| 1. |
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Biological Oceanography of the Baltic Sea
- 2017
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Samlingsverk (redaktörskap) (refereegranskat)abstract
- This is the first comprehensive science-based textbook on the biology and ecology of the Baltic Sea, one of the world’s largest brackish water bodies. The aim of this book is to provide students and other readers with knowledge about the conditions for life in brackish water, the functioning of the Baltic Sea ecosystem and its environmental problems and management. It highlights biological variation along the unique environmental gradients of the brackish Baltic Sea Area (the Baltic Sea, Belt Sea and Kattegat), especially those in salinity and climate.The first part of the book presents the challenges for life processes and ecosystem dynamics that result from the Baltic Sea’s highly variable recent geological history and geographical isolation. The second part explains interactions between organisms and their environment, including biogeochemical cycles, patterns of biodiversity, genetic diversity and evolution, biological invasions and physiological adaptations. In the third part, the subsystems of the Baltic Sea ecosystem – the pelagic zone, the sea ice, the deep soft sea beds, the phytobenthic zone, the sandy coasts, and estuaries and coastal lagoons – are treated in detail with respect to the structure and function of communities and habitats and consequences of natural and anthropogenic constraints, such as climate change, discharges of nutrients and hazardous substances. Finally, the fourth part of the book discusses monitoring and ecosystem-based management to deal with contemporary and emerging threats to the ecosystem’s health.
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| 2. |
- Bradshaw, Clare, et al.
(författare)
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Joint effects of gamma radiation and cadmium on subcellular-, individual-and population-level endpoints of the green microalga Raphidocelis subcapitata
- 2019
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Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X .- 1879-1514. ; 211, s. 217-226
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Tidskriftsartikel (refereegranskat)abstract
- Interpreting and predicting the combined effects of toxicants in the environment is an important challenge in ecotoxicology. How such effects are connected across different levels of biological organisation is an additional matter of uncertainty. Such knowledge gaps are particularly prominent with regards to how ionising radiation interacts with contaminants. We assessed the response of twelve endpoints at the subcellular, individual and population level in a green microalga when exposed singly and jointly to gamma radiation and cadmium (Cd). We used a fully factorial experimental design where observed effects were compared to those predicted by the Independent Action (IA) model for mixture toxicity to determine whether they deviated from additivity. Subcellular endpoints (e.g., catalase, thiamine diphosphate, xanthophyll cycle pigments) showed an increased antioxidant and/or photoprotective response. However, our results indicate that this protection was not sufficient to prevent lipid peroxidation, which also increased with dose. At ecologically relevant doses, most interactions between gamma radiation and Cd regarding subcellular-, individual- and population-level endpoints were additive as predicted by the IA model. However, exposure to binary mixtures displayed antagonistic interactions between gamma radiation and Cd at the higher end of the tested dose spectrum. No correlations were observed between subcellular endpoints and higher-level endpoints, but there were linkages between individual and population endpoints. Our results suggest that antagonistic interactions between gamma radiation and Cd can occur at higher doses and that these interactions seem to disseminate from subcellular and individual to population level. Possible consequences for aquatic primary production and food-web interactions are discussed.
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| 3. |
- Chamberlain, E. J., et al.
(författare)
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Impacts of sea ice melting procedures on measurements of microbial community structure
- 2022
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Ingår i: Elementa. - : University of California Press. - 2325-1026. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Microorganisms play critical roles in sea ice biogeochemical processes. However, microbes living within sea ice can be challenging to sample for scientific study. Because most techniques for microbial analysis are optimized for liquid samples, sea ice samples are typically melted first, often applying a buffering method to mitigate osmotic lysis. Here, we tested commonly used melting procedures on three different ice horizons of springtime, first year, land-fast Arctic sea ice to investigate potential methodological impacts on resulting measurements of cell abundance, photophysiology, and microbial community structure as determined by 16S and 18S rRNA gene amplicon sequencing. Specifically, we compared two buffering methods using NaCl solutions (“seawater,” melting the ice in an equal volume of 35-ppt solution, and “isohaline,” melting with a small volume of 250-ppt solution calculated to yield meltwater at estimated in situ brine salinity) to direct ice melting (no buffer addition) on both mechanically “shaved” and “non-shaved” samples. Shaving the ice shortened the melting process, with no significant impacts on the resulting measurements. The seawater buffer was best at minimizing cell lysis for this ice type, retaining the highest number of cells and chlorophyll a concentration. Comparative measurements of bacterial (16S) community structure highlighted ecologically relevant subsets of the community that were significantly more abundant in the buffered samples. The results for eukaryotic (18S) community structure were less conclusive. Taken together, our results suggest that an equivalent-volume seawater-salinity buffered melt is best at minimizing cell loss due to osmotic stress for springtime Arctic sea ice, but that either buffer will reduce bias in community composition when compared to direct melting. Overall, these findings indicate potential methodological biases that should be considered before developing a sea ice melting protocol for microbiological studies and afterwards, when interpreting biogeochemical or ecological meaning of the results.
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| 4. |
- Diez, Beatriz, et al.
(författare)
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High cyanobacterial nifh gene diversity in arctic seawater and sea ice brine
- 2012
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Ingår i: Environmental Microbiology Reports. - : Wiley. - 1758-2229. ; 4:3, s. 360-366
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Tidskriftsartikel (refereegranskat)abstract
- Although cyanobacterial diazotrophs are common in Arctic terrestrial and freshwater habitats, they have been assumed to be absent from Arctic marine habitats. We report here a high diversity of cyanobacterial nifH genes in Fram Strait and the Greenland Sea. The nifH gene encodes the iron protein of the nitrogenase enzyme complex, which is essential for biological N2 fixation. Using primers specific for nifH genes we uncovered communities of autotrophic and heterotrophic bacteria in sea ice brine and seawater between latitudes 65 and 81 degrees N. Cyanobacteria (Oscillatoriales and Chroococcales) with known marine planktonic and benthic distributions were distinguished, alongside a mix of metabolically versatile eubacteria (nifH Clusters I and III). Using primers selective for cyanobacterial nifH genes we identified filamentous non-heterocystous Trichodesmium-like and LPP (Leptolyngbya, Phormidium and Plectonema)-like Oscillatoriales, as well as Cyanothece-like Chroococcales in a brine sample from 81 degrees N. The occurrence of Trichodesmium-like cyanobacteria was further confirmed by sequences of the hetR gene of Trichodesmium. Microscopic examinations confirmed the presence of viable filamentous and unicellular cyanobacteria. Our results reveal the potential for microbial N2 fixation in the Arctic seas. However, it is still left to determine if these genes are also metabolically active before any biogeochemical importance of diazotrophy in the polar oceans can be assessed.
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| 5. |
- Diez, Beatriz, et al.
(författare)
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Water nutrient stoichiometry modifies the nutritional quality of phytoplankton and somatic growth of crustacean mesozooplankton
- 2013
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Ingår i: Marine Ecology Progress Series. - : Inter-Research Science Center. - 0171-8630 .- 1616-1599. ; 489, s. 93-
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Tidskriftsartikel (refereegranskat)abstract
- Here, we investigated how changes in water nutrient stoichiometry may change the nutritional quality of phytoplankton for mesozooplankton. For 6 d, we added nutrients to nine 1300 l mesocosms with natural summer phytoplankton from the Baltic Sea to create communities that were N-limited (P-treatment), Si-limited (PN-treatment) and not limited by nutients (PNSi-treatment). With the addition of P, no major changes occurred in phytoplankton biomass or species composition with time. With the addition of P and N, with or without excess of Si, C: N ratios approached the Redfield ratio, biomass increased and diatoms and dinoflagellates became dominant. Analysis of the 18S rRNA gene showed that the availability and diversity of phytoplankton other than diatoms and dinoflagellates, like prasinophytes or heterotrophic flagellates and ciliates, were not affected by the nutrient treatments. We then tested how the modified phytoplankton communities affected somatic growth in a natural mesozooplankton community dominated by the copepod genus Acartia. After 6 d of grazing, the zooplankton more than doubled their C content per individual when grazing on the Si-limited phytoplankton (PN-treatment) while total community biomass was maintained. In the other 2 treatments, the C content per individual remained the same and total community biomass decreased by ca. 60%, which suggests that the zooplankton was not optimally fed. Thus, a phytoplankton community with stoichiometry close to the Redfield ratio provided the best nutritional quality for the zooplankton, but not when the diatoms were Si saturated. This study shows that nutrient stoichiometry in the seawater can affect zooplankton growth by modification of the phytoplankton community. It also shows that the food quality of phytoplankton does not depend only on the taxonomic composition, but also on the nutrient stoichiometry.
