Sumit Das

The river systems in peninsular India are remained unexplored in terms of hydro-geomorphic evolution, though a few works are carried out in order to understand the tectonic and structural evolution with paleoclimate. Morphometric analysis at catchment scale delivers insights into the dynamics, erosion capacity, probability of flood occurrence, lithological and structural control, and genetic response to the tectonics. The present study aimed to characterize the hydro-geomorphic evolution of 12 major catchments in Peninsular India via morphometric analysis. A total 25 morphometric parameters were computed and several statistical analyses performed in establishing the inter-correlation and making classification of Indian rivers. The results indicated that most of the rivers in peninsular India are 7th to 9th order catchments. A high variability of the rainfall was observed in these rivers where the northern catchments experience higher amount of precipitation contrasting to the southern basins. Almost all the basins showed a moderate relief ratio, hypsometric integral, ruggedness etc. Cauvery, Baitarni, and Brahmani showed exceptionally steeper gradient, high relief ratio, LS factor, and ruggedness index which may indicate higher erosion potential. A positive association between erosion rate and hypsometric integral was observed. All these rivers were classified in three categories based on cluster analysis where the medium and large sized catchments formed different groups. Despite of the extensive data and statistical analysis, the outcomes of this study are highly general due to large scale variation in lithology and climate. In foreseeable works dealing with such morphometric variables, a higher resolution sub-catchment scale analysis would be required for a better description of the hydro-geomorphic response of these large catchments in peninsular India.