, 2008) In South Asia, more than 80% of water and sediment disch

, 2008). In South Asia, more than 80% of water and sediment discharges from the Indus River have been diverted by large reservoirs and flow diversion (Giosan et al., 2006). In the Red River basin, the HoaBinh

dam constructed in 1989 is estimated to be responsible for the 50% decline in annual sediment delivery to the delta (Dang et al., 2010). During the four years (2003–2006) after Three Gorges Dam impoundment, ∼60% of sediment entering the Three Gorges Reservoir was trapped. The Manwan Reservoir in the upper reaches trapped substantial amount http://www.selleckchem.com/products/dinaciclib-sch727965.html of Mekong’s sediment since most of its sediment derives from its upper reaches. The sediment load at Gajiu station, located 2 km downstream from the reservoir, is only one-third of the pre-dam level (Wang et al., 2011). In comparison with other world’s large dams, the Xiaolangdi dam not only regulates river flow, but also manages the river’s sediment. The WSM through Xiaolangdi see more dam has temporally mitigated the infilling

of sediment in reservoirs and scoured the riverbed. New problems, however, has arisen that the Xiaolangdi reservoir is losing its impoundment capacity at high rate and the riverbed scouring in the lower reaches has weakened since 2006. The managed WSM therefore may not be a long-term solution for sediment-laden rivers that are troubled by sediment-associated problems. The discharge regime of the Huanghe has deviated greatly from its natural condition due to the multiple dam effects. The dam-triggered changes in Huanghe water and sediment delivery to the sea have caused a series of environmental problems. These problems include a shrinking delta plain due to sediment-starvation, altered ecological environments new and nutrient concentrations in coastal waters, and a transition in plume processes at the river mouth (Chu et al., 2006, Wang et al., 2010 and Yu et al., 2013). The Huanghe delta plain has been shrinking, in response to the curtailed sediment supply (Chu et al., 2006). Many deltas in the world are also shrinking due to dam-triggered sediment reduction

(Chu et al., 2006 and Nageswara Rao et al., 2012). The drowning of the Mississippi delta is ascribed primarily to insufficient sediment supply (Blum and Roberts, 2009), which is largely due to construction of dams in the Mississippi Basin. And the current sediment flux is incapable to sustain the delta plain, even if the diversion plan of the Mississippi River could be performed (Kim et al., 2009 and Allison and Meselhe, 2010). Dams on the Colorado and Nile River, together with extensive downstream irrigation systems, have resulted in almost total elimination of riverine sediment delivery to the coastal regions. As a result, the Colorado and Nile deltas are actively receding due to sediment deficit (Stanley, 1996 and Carriquiry et al., 2001). In the Yangtze basin, the construction of the Three Gorges Dam has been linked to erosion of the Yangtze’s subaqueous delta.

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