The Influence of Trees on Stream Bank Erosion: Evidence from Root-Plate Abutments

Abstract

Stream bank erosion often isolates the root plate of a riparian tree on a pedestal of sediment jutting out from the stream bank. To our knowledge, these root-plate abutments have not been formally described. Apart from being a landform in their own right, abutments are of interest because their morphology integrates the complex effects of trees on bank erosion processes. From measuring seven abutments formed along the Acheron River in southeastern Australia, we conclude the following: (1) Roots from a single tree increase the resistance of impinging banks in a semi-circle centered on the trunk. The abutment has a radius that is always smaller than (usually less than half) the canopy radius. ..