Soil-dwelling Collembola in coniferous forests along the gradient of pollution with emissions from the Middle Ural Copper Smelter

The results of three-year studies on Collembola communities in spruce-fir forests along the gradient of pollution with emissions from the Middle Ural Copper Smelter (Revda, Sverdlovsk oblast) are presented. They show that the species and ecological structure of these communities change abruptly in the impact zone (1 km from the source of emissions), compared to the background zone (30 km from the source), which involves a decrease in the abundance and diversity of Collembola. Their total abundance and species richness in the zone of intermediate disturbance (7 and 4 km) are considerably higher than in the background zone, and the species structure of communities is characterized by superdominance. Four species groups differing in sensitivity to pollution are distinguished. Preference for zones with different pollution levels in closely related species is regarded as a case of ecological vicariation.