Indices Based Approach Appraisal of Anthropogenic Activities and its Impacts on Stream Power of a Plateau Origin River in India

Anthropogenic activities are one of the extrinsic factors that significantly alter the fluvial processes. The stream power is the primary agent of a river that controls the natural processes of a channel. It is influenced by hydrology, natural configuration and artificial constructions of a river. The Damodar River runs through the plateau, plateau fringe and plain region of eastern India has been selected for the study. It is altered by several anthropogenic activities such as dam and barrage constructions, sand mining, industries and coal mining, landuse changes etc. The upper and middle sections (~180 km) of the river have been taken for the study as stream power variation is significant in these sections. The flow velocity is measured from eleven sites from the upper and middle sections of the river to estimate stream power. The Integrated Anthropogenic Index (IAI) has been generated for the identification of the natural and anthropogenic dominant reaches. The IAI includes various types of indices such as artificial water surface ratio (AWSR), road along river ratio (RARR), road density (RD), artificial river ratio (ARR), artificial coal mining ratio (ACMR), and bridge along river ratio (BARR). The anthropogenic controlled reaches are characterised by the drastic increase of stream power with some exceptional knicks. The multimodal stream power distribution of the river is associated with energy alteration. It reflects in the development of various types of bars which are inversely related to stream power. Innumerable human activities produce slope irregularities resulting in stream power and eventually, it reflects on the processes and landform development of the river.