30 Transport Capacity, Bedrock Exposure, and Process Domains

摘要

Turowski (Chapter 29, this volume) provides a comprehensive review of the rapidly developing field of bedrock erosion of semi-alluvial channels. He has distilled a large and dense literature, logically organized the subject matter, and identified the salient issues. Providing a guide to the literature with an exhaustive reference list is a service to those who want to understand this problem. The main challenges have been to understand a spectrum of processes and conditions governing bedrock erosion that are difficult to observe, so that models that are consistent with process can be formulated. It has become evident that a dominant control on bedrock erosion is exposure to the tool effects of particles in transport, since rates of wear of bedrock by impacting particles commonly exceed greatly rates of uplift (Sklar and Dietrich, 2001). Thus the attention to semi-alluvial channels is justified for increasing our understanding of drainage network evolution.