Document Type : Research Paper
Authors
1
Department of Surveying Engineering, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University, Tehran, Iran
2
Department of Surveying Engineering, Faculty of Civil, Water and Environmental Engineering , Shahid Beheshti University, Tehran, Iran
10.22034/gp.2026.66924.3395
Abstract
Lake Urmia, the second saltiest lake in the world, has faced a drastic reduction in surface waters and intensified drought over the past two decades. This crisis comes with cross-border environmental impacts. The present study analyzes three key indicators of groundwater change, the SPI, and the VHI using satellite data from Google Earth Engine (Landsat, MODIS, GRACE, TRMM) across two northern regions (Sharfkhaneh and Golonjeh) and two southern regions (Chapghalu and Shirwan Shalyan) for the period 2002–2017. The findings show that the decline in groundwater depth is nearly uniform across all regions. However, the SPI index indicates severe drought in the Sharfkhaneh area (northeast) due to an above-average decrease in precipitation compared with other regions. Additionally, the VHI, calculated as the equal combination of the VCI and TCI, reveals a notable decline in vegetation health by 13 percent in the same region. These results suggest a movement of the watershed feeding the lake toward drought, with the pace of this trend being significantly higher in the north, particularly the northeast. Key factors behind this phenomenon include the depletion and homogenization of groundwater resources, reduced precipitation in the north, and human impacts—especially in the eastern part—such as dam construction, unbridled agricultural expansion, and the drilling of unauthorized wells. These changes threaten the regional ecosystem, local communities’ livelihoods, and agriculture. A more precise examination of these factors could guide effective strategies to reduce drought and maintain ecological balance. It is essential to prioritize the challenges and develop operational actions to improve the environmental conditions and living standards of the region’s residents. These strategies should include sustainable water resource management, a reevaluation of dam projects, and lake ecosystem restoration. Attending to these points will prevent the crisis from worsening and foster the resilience of local communities to climate change.
Keywords
Main Subjects
)