Fluvial Geomorphology

Abstract

Fluvial geomorphology explores the dynamic interplay between rivers and their landscapes in the shaping of river channels and drainage networks. Many familiar features of river channels are the outcome, including meandering, an alternation of riffles, pools, and runs, and the floodplain. These features are formed by the river through cycles of erosion and deposition that in turn are strongly influenced by the balance between the twin supplies of water and sediments. Fluvial geomorphology has many practical applications to river management, informing our understanding of impacts due to altered water or sediment supply, human modifications of the river channel, and changing land use within the catchment. Stream power, the product of discharge and slope, describes the ability of the stream to mobilize and transport material. When sediments are trapped within impoundments or extracted by gravel mining, the sediment-hungry river erodes its banks or its bed until balance is restored, often in the form of an ecologically degraded river. The growing field of river restoration relies heavily on principles of geomorphology to improve the natural state and functioning of river systems in support of ecological and social goals.