Characterizing Morphometric Attributes of the Lower Vellar Watershed Using the Geographic Information System, Tamil Nadu, India

Abstract

Morphometric analysis provides invaluable insights into watershed behavior and hydrological processes. This study delves into the morphometric characteristics of the Lower Vellar Watershed, a vital watershed of the Vellar basin in Tamil Nadu, India. Employing geospatial techniques, including remote sensing and geographic information systems (GIS), the study meticulously delineated the watershed boundary and computed a range of linear, areal, and relief parameters. The watershed exhibits a dendritic drainage pattern characterized by five stream orders and 598 streams. Key morphometric indices, such as bifurcation ratio (9.69), drainage density (0.20), and elongation ratio (0.427), were calculated to assess their influence on hydrological processes. The high drainage density indicates a propensity for surface runoff, while the circularity and elongation ratios suggest an elongated basin susceptible to delayed peak flows. Relief parameters, including relief ratio (0.00199) and ruggedness number (24.77), reveal moderate relief features that impact sediment transport and deposition. This study underscores the significance of morphometric analysis as a valuable tool for regional planning and natural resource management, particularly in semi-arid regions like Tamil Nadu. The findings contribute to a comprehensive understanding of watershed behavior, providing a solid foundation for future research and sustainable management strategies for the Lower Vellar Watershed and similar hydrological systems.