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Andersson, A., Meier, H M., Ripszam, M., Rowe, O., Wikner, J. et al. (2015)
Projected future climate change and Baltic Sea ecosystem management.
Ambio, 44(Suppl 3): S345-S356
http://dx.doi.org/10.1007/s13280-015-0654-8
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AMBIO 2015, 44(Suppl. 3):S345–S356
DOI 10.1007/s13280-015-0654-8
Projected future climate change and Baltic Sea ecosystem
management
Agneta Andersson, H. E. Markus Meier, Matyas Ripszam, Owen Rowe,
Johan Wikner, Peter Haglund, Kari Eilola, Catherine Legrand,
Daniela Figueroa, Joanna Paczkowska, Elin Lindehoff, Mats Tysklind,
Ragnar Elmgren
Abstract Climate change is likely to have large effects
on the Baltic Sea ecosystem. Simulations indicate 2–4 °C
warming and 50–80 % decrease in ice cover by 2100.
Precipitation may increase *30 % in the north, causing
increased land runoff of allochthonous organic matter
(AOM) and organic pollutants and decreased salinity.
Coupled physical–biogeochemical models indicate that, in
the south, bottom-water anoxia may spread, reducing cod
recruitment and increasing sediment phosphorus release,
thus promoting cyanobacterial blooms. In the north,
heterotrophic bacteria will be favored by AOM, while
phytoplankton production may be reduced. Extra trophic
levels in the food web may increase energy losses and
consequently reduce fish production. Future management
of the Baltic Sea must consider the effects of climate
change on the ecosystem dynamics and functions, as well
as the effects of anthropogenic nutrient and pollutant load.
Monitoring should have a holistic approach, encompassing
both autotrophic (phytoplankton) and heterotrophic (e.g.,
bacterial) processes.
Keywords Climate change Allochthonous organic matter Primary production Bacterial production Food web Monitoring
INTRODUCTION
The Baltic Sea is exposed to many stressors, e.g., eutrophication, organic pollutants, overfishing, invasive species, and acidification. Of these disturbances, eutrophication
Electronic supplementary material The online version of this
article (doi:10.1007/s13280-015-0654-8) contains supplementary
material, which is available to authorized users.
is presently considered to have the most severe effects in the
Baltic proper, while organic pollutants are the largest environmental problem in the Gulf of Bothnia. Climate change
may worsen these problems and it is thus a challenge to try
to understand how different basins of the Baltic Sea may be
influenced and how to appropriately manage this vulnerable
ecosystem.
Climate change, induced by anthropogenic emissions of
greenhouse gasses, is expected to have a significant impact
on the Baltic Sea (BACC I author team 2008; BACC II
author team 2015). A warming trend is already evident in
the Baltic region and will continue through the twenty first
century. Due to the large variability of the climate system,
only temperature and directly related variables, such as ice
conditions, are likely to show statistically significant
changes in the next few decades, whereas significant effects in the water cycle can only be expected later in the
century.
The impact of climate change on the Baltic Sea environment can be estimated with the help of coupled physical–
biogeochemical models in conjunction with downscaling
techniques that link projected global climate change to regional scales (e.g., Meier et al. 2011a). However, Baltic Sea
ecosystem projections suffer from the biases of global and
regional climate models, uncertainty in greenhouse gas
emissions, nutrient load scenarios, and ecosystem responses,
as well as natural climate variability. Hence, ensemble
simulations are essential to estimate uncertainties in the
projections (e.g., Meier et al. 2006, 2011a).
When assessing the effects of climate change on marine
ecosystems, it is important to understand the driving
mechanisms for biological and chemical processes. These
drivers can influence the marine ecosystem in a variety of
ways, altering food web community structure, overall
productivity, and the transport of pollutants. Such changes
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are of great significance for the health and sustainability of
the marine ecosystem. In this study, we have therefore
combined information from field and experimental studies
with modeling simulations, to try to understand the effects
of climate change on the Baltic Sea ecosystems.
PHYSICAL CHANGES
Model simulations indicate that the surface water layer will
warm more than the deep water in all sub-basins (Meier
et al. 2012b). Sea surface temperature (SST) changes are
projected to be the largest in the Bothnian Bay and the
Bothnian Sea during summer and in the Gulf of Finland
during spring. According to Meier et al. (2012a), the mean
summer SST will increase by about 2 °C in the southern
and 4 °C in the northern Baltic Sea by the end of this
century. The larger warming in the north is caused at least
partly by the ice-albedo feedback (Meier et al. 2011b).
