Spatial and temporal dynamics of the mesozooplankton (Crustacea: Cladocera, Copepoda and Decapoda) in a Pampean shallow hyposaline lake during drought conditions

Resumo

The Sauce Grande Lake, a shallow, eutrophic, and hyposaline lake, was studied through monthly samplings during a year (December 2009- November 2010). The drought that affected the region since 2009 and during the entire study period interrupted the regular inflow from the river and outflow to the Atlantic Ocean. The lake presented an increase of salinity values and highly turbid conditions as a result of the drought conditions and wind resuspension. Small cladocerans such as Moina micrura and the copepod Boeckella poopoensis dominated the mesozooplankton community. The salinity determined the mesozooplankton composition; meanwhile, the abundance dynamic was ruled by temperature in conjunction with the eutrophic conditions during the study period. In a global context of climate change, and in a region where drought and wet cycles are frequent, these results further contribute to understanding the processes affecting the zooplankton community structure and dynamics during extreme climate events.