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| 6. |
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| 7. |
- Fernández-Gómez, Beatriz, et al.
(författare)
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Bacterial community structure in a sympagic habitat expanding with global warming : brackish ice brine at 85-90 degrees N
- 2019
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Ingår i: The ISME Journal. - : Springer Science and Business Media LLC. - 1751-7362 .- 1751-7370. ; 13:2, s. 316-333
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Tidskriftsartikel (refereegranskat)abstract
- Larger volumes of sea ice have been thawing in the Central Arctic Ocean (CAO) during the last decades than during the past 800,000 years. Brackish brine (fed by meltwater inside the ice) is an expanding sympagic habitat in summer all over the CAO. We report for the first time the structure of bacterial communities in this brine. They are composed of psychrophilic extremophiles, many of them related to phylotypes known from Arctic and Antarctic regions. Community structure displayed strong habitat segregation between brackish ice brine (IB; salinity 2.4-9.6) and immediate sub-ice seawater (SW; salinity 33.3-34.9), expressed at all taxonomic levels (class to genus), by dominant phylotypes as well as by the rare biosphere, and with specialists dominating IB and generalists SW. The dominant phylotypes in IB were related to Candidatus Aquiluna and Flavobacterium, those in SW to Balneatrix and ZD0405, and those shared between the habitats to Halomonas, Polaribacter and Shewanella. A meta-analysis for the oligotrophic CAO showed a pattern with Flavobacteriia dominating in melt ponds, Flavobacteriia and Gammaproteobacteria in solid ice cores, Flavobacteriia, Gamma- and Betaproteobacteria, and Actinobacteria in brine, and Alphaproteobacteria in SW. Based on our results, we expect that the roles of Actinobacteria and Betaproteobacteria in the CAO will increase with global warming owing to the increased production of meltwater in summer. IB contained three times more phylotypes than SW and may act as an insurance reservoir for bacterial diversity that can act as a recruitment base when environmental conditions change.
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| 8. |
- Haubner, Norbert, et al.
(författare)
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ABIOTIC STRESS MODIFIES THE SYNTHESIS OF ALPHA-TOCOPHEROL AND BETA-CAROTENE IN PHYTOPLANKTON SPECIES
- 2014
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Ingår i: Journal of Phycology. - : Wiley. - 0022-3646 .- 1529-8817. ; 50:4, s. 753-759
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Tidskriftsartikel (refereegranskat)abstract
- We performed laboratory experiments to investi-gate whether the synthesis of the antioxidants -tocopherol (vitamin E) and -carotene in phytoplankton depends on changes in abiotic factors. Cultures of Nodularia spumigena, Phaeodactylum tricornutum, Skeletonema costatum, Dunaliella tertiolecta, Prorocentrum cordatum, and Rhodomonas salina were incubated at different tempe-ratures, photon flux densities and salinities for 48h. We found that abiotic stress, within natural ecological ranges, affects the synthesis of the two antioxidants in different ways in different species. In most cases antioxidant production was stimulated by increased abiotic stress. In P.tricornutumKAC 37 and D.tertiolectaSCCAP K-0591, both good producers of this compound, -tocopherol accumulation was negatively affected by environmentally induced higher photosystem II efficiency (F-v/F-m). On the other hand, -carotene accumulation was positively affected by higher F-v/F-m in N.spumigena KAC 7, P.tricornutum KAC 37, D.tertiolecta SCCAP K-0591 and R.salina SCCAP K-0294. These different patterns in the synthesis of the two compounds may be explained by their different locations and functions in the cell. While -tocopherol is heavily involved in the protection of prevention of lipid peroxidation in membranes, -carotene performs immediate photo-oxidative protection in the antennae complex of photosystem II. Overall, our results suggest a high variability in the antioxidant pool of natural aquatic ecosystems, which can be subject to short-term temperature, photon flux density and salinity fluctuations. The antioxidant levels in natural phytoplankton communities depend on species composition, the physiological condition of the species, and their respective strategies to deal with reactive oxygen species. Since -tocopherol and -carotene, as well as many other nonenzymatic antioxidants, are exclusively produced by photo-synthetic organisms, and are required by higher trophic levels through dietary intake, regime shifts in the phytoplankton as a result of large-scale environmental changes, such as climate change, may have serious consequences for aquatic food webs.
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| 9. |
- Hillebrand, Helmut, et al.
(författare)
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Warming leads to higher species turnover in a coastal ecosystem
- 2010
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 16:4, s. 1181-1193
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Tidskriftsartikel (refereegranskat)abstract
- The responses of ecological communities and ecosystems to increased rates of environmental change will be strongly influenced by variation in the diversity of community composition. Yet, our understanding of how diversity is affected by rising temperatures is inconclusive and mainly based on indirect evidence or short-term experiments. In our study, we analyse the diversity and species turnover of benthic epilithic communities within the thermal flume of a nuclear power plant at the Swedish coast. This flume covers the range of predicted future temperature rises. Species composition was significantly different between control sites and sites with higher temperatures. We found that temperature had little effect on the number of species in three functional groups (macroinvertebrates, benthic diatoms, and macrophytes, which here comprise multicellular algae and macroscopic colonies of unicellular algae and cyanobacteria), neither at single sampling dates nor summed for the entire observation year. However, species turnover significantly increased with increasing temperature for diatoms, macrophytes and invertebrates. Different temperature regimes resulted in significantly different species composition and indicator species. Thus, increasing temperatures in the thermal flume increased temporal beta-diversity and decreased compositional stability of communities, although observed richness did not change at any point in time. We highlight the need to investigate the consequences of such declines in compositional stability for functional stability of ecosystem processes.
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| 10. |
- Hylander, Samuel, et al.
(författare)
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Concentrations of sunscreens and antioxidant pigments in Arctic Calanus spp. in relation to ice cover, ultraviolet radiation, and the phytoplankton spring bloom
- 2015
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Ingår i: Limnology and Oceanography. - : Wiley. - 0024-3590 .- 1939-5590. ; 60, s. 2197-2206
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Tidskriftsartikel (refereegranskat)abstract
- Arctic zooplankton ascend to shallow depths during spring to graze on the yearly occurring phytoplankton bloom. However, in surface waters they are exposed to detrimental ultraviolet radiation (UVR) levels. Here, we quantified concentrations of substances known to have UVR-protective functions, namely mycosporine-like amino acids (MAAs) and the carotenoid astaxanthin, from March to May in Calanus finmarchicus, Calanus glacialis and Calanus hyperboreus. Ice cover was 100% in the beginning of March, started to break up during April and was gone by the end of May. UVR-exposure in the water column was tightly linked to the ice conditions and water UVR-transparency was up to 6 m (depth where 1% radiation remains). Concentrations of MAAs in C. finmarchicus and C. glacialis increased sharply during ice break-up and peaked concurrently with maximum chlorophyll a (Chl a) levels. MAA-concentrations in C. hyperboreus increased later in accordance with its later arrival to the surface. The concentration of astaxanthin increased in all three species over time but there was no synchrony with ice conditions or the phytoplankton bloom. Even though only the upper 6 m of the water column was affected by UV-radiation, MAAs in the copepods were tightly correlated to the UV-threat. Hence, changes in ice cover are projected to have a large impact on the UVR-exposure of zooplankton emphasizing the importance of the timing of zooplankton ascent from deep waters in relation to the phytoplankton bloom and the ice break-up.
