Morphometric parameters are the mathematical visualizations of watershed landforms that provide powerful insights into the hydrological processes that drive and shape a watershed. This is especially true for climatically variable regions with complex topographies such as in our study area in the Nablus Mountains. This study aimed to identify the morphometric characteristics of the Nablus Mountains and the spatial distribution of those characteristics. By using the 2008 ALOS PALSAR Digital Elevation Model with a spatial resolution of 12.5 meters for surface and hydrological analysis, eleven main watersheds were recognized and divided into two main drainage systems, i.e. the Mediterranean Sea Drainage System (MSDS) in the west and Dead Sea Drainage System (DSDS) in the east. Morphometric characteristics analyses were performed across linear, areal and relief aspects, resulting in 25 parameters. Drainage density (Dd), bifurcation ratio (Rb), circularity ratio (Rc) and hypsometric analysis (Hs) values were the parameters that most clearly differentiated between western and eastern watersheds. Western watersheds were more elongated in shape, with dense vegetation cover, steep sides and high annual rainfall amounts, and the hypsometric integrals revealed them to be older than those in the east. In contrast, watersheds in the east had high circularity ratio, low vegetation cover and steep slopes, which indicated high susceptibility to flash floods and soil erosion. Thus, soil conservation practices and rainwater harvesting techniques would be better suited for the eastern watersheds and sub-watersheds in the central part of the Nablus Mountains, where slopes are steep and rainfall amounts are high.
Keywords: Morphometric, Hypsometric, ALOS PALSAR , GIS, Semi-arid, .Nablus mountains