Journal of Geosciences, Earth and Planetary Systems
Gis-Based Prioritisation of Pennar Watershed in Bapatla District: A Combined Morpho-metric and Land Use/Land Cover Approach
Abstract
Sreerama Naik S R, T K Prasad and Jayapal G
Effective watershed prioritisation is essential for sustainable resource management in vulnerable regions. This study presents an integrated multi-criteria assessment to prioritise sub-watersheds within the Pennar basin of Bapatla District, Andhra Pradesh, a semi-arid coastal area facing significant anthropogenic and climatic pressures. The methodology synergistically combines geospatial analysis of quantitative morphometric parameters with qualitative thematic layers of Land Use/Land Cover (LULC), slope, soil, and rainfall. A comprehensive set of linear, areal, and relief parameters, derived from a CartoDEM and analysed in a GIS environment, characterised the inherent geomorphic and hydrological susceptibility of ten sub-watersheds (SW-1 to SW-10).
The analysis uncovered significant heterogeneity, with sub-watersheds like SW-5 and SW-7 showing high drainage density, complex networks, and elevated ruggedness indices, indicating a tendency for rapid runoff and severe soil erosion. These inherent vulnerabilities were then considered within the human-modified landscape; areas with high morphometric risk that coincide with agricultural dominance, erodible soils, and steeper slopes were prioritised for intervention. The resulting prioritisation ranks SW-7 and SW-5 as very high priority, followed by SW-10 and SW-9 as high priority, offering a clear, evidence-based framework for conservation planning. This research illustrates that a holistic approach, combining the static controls of basin morphology with dynamic land-use factors, is essential for identifying critical erosion hotspots and strategically allocating resources for soil and water conservation in developing coastal agro- ecosystems.