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| 11. |
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| 12. |
- Kautsky, Hans, et al.
(författare)
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The phytobenthic zone
- 2017
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Ingår i: Biological Oceanography of the Baltic Sea. - Dordrecht : Springer. - 9789400706675 - 9789400706682 ; , s. 387-455
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Bokkapitel (refereegranskat)abstract
- 1. Phytobenthic communities consist of macrophytes (macroalgae, vascular plants andmosses) with their accompanying fauna and microorganisms.2. The phytobenthic communities occur in the photic zone, which in the Baltic Sea extendsfrom the water surface down to a*20 m water depth, but in turbid coastal waters onlydown to*5m.3. The type of vegetation is determined by the available substrate, which is a result ofgeography and geology in combination with currents. Most macroalgae grow attachedto hard substrates whereas vascular plants and charophytes grow on sandy or soft (siltand mud) substrates.4. Generally, the coastal areas of the Baltic Sea consist of mixed substrates with anintermingled vegetation of vascular plants and algae. In the northern Baltic Sea hardsubstrates dominate in the outer archipelagos, and in the southeastern Baltic Sea sandyand muddy substrates dominate.5. Luxuriant stands of macrophytes provide food, shelter and spawning habitats for theassociated sessile and mobile micro-, meio- and macrofauna, includingfish.6. On an ecosystem-wide scale, the phytobenthic communities vary along the large-scaleBaltic Sea gradient. Biomass decreases with lower salinity and colder climate, while theproportion of freshwater species increases.7. On a local scale, the phytobenthic communities are mainly, directly or indirectly, shapedby water movement (e.g.by the occurrence of sandy beaches and rocky shores) andwinter ice cover. Light and substrate availability give rise to typical depth zonationpatterns, ending with soft-substrate communities deepest down.8. On a small scale (patches), phytobenthic community structure and composition isinfluenced by microhabitat structure and biotic interactions.9. The phytobenthic communities in the brackish Baltic Sea are more sensitive to dis-turbance than their marine counterparts due to low diversity, physiological stress and theloss of sexual reproduction when species approach their salinity limit.
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| 13. |
- Liu, Bin-yang, et al.
(författare)
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Toxic effects of erythromycin, ciprofloxacin and sulfamethoxazole on photosynthetic apparatus in Selenastrum capricornutum
- 2011
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Ingår i: Ecotoxicology and Environmental Safety. - : Elsevier BV. - 0147-6513 .- 1090-2414. ; 74:4, s. 1027-1035
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Tidskriftsartikel (refereegranskat)abstract
- The effects of three antibiotics (erythromycin, ciprofloxacin and sulfamethoxazole) on photosynthesis process of Selenastrum capricornutum were investigated by determining a battery of parameters including photosynthetic rate, chlorophyll fluorescence, Hill reaction, and ribulose-1.5-bisphosphate carboxylase activity, etc. The results indicated that three antibiotics could significantly inhibit the physiological progress including primary photochemistry, electron transport, photophosphorylation and carbon assimilation. Erythromycin could induce acute toxic effects at the concentration of 0.06 mg L(-1) while the same results were exhibited for ciprofloxacin and sulfamethoxazole at higher than 1.0 mg L(-1). Erythromycin was considerably more toxic than ciprofloxacin and sulfamethoxazole and may pose a higher potential risk to the aquatic ecosystem. Some indices like chlorophyll fluorescence, Mg(2+)-ATPase activity and RuBPCase activity showed a high specificity and sensitivity to the exposure of erythromycin, and may be potentially used as candidate biomarkers for the exposure of the macrolide antibiotics.
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| 14. |
- Mock, Thomas, et al.
(författare)
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Multiomics in the central Arctic Ocean for benchmarking biodiversity change
- 2022
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Ingår i: PLoS biology. - : Public Library of Science (PLoS). - 1544-9173 .- 1545-7885. ; 20:10
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Tidskriftsartikel (refereegranskat)abstract
- Multiomics approaches need to be applied in the central Arctic Ocean to benchmark biodiversity change and to identify novel species and their genes. As part of MOSAiC, EcoOmics will therefore be essential for conservation and sustainable bioprospecting in one of the least explored ecosystems on Earth.
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| 15. |
- Nie, Xiang-Ping, et al.
(författare)
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Why Baltic herring and sprat are weak conduits for astaxanthin from zooplankton to piscivorous fish
- 2011
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Ingår i: Limnology and Oceanography. - : Wiley. - 0024-3590 .- 1939-5590. ; 56:3, s. 1155-1167
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Tidskriftsartikel (refereegranskat)abstract
- Atlantic salmon living in the brackish Baltic Sea have lower muscle pigmentation than populations elsewhere. The pigment in question is the antioxidant and vitamin A precursor astaxanthin, which is synthesized by crustaceans from algal carotenoids. Baltic salmon feed nearly exclusively on the clupeids sprat and herring. To evaluate astaxanthin availability to salmon we assessed astaxanthin levels and isomeric composition in their prey fish. We also analyzed astaxanthin dynamics in the dominant piscivorous fish in the Baltic Sea, the Atlantic cod. The geometrical E-(trans-) and Z-(cis-) isomers were distributed selectively in fish tissues, with highest E : Z ratios in salmon gonads (82 : 18) and lowest in herring gonads (24 : 76). Sprat and herring are not ideal prey with respect to their high whole-body concentrations of Z-isomers, which have low bioavailability for salmon and cod. These Z-isomers predominantly accumulate in the clupeid gonads. A crucial mechanism for the transport of astaxanthin from clupeids to piscivores is the direct transfer of crustacean astaxanthin (mainly all-E) from the clupeid stomachs. Low stomach astaxanthin content in clupeids decreases total astaxanthin transfer to higher trophic levels. In autumn, herring stomachs (including contents) had 12.5 times lower astaxanthin concentrations than sprat stomachs, and herring had 2.8 times less whole-body all-E-astaxanthin (by weight) than sprat. These results confirm recent reports of starvation in the Baltic herring, which may further decrease astaxanthin levels in the Baltic salmon. Cod did not have lower astaxanthin levels than their Atlantic counterpart, which may be attributed to their lower need for astaxanthin and higher food diversity.