Under a more optimistic scenario, the average SST may
increase by only 1 °C (Neumann 2010).
The future reduction of the ice cover depends mainly on
projected air temperature changes over the Baltic Sea in
winter, whereas the other drivers, like wind speed, are less
important (e.g., Meier et al. 2004). Despite substantial
uncertainties, all available scenario simulations indicate a
50–80 % decrease in sea ice extent by 2100 (Meier 2006).
This increase in open water conditions will influence
winds, wave climate, and underwater light conditions
(Eilola et al. 2013). Wave height is projected to increase in
spring in large parts of the Gulf of Finland, the Bothnian
Sea, and the Bothnian Bay; and mean spring irradiance
may increase in previously ice-covered areas. Significantly
increased well-mixed layer depths are expected in most of
the Bothnian Bay and the Gulf of Finland.
Sea surface salinity (SSS) will change less in the
northern and eastern Baltic Sea (least in the Bothnian Bay)
and most in the Danish straits region, especially the Belt
Sea (Fig. 1) (Meier et al. 2012a), through shifting salinity
fronts in the transition zone. The SSS changes are rather
uniform across the seasons. In the ensemble mean, salinity
in the strongly stratified Bornholm and Gotland basins
decreases by 1.5–2 salinity units at all depths (Meier et al.
2012b). In the less strongly stratified Gulf of Finland and
Bothnian Bay, salinity changes are larger in the deep water,
reducing the vertical stability. These results are rather
consistent among various Baltic Sea models. The largest,
model-related uncertainty was found for projected halocline depth in the Baltic proper (Meier et al. 2012b).
Salinity changes (Fig. 1) are caused by changes in runoff, which in the depicted scenario simulations is projected
to increase by 15–22 % (Meier et al. 2012a). Although all
scenario simulations suggest either unchanged or decreased
123
salinity compared to present climate (Meier et al. 2006),
projections have large uncertainties due to variability
among regional Baltic climate models in water balance
(e.g., Kjellström and Lind 2009), wind projections (Kjellström et al. 2011; Nikulin et al. 2011), runoff projections
using various hydrological models, and also bias in correction methods for air temperature and precipitation
(Meier et al. 2012b; Donnelly et al. 2014).
Overall stratification changes in the Baltic proper are
expected to be small because the greater freshwater supply
will increase recirculation of brackish surface waters and
consequently reduce saltwater influx to the Baltic Sea
(Meier 2005). Changes in wind-induced mixing are more
important for stratification changes in the Baltic proper
than changes in runoff (Meier 2005).
Saltwater inflows from the Kattegat influence average
salinity, vertical stratification, and deep water oxygen
conditions in the Baltic Sea (e.g., Meier and Kauker 2003).
Still Gräwe et al. (2013) found no clear tendency for salt
water transport to change in the future climate, either
during medium or major inflow events. Schimanke et al.
(2014) estimated that atmospheric events favorable for
major Baltic inflows may become slightly more common.
All published scenario simulations share the weakness that
they have not considered the effect of global sea-level rise
on saltwater inflows. Unpublished research by H.E.M.
Meier et al. indicates that if the global mean sea level rises
by 1.5 m, then the effect on salinity and stratification
cannot be neglected.
PELAGIC FOOD WEB STRUCTURE FROM NORTH
TO SOUTH
To evaluate the effects of climate change on the marine
food web, it is crucial to understand the mechanisms
regulating food web structure and productivity. Bacteria
and phytoplankton are key organisms at the base of the
marine food web, providing biomass production on which
the rest of the food web relies. They take up nutrients via
diffusion and are thus the first organisms to respond to
changes in nutrient availability. Their interaction strongly
influences the structure and efficiency of the food web and
hence production at higher trophic levels.
Phytoplankton primary production increases strongly
basin by basin from north to south in Baltic Sea offshore
waters and is almost tenfold higher in the Baltic proper
than in the Bothnian Bay (Fig. S1). The low primary production in the Bothnian Bay is caused by a combination of
strong phosphorus (P) limitation (Andersson et al. 1996), a
short productive season and a poor light climate for phytoplankton. The Bothnian Bay water is relatively brown,
with twice the concentration of humic substances and
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AMBIO 2015, 44(Suppl. 3):S345–S356
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Fig. 1 Projected seasonal (DJF = December to February, MAM = March to May, JJA = June to August, SON = September to November) and
annual mean ensemble average sea surface salinity changes (in g kg-1) from 1978–2007 to 2069–2098 (from Meier et al. 2012a)
*70 % lower phosphorus concentration compared to the
Baltic proper (Fig. S1).
