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Watersheds from semiarid zones are sensitive to land degradation processes wherein the morphometric investigation is an important aspect to unwrap the susceptible areas. Hence it is a prerequisite for the assessment of erosional pattern of the watershed. Thus, based on the response to erosional processes, prioritization task has been undertaken for fourteen sub-watersheds from basaltic region of Western Ghats of India. A morphometry-based framework using weighted sum analysis (WSA) coupled with the remote sensing data, field data and topographical maps were generated on geographical information system (GIS) platform to estimate the soil erosion susceptibility. The study also evaluates the performance of this new methodology by considering the sediment production rate (SPR) of these sub-watersheds. The resultant WSA-SPR model has prioritized the study area into high, moderate low and very low categories. The high and moderate priority areas lie in the proximity of outlet, upper elevated and undulating terrain of the watershed. It represents 41.38% of the total area covering SW1, 3, 13 and 14 sub-watersheds. This study proposes a useful tool to define areas for planning the strategies to control soil erosion and promote soil conservation. ARTICLE HISTORY

Watersheds from semiarid regions are more sensitive to hydrological processes and sustainability of water resources than humid regions. Hence, it is indispensable to determine the response of watersheds to hydrological processes for water resource management. Thus, the hydrological response-based watershed prioritization study has been undertaken for eight sub-watersheds from semiarid, basaltic region of Western Ghats of India. Intent to this, a novel index has been parameterized using thematic layers such as drainage density, geology, soil, slope, landform classification, land use/land cover, rainfall and runoff (DGSLR). This study evaluates the performance of DGSLR index using three models, namely analytical hierarchy process (AHP), frequency ratio (FR) and fuzzy logic for sub-watershed-wise prioritization. The FR ratio showed the highest value for very high drainage density (8.73) indicating most probability for a high hydrological response. According to AHP weight, most influencing factors to hydrological processes are precipitation (25%), slope (19%) and land use/land cover (14%) followed by landform classification (11%). These three methods are prioritized study area into four classes, i.e., very high, high, moderate and low using area-weighted average method. These models showed that very high-priority area lies near the outlet of the watershed as well as the upper part

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