Under ice plankton and lipid dynamics in a subarctic lake.

Climate warming causes shorter winters and changes in ice and snow cover in subarctic lakes, highlighting the need to better understand under-ice ecosystem functioning. The plankton community in a subarctic, oligotrophic lake was studied throughout the ice-covered season, focusing on lipid dynamics and life history traits in two actively overwintering copepods, and Whereas was overwintering in C-IV to C-V stage, reproduced under ice cover. Both species had accumulated lipids prior to ice-on and showed a substantial decrease in total lipid content throughout the ice-covered period: (60%-38% dw) and (73%-33% dw).

Selective Fatty Acid Retention and Turnover in the Freshwater Amphipod .

Gammarid amphipods are a crucial link connecting primary producers with secondary consumers, but little is known about their nutritional ecology. Here we asked how starvation and subsequent feeding on different nutritional quality algae influences fatty acid retention, compound-specific isotopic carbon fractionation, and biosynthesis of ω-3 and ω-6 polyunsaturated fatty acids (PUFA) in the relict gammarid amphipod . The fatty acid profiles of closely matched with those of the dietary green algae after only seven days of refeeding, whereas fatty acid patterns of were less consistent with those of the diatom diet.