Late Holocene changes in cyanobacterial community structure in maritime Antarctic lakes

摘要: Despite the dominance of cyanobacteria in polar freshwater aquatic ecosystems, little is known about their past biodiversity and response to climate environmental changes. We explored use light microscopy microfossils, high performance liquid chromatography fossil pigment composition denaturing gradient gel electrophoresis 16S rRNA genes study present-day differences cyanobacterial community structure changes two adjacent maritime Antarctic lakes with contrasting depths (4 26 m) climates. Light was limited because degradation cell structures. Fossil concentrations were below detection limits our method several sediment samples deep lake, but abundant diverse core from shallow pond, probably as a consequence increased availability and/or more benthic flora. Total carotenoid chlorophyll highest both between ca. 2,950 1,800 cal yr BP, which coincides late Holocene optimum recognised elsewhere Antarctica. Cyanobacterial molecular diversity higher top few centimeters sediments lakes. In deeper sediments, taxonomic turnover appeared be relatively small anomalies lakes, underscoring broad tolerance variability. This, however, may part explained by low resolution obtained conserved gene preferential preservation particular taxa. Our results highlight potential DNA lake colonization succession dynamics lacustrine warrant further investigation factors that affect DNA.