Pauline J. M. Snoeijs

• PhD Plant Ecology, Uppsala University
• Professor at Stockholm University

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 avai...

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...

Thiamine (vitamin B(1)) 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 de...

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...

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 co...

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 o...

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)...

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 nat...

1. Geographical position, geological development, hydrographical features, climate and physical drivers together create the Baltic Sea environment. 2. Baltic Sea water is brackish and characterised by pronounced salinity gradients , both in horizontal and vertical directions, because of the large volume of freshwater runoff from over 100 rivers, wh...

1. Phytobenthic communities consist of macrophytes (macroalgae, vascular plants and mosses) with their accompanying fauna and microorganisms. 2. The phytobenthic communities occur in the photic zone, which in the Baltic Sea extends from the water surface down to a ~20 m water depth, but in turbid coastal waters only down to ~5 m. 3. The type of veg...

1. More than 4,400 known species live in the brackish Baltic Sea. Of these, 4 % are cyanobacteria, 51 % unicellular eukaryotes (protists), 8 % macrophytes, 32 % invertebrates and 5 % vertebrates. 2. In the Baltic Sea Area (Baltic Sea and the transition zone ), the species richness of these five groups is >6,600, 50 % higher than in the Baltic Sea a...

The concentration of greenhouse gases, including nitrous oxide (N2O), methane (CH4), and compounds such as total dimethylsulfoniopropionate (DMSPt), 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,...

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 car...

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 colo...

We performed laboratory experiments to investigate whether the synthesis of the antioxidants α-tocopherol (vitamin E) and β-carotene in phytoplankton depends on changes in abiotic factors. Cultures of Nodularia spumigena Mertens ex Bornet & Flahault, Phaeodactylum tricornutum Bohlin, Skeletonema costatum (Greville) Cleve, Dunaliella tertiolecta But...

Rapport / Naturvårdsverket, ISSN 0282-7298 ; 3369 Pages: 59 p.

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 nu...

This is a review paper