The annual bacterial biomass production, on the other
hand, is rather uniform from north to south, although its
relative share of the total production varies among the
basins. In offshore waters of the Bothnian Bay, the Bothnian Sea, and the Baltic proper, the bacterial production
equals 70, 30, and 12 % of the primary production, respectively (Fig. S1). The large importance of bacteria in the
north may partly be due to high concentrations of allochthonous organic matter (AOM), e.g., humic substances, which fuel bacteria with external organic matter
(Sandberg et al. 2004). Another contributing factor can be
low nutrient availability (P), as phytoplankton might exude
more of their photosynthetic products when nutrients are
scarce. These photosynthetic exudates are then channeled
into bacterial production.
DRIVERS OF COASTAL PRODUCTION
Field studies were performed during the spring period in
three estuaries in the Baltic Sea, in order to find out how
the river inflow influences primary and bacterial
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production. In the Öre estuary, Gulf of Bothnia, primary
production was stimulated by increased phosphorus
availability and hampered by high concentration of dissolved organic carbon (DOC) (Table S1). DOC, humic
substances, and colored dissolved organic matter
(CDOM) are all measures of allochthonous organic matter, which is transported from land to the Baltic Sea via
rivers, reducing light penetration in coastal waters (Pettersson et al. 1997). In the nitrogen-limited Emån estuary,
in the southern Baltic Sea, the spring primary production
was negatively related to phosphorus and temperature
(Table S1).
Bacterial production was mainly controlled by factors
that are likely to be influenced by climate change. A
stimulation by humic substances and DOC was observed
in the coastal areas of the Gulf of Bothnia (Råne and
Öre estuaries) (Table S1). Even though the bioavailable
fraction of the AOM in short-term experiments is small
(Stepanauskas et al. 2002; Lignell et al. 2008), the large
AOM export via rivers to the coastal zone, combined
with increased bioavailability by, e.g., photochemical
processes over longer time scales, makes AOM a major
driver of bacterial production in the northern Baltic Sea
(Sandberg et al. 2004). In the study area in the southern
Baltic Sea, however, regression analysis indicated temperature as the major factor influencing bacterial production (Table S1). This agrees with previous studies in
the Baltic Sea, indicating that bacterial production is
temperature limited below ?6 to ?8 °C, but substrate
limited (by inorganic nutrients or organic C) at higher
temperatures (e.g., Autio 1998).
EFFECTS OF INCREASED DISSOLVED ORGANIC
MATTER INFLOW ON COASTAL PRODUCTION
An integrated understanding of the effects of the projected
increase in runoff in the northern Baltic Sea is required.
The fertilizing effect of nitrogen and phosphorus discharged by rivers has been the main issue in recent research
(Smith 2006; Finkel et al. 2010). Nutrient-rich freshwater
discharge can lead to eutrophication, with increased phytoplankton growth, oxygen consumption, hypoxia, and reduced recreational value of the coastal zone. However,
freshwater discharge also has other potential effects on the
hydrography, chemistry, and biology of the marine environment. Dissolved organic matter (DOM) is a major
chemical constituent of river water, with potential effects
in coastal areas. Colored humic substances degrade the
light climate, heat the near-surface water (Cole et al. 1992;
Howarth et al. 2000; Ask et al. 2009), and can also act as a
carbon source for bacterioplankton production (Wikner
et al. 1999).
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Using a 13-year ecological time-series from the Bothnian Bay, the Bothnian Sea, and the Öre estuary, Wikner
and Andersson (2012) studied the effect on the trophic
balance of a 4-year period (1998–2001) with elevated river
discharge. The ratio between phytoplankton and bacterial
production was used as an index of trophic balance. Correlation analysis indicated that increased freshwater discharge of colored DOM reduced the primary production,
while bacterial production remained stable. Previous
studies have shown that part of the riverine DOM can be
assimilated by bacterioplankton (Zweifel et al. 1995;
Wikner et al. 1999). This suggested a dual effect of riverine
DOM on the trophic balance, by reducing light (i.e., energy) supply to photosynthetic organisms, and simultaneously stimulating heterotrophic organisms by providing an
alternative carbon and energy source. It is likely that the
food web efficiency decreased during this period, since
bacteria-based food webs generally have more trophic
levels than those based on phytoplankton (Berglund et al.
