Salinization of irrigated agricultural lands in the Altai Territory

Abstract

Introduction. The Altai Territory is the leader among the subjects of the Siberian Federal District in terms of the area of arable land, of which more than 80% is located in the zone of unstable moisture. Irrigation predominates among agricultural hydrotechnical land reclamation in the region. The area of irrigated land is 69 thousand hectares, of which almost 10 % have varying degrees of salinity in the root layer. Prolonged irrigation of land and non-compliance with irrigation technologies can lead to salinization of lands in irrigation systems. The purpose of the research: spatio-temporal assessment and clustering of salinization of irrigated lands in the context of municipal districts and agrochemical zones: steppe, forest-steppe and foothills. Material and methods. In Russia, all irrigation systems have uniform rules for collecting data on the state of land, conducting soil-salt surveys and laboratory processing of their results. The research material was observational data on the salt regime of lands in irrigation systems of the Altai Territory for 2013-2022, data from annual state monitoring of lands, information on irrigated lands and the technical condition of reclamation systems from the reclamation cadastre. The research methods were general scientific methods (analysis and synthesis), applied mathematical methods (regression and cluster analysis), scientific methods of hydraulic engineering agricultural reclamation. Results and discussion. Based on the reclamation cadastre data, an analysis of the state of irrigated agricultural land was carried out according to the degree of salinization. A model of the dynamics of the area of highly and very highly saline lands was constructed, statistical assessments of the quality of the model were checked, and the average rate of annual increase in the area of lands subject to salinity was determined. An analysis has been made of the most possible causes of salinization on irrigated lands, which include high levels and salinity of groundwater, high salinity of water used for irrigation. Calculations were carried out, among other things, for agrochemical zones: steppe, forest-steppe and foothills. The dynamics of areas with different groundwater levels, groundwater salinity and irrigation water were assessed. Based on data for the beginning of 2015 and 2022, a cluster analysis of the regions of the Altai Territory was carried out according to the degree of salinization of irrigated agricultural lands. The dynamics of changes in the number of regions and the area of irrigated land in clusters is analyzed. In conclusion, the calculation results are summarized and general conclusions are drawn about the dynamics and possible reasons for changes in the studied indicators. The results can be directly used by government authorities and organizations of the reclamation complex of the Altai Territory.