Hydrological aspects of the Nogai steppe desertification (north-west of the Republic of Dagestan)

Abstract

The problem of desertification is one of the most pressing problems of mankind. In Russia, this problem is most acute in the south, including in the Republic of Dagestan. This article addresses some hydrogeological aspects of desertification in the Nogai District of the Republic of Dagestan. Desertification of the territory of the Nogai District of Northern Dagestan can be directly related to the widespread decline in the groundwater level. Based on the results of the analysis of the work of domestic scientists and the conducted research, the interrelation of the hydrogeological problems of flat Dagestan with the development of desertification has been revealed. The problems of the irrational use of groundwater of the Nogai district are considered. The use of forced pumping in artesian wells and the transition to the development of deeper aquifers reinforces the overall depression. Considering that in Nogai district pressure water can be considered the main source of groundwater recharge or supply, long term spontaneous use of water resources can lead to depletion of groundwater, which requires urgent measures. Currently, the anthropogenic load is high: a large number of artesian wells and pipelines are in operation. In order to avoid further expansion and strengthening of pollution processes in the groundwater of the SDAB, most artesian wells are subject to major repair or liquidation. It is also required to conduct a widespread assessment of the level of pollution in the territory of the Nogai district for a comparative analysis and identification of the dynamics of growth or reduction of pollution of groundwater. Since, due to the deterioration and corrosion of well equipment, water is discharged to the surface of the territory in large volumes, hydrogeological and ecological inspections of the wells of the territory are necessary with the further creation of sanitary protection zones. The established hydrodynamic mode of operation of artesian wells in the Nogai district contributes to a decrease in piezometric levels, as well as the infiltration of saline waters into aquifers, which lead to the development of desertification. In order to overcome the geo-ecological problems associated with desertification in the Nogai district, comprehensive work is needed to study, monitor and prevent the depletion and pollution of groundwater resources.