COMPARATIVE ANALYSIS OF THE CONTENT OF HEAVY METALS IN SOILS OF AGRICULTURAL LANDSCAPE
The results of the evaluation of the content of heavy metals in the soils of agrolandscape are considered in the article. Data of the gross content and concentration of mobile forms of heavy metals in the components of the agrolandscape are analyzed by their average values. The averages are almost identical for both forms of metals in crop rotation. If the content of some heavy metals differs in crop rotation from the average in agrolandscape, then it is insignificant. This is explained by the fact that the share of crop rotation in the total area of the agricultural landscape is about 95% and the influence of other components on average values is insignificant. The share of some metals in the gross and mobile forms in the soils of forest belts is slightly higher than the average for the agrolandscape. This is due to their higher content in the exchange funds of the underlying rocks. Concentrations of most heavy metals in soils of natural lands, which are mainly under conditions of accumulation of substances (floodplain and valley of the river, bottoms of beams), due to an increase in the rates of application of mineral fertilizers on agricultural fields increased markedly in 2015 compared to 2010 and especially from 2006 This bond is clearly visible for cadmium, zinc, copper, cobalt and nickel. The following conclusions can be drawn based on the assessment of the gross content of heavy metals and the concentration of their mobile forms in the soils of the agrolandscape and its components according to the results of areal surveys in 2006, 2010 and 2015 years: total area of the monitoring site is 450 hectares, or about 6-7% of the total agricultural land area; comparison of data on the gross quantity and content of mobile forms of individual metals by monitoring sites was carried out on 92 (copper, nickel, cadmium) and 98%. Comparative analysis of data on the content of heavy metals in gross and mobile equivalent for soils of the entire agrolandscape and monitoring site showed a high correlation (by 90-95%) of the results, which is confirmed by the correctness of the choice of the monitoring spot. Field survey of heavy metals in 2006, 2010 and 2015 years showed on a number of elements a noticeable increase in their content, especially during the last five-year period, within 8-10%; the concentration of other elements increased even more noticeably - up to 70%. The results of areal surveys of the content of heavy metals in the soils of the agrolandscape provide grounds for developing a program to control the dynamics of heavy metals to reduce their impact on the productivity and quality of crops.