Effects of glacier melting on the planktonic communities of two Antarctic coastal areas (Potter Cove and Hope Bay) in summer

GARCIA, MAXIMILIANO D.; FERNÁNDEZ SEVERINI, MELISA D.; SPETTER, CARLA; LÓPEZ ABBATE, MARÍA C.; TARTARA, MATIAS N.; NAHUELHUAL, EUGENIA G.; MARCOVECCHIO, JORGE E.; SCHLOSS, IRENE R.; HOFFMEYER, MÓNICA S.

Regional Studies in Marine Science

Elsevier

Lugar: Amsterdam; Año: 2019 vol. 30

2352-4855

Climate change has contributed to the regional retreat and melting of glaciers in the AntarcticPeninsula. This phenomenon is expected to affect the composition of plankton communities. Theaim of this study is to analyze the influence of glacier melting on the composition and structureof phytoplankton and micro- and mesozooplankton assemblages in two coastal areas located in thenorthwest (Potter Cove) and in the northern end (Hope Bay) of the Antarctic Peninsula during summer2013. We expect differences in plankton assemblages between PC and HB related to the fact that theseareas are subjected to different climatic and environmental conditions and that the glacier meltwateris accumulated in lakes in HB whereas the meltwater directly reaches the adjacent sea at PC. However,plankton communities differed according to their proximity to the glaciers in both areas investigated,with a transition from herbivorous to microbial plankton food webs towards the glacier. The microbialfood web was favored under the effects of glacier meltwater due to the stratification of the watercolumn that favors the development of small eukaryotic algae. These are potential prey for ciliates andheterotrophic dinoflagellates which, in turn, favors the development of small omnivorous copepods.Furtherawayfromtheglaciers,theherbivorousfoodwebconsistsoflargephytoplanktonandagreaterrepresentation of herbivorous mesozooplankton organisms. It can be inferred from this study thatincreases in atmospheric temperatures may favor the development of microbial plankton food websin the Antarctic coastal seas during summer due to increased glacier meltwater