Three Gorges Dam shrinking Yangtze delta

May 21, 2007

Chinese scientists have determined how China's Three Gorges Dam -- the world's largest dam -- affects downstream sediment delivery in the Yangtze River.

Researchers from East China Normal University found river damming can damage downstream environments by retaining sediments and nutrients.

Shi-Lun Yang and colleagues at the university's State Key Laboratory of Estuarine and Coastal Research calculated supplies of water and sediment from ungauged areas and combined them with data sets from gauging stations.

They discovered the Three Gorges Dam, which has regulated the waters of the Yangtze River since 2003, retains two-thirds of the upstream sediment each year and, in response to that retention, significant erosion occurs in the riverbed downstream of the dam.

Since the erosion doesn't offset the sediment lost in the reservoir, and because sediment flux to the Yangtze River mouth has decreased by 31 percent per year, the Yangtze delta is shrinking.

The researchers said continued sediment retention at those rates, combined with more dams planned for the watershed, will severely affect the people and various ecosystems in the Yangtze delta.

The study appears in the journal Geophysical Research Letters.

Copyright 2007 by United Press International

Explore further: New, tighter timeline confirms ancient volcanism aligned with dinosaurs' extinction

add to favorites email to friend print save as pdf

Related Stories

People finding their 'waze' to once-hidden streets

12 hours ago

When the people whose houses hug the narrow warren of streets paralleling the busiest urban freeway in America began to see bumper-to-bumper traffic crawling by their homes a year or so ago, they were baffled.

Identity theft victims face months of hassle

12 hours ago

As soon as Mark Kim found out his personal information was compromised in a data breach at Target last year, the 36-year-old tech worker signed up for the retailer's free credit monitoring offer so he would ...

Observers slam 'lackluster' Lima climate deal

12 hours ago

A carbon-curbing deal struck in Lima on Sunday was a watered-down compromise where national intransigence threatened the goal of a pact to save Earth's climate system, green groups said.

Your info has been hacked. Now what do you do?

12 hours ago

Criminals stole personal information from tens of millions of Americans in data breaches this past year. Of those affected, one in three may become victims of identity theft, according to research firm Javelin. ...

New Bond script stolen in Sony hack

13 hours ago

An "early version" of the screenplay for the new James Bond film was the latest victim of a massive hacking attack on Sony Pictures Entertainment, its producers said in a statement on their website Sunday.

Ag-tech could change how the world eats

18 hours ago

Investors and entrepreneurs behind some of the world's newest industries have started to put their money and tech talents into farming - the world's oldest industry - with an audacious agenda: to make sure there is enough ...

Recommended for you

Scientists make strides in tsunami warning since 2004

11 hours ago

The 2004 tsunami led to greater global cooperation and improved techniques for detecting waves that could reach faraway shores, even though scientists still cannot predict when an earthquake will strike.

Trade winds ventilate the tropical oceans

11 hours ago

Long-term observations indicate that the oxygen minimum zones in the tropical oceans have expanded in recent decades. The reason is still unknown. Now scientists at the GEOMAR Helmholtz Centre for Ocean Research ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.