Impact of seasonal tide variation on saltwater intrusion in the Changjiang River estuary

Qiu, Cheng; Zhu, Jianrong; Gu, Yu

doi:10.1007/s00343-012-1115-x

Cited by 34 publications

(17 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…According to the results derived from this study, there were high positive correlations between the net landward salt fluxes and the tidal ranges. This finding is also consistent with previous studies (Qiu et al 2012;Han et al 2014). The tidal range can be used as an important indicator of saltwater intrusion in Qiantang Estuary.…”

Section: Implications For Society and Environmental Policysupporting

confidence: 94%

Detecting the mechanisms of longitudinal salt transport during spring tides in Qiantang Estuary

Gao

Pan

et al. 2019

Journal of Integrative Environmental Sciences

View full text Add to dashboard Cite

Saltwater intrusion has immediate influences on the water resources utilization, aquatic environment and ecological system. Hence, it is essential to detect the mechanisms of salt transport. This study adopted observations including instantaneous flow velocities, tide levels and salinity during 10 tide cycles at 2 stations in upstream and downstream of Qiantang Estuary in China. The variables of instantaneous flow velocity and salinity were decomposed into the timeaverage, time-varying and vertical-varying components using the flux decomposition model. Then, the salt flux components attributed to various physical processes were quantified. During spring tides, the longitudinal salt transport is controlled by advection transport and tidal pumping transport in the upper river reaches, while being mainly controlled by advection transport in the lower river reaches. The net water flow fluxes and salt fluxes are landward in the lower river reaches. However, the transport direction of the salt fluxes is inconsistent with that of the net water flow fluxes in the upper river reaches, where the net water flow fluxes are mainly seaward while the net salt fluxes are mainly landward. In general, there are significant positive correlations between the net landward salt flux and the tidal range. Thus, the tidal range can be used as an important indicator for determining the required amount of freshwater to be discharged from the reservoir in order to resist saltwater intrusion. The vertical distribution of salt in Qiantang Estuary is relatively uniform. The vertical shear force has limited influence on the salt transport. The research results are expected to supply a reference to future research on other macrotide estuaries. ARTICLE HISTORY

show abstract

Section: Implications For Society and Environmental Policysupporting

confidence: 94%

Detecting the mechanisms of longitudinal salt transport during spring tides in Qiantang Estuary

Gao

Pan

et al. 2019

Journal of Integrative Environmental Sciences

View full text Add to dashboard Cite

show abstract

“…The fortnightly spring tide generates a greater saltwater intrusion than the neap tide does. The saltwater intrusion is also enhanced by the seasonal variability of tides, with the maximum tidal range in March [8,25]. Saltwater Intrusion in the Changjiang Estuary http://dx.doi.org/10.5772/intechopen.80903…”

Section: Impact Of Tidementioning

confidence: 99%

“…Saltwater intrusion in the Changjiang Estuary is controlled mainly by the river discharge and tide [2,[5][6][7][8], but is also influenced by wind [4], topography [9], river watershed and estuary projects [10][11][12], and sea level rise [13]. The natural evolution and artificial reclamation of the intertidal zone from the 1950s to the 2000s have severely narrowed the upper reaches of the NB [14].…”

Section: Introductionmentioning

confidence: 99%

Saltwater Intrusion in the Changjiang Estuary

Zhu¹,

Wu²,

Li³

et al. 2018

Coastal Environment, Disaster, and Infrastructure - A Case Study of China's Coastline

Self Cite

View full text Add to dashboard Cite

Saltwater intrusion in the Changjiang Estuary and the impacts of river discharge, tide, wind, sea level rise, river basin, and major estuary projects on saltwater intrusion are studied in this chapter. There is a net landward flow in the NB (North Branch) when river discharge is low during spring tide, resulting in a type of saltwater intrusion known as the SSO (saltwater-spilling-over from the NB into the SB (South Branch)), which is the most striking characteristic of saltwater intrusion in the estuary. A three-dimension numerical model with HSIMT-TVD advection scheme was developed to study the hydrodynamic processes and saltwater intrusion in the Changjiang Estuary. Saltwater intrusion in the estuary is controlled mainly by river discharge and tide, but is also influenced by wind, sea level rise, river basin, and estuary projects. Saltwater intrusion is enhanced when river discharge decreases. There is more time for the reservoir to take freshwater from the river when river discharge is larger. The fortnightly spring tide generates greater saltwater intrusion than the neap tide. The saltwater intrusion in the SP (South Passage) is stronger than that in the NP (North Passage), and the intrusion in the NP is stronger than that in the NC (North Channel). The northerly wind produces southward currents along the Subei coast as well as the landward Ekman transport, which enhances the saltwater intrusion in the NC and NB and weakens the saltwater intrusion in the NP and SP. Saltwater intrusion becomes stronger as the sea level rises and is much stronger when river discharge is much small. The DWP (Deep Waterway Project) alleviates the saltwater intrusion in the NC and the lower reaches of the NP and enhances the saltwater intrusion in the SP and in the upper reaches of the NP. The Three Gorges Dam (TGD) increases river discharge in winter, which weakens saltwater intrusion, and is favorable for reducing the burden of freshwater supplement in the highly populated estuarine region. The Water Diversion South to the North Project (WDP) decreases river discharge, enhances saltwater intrusion, and is unfavorable for freshwater supply in the estuary.

show abstract

“…Considerable numerical modeling of the Yangtze River Estuary (YRE) has been carried out in recent years, most of which were focused on the hydrodynamics, such as salt water intrusion [e.g., Qiu et al ., ; Xue et al ., ], transport time [e.g., