English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

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 trib- utaries of Changjiang, sediment deposition induced by the TGD in 2003-2008 was quantified. Furthermore, we deter- mined the theoretical trapping efficiency of the cascade reser- voir upstream of the TGD. Its impact on Changjiang sedi- ment 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 trap- ping efficiency of 75%. Most of the total sediment depo- sition, as induced by the TGD (88%), accumulated within the region between the TGD site and Cuntan. However, sig- nificant siltation (12% of the total sediment deposition) also occurred upstream of Cuntan as a consequence of the up- stream 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 opera- tion, 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 wa- ters are expected.

Sedimentation in the Three Gorges Dam and the future trend of Changjiang (Yangtze River) sediment flux to the sea