Data on the pioneer vegetation of the Lake Velence

Abstract

Lake Velence is one of Hungary's largest saline lakes. Part of its natural dynamics is that certain parts of the lake bed regularly dry out, providing pioneer surfaces suitable for the emergence of plants of the mudflats and drying (saline) ponds. During the particularly dry year of 2022, the water level was per­manently and significantly low, allowing to study the vegetation of the dry lake bed. In the first half of the last century, the natural vegetation of the lakeshore (including salt steppes) was studied, but there are very few records of the pioneer species of the lake bed. The salt steppes around the lake have now largely declined, but due to low water levels, some of their characteristic species are still present in the lake bed (though, usually in low number of individuals). Examples include Crypsis aculeata, Cyperus pannonicus, Suaeda pannonica, the once abundant Suaeda prostrata, and the previously rare Crypsis schoenoides and Spergularia salina. Spergularia maritima was once widespread but currently not found in the lake bed. Although, Schoenoplectus litoralis is not a member of the ephemeral vegetation, but is a characteristic plant of the littoral zone of Lake Velence. This species probably appeared therein the middle of the last century and is currently spreading.