RETROSPECTIVE ANALYSES OF SOIL FERTILITY CHANGE IN THE STEPPE ZONE OF UKRAINE

Abstract

Traditional agriculture can be characterized as having high indicators of economic efficiency, but its implementation entails environmental consequences that ultimately lead to pollution of the natural environment and a decrease in soil productivity. The productivity of the soil can be determined by its ability to meet the needs of plants in moisture, nutrients, and air, as well as to provide conditions for their normal functioning in order to obtain stable and high yields, that is, by its fertility. The rational use of soils in agriculture, the development, planning and effective use of a set of measures for the management and regulation of soil fertility must begin with the determination of their actual agro-ecological state, which must be considered as a set of physico-chemical, agrophysical, biological and agrochemical properties, as well as soil pollution radionuclides, heavy metals, pesticides and other toxic substances. In order to determine the productivity of soils, their spatial-temporal heterogeneity and their value, it is necessary to use indicators of agrochemical and ecological assessment of soils. Points for soil grading are calculated in accordance with the method of agrochemical certification of agricultural land, which was invented by Ukrainian scientists S.A. Balyk and I.P. Yatsuk. To assess the condition of the soils of the Steppe zone of Ukraine and determine changes in their agroecological properties along with their fertility, an analysis of the results of the XI round of continuous agrochemical certification of agricultural lands of the Steppe zone of Ukraine, conducted by the Kherson branch of the State Institution "State Soil Protection", using information from 296 soil sampling stations. A retrospective study of soils was carried out according to their main agrochemical indicators with the use of modern geoinformation technologies. The spatiotemporal changes in the content of the main indicators of soil fertility are outlined using the results of ten rounds of soil surveys: from II (1970–1974) to XI round (2017–2021). Using the built-in functions of the ArcGIS 10.1 software, models of spatio-temporal changes in the agro-ecological state of the soils of the Steppe zone of Ukraine were developed based on the main agrochemical indicators.