ECOLOGICAL AND AGROCHEMICAL ASSESSMENT OF THE KAMENNAYA STEPPE SOILS UNDER FOREST CENOSIS

A set of parameters of soils under forest belts was studied. The objects of research were old-growth (65-68 yrs) ravine and shelteroelt forest plantations of the Kamennaya Steppe. The results allow assessing the trends of changes in soil characteristics over a long period of time. Key plots of 100x 100 m were laid out using a regular sampling grid. The sampling interval is 15-25 m. A positive effect of forest sheltelbehs on the properties of chernozems was found. There is an increase in thickness of the humus horizon from 42.3 cm (arable land on the slope) to 72.6 +/- 5.1 cm (under forest). The maximum values are typical for chernozems of watershed areas: 59.6 +/- 2.4 cm (amble land) and 85.6 +/- 3.9 cm (forest belt). Chernozems leached due to the activation of migration processes of carbonates into the underlying soil horizons have the maximum depth of soil effervescence. Chernozems zooturbated due to mechanical transport and mixing of accumulative-carbonate horizon have the lowest depth of soil effervescence. A general trend to decrease the depth of soil effervescence under the forest cenosis was found. The highest humus content is observed in watershed areas: 7.14 +/- 0.24 % (arable land) and 8.56 +/- 0.18 % (forest belt). A ravine forest belt reduces the risk of erosion processes. A fairly strong humus profile with a high content of organic matter: 7.03 +/- 0.27% (under forest) and 6.10 +/- 0.10% (on amble land), was possible to preserve on amble lands in the zone of the belt's influence. The planting of forest belts causes a change in the nature of vegetation. The influence of acidic products of litter decomposition formed soil horizons with a moderately acidic reaction of the environment in the humus layer. Despite the leading position of calcium, an increased content of magnesium was found in the composition of exchange-absorbed cations. Forest belts have become especially important in recent decades due to changing climatic conditions. In the steppe regions of Russia, such plantations are a powerful soil conservation factor that helps stabilize and increase soil fertility. It is necessary to intensify the planting of artificial forest stands in the steppe regions of Russia.