期刊
EARTH SURFACE PROCESSES AND LANDFORMS
卷 28, 期 8, 页码 889-903出版社
WILEY
DOI: 10.1002/esp.1011
关键词
gravel-bed river; morphological budget; DEM; kriging; sediment transfer
This paper compares two approaches used to derive measures of annual sediment transfers within a 1 km long piedmont reach of the gravel-bed River Coquet in Northumberland, northern England. The techniques utilize: (i) channel planform and cross-section surveys based on a theodolite/electronic distance measurement (EDM) survey of 21 monumented channel cross-sections and channel and gravel bar mar-ins; and (ii) theodolite-EDM survey generating a series of x,y,z coordinates, from which digital elevation models (DEMs) of the reach were constructed. Calculating the difference between DEM surfaces provided a measure of volumetric change between surveys carried out during the spring of 1999 and 2000. The permits computation of estimate variances and confidence intervals use of kriging DEM generation and differencing for sediment transfer. Error analysis, validating the DEMs using surveyed cross-sections, indicated a mean error between surveyed and DEM-generated cross-sections of around twice the value of the D-50 of the surface sediment in the reach. Comparison of sediment volumes derived from the two approaches suggests that, compared with the DEM method, monumented cross-sections underestimate the magnitude of volumetric changes that occur within the reach. The cross-section approach relies on a simplistic integration of the volumes, whereas DEM differencing provides an estimate at a resolution under the control of the analyst. Furthermore, the cross-section approach does not permit a reliable estimate of the uncertainty of the volumes calculated. In addition. the DEM methodology based on the morphological unit scale provides ail explicit identification of spatial patterns of erosion and deposition, a feature that cross-section-based approaches may fail to include. Copyright (C) 2003 John Wiley Sons, Ltd.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据