Key factors of avian diversity and sustainability in the forest-steppe lakes of Western Siberia

The article examines the relationship between various parameters of 25 forest–steppe lakes in Western Siberia and the biological diversity of bird communities, based on bird censuses conducted from 2002 to 2023. It focuses on factors such as the lakes' physical characteristics, climate zone peculiarities, salinity levels, lake area, and the extent of overgrowth. A total of 180 bird species typical of the Western Siberia forest–steppe zone were recorded. The study found a statistically significant differentiation in bird communities across subzones, with the mean total bird abundance in the middle forest–steppe being 2.5 times greater than that in the northern forest–steppe. Correlation analysis revealed a significant inverse relationship between lake salinity levels and both species number and total bird abundance, as well as the species diversity and resilient sustainability indices of water bird communities. Conversely, a significant direct influence of salinity on the resistant sustainability index was observed. Additionally, a statistically significant, albeit weak, positive correlation was found between total bird abundance and the degree of lake overgrowth by aquatic and semi-aquatic vegetation. However, no clear correlation was established between the area of the lakes and the examined properties of bird communities.