Projected future climate change and Baltic Sea ecosystem management

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.Electronic supplementary materialThe online version of this article (doi:10.1007/s13280-015-0654-8) contains supplementary material, which is available to authorized users.

Fatty acid composition and lipid content in the copepod Limnocalanus macrurus during summer in the southern Bothnian Sea

“…Instead, freshening of the water has likely brought about an increase of its biomass in the Bothnian Sea and the Bothnian Bay since 1990 [16]. Projections for the future development of the Baltic Sea suggest a further decline of salinity [17,18], which may cause species that originate from a high-salinity environment to disappear and freshwater and glacial relict species, such as L. macrurus, to increase in numbers [18]. However, with consequent rising temperatures, the propagation of L. macrurus requires that the population is able to reproduce and grow in its distributional areas.…”

The Effect of Increased Loads of Dissolved Organic Matter on Estuarine Microbial Community Composition and Function

“…The consequences of climate change are therefore expected to vary regionally (Rönnberg and Bonsdorff, 2004). The north receives large inputs of riverine DOM rich in humic substances (Andersson et al, 2015), while the south receives a comparatively nutrient rich riverine DOM inflow (Stepanauskas et al, 2002). The riverine loadings differ significantly in C:N:P stoichiometry depending on region and can potentially have very different effects on the recipient ecosystem.…”

Biodiversity and ecosystem services in Nordic coastal ecosystems

“…Climate-related pressures include melting sea ice, decreased snow cover and permafrost thawing and increased discharges of organic matter, which may lead to altered trophic relationships (e.g. Andersson et al 2015). Even in a scenario wherere CO2 levels have been stabilised at 450 PPM, dramatic consequences can still be expected in the Nordic region (Fig.…”