Soil salinization and desertification dynamics in the cotton-growing regions of Uzbekistan: mitigation approaches
Abstract
This study investigates the interactive dynamics of salinity and desertification in Uzbekistan's cotton basins and evaluates mitigation options to such processes. The findings suggest that the two environmental problems operate in a self-sustaining process: soil salinity increases land vulnerability to wind erosion through the reduction in vegetation cover, and desertification additionally accelerates salt deposit accumulation by accelerating evaporation and reducing permeability. Remote sensing and field observations reveal a worrisome degree of these trends: 68% of the sampling sites exhibit salinity levels above the cotton tolerance (ECe >7 dS/m), and 34% of the regions that cultivate cotton have experienced significant vegetation loss (ΔNDVI < -0.15) over the past eight years (2016-2024). Laboratory tests confirm irreversible changes in strongly deteriorated soils (300% calcium carbonate increase and ESP>25%) and a 50% decline in cotton yield at salinity levels above 12 dS/m. In the analysis of measures, drip irrigation with 42% salt accumulation reduction and 57% increase in water efficiency and halophyte belts with 63% wind erosion reduction were deemed the most effective measures. The composite degradation index placed 6.4% of the area being researched (8,700 ha) in the critical risk category. This research underscores the significance of adopting combined measures such as sustainable water resource management, restoration of adaptive vegetation, and regular monitoring in being key to agroecosystem sustainability.