In this study, the chironomids of five shallow lakes in northern Germany were investigated
using a freeze corer technique for sampling. The aim of the study was to analyse the chironomid
assemblages to find evidences for the historical status of the various lakes concerning
taxonomic composition, lake productivity and habitat (macrophyte coverage). Chironomid
head capsules from sediment layers of various time periods (from before 950 A.D. to 1950
A.D.) were identified. Based on the taxonomical and ecological analysis, different lake types
are pointed out. Over the time span studied, some lakes were conservative in taxa composition
and ecological functions, while others changed between periods. These results suggest
that no single pristine lake status can be inferred for shallow lakes, but different ones have to
be considered, reflecting the individual history and situation of each lake.
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