Water Resources of Transboundary Rivers in the Steppe Zone Under Modern Hydroclimatic Conditions

Abstract

We analyzed the current condition and use of water resources in the steppe zone, considering the current hydroclimate change trends. Besides, we established an increase in the surface temperature in the Ural River basin, primarily in frost-free seasons. In addition, we revealed a stable trend in the seasonal distribution of precipitation within the transboundary basin of the Ural River. Also, we confirmed the transformation of the annual flow distribution in the Ural River basin, which is characterized by a decrease in the share of spring runoff and an increase in winter runoff. This trend was verified by an increase in the value of the minimum runoff in winter. Then, we determined the regional differences in the structure of water consumption due to natural-zonal and socio-economic factors. Considering the water supply indicators in the transboundary basins of the steppe zone, we estimated the anthropological burden on water resources. Furthermore, we discuss the need to take into account existing water resources, especially in low-water years. Also, we identified regions that are characterized by a moderate load on water resources and low values of potential water supply. The paper deals with the need to improve the efficiency of the use of water resources of transboundary rivers, which can be achieved by reducing the volume of irrevocable withdrawal of runoff and losses due to water transport. These factors reduce the Gross Regional Product and increase the recycled water in the structure of water consumption. As a result, we emphasize the relevance of developing international programs for water resources of transboundary rivers, which would be developed based on the basin approach and the integrity of river basins separated by national borders.