Evaluation of the spatial and temporal changes in groundwater level and mineralization in agricultural lands under climate change in the Syrdarya province, Uzbekistan

Abstract

Abstract Salinization processes are taking place as a result of rising groundwater level and its mineralization rate due to inefficient and unsustainable use of water and land resources in Uzbekistan. This leads to a reduction of arable land productivity and a decrease in nationwide yield production. Especially, salinization is the case in the plain irrigated areas of Uzbekistan where the groundwater is closer to the surface. Salinization processes occur as a result of an increase in the level of groundwater and the degree of their mineralization due to inefficient and irrational use of water and land resources in Uzbekistan. This leads to a decrease in the productivity of irrigated land and a decrease in yields throughout the country. Principally, salinization takes place in irrigated plain areas like the Syrdarya province, where mineralized groundwater is closer to the surface. Considering the geo-location of Uzbekistan as an aridic zone, there is a massive stress on groundwater because of surface water shortage. Since the estimation of the salinization consequences on groundwater is critical, this research, therefore, was aimed to understand and evaluate the long-term changing behavior of groundwater level and its mineralization in the irrigated areas of the Syrdarya province of Uzbekistan from 2000 to 2015 by using traditional methods, and GIS-based methods for from 2016 to 2019. The level and mineralization of groundwater in each administrative district of the province were for the first time studied and assessed. Consequently, the dependence of the groundwater level and its mineralization on soil conditions and climatic factors were determined. Based on the results of the study, agricultural specialists and farmers of the province were highly advocated to take the following measures considering the actual condition of groundwater mineralization in the irrigated areas of the Syrdarya province: (1) targeted and economical use of irrigation water; (2) ensuring that existing drainage networks are in an adequate working condition and can operate with full-efficiency; and (3) to conduct annual monitoring of groundwater table and its mineralization of irrigated lands using traditional and GIS technologies.