Decadal changes in sediment budget and morphology in the tidal reach of the Yangtze River
Decadal changes in sediment budget and morphology in the tidal reach of the Yangtze River
复制标题
长江潮汐河段泥沙收支和形态的年代际变化
DOI：
10.1016/j.catena.2019.104438
复制
发表时间：
2020-05
期刊：
影响因子：
6.2
通讯作者：
Jian Sun
中科院分区：
文献类型：
--
作者：
Bing Yuan;Binliang Lin;Jian Sun
在过去的几十年里，流向沿海地区的河流泥沙通量在全球范围内一直在减少。从河流到海洋的泥沙通量通常是根据河流中最低的无潮汐测站来估算的，例如长江。关于潮汐河段十年泥沙收支和形态演变的知识仍然有限。利用长江感潮河段的历史测深资料，研究了1970年至2008年三个时期长江感潮河段的泥沙收支和局部地貌的变化。从输沙通量来看，第I期1970-1992年是一个相对稳定的时期，第II期1992-2003年是一个泥沙通量显著减少的衰退期，第III期2003-2008年是三峡大坝截流后的一个衰退期。河段在第I期基本处于平衡状态，在1992-2003年和2003-2008年期间，河段都发生了净侵蚀，年侵蚀量分别约为6500万吨/年和3700万吨/年。河段年侵蚀对下游河段年泥沙通量的贡献率从1992-2003年的16.9%左右增加到2003-2008年的19.1%。泥沙收支的这些变化与TGD截流后输入泥沙通量的减少、泥沙粒度的粗化以及河水通量和潮汐条件的变化密切相关。局部沉积/冲刷形态复杂，其长度尺度为4-32千米，与局部地形、水深和水流条件的复杂性有关。在1992-2008年期间，河段海平面的水平位置变化有限，这可能是由于人为干预造成了固定的河岸。
In the last few decades, riverine sediment flux to the coastal zones has been decreasing globally. The sediment flux from rivers to seas is usually estimated based on the lowermost gauging stations free of tides in the rivers, for example the Yangtze River. Knowledge of decadal sediment budget and the morphological evolution in the tidal reach is still limited. Here, using historical bathymetry of the tidal reach of the Yangtze, the changes in the sediment budget and local morphology in this reach for three periods between 1970 and 2008 were investigated. In terms of input sediment flux, Period I 1970–1992 is a relatively steady period, Period II 1992–2003 is a decline period with a significant decrease in the sediment flux, and Period III 2003–2008 is a decline period after the closure of the Three Gorges Dam (TGD). The reach was nearly in equilibrium during Period I. Net erosion occurred in the reach during both the pre- and post-TGD decline periods 1992–2003 and 2003–2008, with annual erosion of approximately 65 and 37 Mt/yr, respectively. The contribution of the annual erosion in the reach to the annual sediment flux at the downstream end of the reach increased from around 16.9% during 1992–2003 to 19.1% during 2003–2008. These changes in the sediment budget are closely related to the decrease in the input sediment flux, coarsening of the sediment grain size after the closure of the TGD, and changes in the riverine water flux and tidal conditions. Characterized by a length scale of 4–32 km, local deposition/erosion patterns were quite complex, which relates to the complexity of the local geometry, bathymetry and flow condition. The horizontal location of the thalweg of the reach had limited changes during 1992–2008, likely owing to the fixed riverbank due to human intervention.
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DOI：
10.1029/01eo00219
发表时间：
2001-08
期刊：
Eos, Transactions American Geophysical Union
影响因子：
--
作者：
A. Murray
通讯作者：
A. Murray
影响因子：
3.9
作者：
Brunier, Guillaume;Anthony, Edward J.;Dussouillez, Philippe
通讯作者：
Dussouillez, Philippe
三峡大坝下游长江流域的河流流量和泥沙负荷发生了怎样的变化？
影响因子：
6.4
作者：
Guo Leicheng;Su Ni;Zhu Chunyan;He Qing
通讯作者：
He Qing
DOI：
--
发表时间：
1998-11
期刊：
--
影响因子：
--
作者：
D. Knighton
通讯作者：
D. Knighton
影响因子：
18.3
作者：
Syvitski, James P. M.;Kettner, Albert J.;Nicholls, Robert J.
通讯作者：
Nicholls, Robert J.