Catastrophic human-induced change in stream-channel planform and geometry in an agricultural watershed, Illinois, USA
Catastrophic human-induced change in stream-channel planform and geometry in an agricultural watershed, Illinois, USA
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DOI：
10.1111/j.1467-8306.2003.09304001.x
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发表时间：
2003-12-01
期刊：
影响因子：
--
通讯作者：
Rhoads, BL
中科院分区：
文献类型：
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作者：
Urban, MA;Rhoads, BL
在全球范围内，渠道化对溪流和河流环境质量的不利影响已有充分的文献记载，但相对于地貌过程的功效，人类引起的河流系统变化的程度尚有待定量确定。溪流渠化是美国中西部农业景观的一个共同特征。这项研究表明，在伊利诺伊州中东部的恩巴拉斯河流域的渠化已经改变了流通道和平面形状的几何形状的程度，超过背景的变化率unchannelized达到一至两个数量级。由于河流对渠化的响应而导致的河道位置的平均变化率也大大超过了非渠化河段的平均变化率，但河流对渠化的调整的空间范围是有限的，大多数拉直或重新定位的河道在渠化后的几十年里一直保持着它们的改变状态。
The adverse effects of channelization on the environmental quality of streams and rivers at a global scale are well documented, but the magnitude of human-induced changes in river systems relative to the efficacy of geomorphological processes has yet to be ascertained quantitatively. Stream channelization is a common feature of the agricultural landscapes of the midwestern United States. This study shows that channelization in the Embarras River basin of east central Illinois has altered stream channel and planform geometries to an extent that exceeds background rates of change for unchannelized reaches by one to two orders of magnitude. The average rate of change in channel position resulting from stream responses to channelization also greatly exceeds the average rate of change for unchannelized reaches, yet the spatial extent of stream adjustments to channelization is limited, and most straightened or relocated channels persist in their altered state for decades following channelization.