From Cropland to Dust Source: Land Use Dynamics and Water Management in the Tigris-Euphrates River Basin

This study examines the relationship between agricultural practices, land abandonment, and the generation of dust storms in the transboundary Tigris and Euphrates River Basin (TERB) from 2000 to 2021.

Problem Statement: Dust storms have emerged as a significant concern in the Middle East, driven by both droughts and anthropogenic activities, particularly in the context of land and water management. These dust storms inflict damage on infrastructure, diminish agricultural productivity, and pose considerable health risks within transboundary river basins. The objective of this study is to identify the underlying drivers of dust storm source generation, with a specific emphasis on the impact of farming patterns and land abandonment following the cropping season.

Methodology: The research integrates spatio-temporal maps that depict land susceptibility to dust storms with agricultural land-use change maps. For this, satellite data from the Moderate Resolution Imaging Spectroradiometer (MODIS) were utilized to identify sources of dust storms. Additionally, machine learning algorithms were employed, incorporating hydrological, topographical, and climatic variables to create dust storm susceptibility maps. Land use and land cover (LULC) data were categorized into bare ground, single cropping, double cropping, and other vegetative types. The study subsequently analyzed the correlations between dust storm sources, land susceptibility, and LULC, focusing on how agricultural practices and land abandonment contribute to the generation of dust storm sources.

Results and Discussion: The analysis indicated a significant correlation between highly susceptible land and an increase in bare ground. The majority of identified dust sources were located on bare ground. Areas designated for single cropping exhibited a higher susceptibility to dust storms compared to those allocated for double cropping. The findings also revealed that annual rainfall has a substantial impact on the percentage of bare ground and the prevalence of dust sources, often with a delay of one year. For example, increased rainfall in 2018 resulted in a decrease in bare ground and dust sources in 2019, while reduced rainfall in 2020 contributed to an increase in bare ground and dust sources in 2021. Although land abandonment following cropping demonstrated a significant potential for dust storm source generation, the conversion of bare ground to cropland effectively lowered dust storm susceptibility, suggesting an inverse relationship between cropping intensity and land vulnerability to dust storms. The results further illustrated that lands that alternate between cropping and fallow periods or are abandoned after cropping are more prone to wind erosion and dust generation.

Conclusion: This study underscores that climate variability and human activities, particularly agricultural practices and land abandonment, are the principal factors influencing dust storm source generation in the TERB. The research emphasizes the critical importance of maintaining year-round vegetation cover, particularly in double cropping systems, as a means of mitigating dust storms. The conclusion drawn from this study advocates for the implementation of sustainable land and water management practices to reduce vulnerability to dust storms, and it calls for further research to explore transboundary water and land management strategies aimed at mitigating the impacts of dust storms.