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| 16. |
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Scientific considerations of how Arctic Marine Protected Area (MPA) networks may reduce negative effects of climate change and ocean acidification : Report from the Third Expert Workshop on Marine Protected Area networks in the Arctic, organised by Sweden and Finland under the auspices of the PAME working group of the Arctic Council in Helsinki, Finland, 21-22 September 2017
- 2017
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Rapid environmental changes in the ArcticDuring the last two decades, the Arctic region has become an area of international strategic importance for states, businesses, NGOs and other stakeholders. The rapid environmental changes in the Arctic create new opportunities for different actors that may impact negatively on ecological and social values. Global climate change and ocean acidification change the habitats of the cold-adapted organisms living in the Arctic, with the risk of exterminating unique biodiversity. Human-induced emissions of greenhouse gases (primarily carbon dioxide, methane and nitrous oxide) affect the balance between energy entering and leaving the Earth’s system resulting in global warming, melting of sea-ice (which increases heat absorption by the Arctic Ocean), and associated climate change. Approximately 27 % of the carbon dioxide released to the atmosphere every year is absorbed by the oceans. This keeps the atmosphere from warming as much as it otherwise would, but creates ocean acidification. In the Arctic region climate change and ocean acidification take place 10-100 times faster than at any time in the last 65 million years.Intention of the workshopThis third expert workshop on Marine Protected Area (MPA) networks in the Arctic, organised by Sweden and Finland, was held in Helsinki (Finland) and its outcome is a contribution to the ‘‘PAME MPA-network toolbox’’ project. An MPA, as defined by PAME, is ‘‘a clearly defined geographical space recognized, dedicated, and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values’. An MPA network is a collection of individual MPAs or reserves operating cooperatively and synergistically, at various spatial scales, and with a range of protection levels that are designed to meet objectives that a single reserve cannot achieve. During this third expert workshop the scientific basis of how MPA networks may reduce negative effects of climate change and ocean acidification in the Arctic region was discussed. Workshop participants were mainly scientists with expertise on Arctic marine ecosystems, climate change, ocean acidification and/or MPAs. The intention of the workshop was not to reach consensus and provide a fixed list of recommendations, but rather to summarize: (1) the best available knowledge that can already be applied to the planning of a pan-Arctic MPA network, and (2) the primary uncertainties and, hence, what necessary scientific knowledge is still lacking. As such, the six main outcomes from the workshop below contribute to the scientific basis for the potential of MPAs as a tool to meet the threats posed by climate change and ocean acidification to Arctic ecosystems and livelihoods.A paradigm shift for establishing MPAs is necessaryGiven the rapid environmental changes and unprecedented rate of loss of Arctic sea ice there is an urgency to protect habitats that are essential for ecosystem functioning and to link MPAs in an international network. Humanity has now the opportunity of a pro-active and precautionary approach vis-à-vis the largely intact, highly sensitive and unique cold-adapted Arctic marine ecosystems. The current paradigm for the creation of MPAs seems to be that a direct regional or local threat needs to be proven before an MPA can be designated. However, climate change and ocean acidification are global processes that operate across the whole Arctic, and therefore this paradigm should be shifted towards one that establishes MPA networks to protect what is valued and cherished before it is harmed. This calls for applying the precautionary principle and creating Arctic MPA networks that will support resilience of biodiversity and ecosystem services to climate change and ocean acidification. Scientists are aware that not all desired knowledge for planning such networks is available at this time. This includes uncertainty associated with projecting the consequences of climate change across the physical (e.g. climate models), ecological (e.g. species diversity, ecosystem processes) to the human domain (e.g. ecosystem services, human well-being). Uncertainty about the effects of climate change and ocean acidification grows when moving from physical processes to ecology and finally to human well-being. Nonetheless, general ecological principles and additional experience from other regions (e.g. Antarctica, Baltic Sea) provide sufficient basic understanding to start designing a robust pan-Arctic MPA network already now and to develop and implement the necessary connected management measures.Existing MPA criteria need to be adapted to Arctic conditionsCreating an MPA network for the Arctic will require adaptation of established criteria to the unique, and rapidly changing, character of the region. For example, optimal MPA locations for some MPAs in the Arctic Ocean may not be stationary in space and time; e.g. high-biodiversity marginal ice zone (MIZ) ecosystems will become more dynamic in time and space, contracting in winter and expanding in summer, with climate change. In order to account for the migration of species with moving physico-chemical conditions (so-called ‘climate tracking’) creating dynamic MPAs along oceanographic and climatic gradients may be a feasible and effective approach. Such focus on ocean features, the integration of other effective area-based measures next to MPAs, as well as the systematic integration of traditional and local knowledge (TLK), will be essential in the process of designating MPA networks. In so doing, the vulnerability and status of Arctic ecosystems to cumulative drivers and pressures from not only regional and local scales (fishing, tourism, pollution, etc.) but also global scales (climate change and ocean acidification) should be monitored and reviewed on a regular basis.Arctic MPAs should be located in areas that are expected to become refugiaClimate change and ocean acidificationdo not operate in isolation but combine with regional and local environmental stressors to affect Arctic species, habitats, and ecosystems. It is possible to lessen the total stress burden and increase the resilience of biodiversity to the impacts of climate change and ocean acidification by mitigating stresses from direct anthropogenic pressures, such as habitat destruction, fishing, shipping, discharges of hazardous substances, etc., through establishing MPA networks. This will not ‘solve’ the underlying problems of climate change and ocean acidification, which can only be done by reducing atmospheric greenhouse gas emissions, but it will ‘buy time’ during which the underlying problems are addressed globally.Additional stresses should be targetedA key aspect is how to identify the location of prospective MPAs within a network. Since the effects of climate change and ocean acidification are unevenly distributed across the Arctic Ocean, it would be recommended to protect habitats that will act as refugia for Arctic biodiversity. For example, protecting the areas north of Greenland, where summer sea ice is projected to be most long-lasting, or parts of the Arctic Ocean where the supply of organic matter through permafrost melt, glacier melt, higher precipitation and higher river runoff (with increasing coastal CO2 concentrations through microbial activity) will be lowest. The 18 Arctic large marine ecosystems (LMEs) reflect the marine ecosystem variability in the region, and should be used to draft plans for MPA networks to more effectively consider representativeness.The scientific knowledge basis must be improvedThe workshop highlighted the need for a dedicated group to compile relevant geophysical and biological data for the purpose of MPA network planning. These data should include the changing environment, ‘spatial adaptation planning’, biochemical gradients, and identification of areas of high and low impact of climate change and ocean acidification. There is a wealth of information available (both reviews and analyses of knowledge gaps from CAFF, AMAP and others), that can be used for MPA planning but this information is highly scattered and needs to be collated and made spatially explicit, when possible. While the planning for MPA networks can start already now, there remains a large need for monitoring and relevant scientific research. This would require not only improved scientific cooperation between countries but also truly integrated international monitoring and research to decrease fragmentation and duplication of research.Identification of research prioritiesGaps in knowledge identified by the workshop participants mainly concern the winter season, the vulnerability and resilience of the Arctic marine ecosystems and the need to support sustainable development. With respect to climate change much more is known about species higher up in the food web (seabirds, marine mammals, some fish) than about species lower in food web. For ocean acidification, most of the experimental work has been done on lower trophic levels. Much uncertainty surrounds the fate of Arctic ecosystems in a future world and how to deal with uncertainties is an issue that should be addressed in scientific studies. For example, the disappearance of strongly ice-associated species in many places will likely lead to a state-change in the associated ecosystem, yet the timing and nature of that change is currently unpredictable. While the basic drivers of the Arctic shelf-sea ecosystems are quite well understood, there is a massive lack of information at all trophic levels for the Central Arctic Ocean LME, i.e. the deep central basin, and key species are difficult to identify. Presently, this high-latitude ecosystem is ice-bound, but climate projections indicate that it will become ice-free during summer within decades; the projected spatial and temporal variability is however very large and i
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| 17. |
- Skjoldal, Hein Rune, et al.
(författare)
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Fish
- 2022
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Ingår i: Ecosystem Assessment of the Central Arctic Ocean. - Brussels : International Council for the Exploration of the Sea. - 9788774829737 ; , s. 129-130
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Bokkapitel (refereegranskat)
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| 18. |
- Snoeijs-Leijonmalm, Pauline, et al.
