Spatial Organization of the Bird Population in the Middle Taiga of the Western Siberian Plain

Resumo

Based on long-term route surveys, the bird population is studied in the least ornithologically investigated subzone of western Siberia, in the middle taiga all along its length from the Trans-Ural region to the Yenisei valley and in all types of landscapes. It is established that the species richness of the birds and the population density increase under replacement of dark coniferous species with small-leaved species, the impact of the floodplain regime and eutrophic swamping, and an increase in mosaicism and productivity of biocoenoses. It is noted that a decrease in the number of species and individuals in bird communities is associated with the replacement of dark coniferous small-leaved forests by pine forests or wooded mesotrophic and eutrophic bogs and then upland bogs. It is shown that the frequent trends of impoverishment of bird communities are determined by industrial and residential transformation of landscapes and the transition from land habitats to water ones.