Cladocera and Anostraca from the Interior Plateau of British Columbia, Canada, as paleolimnological indicators of salinity and lake level

Cladoceran and anostracan species assemblages were identified from the surface sediments of 33 closed-basin lakes from the southern Interior Plateau of B.C. in order to explore their effectiveness as quantitative indicators of lakewater salinity and ionic composition. These lakes were chosen to maximize the range of lakewater salinity concentrations (freshwater through hypersaline) as well as brine composition (sulphate and carbonate dominated systems). The distribution of the anostracans and cladocerans were strongly correlated with lakewater salinity, ionic composition and lake depth. Based on these strong relationships significant predictive models were developed, using weighted-averaging techniques, to infer lakewater salinity based on the species composition of anostracans and cladocerans in surface sediments. Furthermore, models were developed to infer lake depth that are superior to previously used techniques based on the ratio of planktonic/littoral Cladocera. Given that the species composition of anostracans and cladocerans can be used to infer changes in salinity and lake level, and that their remains can be identified from sedimentary profiles, there is considerable potential in using their assemblages as paleolimnological indicators of past climatic conditions.