Ecological and Functional Properties of Steppe Soils under Moderate Anthropogenic Impact

Abstract

Steppe soils of a small industrialized city with moderate anthropogenic impact for example Krasny Kut, Saratov region were analysed to ascertain their ecological and functional state. In the course of this work, the concentration of heavy metals (Zn, Cu, Pb, Ni, Cr and Cd) was determined in the soil samples, including the hazard coefficient (Kо) and the total contamination coefficient (Zc). Magnetic susceptibility, magnetic coefficient (Kmag), thermomagnetic effect (dk) of the soil samples were analysed together with the activity of soil enzymes (dehydrogenases, catalases, peroxidases and invertases). Using ecological and geochemical analytical methods, a widespread excess of maximum permissible concentration (MPC) of mobile forms Ni, Pb, Cu and Zn was recorded in the soil samples of Krasny Kut, and a single excess of MPC was observed for Cr and Cd. According to Zc indicator values, 4 samples were classified as soils with moderately dangerous levels of contamination and 2 samples with dangerous levels of contamination. Using petromagnetic analysis, a few samples were observed to contain a moderate amount of introduced technogenic magnetic particles and one sample with a hazardous amount of introduced technogenic magnetic particles. Medium, high and very high levels of dehydrogenase, catalase, peroxidase and invertase activities were recorded in the soil samples, indicating the absence of ecotoxicants inhibiting the enzymes. The observed peculiarities in the ecological and functional state of soils, representative of the steppe zone of the Eastern part of the European territory of Russia will be required for monitoring, reducing and forecasting the anthropogenic burden on soil ecosystems.