University of Tehran Journal of Range and Watershed Managment 5044-2008 77 3 2024 10 22 Land Subsidence Hazard Assessment using Weights-of-Evidence model (Case Study: Karaj City) Land Subsidence Hazard Assessment using Weights-of-Evidence model (Case Study: Karaj City) 389 402 99385 10.22059/jrwm.2024.22623.0 FA Somayeh Taheri Graduate Faculty of Environment, University of Tehran, Tehran, Iran 0009-0001-9100-9945 Hasan Ahmadi Department of Rehabilitation of Arid and Mountainous Regions, Faculty of Natural Resources, University of Tehran, Karaj, Iran Jamal Ghodousi Soil Conservation and Watershed Management Research Institute, Tehran, Iran ُSadat Feiznia Department of Rehabilitation of Arid and Mountainous Regions, Faculty of Natural Resources, University of Tehran, Karaj, Iran Shahram Khalighi Sigaroudi Department of Rehabilitation of Arid and Mountainous Regions, Faculty of Natural Resources, University of Tehran, Karaj, Iran Mohamad Hossein Ramesht Faculty of Geographical Sciences and Planning, Isfahan University, Isfahan, Iran Journal Article 2018 12 13 subsidence in urban areas poses significant risks to infrastructure, including buildings, roads, railways, pipelines, sewage systems, and wells. Therefore, assessing its potential is crucial. This study models the subsidence risk in Karaj city using Geographic Information Systems (GIS) and the Weight of Evidence (WoE) model. To achieve this, we created maps of factors influencing subsidence, such as slope, alluvial thickness, groundwater fluctuations, aquifer layering, particle size, and permeability. These maps were then compared with recorded subsidence data to determine the weight of each factor's influence. By integrating the effects of these factors, a Subsidence Index (SI) map was generated and categorized using the Success Rate Curve (SRC), identifying five sensitivity zones from very sensitive to very low sensitivity. The effectiveness of the WoE model was evaluated, revealing that the subsidence sensitivity prediction map covers 93.64% of actual occurrences. Results indicated that aquifer layering positively influences subsidence development, with the highest impact arising from alluvial deposits with good permeability and fine particles. This factor, with a weight of 3.72, demonstrates significant influence among all evaluated parameters. In terms of thickness, the most significant subsidence occurred in alluvial deposits exceeding 200 meters. Areas experiencing groundwater level declines of over half a meter annually markedly contributed to subsidence. Additionally, slopes of less than two degrees were identified as the most susceptible to subsidence. Thus, while many areas in Karaj are relatively safe, the threat is notably higher in the southern and southwestern parts, requiring special attention in urban management. subsidence in urban areas poses significant risks to infrastructure, including buildings, roads, railways, pipelines, sewage systems, and wells. Therefore, assessing its potential is crucial. This study models the subsidence risk in Karaj city using Geographic Information Systems (GIS) and the Weight of Evidence (WoE) model. To achieve this, we created maps of factors influencing subsidence, such as slope, alluvial thickness, groundwater fluctuations, aquifer layering, particle size, and permeability. These maps were then compared with recorded subsidence data to determine the weight of each factor's influence. By integrating the effects of these factors, a Subsidence Index (SI) map was generated and categorized using the Success Rate Curve (SRC), identifying five sensitivity zones from very sensitive to very low sensitivity. The effectiveness of the WoE model was evaluated, revealing that the subsidence sensitivity prediction map covers 93.64% of actual occurrences. Results indicated that aquifer layering positively influences subsidence development, with the highest impact arising from alluvial deposits with good permeability and fine particles. This factor, with a weight of 3.72, demonstrates significant influence among all evaluated parameters. In terms of thickness, the most significant subsidence occurred in alluvial deposits exceeding 200 meters. Areas experiencing groundwater level declines of over half a meter annually markedly contributed to subsidence. Additionally, slopes of less than two degrees were identified as the most susceptible to subsidence. Thus, while many areas in Karaj are relatively safe, the threat is notably higher in the southern and southwestern parts, requiring special attention in urban management. https://jrwm.ut.ac.ir/article_99385_f02710c86787ca9ab036981fdd66ebb5.pdf