Large wood and river morphodynamics

Abstract

Large wood is recognised as a key component of river systems that affects river morphology and dynamics. However, the precise influence of large wood varies with properties of the wood (size, form, density, ability to sprout) and properties of the river system with which the wood is associated (size, planform, bed material). In the last decade, there has been an enormous expansion in research on the properties, dynamics and impacts of wood in rivers, and several exciting new perspectives have been proposed. This paper reviews the history of river wood research and then synthesises concepts that have arisen within the last decade to consider how large wood functions as a geomorphic agent. Research needs to extend beyond generalised considerations of the fluvial geomorphic role of large wood and to focus more on the tree species that generate the wood.