Ground vegetation cover at 47 lake sites in Central and Eastern Yakutia, Siberia, in summer 2021 (RU-Land_2021_Yakutia)

The vegetation surveys were carried out in four different study areas in the Sakha Republic, Russia: in the mountainous region of the Verkhoyansk Range within the Oymyakonsky and Tomponsky District (Event EN21402 - EN21415), and in three lowland regions of Central Yakutia within the Churapchinsky, Tattinsky and the Megino-Kangalassky District (Event EN21416 - EN21464). The study area is located within the boreal forest biome that is underlain by permafrost soils. The aim was to record the projective ground vegetation in the shore area of the lakes studied during the RU-Land_2021_Yakutia summer field campaign in August and September 2021. Baisheva et al. (2022) gives an overview of the lakes studied and the corresponding hydrochemistry. The ground vegetation was estimated as a percentage within 2 x 2 m plots. The location of the plots was selected on site at the lake to represent the typical ground cover. Some of the vegetation plots were located directly on the shore in the transition to the water, others were chosen nearby the lakeshore. The elevation corresponds to the lake level, as the plots were in the immediate vicinity. The number of plots per lake depended on the different land cover classes, with more plots selected if the vegetation cover was more heterogeneous. The vegetation cover was estimated for each taxon within the plot. If only a few specimens of a species were represented within the plot (less than 1%), they are marked with '< 1'. If many specimens of a species were represented in a plot (up to 5%), they are designated as ' 1.70 m) and trees (> 3-5 m). In total, 92 plots at 47 lakes were investigated. All data were collected by scientists from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) Germany, the University of Potsdam Germany, and the North-Eastern Federal University of Yakutsk (NEFU) Russia.