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The developmental history of shallow, eutrophic Lake Glebokie Uścimowskie, eastern Poland, spanning the last 180 years, was studied using analyses of pollen, plant macrofossils, diatoms, chlorophyll and carotenoid pigments, Cladocera, Chironomidae and geochemistry from lead-210 dated sediment cores. The lake was colonised by macrophytes and eutrophic through the whole investigation period, but from 1950 AD the trophic status increased slowly and eutrophication accelerated after 1980 AD, leading to hypertrophy. Despite this eutrophication history, macro- and microfossils indicated the continuing presence of Isoetes lacustris spores and Elatine hydropiper seeds in the sediments of the lake, even though neither species were encountered in the recent and present-day lake macrophyte surveys. Both the species are classified as vulnerable (IUNC List) in Poland and are presently deemed extinct due to eutrophication in the Łeczna-Wlodawa Lake District. We conclude the silica-rich substrates (51–77%), low in calcium ( |
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