Late-Glacial/Holocene changes of the climatic and trophic conditions in three Eifel maar lakes, as indicated by faunal remains. 1. Cladocera

The oligotrophic Weinfelder Maar, on the one hand, and the eutrophic Schalkenmehrener Maar and Holzmaar on the other, showed distinct differences in their planktonic and benthic cladoceran faunas since the beginning of the Holocene. In the Weinfelder Maar, Bosmina longispina occurred in the Late-Glacial and early Holocene. It was not detected in the other two maar lakes. In the latter, there was a dramatic change in the structure of the chydorid community as indicated by a strong decrease in species diversity and an increase in the abundance of small Alona species in the Atlantic period induced by eutrophication. The climatic change at the Late-Glacial/Holocene boundary was not reflected by an increase in chydorid diversit