Geomorphic Changes and Sediment Dynamics in Rivers: Causes and Consequences

Abstract

A geomorphic framework defines the mutual linkages between the river forms and the processes within a specific zone in the river. It can therefore provide attributes at different scales that can create a platform to distinguish different geomorphic classes of rivers. In large river systems, the characterization of geomorphic diversity and assessment of geomorphic processes in different geographic regions should therefore be the pre-requisite for designing sustainable river management strategies. Given the importance of rivers as a vital source of freshwater and the ever-increasing demands for the same, there has been a pandemic deterioration of river systems globally, accompanied by serious threats to water security and frequent river related hazards. Human disturbances of different types at different scales in river systems are a consequence of the perceived needs of human populations; however, these needs have to be in consonance with the needs of the river itself and must be planned based on the process-based understanding of rivers. This chapter presents an overview of geomorphic processes in rivers, with special reference to the Himalayan rivers that form the lifeline of a large population in this country. We place special emphasis on sediment dynamics of the Himalayan rivers as this is emerging as one of the most serious challenges in managing these rivers.