,228
46489.228
521.664
521.664
355.680
355.680
521.664
521.664
901.056
901.056
1304.160
1304.160
Page 96
CL
SO4
WEEKLY TEMPERATURE DATA
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
3H
39
40
41
42
43
44
45
4h
47
49
49
50
51
52
53
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATUREIDEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPFRATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPF,RATURE(DEG
TEMPERATUREfDEG
TEMPERATUREfDEG
TEMPERATUREfDEG
TEMPERATURE(DEG
TEMPFRATURE(DEG
TEMPERATURE(DEG
TEMPERATUREfDEG
TEMPFRATURE(DEG
TEMPFRATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPFRATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(OEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPFRATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPFRATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPERATUREfDEG
TEMPERATURE(DEG
TEMPERATUREfDEG
TEMPERATURE(DEG
TEMPERATURE(DEG
TEMPFRATURE(DEG
HORIZON DEPTH(CM)
46.0
20.0
152.0
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C>=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C):
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C1=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
C)=
8.9
8.9
0.9
8,9
10.0
10.0
10.0
10.0
12.2
12.2
12.2
1262
12.2
15.6
15.6
15.6
15.6
18.9
18.9
19.9
18.9
22.2
22.2
22. 2
22.2
22.2
24.4
24.4
24.4
24.4
23.3
23.3
23,3
23.3
23.3
21.1
21.1
21.1
21.1
16.7
16.7
16.7
16.7
12.2
12.2
12.2
12.2
12.2
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
11.1
11.1
11.1
11.1
12.8
12.8
12.8
12.8
12.8
16.1
16.1
16.1
16.1
18.9
18.9
19.9
18.9
20.6
20.6
20.6
20.6
20.6
22.8
22.8
22.8
22.8
22.2
22.2
22.2
22.2
22.2
21.1
21.1
2101
21.1
17.8
17.8
17.8
17.8
14.4
14.4
14.4
14.4
14.4
11.7
11.7
11.7
11.7
11.7
16.7
16.7
16.7
16.7
15.6
15.6
15.6
15.6
16.7
16.7
16.7
16.7
16.7
17.8
17.8
17.8
17.8
18.9
18.9
18.9
19.9
20.1
20.1
20.1
20.1
20.1
21.7
21.7
21.7
21.7
22.2
22.2
2 2.2
22.2
22.2
21.1
21.1
21.1
21.1
20.1
20.1
20.1
20.1
18.9
18.9
18.9
19.9
18.9
17.8
17.8
17.8
17.8
17.8
Page 97
IRRIGATION WATER ANALYSIS(PPM)
NH4
NO3
CA
NA
.05
.10
19.44
37.47
IRRIGATION APPLICATION DATES
74
46
15
135
105
182
166
HCO3
79.91
MG
10.46
196
222
CL
48.58
SO4
.60
36.52
335
288
258
CO3
FERTILIZER APPLICATION DATES
74
135
105
196
166
222
258
FERTILIZER APPLICATIONS(UG)
UREA
NO3
NH4
DEPTH
6
0.0
0.0
0.0
0.0
0.0
-0.0
7
-0.0
1
2
3
4
5
0.0
24.0
92.5
66.8
92.5
46.3
55.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
76.2
0.0
0.0
0.0
0.0
0.0
0.0
CA
0.0
0.0
0.0
(1.0
0.0
0.0
0.0
CO3
0.0
0.0
0.0
SO4
0.0
0.0
0.0
0.0
0.0
0.0
0.0
no
0.0
0.0
n.0
ORGANIC -N APPLICATION DATES
227
ORGANIC
DEPTH
15.0
1
N
APPLICATIONS(UG)
C/N
30.0
ORN
299.2
30.0
COMPONENT HORIZON DEPTHSICM)
92.0
61.0
122.0
152.0
PLANT NITROGEN UPTAKE DATA INPUT FROM CARDS
ROOT DISTRIHUTION
35.5
35.5 CM
0
61.0 CM
.20
.48
61.0
-
91.5 CM
.13
91.5
+
122 CM
.ln
TOTAL PLANT UPTAKE OF NITROGEN(UG /15 DAYS)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
3.37
3.37
5.05
5.05
14.59
14.59
31.42
31.42
71.82
71.82
103.24
107.73
157.10
163.83
112.21
96.50
48.25
44.89
1.12
0.00
1.12
1.12
2.24
1.12
Page 98
153 CM
122
.09
153 CM
-0.00
SUMMARY OF NITROGEN BALANCE FOR SYSTEM
INITIAL NITROGEN CONTENT =
.280200E +05
UG
0.
TOTAL -N ADDED TO SYSTEM =
UG
=
FROM
SYSTEM
.588089E +q2 UG
TOTAL -N LEACHED
TOTAL -N UPTAKE BY PLANTS =
.280748E+00 UG
TOTAL INPUT - TOTAL OUTPUT FOR N =
-.590297E +02
CHANGE IN N STORAGE SINCE START OF RUN = -.590297E +02
TOTAL -N UPTAKE BY PLANTS(ATTEMPTED) =
UG
UG
.220748E +00
UG
DAY=
TIME_ INTERVAL=
10
10
PREDICTED AMOUNTS(UG /SEGMENT OF SOIL)-- (SEGVOL =CC WATER /SEG SOIL)
SEG
NH3
n!03
2
3
.330
.585
.583
138.771
206.347
277.867
284.809
355,359
389.616
406.515
412,544
850.529
1068.931
4
5
6
7
8
9
10
11
3.854
4.337
4.867
5,673
5.852
3.411
3.874
UREA
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
ORI)
CA
NA
MG
3331.116
3331.176
2473.194
2470.311
1992.067
1992.061
1831.596
1831.595
1764.259
1764.194
7354.232
7131.126
6712.354
6566.516
6498.992
6488.688
6832.366
7014.843
7239.611
7336.926
8498.387
12879.167
19815.098
23001.483
29982.601
33306.300
36362.157
37648.203
43025.682
45687,954
770.223
793.152
616.708
594.577
687.911
693.118
866.063
890.083
1031.582
1052.608
SUMMARY OF NITROGEN BALANCE FOR SYSTEM
INITIAL NITROGEN CONTENT =
.280200E+05 U0
UG
TOTAL -N ADDED TO SYSTEM =
O.
.576270E +03
UG
TOTAL -N LEACHED FROM SYSTEM =
PLANTS
UG
=
.220748E +01
TOTAL -N UPTAKE BY
-.578477E +03
TOTAL INPUT - TOTAL OUTPUT FOR N =
CHANGE IN N STORAGE SINCE START OF RUN _ -.578477E +03
TOTAL -N UPTAKE BY PLANTS(ATTEMPTED)
=
UG
UG
.220748E +01
UG
Page 99
HCO3
1636.079
2479.418
2481.198
2407.431
2241.625
2164.014
2073.614
2033.740
1597.183
1375.567
CL
2605.108
3947.947
5903.265
6792.240
10360.982
12123.914
17489,728
20100.826
26008.894
28825.785
SO4
33564.266
39762.954
49898,539
54974.606
65124.061
69767.130
70469.308
70?15.117
.010 74857.791
.001 77097.161
CO3
34,984
53.017
57.618
58.393
23.506
5,482
.882
.107
ENH4
4,277
5.000
5.912
33.8]6
35.613
35.952
35.788
35,629
20.887
22.434
5EGVOL
19.500
19.500
19.500
19.500
19.500
19.500
19.500
19.500
19.500
19.500
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