Sedimentation in the Three Gorges Dam and the future trend of Changjiang (Yangtze River) sediment flux to the sea
Sedimentation in the Three Gorges Dam and the future trend of Changjiang (Yangtze River) sediment flux to the sea
复制标题
三峡大坝泥沙淤积及未来长江泥沙入海通量趋势
DOI：
10.5194/hess-13-2253-2009
复制
发表时间：
2009-11
影响因子：
6.3
通讯作者：
胡邦琦
中科院分区：
文献类型：
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作者：
杨作升;王厚杰;胡邦琦
抽象的。长江上游的三峡大坝中国扰乱了长江向下游和沿海地区输沙的连续性。根据长江干流和主要支流54年的年水沙资料，量化了2003-2008年长江干流和主要支流由TGD引起的泥沙淤积。此外，还确定了TGD上游梯级水库的理论捕集效率。讨论了它对未来几十年长江泥沙通量的影响。结果表明，2003-2008年TGD每年截留泥沙约1.72亿吨，平均截沙效率为75%。TGD引起的大部分泥沙淤积(88%)积累在TGD场地和寸滩之间的区域。然而，由于TGD上游扩大了回水区，寸滩上游也发生了显著的泥沙淤积(占总泥沙淤积量的12%)。此外，长江泥沙通量在2001年进入了第三个下降阶段，也就是TGD投入使用之前。这主要是由于20世纪90年代末以来金沙江支流泥沙减少所致。随着梯级水库的全面投入使用，它有可能截留金沙江输沙总量的91%，因此，金沙江输沙量很可能在未来几十年内进一步减少到14Mt/年。因此，长江入海泥沙通量在不久的将来将继续减少到90Mt/年以下，仅为20世纪50年代观测值的18%。在低输沙量的情况下，预计将对河口、三角洲和沿海水域的形态产生深远的影响。
Abstract. The Three Gorges Dam (TGD) on the upper Changjiang (Yangtze River), China, disrupts the continuity of Changjiang sediment delivery to downstream and coastal areas. In this study, which was based on 54 years of annual water and sediment data from the mainstream and major tributaries of Changjiang, sediment deposition induced by the TGD in 2003–2008 was quantified. Furthermore, we determined the theoretical trapping efficiency of the cascade reservoir upstream of the TGD. Its impact on Changjiang sediment flux in the coming decades is discussed. Results show that about 172 million tons (Mt) of sediment was trapped annually by the TGD in 2003–2008, with an averaged trapping efficiency of 75%. Most of the total sediment deposition, as induced by the TGD (88%), accumulated within the region between the TGD site and Cuntan. However, significant siltation (12% of the total sediment deposition) also occurred upstream of Cuntan as a consequence of the upstream extended backwater region of the TGD. Additionally, the Changjiang sediment flux entered a third downward step in 2001, prior to operation of the TGD. This mainly resulted from sediment reduction in the Jinshajiang tributary since the late 1990s. As the cascade reservoir is put into full operation, it could potentially trap 91% of the Jinshajiang sediment discharge and, therefore, the Jinshajiang sediment discharge would most likely further decrease to 14 Mt/yr in the coming decades. Consequently, the Changjiang sediment flux to the sea is expected to continuously decrease to below 90 Mt/yr in the near future, or only 18% of the amount observed in the 1950s. In the presence of low sediment discharge, profound impacts on the morphology of estuary, delta and coastal waters are expected.
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DOI：
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发表时间：
2003
期刊：
Yangtze River
影响因子：
--
作者：
Hu Yan
通讯作者：
Hu Yan
DOI：
--
发表时间：
2002
期刊：
China Three Gorges Construction
影响因子：
--
作者：
H. Yue
通讯作者：
H. Yue
影响因子：
6.4
作者：
Qiang Zhang;Qiang Zhang;Chong-yu Xu;V. Singh;Tao Yang
通讯作者：
Qiang Zhang;Qiang Zhang;Chong-yu Xu;V. Singh;Tao Yang
影响因子：
56.9
作者：
G. Shen;Zongqiang Xie
通讯作者：
G. Shen;Zongqiang Xie
DOI：
10.1029/tr034i003p00407
发表时间：
1953-06
期刊：
Eos, Transactions American Geophysical Union
影响因子：
--
作者：
G. Brune
通讯作者：
G. Brune