An explosion of Cladocera numbers in a potential post airburst environment in the Stará Jímka paleolake, Central Europe
Abstract
Cladocera have occurred in the central European lakes from the time of ice ages and it is not entirely clear what contributed to their spread during this period. We collected a Late Glacial lake sediment at the Stará Jímka paleolake (the Bohemian Forest Mts, southern Bohemia, Czech Republic) and showed the data on Cladocera in parallel with lacustrine proxies like loss on ignition (LOI), P, Al, Ca concentration, the amount of plankton and benthic algae, and chironomid taxa (Fig. 1).
Our data shows that a significant burst in Cladocera numbers preceded the find of molten fragments in the sediment, mostly microscopic spheres (MSP; diameter from 10 to 40 μm), that are thought to originate from an airburst at the Younger Dryas boundary. This goes parallelly with variation of plankton and benthic algae and chironomids.
Nevertheless, while some chironomids increased in numbers after the MSP occurrence, there were also some whose numbers decreased. The explosion of Cladocera numbers after the potential airburst may be an important indicator of ecosystem changes during the airburst occurrence.