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Head cut in stream geomorphology is an erosional feature of some intermittent and perennial streams where an abrupt vertical drop, also known as a knickpoint in the stream bed occurs. The knickpoint, where a head cut begins, can be as small as an overly-steep riffle zone or as a large as a waterfall. When not flowing, the head cut will resemble a very short cliff or bluff. A small plunge pool may be present at the base of the head cut due to the high energy of falling water. As erosion of the knickpoint and the streambed continues, the head cut will migrate upstream.〔Wilcox, J. et al., Feather River Resource Management Group. December 2001. Evaluation of geomorphic restoration techniques applied to fluvial systems. Available from: http://www.feather-rivercrm.org/publications/preports/georest/cover.html. 〕 Groundwater seeps and springs are sometimes found along the face, sides, or base of a head cut.〔North Carolina Division of Water Quality, "Identification Methods for the Origins of Intermittent and Perennial Streams, Version 3.1", February 28, 2005〕 Channel incision is very common when head cuts are involved in stream morphology. In terms of stream restoration, head cuts are one of the most difficult challenges. Installing check dams or elevating the stream by filling the gully are common ways to mitigate up stream migration of the nick point. Another common way to control the knickpoint is by sloping the bank face by laying fabric and rock down. == References == 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Head cut (stream geomorphology)」の詳細全文を読む スポンサード リンク
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