(författare)
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A deep scattering layer under the North Pole pack ice
- 2021
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Ingår i: Progress in Oceanography. - : Elsevier BV. - 0079-6611 .- 1873-4472. ; 194
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Tidskriftsartikel (refereegranskat)abstract
- The 3.3 million km marine ecosystem around the North Pole, defined as the Central Arctic Ocean (CAO), is a blind spot on the map of the world's fish stocks. The CAO essentially comprises the permanently ice-covered deep basins and ridges outside the continental shelves, and is only accessible by ice-breakers. Traditional trawling for assessing fish stocks is impossible under the thick pack ice, and coherent hydroacoustic surveys are unachievable due to ice-breaking noise. Consequently, nothing is known about the existence of any pelagic fish stocks in the CAO, although juveniles of Boreogadus saida richly occur at the surface associated with the sea ice and ice-associated Arctogadus glacialis has been reported as well. We here present a first indication of a possible mesopelagic fish stock in the CAO. We had the opportunity to analyse a geophysical hydroacoustic data set with 13 time windows of usable acoustic data over a transect from 84.4 °N in the Nansen Basin, across the North Pole (90.0 °N), to 82.4 °N in the Canada Basin. We discovered a deep scattering layer (DSL), suggesting the presence of zooplankton and fish, at 300–600 m of depth in the Atlantic water layer of the CAO. Maximum possible fish abundance and biomass was very low; values of ca. 2,000 individuals km and ca. 50 kg km were calculated for the DSL in the North-Pole area according to a model assuming that all acoustic backscatter represents 15-cm long B. saida and/or A. glacialis. The true abundance and biomass of fish is even lower than this, but cannot be quantified from this dataset due to possible backscatter originating from pneumatophores of physonect siphonophores that are known to occur in the area. Further studies on the DSL of the CAO should include sampling and identification of the backscattering organisms. From our study we can conclude that if the central Arctic DSL contains fish, their biomass is currently too low for any sustainable fishery.
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| 19. |
- Snoeijs-Leijonmalm, Pauline, 1956-, et al.
(författare)
-
Ecosystem mapping in the central Arctic Ocean (CAO) during the MOSAiC expedition : Final Report
- 2021
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- As a result of global warming, the marine ecosystem around the North Pole, the Central Arctic Ocean (CAO), is in fast transition from a permanently to a seasonally ice-covered ocean. The sea-ice loss will enable summer access to the CAO for non-icebreaking ships, including fishery vessels, in the near future. However, the lack of knowledge on the CAO ecosystem impedes any assessment of the sustainability of potential future fisheries in the CAO. Taking a precautionary approach, nine countries and the EU established in 2021 the Agreement to Prevent Unregulated High Seas Fisheries in the Central Arctic Ocean, which a.o. includes mapping and monitoring of the CAO ecosystem before any commercial fishery is initiated. To reduce the existing lack of knowledge, the EFICA Consortium participated, together with ca. 250 on-board scientists, in sampling and data collection of ecosystem data during four legs of the international MOSAiC expedition in 2019-2020. This report describes the field work performed by the EFICA scientists using water-column acoustics, deep-sea video recording, and fish and eDNA sampling for targeting zooplankton and fish. Further ecosystem data (physical, chemical and biological) were collected by the EFICA scientists in collaboration with other scientists on-board. Together with this report, a metadata database containing lists of all collected samples and data that are relevant for future fishery assessment studies was delivered to the European Commission.
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| 20. |
- Snoeijs-Leijonmalm, Pauline, 1956-, et al.
(författare)
-
Ecosystem mapping in the Central Arctic Ocean (CAO) during the SAS-Oden expedition : Final report
- 2022
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- As a result of global warming, the marine ecosystem around the North Pole, the Central Arctic Ocean (CAO), is in fast transition from a permanently to a seasonally ice-covered ocean. The sea-ice loss is expected to enable summer access to the CAO for non-icebreaking ships, including fishery vessels, in the near future. However, the lack of knowledge on the CAO ecosystem impedes any assessment of the sustainability of potential future fisheries in the CAO. Taking a precautionary approach, the EU and nine countries in October 2018 signed the Agreement to Prevent Unregulated High Seas Fisheries in the Central Arctic Ocean. This agreement entered into force in June 2021 and a.o. requires the establishment of a joint scientific program to improve the understanding of the CAO ecosystem, including mapping and monitoring. To reduce the existing lack of knowledge, 12 scientists from the EFICA Consortium participated, together with 26 other on-board scientists, in sampling and data collection of ecosystem data during the Swedish SAS-Oden expedition in summer 2021. This report describes the field work performed by the EFICA scientists using water-column acoustics, deep-sea optical observations, and fish, zooplankton, sediment otolith and eDNA sampling for targeting fish, zooplankton and mammals. Further ecosystem data (physical, chemical and biological) were collected by the EFICA scientists in collaboration with other scientists on-board. Together with this report, a metadata database containing lists of all collected samples and data that are relevant for future fish-stock modelling and assessment studies was delivered to the European Commission.
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| 21. |
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| 22. |
- Snoeijs-Leijonmalm, Pauline, 1956-
(författare)
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Patterns of biodiversity
- 2017
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Ingår i: Biological Oceanography of the Baltic Sea. - Dordrecht : Springer. - 9789400706675 - 9789400706682 ; , s. 123-191
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Bokkapitel (refereegranskat)
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| 23. |
- Snoeijs-Leijonmalm, Pauline, 1956-, et al.
(författare)
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Review of the research knowledge and gaps on fish populations, fisheries and linked ecosystems in the Central Arctic Ocean (CAO)
- 2020
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report presents a review of the research knowledge and gaps on fish populations, fisheries and linked ecosystems in the Central Arctic Ocean (CAO). The CAO comprises the deep basins of the Arctic Ocean beyond the shelf break, which largely overlap with the High Seas of the Arctic Ocean, i.e. the marine areas outside the Exclusive Economic Zones (EEZs) of the Arctic coastal nations. The authors of the report are members of the European Fisheries Inventory in the Central Arctic Ocean (EFICA) Consortium. This study was funded by the European Commission as an EU contribution to the international cooperation within the Agreement to Prevent Unregulated High Seas Fisheries in the Central Arctic Ocean.
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| 24. |
- Snoeijs-Leijonmalm, Pauline, 1956-
(författare)
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Sympagic and pelagic bacterial communities
- 2022
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Ingår i: Ecosystem Assessment of the Central Arctic Ocean. - Copenhagen : International Council for the Exploration of the Sea. - 9788774829737 ; , s. 123-125
-
Bokkapitel (refereegranskat)
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| 25. |
- Snoeijs-Leijonmalm, Pauline, 1956-, et al.
(författare)
-
Towards better integration of environmental science in society : Lessons from BONUS, the joint Baltic Sea environmental research and development programme
- 2017
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Ingår i: Environmental Science and Policy. - : Elsevier BV. - 1462-9011 .- 1873-6416. ; 78, s. 193-209
-
Tidskriftsartikel (refereegranskat)abstract
- Integration of environmental science in society is impeded by the large gap between science and policy that is characterised by weaknesses in societal relevance and dissemination of science and its practical implementation in policy. We analyse experiences from BONUS, the policy-driven joint Baltic Sea research and development programme (2007-2020), which is part of the European Research Area (ERA) and involves combined research funding by eight EU member states. The ERA process decreased fragmentation of Baltic Sea science and BONUS funding increased the scientific quality and societal relevance of Baltic Sea science and strengthened the science policy interface. Acknowledging the different drivers for science producers (academic career, need for funding, peer review) and science users (fast results fitting policy windows), and realising, that most scientists aim at building conceptual understanding rather than instrumental use, bridges can be built through strategic planning, coordination and integration. This requires strong programme governance stretching far beyond selecting projects for funding, such as coaching, facilitating the sharing of infrastructure and data and iterative networking within and between science producer and user groups in all programme phases. Instruments of critical importance for successful science-society integration were identified as: (1) coordinating a strategic research agenda with strong inputs from science, policy and management, (2) providing platforms where science and policy can meet, (3) requiring cooperation between scientists to decrease fragmentation, increase quality, clarify uncertainties and increase consensus about environmental problems, (4) encouraging and supporting scientists in disseminating their results through audience-tailored channels, and (5) funding not only primary research but also synthesis projects that evaluate the scientific findings and their practical use in society - in close cooperation with science users - to enhance relevance, credibility and legitimacy of environmental science and expand its practical implementation.
