Process–form linkages in meander morphodynamics

Abstract

Meandering rivers are one of the most dynamic earth-surface systems. They play an important role in terrestrial-sediment fluxes, landscape evolution, and the dynamics of riverine ecosystems. Meandering rivers have been of fundamental interest to researchers across a wide range of disciplines, from fluvial geomorphology to fluid mechanics, from river engineering to landscape ecology, owing to the intriguing complexity of meander morphodynamics. This interest also comes from the socio-economic concerns due to the river hazards caused by bank erosion, channel change, and flooding, as well as the adverse responses of meandering rivers to human- and climate-induced changes in the environmental conditions. An in-depth, process-based understanding of the dynamics of meandering river–floodplain systems is critical in order to investigate the responses of these systems to the changes in environmental conditions. Over the last few decades, there have been significant advances in river meandering research, with contributions from both theoretical modeling and experimental and field-based research. This paper presents a detailed overview of river meandering research, particularly focusing on the advances in the process-based understanding of meander morphodynamics. It also discusses the standing challenges in addressing the dynamics of real meandering rivers and their floodplain patterns and processes, and potential future directions in river meandering research. The paper advocates the crucial need for bridging theoretical modeling with field- and laboratory-based research in order to inform accurate assessments of river-hazard risks and facilitate ecologically sound river-management and restoration practices with the aim of supporting healthy ecosystems.