ИСТИНА

The land cover of the catchment area is an important factor in the runoff formation process. Changes in the structure of land use can indirectly affect the water availability in different seasons of the year. The Don basin is one of the most developed river catchments in Russia. During last 9 years a continuous long-term low flow period has been observed in this region. The main cause of the drought is undoubtedly climatic factors - rainfall deficit and positive temperature anomalies. However, the intensification of economic activity can also affect the formation of water shortages. Based on the analysis of the Landsat archive of images, the dynamics of land use in the Don basin was studied. Several key dates have been chosen: the mid-1980s, the mid-1990s, the mid-2000s and the last 2-3 years, corresponding to the drought period. The analysis was carried out for three key areas - the Upper Don, Khoper and Lower Don area. As a result of the automated classification, the following classes of objects were distinguished: water objects (rivers and ponds), forests, fields and pastures, anthropogenic objects. From 1985 to 2015, the Khoper basin is characterized by an increase in forestation from 10.0% to 15.2% and a slight increase in anthropogenic development. The increase in the area of water bodies in the 1980s - the 1990s was followed by a decline in the early 2000s. From 2007 to 2014 the area decreased almost twice (from 0.90 to 0.49%). For the Upper Don, the increase in the forest area from 870 km2 to 3580 km2 is even more evident. Thus, from 1996 to 2014, the area occupied by forest increased 4-time (from 1.2 to 5.2% of the total). The area of anthropogenic objects also increased (from 5.3% to 7.8%) due to the expansion of the private sector and the growth of industry since the mid-1990s. The Lower Don is characterized by a sharp increase in the urban area observed since the late 1990s. This increase could become an additional factor in the formation of water shortages