Dr Manijeh Ghahroudi Tali, Sir Farhad Khodamoradi, Dr Khadijeh Alinoori,
Volume 11, Issue 4 (2-2025)
Abstract
Subsidence as an environmental hazard is caused by various natural and human factors. The drastic changes in land use, the increase in the number of deep wells, and the effects of the subsidence phenomenon in Dehgolan plain show the need to investigate these influencing factors. In such a situation, adequate understanding of the degree of vulnerability and investigation of the influencing factors in that process provides the opportunity for planning and environmental preparation of the space in order to reduce vulnerability. In this research, first, the NDVI index of the plain was investigated with the help of 15 Sentinel-2 and Landsat 8 satellite images, and the best date was selected for the Sentinel-1 images. In this way, 8 Sentinel-1 satellite images were analyzed over a period of 8 years (2014-2021) and all the images were analyzed and processed in eight stages with the help of SNAP software. 3 Landsat 7 and 8 satellite images were used to investigate land use changes (2000-2021).By applying atmospheric and radiometric corrections and finally performing the supervised classification method using Arc GIS software, land use was extracted and its changes were checked. The interferometric results showed that the Dehgolan plain suffered a total of 480 mm of subsidence. So that 60 mm of subsidence has occurred in this plain every year. In the end, with the preparation of the map of land use changes, the classes of irrigated agricultural and residential lands increased by 6.98, 1.47 percent, and the uses of pasture, forest and rainfed lands were faced with a sharp decrease, so that irrigated lands increased by 8477 and residential by 672 hectares. Is. The results obtained from the analysis of the relationship between water use and subsidence showed that rapid subsidence occurs mainly in water and urban land use classes. This is a consequence of increasing water extraction for agriculture and drinking. Usually, the pattern of land use conversion with more human influences has increased the rate of subsidence.