2007). However, in a climate change experiment combining increased input of humic substances with higher temperature, the food web efficiency was not reduced when the
planktivorous fish was the three-spine stickleback (Gasterosteus aculeatus), which is able to adapt to high temperature and can exploit the system efficiently (Lefébure
et al. 2013).
Benthic zones are often important contributors to overall
production in shallow coastal waters. During the 1998–
2001 period of elevated river flow and lower pelagic primary production, the native benthic amphipod Monoporeia
affinis declined drastically in the Gulf of Bothnia (Eriksson-Wiklund and Andersson 2014), probably due to food
shortage, since settling phytoplankton is its main food
source. In the virtual absence of this amphipod, the nonnative polychaete Marenzelleria spp. invaded the area.
Such changes in species composition alter food web
structure and resource use and can modify the transport and
release of pollutants.
EFFECTS OF INCREASED DOC INFLOW ON
ORGANIC POLLUTANT SORPTION AND
BIOACCUMULATION
The seasonal export of hydrophobic organic contaminants
from soils to river water peaks during the spring flood, and
is connected to processes determining DOC release at the
soil–water interface (Bergknut et al. 2010). Climate-induced increases in precipitation and DOC release are
therefore likely to cause increased inflow of contaminants
to coastal areas.
Higher concentrations of DOC in the seawater may also
affect the fate of the pollutants, e.g., by changing the
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AMBIO 2015, 44(Suppl. 3):S345–S356
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Fig. 2 Log KDOC values for hexachlorobenzene (black), phenanthrene (squared), and tributyl phosphate (striped) at different locations in the
Baltic Sea. Water samples were collected along a north–south gradient in August 2013, filtered to retrieve the dissolved fraction, and spiked with
different organic pollutants. Error bars represent the standard deviation of data from four sampling points in each basin
effects on their solubility, volatilization, long-range transport, transformations, and bioavailability (e.g., Kukkonen
et al. 1990; Poerschmann and Kopinke 2001). In a spiking
experiment, we demonstrated that the sorption of structurally diverse pollutants to dissolved organic matter in
seawater varies between areas of the Baltic Sea (Fig. 2)
(Ripszam et al. 2015). The distribution constant between
water and DOC (log KDOC) for hexachlorobenzene and
phenanthrene, representing halogenated aromatic and
polycyclic aromatic compounds, respectively, decreased
from north to south in the Baltic Sea, while tributyl
phosphate, representing compounds with polar functional
groups and relatively high water solubility, showed no
geographical variation. The salinity gradient in the study,
from 2.8 to 6.6, probably had only a minor effect on the
partitioning of the tested organic pollutants (Engebretson
and von Wandruszka 1994; Kuivikko et al. 2010).
Considering the small variation of DOC concentration in
the offshore Baltic Sea (4.2–5.2 mg C/l), we propose that
differences in quality, i.e., the terrestrial component of the
DOC, caused the differences in log KDOC values.
SCENARIOS FOR ECOSYSTEM CHANGES
The combined influence of changing climate, eutrophication, acidification, and overfishing on the marine
ecosystem has been studied with coupled physical–biogeochemical–carbonate models (e.g., Neumann 2010;
Meier et al. 2011a, b; Neumann et al. 2012; Omstedt et al.
2012) and food web models (e.g., Niiranen et al. 2013).
However, models coupling lower and higher trophic
levels do not exist, and our knowledge of the effects of
changing climate and other anthropogenic drivers on the
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Fig. 3 Conceptual model of climate-induced ecosystem changes in the Gulf of Bothnia by 2100. Illustration: Kristina Viklund and Mattias
Pettersson
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Fig. 4 Conceptual model of climate-induced ecosystem changes in the Baltic Proper by 2100. Illustration: Kristina Viklund and Mattias
Pettersson
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marine ecosystem is still very limited. Eilola et al. (2011)
compared three physical–biogeochemical Baltic Sea
models and identified four major sources of uncertainty:
(1) uncertain initial conditions, (2) unknown bioavailability of nutrients in land runoff, (3) unreliable parameterization of sediment fluxes and turnover of
nutrients in the sediments, and (4) lack of process understanding in the Gulf of Bothnia. In addition, the possible influence of genetic adaptation is currently
unpredictable. Nevertheless, projected future hydrographic conditions such as mixing depth, light penetration, vertical exchange of nutrients and oxygen, and deep
water ventilation will very likely affect biogeochemical
cycles and consequently also the entire ecosystem. Given
the projected changes in the abiotic environment and
biogeochemical processes, we cautiously suggest some
likely future changes in the marine ecosystem.
