Abstract
Extensive and rapid changes in various ecosystems under the influence of human interventions and climate change determine the need to locate restoration zones. Intensification of wind erosion and dust storms has been considered as one of the effects of climate change in many parts of the world. The wind direction layer is one of the most important layers in the study of the spatial root cause of the wind erosion problem and dust storms, which has been neglected in many studies. This study presented a simple method for constructing the wind direction layer. Using GIS and multi-criteria assessment, the root of the dust problem has been addressed by identifying areas under severe wind erosion. For this purpose, we studied a highly air-polluted area: the downstream of the Hirmand Watershed, situated along the Iran-Afghanistan border. The region's ecological significance stems from its position where three biogeographical regions meet and the presence of the Hamun international wetlands, enhancing the study's importance. Nine causative criteria and two constraint criteria were used to model the potential for wind erosion using the Weighted Linear Combination (WLC) method at a 250 m resolution. The results showed that the dried wetlands are the most sensitive land use to erosion, which is moderate in the east and lowest in the west. Across the entire study area, erosion sensitivity was moderate in the east and lowest in the west. The very high and high erodibility classes covered areas of 51,568.75 and 187,556.25 ha, respectively. The Hamun International Wetlands are the main wind erosion bed, and their water intake depends on the Hirmand River, which originates in Afghanistan. Therefore, wind erosion in Sistan is mostly affected by cross-border factors. Hydrological drought is the source, impacting regions beyond Iran with dust storms, involving Afghanistan and Pakistan. The study's findings help organizations manage soil protection in Sistan regionally and justify cross-border collaboration for stakeholders.