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| 26. |
- Snoeijs-Leijonmalm, Pauline, 1956-, et al.
(författare)
-
Unexpected fish and squid in the central Arctic deep scattering layer
- 2022
-
Ingår i: Science Advances. - : American Association for the Advancement of Science (AAAS). - 2375-2548. ; 8:7
-
Tidskriftsartikel (refereegranskat)abstract
- The retreating ice cover of the Central Arctic Ocean (CAO) fuels speculations on future fisheries. However, very little is known about the existence of harvestable fish stocks in this 3.3 million-square kilometer ecosystem around the North Pole. Crossing the Eurasian Basin, we documented an uninterrupted 3170-kilometer-long deep scattering layer (DSL) with zooplankton and small fish in the Atlantic water layer at 100- to 500-meter depth. Diel vertical migration of this central Arctic DSL was lacking most of the year when daily light variation was absent. Unexpectedly, the DSL also contained low abundances of Atlantic cod, along with lanternfish, armhook squid, and Arctic endemic ice cod. The Atlantic cod originated from Norwegian spawning grounds and had lived in Arctic water temperature for up to 6 years. The potential fish abundance was far below commercially sustainable levels and is expected to remain so because of the low productivity of the CAO.
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| 27. |
- Snoeijs-Leijonmalm, Pauline, 1956-, et al.
(författare)
-
Why is the Baltic Sea so special to live in?
- 2017
-
Ingår i: Biological Oceanography of the Baltic Sea. - Dordrecht : Springer. - 9789400706675 - 9789400706682 ; , s. 23-84
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- "Why is the Baltic Sea so special to live in", is the main question the authors here give several arguments or answers for. Geographical position, geological development, hydrographical features, climate and physical drivers together create the Baltic Sea environment. The Baltic Sea water is brackish and characterized by pronounced salinity gradients, both in horizontal and vertical directions, because of the large volume of freshwater runoff from over 100 rivers, which mixes with the saline water from the Kattegat that enters the Baltic Sea via narrow shallow straits. Being a semi-enclosed continental sea with a large drainage area compared to its water volume , the Baltic Sea ecosystem is heavily impacted by the surrounding landmasses. The water residence time in the Baltic Sea is long (30–40 years), and therefore discharged nutrients and toxic compounds circulate within the sea for a long time, which contributes to its vulnerability to eutrophication and chemical contamination by hazardous substances. The Baltic Sea Area is geologically young and the Baltic Sea ecosystem is extremely young in an evolutionary perspective. Only few macroscopic species are fully adapted to its low-salinity environment. In an ecosystem-wide perspective, the large-scale Baltic Sea gradient is the principal ecological characteristic of the Baltic Sea.
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| 28. |
- Snoeijs, Pauline, et al.
(författare)
-
Astaxanthin dynamics in Baltic Sea mesozooplankton communities
- 2014
-
Ingår i: Journal of Sea Research. - : Elsevier BV. - 1385-1101 .- 1873-1414. ; 85, s. 131-143
-
Tidskriftsartikel (refereegranskat)abstract
- The red pigment astaxanthin is a powerful antioxidant, which occurs in eggs and body tissues of crustaceans and fish. It is produced by crustaceans from algal carotenoids. In a two-year field study we assessed natural concentrations and dynamics of astaxanthin in mesozooplankton communities in the brackish Baltic Sea area. Astaxanthin levels varied between 0.37 and 36 ng L-1. They increased with salinity along the Baltic Sea gradient and were linked to zooplankton biomass and phytoplankton community composition. Astaxanthin concentrations showed typical seasonal patterns and varied from 0.2 to 5.1 ng ind(-1), 0.2 to 3.4 ng (mu g C)(-1) and 6 to 100 ng mm(-3). These concentrations were inversely related to water temperature and strongly linked to zooplankton community composition. Communities dominated by the calanoid copepods Temora longicornis, Pseudocalanus acuspes and Eurytemora spp. generally held the highest concentrations. With increasing cladocerans:copepods biomass ratios community astaxanthin. concentrations decreased and with higher relative biomass of Acartia spp. the proportion of astaxanthin diesters decreased. Diesters prevailed in the cold season and they are thought to improve the antioxidant protection of storage lipids during winter. Climate change causes higher temperature and lower salinity in the Baltic Sea proper. This modifies zooplankton community composition, but not necessarily into a community with lower concentrations of astaxanthin since T. longicornis (high concentrations) has been reported to increase with higher temperature. However, decreased astaxanthin production in the ecosystem is expected if a basin-wide increase in the cladocerans:copepods biomass ratios would occur with further climate change.
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| 29. |
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| 30. |
- Svensson, Filip, 1980-, et al.
(författare)
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Diatom Cell Size, Coloniality and Motility : Trade-Offs between Temperature, Salinity and Nutrient Supply with Climate Change
- 2014
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:10
-
Tidskriftsartikel (refereegranskat)abstract
- Reduction in body size has been proposed as a universal response of organisms, both to warming and to decreased salinity. However, it is still controversial if size reduction is caused by temperature or salinity on their own, or if other factors interfere as well. We used natural benthic diatom communities to explore how body size'' (cells and colonies) and motility change along temperature (2-26 degrees C) and salinity (0.5-7.8) gradients in the brackish Baltic Sea. Fourth-corner analysis confirmed that small cell and colony sizes were associated with high temperature in summer. Average community cell volume decreased linearly with 2.2% per degrees C. However, cells were larger with artificial warming when nutrient concentrations were high in the cold season. Average community cell volume increased by 5.2% per degrees C of artificial warming from 0 to 8.5 degrees C and simultaneously there was a selection for motility, which probably helped to optimize growth rates by trade-offs between nutrient supply and irradiation. Along the Baltic Sea salinity gradient cell size decreased with decreasing salinity, apparently mediated by nutrient stoichiometry. Altogether, our results suggest that climate change in this century may polarize seasonality by creating two new niches, with elevated temperature at high nutrient concentrations in the cold season (increasing cell size) and elevated temperature at low nutrient concentrations in the warm season (decreasing cell size). Higher temperature in summer and lower salinity by increased land-runoff are expected to decrease the average cell size of primary producers, which is likely to affect the transfer of energy to higher trophic levels.
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| 31. |
- Svensson, Filip, 1980-
(författare)
-
Effects of warming on the ecology of algal-dominated phytobenthic communities in the Baltic Sea
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Through climate change, the global average air and surface water temperature has risen 0.85°C during the last 100 years. The Baltic Sea experienced one of the most rapid increase in temperature recorded of marine ecosystems. During the last two decades of the 20th century, the surface water temperature of the Baltic Sea has increased seven times faster than the global average.This thesis is an investigation of how community traits, trophic interactions and ecophysiological processes in the filamentous algal belt in the northern Baltic Sea are affected by warming. The majority of the studies were conducted in or in the vicinity of the Forsmark Biotest basin, an artificial heated enclosure of the southern Bothnian Sea (northern Baltic Sea). One study also included sampling along a natural salinity gradient - the Swedish east coast.In the benthic diatom community, we found that cell size decreases with decreasing seasonal temperature, and increased with warming during the cold season. Warming also selected for motile and colonial traits. Along the salinity gradient, cell size decreased with decreasing salinity, apparently mediated by changes in the nitrogen to phosphorus ratio.In the filamentous algal community, warming increased algal cover and photosynthetic capacity, and affected the ratio of carotene to chlorophyll a ratio. Warming also desensitized the photosynthetic response and growth of algal communities exposed to anthropogenic stressors: increased nitrogen and phosphor concentrations as well as copper additions. In connection to one of the field studies, the first finding of the non-native bivalve Mytilopsis leucophaeata in Sweden was also done.Using a fish exclusion experiment in heated and non-heated areas, we found that warming decreases the number of trophic levels in the lower parts of the food web, which in turn lead to increased top-down control and higher algal biomass at heated than unheated sites.In summary, warming has here been shown to have major impacts on the phytobenthic community due to a combination of direct effects on physiological processes, as well as indirect effects mediated by interactions among species and trophic levels.
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| 32. |
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| 33. |
- Svensson, Filip, et al.
(författare)
-
In situ warming strengthens trophic cascades in a coastal food web
- 2017
-
Ingår i: Oikos. - : Wiley. - 0030-1299 .- 1600-0706. ; 126:8, s. 1150-1161
-
Tidskriftsartikel (refereegranskat)abstract
- Global warming may affect most organisms and their interactions. Theory and simple mesocosm experiments suggest that consumer top-down control over primary producer biomass should strengthen with warming, since consumer respiration increases faster with warming than plant photosynthesis. However, these predictions have so far not been tested on natural communities that have experienced warming over many generations. Natural systems display a higher diversity, heterogeneity and complexity than mesocosms, which could alter predicted effects of warming. Here we used an artificially heated part of the northern Baltic Sea (the Forsmark Biotest basin) to test how warming influences trophic interactions in a shallow coastal food web with four trophic levels: omnivorous fish, invertivorous fish, herbivorous invertebrates, and filamentous macroalgae. Monitoring of fish assemblages over six years showed that small invertivorous fish (gobiids, sticklebacks and minnows) were much less abundant in the heated basin than in unheated references areas. Stomach content analyses of the dominating omnivorous fish - Eurasian perch Perca fluviatilis - revealed a strikingly different diet within and outside the Biotest basin; gammarid crustaceans were the dominating prey at heated sites, whereas invertivorous fish (e.g. gobiids) dominated at unheated sites. A 45-day cage experiment showed that fish exclusion did not affect the biomass of algal herbivores (gastropods and gammarids), but reduced algal biomass in heated sites (but not unheated). This suggests that warming induced a trophic cascade from fish to algae, and that this effect was mediated by predator-induced changes in herbivore behavior, rather than number. Overall, our study suggests that warming has effectively compressed the food chain from four to three trophic levels (algae, gammarids and perch), which have benefitted the primary producers by reducing grazing pressure. Consequently, warming appears to have restructured this coastal food web through a combination of direct (physiological) and indirect (species interactions) effects.
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| 34. |
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| 35. |
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| 36. |
- Sylvander, Peter, et al.
(författare)
-
Bottom-up control of mesozooplankton thiamine levels in the Baltic Sea
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Thiamine (vitamin B1) is an essential vitamin for many organisms, including all animals. In aquatic systems it is synthesised by prokaryotes and photoautotrophs and transferred to higher trophic levels through predation. This study quantifies for the first time the in situ thiamine concentrations of plankton communities in the brackish Baltic Sea area and analyses which environmental and biotic factors regulate these concentrations. Samples from 93 off-shore stations covering different seasons and two years (2004 and 2005) were included in the analyses. The thiamine concentrations in the phyto- and mesozooplankton varied with season and community composition. Phytoplankton thiamine concentrations were highest in August, which was most likely due to high abundances of thiamine-rich cyanobacteria, and those in the zooplankton were highest in November. The thiamine concentrations in the zooplankton were positively correlated to those in the phytoplankton, which suggests a bottom-up effect for the thiamine status of the zooplankton and possibly also for that of higher trophic levels. A positive correlation between the concentrations of thiamine and the antioxidant zooplankton pigment astaxanthin may indicate an aetiology of thiamine deficiency involving oxidative stress. In both plankton fractions the concentrations of the active vitamin, thiamine diphosphate (TDP), were negatively correlated to phytoplankton C:P ratios, suggesting a coupling between low TDP concentrations and cellular P-limitation in the phytoplankton. Significantly lower TDP concentrations were observed in the phyto- and zooplankton communities in 2005 than in 2004. P-limitation in the phytoplankton cells in 2005 was not related to low availability of dissolved inorganic P in the water. Our results suggest that a low intracellular P-availiability hinders the phosphorylation of thiamine to TDP inside the phytoplankton cells despite the availability of enough P in the water and enough free thiamine in the cells. Further studies are needed to explain the mechanism behind these field observations.
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| 37. |
- Sylvander, Peter, et al.
(författare)
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The thiamine content of phytoplankton cells is affected by abiotic stress and growth rate
- 2013
-
Ingår i: Microbial Ecology. - : Springer Science and Business Media LLC. - 0095-3628 .- 1432-184X. ; 65:3, s. 566-77
-
Tidskriftsartikel (refereegranskat)abstract
- Thiamine (vitamin B1) is produced by many plants, algae and bacteria, but by higher trophic levels, it must be acquired through the diet. We experimentally investigated how the thiamine content of six phytoplankton species belonging to five different phyla is affected by abiotic stress caused by changes in temperature, salinity and photon flux density. Correlations between growth rate and thiamine content per cell were negative for the five eukaryotic species, but not for the cyanobacterium Nodularia spumigena. We demonstrate a high variability in thiamine content among phytoplankton species, with the highest content in N. spumigena. Salinity was the factor with the strongest effect, followed by temperature and photon flux density, although the responses varied between the investigated phytoplankton species. Our results suggest that regime shifts in phytoplankton community composition through large-scale environmental changes has the potential to alter the thiamine availability for higher trophic levels. A decreased access to this essential vitamin may have serious consequences for aquatic food webs.
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| 38. |
- Sylvander, Peter, et al.
(författare)
-
Thiamine concentrations in the Baltic Sea pelagic food web decrease with increasing trophic level
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Thiamine deficiency in top predators has been reported from several aquatic systems. In the Baltic populations of the Atlantic salmon (Salmo salar) this has been observed since 1974, but knowledge of thiamine levels in its prey species is limited. To address this, we measured thiamine concentrations in different tissues of the major Baltic planktivores, Baltic herring (Clupea harengus membras) and Baltic sprat (Sprattus sprattus balticus). Additionally, we measured thiamine concentrations in the major pelagic top predator fish in the Baltic Sea, the Atlantic cod (Gadus morhua) and its prey species along with sprat and herring, the benthic isopod Saduria entomon. Field sampling was conducted during five offshore expeditions in the Baltic Sea proper in 2004, 2005 and 2010. Thiamine was analysed in liver, gonad, stomach and muscle tissues of the fish and the whole body of the isopod. Liver generally had the highest concentrations and muscle tissue the lowest. In contrast to previous reports from other aquatic ecosystems, there was a negative relationship between trophic level and thiamine in the Baltic Sea. Temporal fluctuations of thiamine concentrations in the fish showed the same pattern as previously shown for Baltic plankton communities. Altogether these results suggest a bottom up effect on the thiamine status of the higher trophic levels in the Baltic Sea, possibly influencing the occurrence of thiamine deficiency in Baltic top predators.
