Bank Erosion as a Desirable Attribute of Rivers

[ "Joan L. Florsheim (e-mail: ) are with the Department of Geology at the University of California at Davis."]; [ "Jeffrey F. Mount are with the Department of Geology at the University of California at Davis."]; [ "Anne Chin is with the Department of Geography at Texas A&M University in College Station."]
BioScience (Impact Factor: 5.44). 05/2008; DOI: 10.1641/B580608

ABSTRACT Bank erosion is integral to the functioning of river ecosystems. It is a geomorphic process that promotes riparian vegetation succession and creates dynamic habitats crucial for aquatic and riparian plants and animals. River managers and policymakers, however, generally regard bank erosion as a process to be halted or minimized in order to create landscape and economic stability. Here, we recognize bank erosion as a desirable attribute of rivers. Recent advances in our understanding of bank erosion processes and of associated ecological functions, as well as of the effects and failure of channel bank infrastructure for erosion control, suggest that alternatives to current management approaches are greatly needed. In this article, we develop a conceptual framework for alternatives that address bank erosion issues. The alternatives conserve riparian linkages at appropriate temporal and spatial scales, consider integral relationships between physical bank processes and ecological functions, and avoid secondary and cumulative effects that lead to the progressive channelization of rivers. By linking geomorphologic processes with ecological functions, we address the significance of channel bank erosion in sustainable river and watershed management.

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