Home – Home – Jornals – Contemporary Problems of Ecology 2020 number 5

Studies of communities of ground beetles (Carabidae) and black beetles (Tenebrionidae) were conducted in Central Kazakhstan along 70°E. Investigations were made in typical, dry and deserted steppe subzones in 1976-1978 and 2018. In parallel, soil cover studies were conducted and climate indicators of the studied areas were compared. Considerable change of a climate for 50 years expressed in rise in temperatures with simultaneous increase of precipitation. The basic features of soils have not undergone essential changes, but keep or get strong potentials to salinization. The generality of local fauna of carabids in 1976-1978 was 48-62 %, in the beginning of XXI century it decreased in dry steppe to 16 %, in deserted steppe - to 7 %. In tenebrionids which are more adapted to aridity the faunal similarity decreased from 70-75 % to 37 % in the typical steppe, and increased to 87 % in dry steppe. There are more “southern” subarid species in the communities and fewer relatively “northern” boreal and polysonal species, which disappear completely in dry and desert steppes. As an integral zoo-indicator of changes in aridity of the environment, the Tencar index, expressing the ratio of the number of individuals and species of arid tenebrionids and more humic carabids, was used. In the typical steppe the index values are low and change little in the long-term dynamics and along the catena. But in the dry steppe Tencar Index values in 2018 increased by 5 times compared to the middle of the XX century, and in deserted steppe - by 2 orders of magnitude. The trigger for changes in the composition and structure of local communities of beetles is not a change in atmospheric humidity, but the rise in average annual temperatures, which exceeded the global trend values and activated salinization of soils, creating the conditions for desertification of the territory and biota.