Contribution to Book
Revisiting the Morphological Approach : Opportunities and Challenges with Repeat High-Resolution Topography
Gravel-Bed Rivers : Process and Disasters
(2017)
Abstract
Recent technological developments in geodesy, surveying and remote sensing present new opportunities to quantify the rate and distribution of fluvial processes in gravel bed rivers. The objective of this chapter is to critically review the application of established and emerging, repeat, High Resolution Topography (HRT) datasets to support this process and, in particular, the application of the inverse morphological approach to estimate bed material transport. Following a review of the physical basis of the morphological method, we illustrate a workflow to quantify the storage terms of a channel sediment budget based on Digital Elevation Model (DEM) differencing techniques. Two basic applications of the morphological approach are discussed. The first relies on sediment budgeting principles and the net change in storage terms that DEM differencing provides. The second application is based on the erosion estimates from DEM differencing and some estimate of particle path lengths. We emphasize how DEM uncertainty analysis can be used to support robust topographic change detection even in fluvial environments that are characterised by complex morphologies and low amplitude bed level changes. Using a case study data from a labile braided channel, we demonstrate how high resolution DEMs of Difference (DoD) can be used to both determine minimum bed material transport rates from sediment budgeting in the absence of a reference flux, or estimating transport rates by inferring sediment path lengths from the characteric length scales of erosional units.
Disciplines
Publication Date
2017
Editor
Daizo Tsutsumi and Jonathan B. Laronne
Publisher
John Wiley & Sons
ISBN
9781118971406
DOI
https://doi.org/10.1002/9781118971437.ch5
Citation Information
Vericat, D., Wheaton, JM and Brasington, J. 2017. Revisiting the morphological approach: opportunities and challenges with repeat high-resolution topography. Pages 121-158 in Gravel-Bed Rivers: process and disasters ed. D. Tsutsumi & J.B. Laronne. John Wiley & Sons.