Zooplankton Community Structure in Shallow Saline Steppe Inland Waters

Abstract

Several shallow saline waters can be found in Central Asia in arid steppe climate, but our knowledge of their zooplankton community has been so far rather limited. The aim of our research was to provide data on the steppe zooplankton community in a large-scale regional study. Therefore, a baseline survey was carried out in 23 shallow inland waters of different salinity in Northern Kazakhstan. We measured the quantity and identified the taxonomic composition of zooplankton in the spring period and examined changes in community structure in correlation with salinity. Lesser salt concentration of the hyposaline–mesosaline waters was indicated by the presence of halophilic rotifer species: Brachionus asplanchnoides, Br. dimidiatus, Br. plicatilis. Mesosaline and hypersaline waters were indicated by the presence of halobiont crustaceans: Moina salina, Arctodiaptomus salinus, Cletocamptus retrogressus. Very high concentration of salt was indicated by presence of Artemia alone which is the only group, that can tolerate and adapt to this extreme environment. In the hypersaline waterbodies at over 79 gL−1 high TDS conditions a very simple tropical structure was found. Artemia playing monopolistic ecological function in the zooplankton community. We identified three characteristic groups of shallow inland saline waters based on their zooplankton composition.