فهرست نشریات علمی دسترسی آزاد ایران

The construction of large dams in regions with temperate climates and dense forest cover causes significant land use changes that require precise assessment and continuous monitoring. To prevent the worsening of crises related to vegetation degradation and the loss of natural resources, the cumulative impacts of dam construction must be evaluated over time using a hydro-ecological approach. This study investigates land use and vegetation cover changes in the Meyjaran Dam basin over 30 years. Satellite imagery from Landsat 5 and Sentinel-2B was employed to assess the pre- and post-construction periods. Land use changes were analyzed in two spatial extents: a small study area (464 ha) and a larger watershed (4,027 ha) that includes the study area and the upstream dense forest cover. Image classification was performed using supervised classification with the Maximum Likelihood algorithm, achieving a Kappa coefficient of 0.99. Spatial change analysis was conducted using the Location Quotient (LQ) index. The results indicated that within the small study area, forest cover declined by 84.22 ha (18.14%), while built-up areas increased by 25.25 ha, and rangelands and agricultural lands grew by 24.19 ha. In the larger watershed, forest cover decreased by 120.80 ha (3%). These findings highlight the extensive ecological impacts of dam construction on forest ecosystems beyond the immediate inundation zone.