Ice cover is expected to decrease in the northern Baltic
Sea, causing an earlier onset of the spring bloom by up to
1 month (Fig. 3), and increased wind- and wave-induced
resuspension will hasten the transport of nutrients from the
coastal zone to the open sea (Eilola et al. 2013). Increased
river runoff will lead to higher concentrations of AOM,
which reduces light penetration in the water and potentially
also primary production (Wikner and Andersson 2012;
Lefébure et al. 2013). The AOM provides an alternate
carbon source for heterotrophic bacteria as compared to
phytoplankton-derived substrates, which may increase
bacterial activity, making bacteria outcompete phytoplankton for inorganic nutrients. The poorer light climate
and increased competition from bacteria may decrease
phytoplankton production (Lefébure et al. 2013). Although
the spring bloom occurs earlier due to earlier ice break-up,
primary production does not necessarily increase according
to modeling results (Eilola et al. 2013). Should the yearly
primary production decrease, it is likely that the production
will decrease also at higher trophic levels. The food web
will get an additional intermediate trophic level, which will
cause increased respiration and excretion losses (Fig. 5),
most likely causing decreased production of zooplankton,
benthos, and fish. Because water absorbs less oxygen at
higher temperature, oxygen concentration in the water will
be reduced, and increased AOM will stimulate bacterial
respiration, further reducing the oxygen concentration
(Panigrahi et al. 2013). Decreased light availability may
favor tactile over visual predators. Taken together, field
observations in the coastal zone (data presented here),
experimental studies (e.g., Lefébure et al. 2013), and longterm, large-scale studies (Wikner and Andersson 2012)
indicate that the base of the food web, i.e., the phytoplankton and bacteria, can become significantly altered if
climate change increases inputs of AOM to the Gulf of
Bothnia.
123
In the Baltic proper, increased nutrient loads and higher
temperatures may intensify internal nutrient cycling (Meier
et al. 2011a), potentially increasing both primary production and oxygen consumption (Fig. 4). This may possibly
increase phosphorus mobility and reduce denitrification
efficiency (Meier et al. 2012b). Without drastic nutrient
load abatements, hypoxic and anoxic areas are projected to
increase (Meier et al. 2011a) and cause intensified exchange of nutrients between shallow and deeper waters
(Eilola et al. 2012).
Scenario simulations suggest that the rising atmospheric
CO2 will control future pH changes in the surface water
and that eutrophication will not affect the mean pH (Omstedt et al. 2012). Climate warming may lead to earlier and
more frequent cyanobacterial blooms, as already observed
for surface accumulations of cyanobacteria (Kahru and
Elmgren 2014) and perhaps also to increased nitrogen
fixation (Meier et al. 2012b; Neumann et al. 2012; Hense
et al. 2013). Nitrogen-fixing cyanobacteria will supply the
ecosystem with plant-available nitrogen, but, as they are of
poor food quality for consumers, the efficiency of energy
transfer to higher trophic levels may be reduced (Fig. 5).
A lower salinity may reduce or eliminate cod spawning
areas, reducing the value of the fish catch (Fig. 4). Anoxia
will reduce the production of benthic fish food. A lower
salinity will eliminate many marine species, but allow
more freshwater species to colonize the ecosystem. A decrease in salinity will inevitably change species composition and therefore ecosystem function (e.g., through the
loss of filter-feeding bivalves). Most food-web and fish
population models indicate that cod fishing will remain an
important determinant of the cod stock in the future,
although climate effects may be substantial. Eutrophication
has, however, been suggested to be of minor importance
for the cod stock size (Niiranen et al. 2013).
Climate change may directly benefit invasive species by
providing conditions nearer to those in their native ranges,
e.g., warmer temperatures. Furthermore, invasive species
tolerant of low-oxygen conditions may be favored, such as
Marenzelleria spp. (Maximov 2011). As these polychaetes
burrow deep into sediments (30 cm), they can stimulate
release and subsequent bioaccumulation of buried organic
pollutants (Josefsson et al. 2010, 2011).
