Linking hydrology and sediment dynamics of large alluvial rivers to landscape diversity in the Ganga dispersal system, India

Abstract

Discharge and sediment load data for several stations along the Ganga river and its major tributaries in the Western Ganga plains (WGP) for a period of ~30 years have been analysed to understand the hydrological characteristics and sediment dynamics. In terms of hydrology, the rivers are less flood-prone than believed, exceeding bankfull discharges less frequently than the expected 1.5 year return interval. This has been attributed to the rivers of this region occupying incised valleys formed in the Late Quaternary period. Rivers draining the WGP are supply-limited systems compared to those draining the Eastern Ganga plains (EGP) which have been characterised as transport-limited systems. We suggest that such geomorphic diversity as a function of spatial variability in precipitation regime and hinterland geology has existed for at least Late Quaternary period and they in turn influence the modern day hydrology of the river systems in a significant way. This article is protected by copyright. All rights reserved.