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| 39. |
- Sylvander, Peter, 1981-
(författare)
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Thiamine dynamics in the pelagic food web of the Baltic Sea
- 2013
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Thiamine (vitamin B1) is involved in several basal metabolic processes. It is an essential compound for many organisms and in aquatic systems it is mainly produced by phytoplankton and prokaryotes and transferred to higher trophic levels through grazing and predation. The occurrence of thiamine deficiency in top predators has been reported from several aquatic systems. In the Baltic populations of the Atlantic salmon (Salmo salar) this has been observed since 1974 and recently thiamine deficiency has also been reported for Baltic sea birds.This thesis aims at investigating what processes that governs the flow of thiamine from the primary producers to top predators via zooplankton grazers and planktivoric fish. Paper I showed that abiotic stress factors such as salinity, temperature and light conditions can alter the thiamine content of phytoplankton. Paper II showed that abiotic factors indirectly can affect the stress resistance of zooplankton grazers by changing the nutritional quality of their food. In Paper III we found that the in situ thiamine content of zooplankton grazers was directly affected by that of the phytoplankton diet. In Paper IV we found a similar connection between the thiamine contents of Baltic salmon and herring, one of the major salmon prey species. In Paper V we looked at the thiamine content of the pelagic food web of the Baltic Sea as a whole and found a pattern of trophic dilution; the higher the trophic level of an organism (i.e. the further away from the source of thiamine in the food web), the lower was its thiamine content.In all, the results of this thesis suggests a bottom up effect on the thiamine status of the higher trophic levels of the Baltic Sea and that external factors, both natural and man-made, have the capability to affect the thiamine status of the plankton communities and thereby the whole Baltic ecosystem. Thiamine and other micronutrients are not something generally considered in the environmental management of aquatic systems but the results of this thesis suggest that ecological disturbances indirectly can have negative effects on top predators via a disrupted supply of essential substances.
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| 40. |
- Turja, R., et al.
(författare)
-
A multibiomarker approach to the assessment of pollution impacts in two Baltic Sea coastal areas in Sweden using caged mussels (Mytilus trossulus)
- 2014
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 473, s. 398-409
-
Tidskriftsartikel (refereegranskat)abstract
- Blue mussels (Mytilus trossulus) were transplanted in cages for three months in two Swedish coastal areas in the Bothnian Sea (northern Baltic Sea) to investigate the interactions between analysed environmental chemicals and biological responses. A wide array of biological parameters (biomarkers) including antioxidant and biotransformation activity, geno-, cyto- and neurotoxic effects, phagocytosis, bioenergetic status and heart rate were measured to detect the possible effects of contaminants. Integrated Biomarker Response index and Principal Component Analysis performed on the individual biological response data were able to discriminate between the two study areas as well as the contaminated sites from their respective local reference sites. The two contaminated sites outside the cities of Sundsvall (station 51) and Gavle (station G1) were characterised by different biomarker response patterns. Mussels at station S1 showed a low condition index, increased heart rate recovery time and phagocytosis activity coinciding with the highest tissue concentrations of some trace metals, polycyclic aromatic hydrocarbons and organotins. At station G1 the highest organochlorine pesticide concentration was recorded as well as elevations in glutathione S-transferase activity, thiamine content and low lysosomal membrane stability. Significant variability in the geno- and cytotoxic responses and bioenergetic status was also observed at the different caging stations. The results obtained suggest that different chemical mixtures present in the study areas cause variable biological response patterns in organisms.
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| 41. |
- Turja, Raisa, et al.
(författare)
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The mussel caging approach in assessing biological effects of wastewater treatment plant discharges in the Gulf of Finland (Baltic Sea)
- 2015
-
Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 97:1-2, s. 135-149
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Tidskriftsartikel (refereegranskat)abstract
- Biological effects of wastewater treatment plant (WWTP) effluents were investigated in Baltic mussels (Mytilus trossulus) caged for one month 800 m and 1100 m from the WWTP discharge site and at a reference site 4 km away. Significant antioxidant, genotoxic and lysosomal responses were observed close to the point of the WWTP discharge. Passive samplers (POCIS) attached to the cages indicated markedly higher water concentrations of various pharmaceuticals at the two most impacted sites. Modeling the dispersal of a hypothetical passive tracer compound from the WWTP discharge site revealed differing frequencies and timing of the exposure periods at different caging sites. The study demonstrated for the first time the effectiveness of the mussel caging approach in combination with passive samplers and the application of passive tracer modeling to examine the true exposure patterns at point source sites such as WWTP pipe discharges in the Baltic Sea.
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| 42. |
- Verdugo, Josefa, et al.
(författare)
-
Climate relevant trace gases (N2O and CH4) in the Eurasian Basin (Arctic Ocean)
- 2016
-
Ingår i: Deep Sea Research Part I. - : Elsevier BV. - 0967-0637 .- 1879-0119. ; 117, s. 84-94
-
Tidskriftsartikel (refereegranskat)abstract
- The concentration of greenhouse gases, including nitrous oxide (N2O), methane (CH4), and compounds such as total dimethylsulfoniopropionate (DMSP), along with other oceanographic variables were measured in the ice covered Arctic Ocean within the Eurasian Basin (EAB). The EAB is affected by the perennial ice-pack and has seasonal microalgal blooms, which in turn may stimulate microbes involved in trace gas cycling. Data collection was carried out on board the LOMROG III cruise during the boreal summer of 2012. Water samples were collected from the surface to the bottom layer (reaching 4300 m depth) along a South-North transect (SNT), from 82.19 degrees N, 8.75 degrees E to 89.26 degrees N, 58.84 degrees W, crossing the EAB through the Nansen and Amundsen Basins. The Polar Mixed Layer and halocline waters along the SNT showed a heterogeneous distribution of N2O, CH4 and DMSPt, fluctuating between 42-111 and 27-649% saturation for N2O and CH4, respectively; and from 3.5 to 58.9 nmol L-1 for DMSPt. Spatial patterns revealed that while CH4 and DMSPt peaked in the Nansen Basin, N2O was higher in the Amundsen Basin. In the Atlantic Intermediate Water and Arctic Deep Water N2O and CH4 distributions were also heterogeneous with saturations between 52% and 106% and 28% and 340%, respectively. Remarkably, the Amundsen Basin contained less CH4 than the Nansen Basin and while both basins were mostly under-saturated in N2O. We propose that part of the CH4 and N2O may be microbiologically consumed via methanotrophy, denitrification, or even diazotrophy, as intermediate and deep waters move throughout EAB associated with the overturning water mass circulation. This study contributes to baseline information on gas distribution in a region that is increasingly subject to rapid environmental changes, and that has an important role on global ocean circulation and climate regulation.
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- Zie, Jenny, 1982-
(författare)
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Effects of warming on the green alga Cladophora glomerata : Ecological and genetic responses
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Since the beginning of the 20th century, average global surface temperature has increased ~0.7 °C and the current scenarios predict that it will continue to rise additional 2-4 °C during the 21st century. Although many emphasise the need to better understand how warming affect ecosystems on both communities and species level, conclusive data is relatively scarce and our understanding of the effects of warming on community processes and species’ genetic and plastic responses to climate change is still in its infancy.This thesis aims at investigating the ecological and ecophysiological responses to warming of the vegetation in the littoral zone in the Baltic Sea and whether warming affects the genetic composition of the dominant algal species in this zone, the green alga Cladophora glomerata. Warming was studied by comparing properties of the vegetation and the genetic composition of C. glomerata grown in natural communities in unheated sites and heated sites with 3.4-10.3 °C higher water temperature. The studies in this thesis were performed in the Forsmark (60°24'N 18°09'E) and Oskarshamn (57°25'N 16°40'E) areas.The thesis shows that warming changed the community composition in Cladophora-belts, but not the species richness. It also shows that vegetation coverage and height increased with warming. The results also suggest that the vegetation at the heated sites was exposed to lower levels of oxidative stress. The results showed relatively high genetic diversity in the strictly asexual species C. glomerata, but that the genetic diversity decreases with warming. Further, all analyses showed differences between samples from heated and unheated sites and revealed specific patterns for samples from the heated sites. Additonally, C. glomerata at heated sites were more strongly affected by the effect of season than at the unheated sites. An analysis of the genotypic composition of C. glomerata from heated and unheated sites in the two different sub-basins of the Baltic Sea (Forsmark and Oskarshamn) revealed a congruent direction in selection to warming.In all, this new knowledge increases the understanding of how a habitat-forming filamentous alga in a coastal ecosystem may respond to current and future global warming.
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