Retrospective studies of soil fertility change on the example of the Kherson region (Ukraine)

Abstract

Traditional agriculture is characterized by high indicators of economic efficiency, but the ecologic consequences of its implementation cause a decrease of soil productivity and environmental pollution. Soil productivity is determined by its fertility – an ability of the soil to meet the needs of plants in the elements of nutrition, moisture, air, as well as provision of the conditions for their normal live to obtain stable yields. Rational use of land resources in agricultural production, the development and effective use of a complex of measures for the regulation and management of soil fertility is not possible without identifying their actual agroecological state, which is considered as a combination of agro-physical, physical-chemical, agrochemical and biological properties, and also soil contamination by heavy metals, radionuclides, pesticides and other toxicants. To determine the productivity of soils, their value and spatial-temporal heterogeneity, indicators of ecological agrochemical evaluation of soils are used. The calculation of points for soil evaluation is carried out in accordance with the methodology of agrochemical certification of agricultural lands developed by known Ukrainian scientists I.P. Yatsuk and S.A. Baluk. In order to determine the changes in the agroecological properties of soils of the Kherson region and to assess their fertility state, the results of the XI-th round of agrochemical certification of agricultural lands of the region, conducted by the State Institution “Institute of Soil Protection”, based on data from 296 stationary facilities, are presented. Retrospective soil studies according to the main agrochemical indicators using GIS-technologies are carried out. The spatial-temporal changes of the content of the basic soil fertility indicators are presented based on the results of ten five-year survey tours: From II (1970 – 1974) to the XI-th round (2013 – 2017). Using ArcGIS 10.1, spatial-temporal models of changes in the agroecological state of soils in Kherson region based on the main agro-chemical parameters were developed.