Application of GIS technologies in the investigation of soil salinity

Abstract

Soil salinization is the major problem affecting the productivity of irrigated lands. In Uzbekistan, irrigated area amounts to 4.5 million hectares or about 10% of Uzbekistan's total area and almost 46.6% of these lands are affected by increasing salinity. The main reason for these conditions of irrigated land is the effect caused by natural factors (primary salinity) - inefficient natural drainage, saline groundwater, high evapotranspiration rates, and high capillary capacity of the soil. Moreover, human-induced processes (so-called "secondary salinity"), which lead to the enrichment of mineralization of groundwater. The objectives of this study iarethe soil salinity monitoring of irrigated lands and the mapping of the temporal and spatial distribution of salt-affected soils for the Arnasay district of Jizzakh province in Uzbekistan to support land management. Field data collected in 2017- 2018 was analyzed and based on the analysis soil map was developed. In the research area, based on these maps changes in soil salinity were identified. The results indicate that inefficient irrigation activities in the region would affect to the enrichment of salts in the top soils and reduce soil productivity. The GIS technologies are efficient tools for monitoring salt-affected lands.