Soil Salinity Monitoring in Irrigated Areas of Rishtan District of Ferghana Valley, Uzbekistan

Abstract

The salinization of soils impacts many arid areas. In the world, about 62 million hectares of agricultural land are subject to salinization. At present, about 47% of the irrigated lands in Uzbekistan are subject to some degree of salinity. Landsat satellite photos taken across an exact time span (from 1993 to 2021) with timeframes of 8 to 10 years were utilized in this study to monitor soil salinity. To analyze soil salinity level, salinity index, and classification method using Google Earth was performed. During the entire study period, changes in the indicator of soil salinity improvement work were shown. Especially related to non-saline soil, which was around 4,670 ha in 1993, and it increased to 10,533 ha in 2021 and reached 19.2 % after thirty years. Slightly saline soil class has the propensity to decrease and included its largest area of 15,941 ha (52.1 %) in 1993, but then dropped quickly to 9,649 ha (31.5 %) in 2021. Saline soil maximum increased in 2001 to 10.251 ha (33.5 %), then started steadily contracting and reaches a minimum of 7,440 ha (24.3%) in 2011. Strongly saline soil starts reaching from 1,771 ha to 5,069 ha between 1993-2001.