In a future climate, halogenated aromatic and polycyclic
aromatic pollutants may be sorbed to DOC to a greater
extent. Whether this will increase or reduce their availability to marine organisms is unknown. Since DOC is
partly utilized by bacteria as a food source, we hypothesize
an increased transport of DOC-associated pollutants up the
food web via microbes (Wallberg et al. 2001). On the other
hand, high concentrations of humic substances in lakes
have been shown to make persistent organic pollutants less
available for uptake by fish (Larsson et al. 1992).
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AMBIO 2015, 44(Suppl. 3):S345–S356
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IMPLICATIONS FOR MANAGEMENT OF THE
BALTIC SEA
Fig. 5 Simplified schematic view of climate-altered food webs in the
Bothnian Bay (upper), southern Bothnian Sea (mid), and Baltic proper
(lower) in summer. Green arrows represent autochthonous and brown
arrows allochthonous production. Organisms included in the food
webs and their trophic position (in parenthesis); bacteria (1, 2),
phytoplankton (1), flagellates (2, 3), ciliates (3, 4), zooplankton (2, 4,
5), and fish (3, 5, 6). Illustration by Mats Minnhagen
Considering the complex and interactive alterations climate
change may induce in the Baltic Sea ecosystem, it is crucial
that future Baltic Sea management takes these aspects into
consideration. During recent decades, the Baltic countries
have agreed on joint goals for the management of the
Baltic Sea environment. Compliance monitoring has been
used to classify the ecological state of marine waters (e.g.,
Anon 2007), but is not yet focused on climate change,
which interacts with other ecosystem changes and
exposures.
One example is chlorophyll a, a proxy for phytoplankton
biomass, which should respond significantly to nutrient
loading. The chlorophyll content in algae is, however,
highly variable depending on, e.g., species composition
and local light climate, which in turn are affected by AOM
in the water. An increased AOM load is likely to promote
bacterial production, but decrease primary production, as
described above. The oxygen concentration may decrease
and the ecosystem may become more heterotrophic. The
food web will acquire extra trophic levels, leading to
greater energy losses and decreased fish production. We
therefore suggest that not only primary production but also
bacterial production should be monitored in the Baltic Sea.
Management should also consider the effects of temperature and DOC on hypoxia, and thus not only interpret
low oxygen levels as a result of enrichment with nitrogen and
phosphorus. We found markedly higher temperature sensitivity of bacterioplankton in coastal environments with high
concentrations of DOC. Thus, climate-related factors (i.e.,
temperature and runoff) can influence hypoxia in estuarine
waters, and in such cases reduction of nitrogen and phosphorus alone may not be an effective restoration measure.
Climate-induced changes in geochemical and biological
conditions will alter the concentration and distribution of
semi-persistent and persistent organic pollutants in the sea.
The net effect is expected to differ among pollutants depending on their lipophilicity, sorption properties, volatility, and resistance to metabolism. This is important to
consider when forecasting food web transfer and human
exposure and when designing or modifying monitoring
programs for such pollutants (Undeman et al. 2015).
It has been suggested that, because the invasive deepburrowing polychaete Marenzelleria stimulates the release
of legacy pollutants from fiber banks and other hotspots in
the Gulf of Bothnia (Josefsson et al. 2010, 2011), it may
have played a part in a recent local reproduction failure in
white-tailed eagle (Haliaeetus albicilla) (Helander and
Bignert 2012). Although the interactions between native
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food webs, invasive species, pollutant chemistry, and climate change are complex, they clearly need to be considered when managing marine ecosystem.
While a number of management plans have been developed in response to eutrophication (e.g., the HELCOM
Baltic Sea Action Plan, http://helcom.fi/baltic-sea-actionplan and the EU water framework directive), monitoring
needs to be expanded also to cover secondary producers
and other processes and to encompass changes in climate
and anthropogenic pollutant loads.
Acknowledgments This study was financed by the Strategic Marine
Environmental Research programs Ecosystem dynamics in the Baltic
Sea in a changing climate perspective (ECOCHANGE) and Baltic
Ecosystem Adaptive Management (BEAM). We thank Umeå Marine
Science Centre and the Marine Laboratory in Kalmar for excellent
support during field sampling.
Open Access This article is distributed under the terms of the
Creative Commons Attribution 4.0 International License (http://
creativecommons.org/licenses/by/4.0/), which permits unrestricted
use, distribution, and reproduction in any medium, provided you give
appropriate credit to the original author(s) and the source, provide a
link to the Creative Commons license, and indicate if changes were
made.
