Ecological assessment of the territory, taking into account the functional heterogeneity of certain categories of lands

Widespread degradation of natural ecological systems dictates the need to establish their stability limits, which are largely reflected in the change of the environmental components properties as a result of various factors, primarily anthropogenic ones. Sustainability is expressed by a coefficient defined as the ratio of the areas of the territories under the elements of a favorable and negative impact. Determination of the coefficient of ecological stability implies taking into account the ecological significance of each of the biotechnical elements of the terrain. This methodology assumes several stages of research: analysis of the structure of the land fund of the region, identification of priority categories of land, assessment of the contribution of individual biotechnical elements within the categories in maintaining environmental sustainability and stability. The research was carried out on the territory of the Orenburg Region, where the agro-industrial sector prevails, characterized by a high rate of growth of disturbed lands. The assessment was carried out for the period from 2002 to 2016. The study showed that agricultural land is a priority area, accounting for 88,5% of the total area. They are divided into arable land (55,9%), fodder land (43,5%), perennial plantations (0,5%) and other lands (0,1%). The value of the stability coefficient during the whole period of the study is on average 0,36, which is 29,5% below the minimum norm and characterizes the territory as unstable. The maximum value of the stability index is 0,79 with an optimal value of at least 1, which allows us to classify the research area as «less stable». The obtained values of the parameters studied make it possible to draw conclusions about going beyond the limits of the stability of the ecosystems in the Orenburg Region and violating the stability of their development. Reducing the burden on the land fund of the region under study will allow a differentiated approach, based on the system of ecological zoning.