Dynamic channel adjustments in the Jingjiang Reach of the Middle Yangtze River.
Dynamic channel adjustments in the Jingjiang Reach of the Middle Yangtze River.
复制标题
长江中游荆江河段航道动态调整
DOI：
10.1038/srep22802
复制
发表时间：
2016-03-11
影响因子：
4.6
通讯作者：
Tan G
中科院分区：
文献类型：
--
作者：
Xia J;Deng S;Lu J;Xu Q;Zong Q;Tan G
长江中游荆江河段因三峡工程的运行而发生了重大的航道调整。研究区域为荆江河段，包括上荆江河段和下荆江河段。从2002年到2013年，每年通过河段平均法计算研究河段的河段尺度平滩河道尺寸，并在171个断面调查洪水后剖面。计算结果表明：UJR和LJR河段尺度岸宽变化较小，岸深分别增加1.6 m和1.0 m;大规模护岸工程的建设导致河道主要在岸深方面发生了调整，但局部地区在没有护岸工程的情况下也出现了明显的岸蚀过程。在UJR和LJR的河段尺度岸堤尺寸一般响应于前五年的平均河流侵蚀强度在汛期，获得更高的相关性的深度和横截面积。它的结论是，这些动态调整的渠道几何形状是一个直接的结果，最近的人类活动，如三峡工程的运作。
Significant channel adjustments have occurred in the Jingjiang Reach of the Middle Yangtze River, because of the operation of the Three Gorges Project (TGP). The Jingjiang Reach is selected as the study area, covering the Upper Jingjiang Reach (UJR) and Lower Jingjiang Reach (LJR). The reach-scale bankfull channel dimensions in the study reach were calculated annually from 2002 to 2013 by means of a reach-averaged approach and surveyed post-flood profiles at 171 sections. We find from the calculated results that: the reach-scale bankfull widths changed slightly in the UJR and LJR, with the corresponding depths increasing by 1.6 m and 1.0 m; the channel adjustments occurred mainly with respect to bankfull depth because of the construction of large-scale bank revetment works, although there were significant bank erosion processes in local regions without the bank protection engineering. The reach-scale bankfull dimensions in the UJR and LJR generally responded to the previous five-year average fluvial erosion intensity during flood seasons, with higher correlations being obtained for the depth and cross-sectional area. It is concluded that these dynamic adjustments of the channel geometry are a direct result of recent human activities such as the TGP operation.