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AUTHOR BIOGRAPHIES
Agneta Andersson (&) is a professor in Pelagic Ecology. Her research focuses on the regulation of productivity in marine systems
and ecosystem dynamics in the Baltic Sea in a climate change perspective.
Address: Department of Ecology and Environmental Science, Umeå
University, 901 87 Umeå, Sweden.
e-mail: [email protected]
Ó The Author(s) 2015. This article is published with open access at Springerlink.com
www.kva.se/en
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AMBIO 2015, 44(Suppl. 3):S345–S356
H. E. Markus Meier is an adjunct professor at Stockholm University
and head of the Oceanographic Research Unit at the Swedish Meteorological and Hydrological Institute (SMHI). His current research
interests focus on the analysis of climate variability and the impact of
climate change on the physics and biogeochemical cycles in the
Baltic Sea, North Sea, and Arctic Ocean.
Address: Swedish Meteorological and Hydrological Institute, 601 76
Norrköping, Sweden.
e-mail: [email protected]
Matyas Ripszam is a PhD student in Chemistry and his research
focuses on method development of analyses of environmental pollutants and understanding their distribution in marine environments.
Address: Department of Occupational Medicine, Umeå University,
901 87 Umeå, Sweden.
e-mail: [email protected]
Owen Rowe is an ecologist and environmental microbiologist. His
research interests include ecosystem balancing and function, and
microbial processes in a variety of natural and polluted environments.
Address: Department of Ecology and Environmental Science, Umeå
University, 901 87 Umeå, Sweden.
e-mail: [email protected]
Johan Wikner is an associate professor in marine microbiology and a
manager of Umeå Marine Sciences Centre. His research is focused on
bacterial growth and respiration in marine systems, related to Land–
Sea interaction, pollution, and climate change.
Address: Umeå Marine Science Centre, Umeå University, 905 71
Hörnefors, Sweden.
e-mail: [email protected]
Peter Haglund is a professor in Chemistry. His specialties include
method development for qualitative and quantitative analysis of environmental pollutants and their application in environmental sciences.
Address: Department of Chemistry, Umeå University, 901 87 Umeå,
Sweden.
e-mail: [email protected]
Kari Eilola is a senior scientist and marine environmental research
leader at the oceanographic research unit at the Swedish Meteorological and Hydrological Institute (SMHI). His research interests include physical and biogeochemical modeling of the Baltic Sea.
123
Address: Swedish Meteorological and Hydrological Institute, 426 71
Västra Frölunda, Sweden.
e-mail: [email protected]
Catherine Legrand is a professor of Marine Ecology. Her research
focuses on microbial interactions, plankton ecology, and microalgae
applications.
Address: Centre for Ecology and Evolution in Microbial model
Systems - EEMiS, Linnaeus University, 391 82 Kalmar, Sweden.
e-mail: [email protected]
Daniela Figueroa is a PhD student in ecology focusing her studies on
bacterial communities and microbial food webs.
Address: Department of Ecology and Environmental Science, Umeå
University, 901 87 Umeå, Sweden.
e-mail: [email protected]
Joanna Paczkowska is a PhD student in ecology focusing her studies
on phytoplankton ecology.
Address: Department of Ecology and Environmental Science, Umeå
University, 901 87 Umeå, Sweden.
e-mail: [email protected]
Elin Lindehoff holds a PhD in Aquatic Ecology. Her research deals
with plankton ecology, algal solutions, and water quality management.
Address: Centre for Ecology and Evolution in Microbial model
Systems - EEMiS, Linnaeus University, 391 82 Kalmar, Sweden.
e-mail: [email protected]
Mats Tysklind is a professor in Environmental Chemistry. His research focuses on transport and fate of organic pollutants in aquatic
and terrestrial environments.
Address: Department of Chemistry, Umeå University, 901 87 Umeå,
Sweden.
e-mail: [email protected]
Ragnar Elmgren is emeritus professor of Brackish Water Ecology
and has studied Baltic Sea ecosystems, benthos, eutrophication,
cyanobacterial blooms, and management since 1970.
Address: Department of Ecology, Environment and Plant Sciences,
Stockholm University, 106 91 Stockholm, Sweden.
e-mail: [email protected]
Ó The Author(s) 2015. This article is published with open access at Springerlink.com
www.kva.se/en
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