|
Read Full Article (file size: 2085052 bytes) Cited by
WATER RESOURCES RESEARCH,
VOL. 42,
W04407,
doi:10.1029/2005WR003970,
2006
Dam impacts on the Changjiang (Yangtze) River sediment discharge to the sea: The past 55 years and after the Three Gorges
Dam
Z. Yang
College of Marine Geosciences, Ocean University of China, Qingdao, China Key Laboratory of Seafloor Science and Exploration Technology, Ocean University of China, Qingdao, China
H. Wang
College of Marine Geosciences, Ocean University of China, Qingdao, China Key Laboratory of Seafloor Science and Exploration Technology, Ocean University of China, Qingdao, China
Y. Saito
Institute of Advanced Industrial Science and Technology, Geological Survey of Japan, Tsukuba, Japan
J. D. Milliman
Virginia Institute of Marine Science, Gloucester Point, Virginia, USA
K. Xu
Virginia Institute of Marine Science, Gloucester Point, Virginia, USA
S. Qiao
College of Marine Geosciences, Ocean University of China, Qingdao, China Key Laboratory of Seafloor Science and Exploration Technology, Ocean University of China, Qingdao, China
G. Shi
Changjiang Water Resource Commission, Wuhan, China
Abstract
In 5 recent years (2000–2004), the Changjiang (Yangtze) River has discharged past Datong (600 km from the river mouth) an
average of ∼250 million tons (mt) of sediment per year, a decrease of more than 40% since the 1950s and 1960s, whereas water
discharge at Datong has increased slightly. Water and sediment discharge data from the upper, middle, and lower reaches of
the river suggest that the reduction of the Changjiang sediment load has occurred in two phases between 1950 and 2002: following
the closure of the Danjiangkou Reservoir on the Hanjiang tributary in 1968 and following the installation of numerous dams
and water-soil conservation works in the Jialingjijang catchment after 1985. As the Three Gorges Dam (TGD) started operating
in 2003, the Changjiang entered a third phase of sediment reduction with annual sediment loads at Datong less than 200 mt/yr.
Upon completion of the Three Gorges Dam (TGD) in 2009, the sediment load at Datong will decrease to ∼210 mt/yr for the first
20 years, then will recover to ∼230 mt/yr during 2030–2060, and will reach ∼310 mt/yr during 2060–2110. From the sediment
budget and sediment erosion data for the Changjiang subaqueous delta, it can be assumed that the delta will be eroded extensively
during the first five decades after TGD operation and then will approach a balance during the next five decades as sediment
discharging from TGD again increases.
Received 18
January
2005;
accepted 9
November
2005;
published 15
April
2006.
Keywords: Changjiang (Yangtze) River;
dam impacts;
deltaic erosion;
phasic change;
sediment discharge;
TGD.
Index Terms: 1808 Hydrology: Dams; 1834 Hydrology: Human impacts; 1862 Hydrology: Sediment transport (4558); 3022 Marine Geology and Geophysics: Marine sediments: processes and transport.
Read Full Article (file size: 2085052 bytes) Cited by
Citation: Yang, Z., H. Wang, Y. Saito, J. D. Milliman, K. Xu, S. Qiao, and G. Shi
(2006),
Dam impacts on the Changjiang (Yangtze) River sediment discharge to the sea: The past 55 years and after the Three Gorges
Dam,
Water Resour. Res.,
42,
W04407,
doi:10.1029/2005WR003970.
Copyright 2006 by the American Geophysical Union.
|