GEOINFORMATION ANALYSIS OF PASTURE RESOURSES OF ECOTON "MALY SIRT - CASPIAN LOWLAND"
Introduction. The relevance is due to the features of the ecotone landscape, which are determined by the transition from the steppe zone to the semi-desert, where the state of the landscape components is dynamic and to a large extent depends on external conditions. Identification of patterns of changes in the state of the landscape will provide an opportunity to scientifically substantiate the rational use of natural resources for efficient business operations. Object. The study area is the ecotone «Maly Syrt - Caspian Lowland», the southern boundary of the ecotone passes along latitude 49° 30', the northern border 51° 20' from the Volgograd reservoir in the west to a longitude of about 49°. Materials and methods. The study is based on arrays of statistical data on the number of livestock in farms of all categories, remote sensing materials obtained from MODIS spectroradimeter and thematic maps (landscape map of the USSR, data on the underlying surface). All data was re-projected and converted to a vector format for working in the geographic information environment QGIS. For pastures, the weighted average values of the vegetation index in the context of municipal districts and genera of landscapes were calculated. Weighing was carried out on the basis of areas occupied by areas with certain values of the vegetation index. Results and conclusion. It is established that in the research region, pastures occupy a large part of the territory - 62.8%, another 19% is represented by a mosaic of arable land and pastures due to inconvenience. The number of cattle in the last decade has been quite stable and amounted to 300-340 thousand heads in different years. The increase in cattle stock in Zhanibeksky (by 71%), Kaztalovsky (by 47%), Bykovsky (by 33%) and Rovensky (60%) districts was offset by a corresponding decrease in the Saratov region (on average by 30-40%). Approximately 82% of pastures belong to semi-desert landscapes, about 17% - to steppe. Most of the pasture land (54.8%) has NDVI values of 0.3-0.35, another 34% of NDVI pastures varies from 0.35 to 0.40. The most productive pastures are located in the Kaztalovsky district of the West Kazakhstan region and the Sovietsky and Fedorovsky regions of the Saratov region. The least productive pastures in Dergachevsky, Aleksandrovo-Gaysky, Novouzensky, Pitersky and Rovensky districts of the Saratov region.