Behaviour of fine suspended sediment at the North passage of the Changjiang Estuary, China

The change of water split ratio has important impacts on the fluvial process, saltwater intrusion and navigation in estuary area. A 2D hydrodynamics numerical model of the Changjiang Estuary was set up using Delft3D-FLOW. The calculation results are consistent well with the real measured data, which indicates that the model can be used in hydrodynamic analysis. Simulation results show that the ebb water split ratio of the North Branch in the flood season is larger than that in the dry season, while the situation of the South Branch is opposite. Under the condition of different tidal types, the ebb water split ratio for the North Branch is maximum during the spring tide, and minimum during the neap tide, while the one during the middle tide takes the second place.

Download Full-text

Notice of Retraction: Numerical Analysis on Riverbed Erosion and Sediment Deposition in the North Branch of the Changjiang Estuary

2011 5th International Conference on Bioinformatics and Biomedical Engineering ◽

10.1109/icbbe.2011.5780747 ◽

2011 ◽

Author(s):

Jie Gu ◽

Wei Chen ◽

Wenting Li ◽

Xin Qin ◽

Danqing Ma

Keyword(s):

Numerical Analysis ◽

Changjiang Estuary ◽

Sediment Deposition ◽

The Changjiang Estuary ◽

The North

Download Full-text

Impacts of the Qingcaosha Reservoir on saltwater intrusion in the Changjiang Estuary

Anthropocene Coasts ◽

10.1139/anc-2020-0015 ◽

2021 ◽

Vol 4 (1) ◽

pp. 17-35

Author(s):

Zhangliang Ding ◽

Jianrong Zhu ◽

Hanghang Lyu

Keyword(s):

Saltwater Intrusion ◽

Neap Tide ◽

Spring Tide ◽

Changjiang Estuary ◽

Water Diversion ◽

The Changjiang Estuary ◽

The North ◽

Salinity Increase ◽

Hydrodynamic Processes ◽

Changxing Island

The massive Qingcaosha Reservoir (QCSR) is located in the Changjiang Estuary along the northwest coast of Changxing Island. The reservoir significantly narrowed the upper reaches of the North Channel and deepened the channel near the reservoir. These topographical changes inevitably influenced hydrodynamic processes and saltwater intrusion in the estuary. A well-validated model was employed to investigate the influence of the QCSR on saltwater intrusion in the Changjiang Estuary. The model results showed that the narrowed upper reaches of the North Channel decreased the water diversion ratio and thus increased salinity in the North Channel. During the moderate tide after neap tide, the salinity decreased at the water intake of the QCSR because saltwater intrusion was obstructed at flood slack at the surface, while the salinity increase during the moderate tide after spring tide was mainly due to the intensified saltwater intrusion during spring tide. The deepening of the channel near the QCSR resulted in an increased water diversion ratio, and the salinity in the Eastern Chongming Shoal decreased by more than 0.5 psu during spring tide; however, the saltwater intrusion was enhanced due to the strengthened baroclinic force, which is proportional to the water depth. During neap tide, the salinity in the entire North Channel decreased because of a 1.4% increase in the water diversion ratio of the North Channel and the relatively weak tide.

Download Full-text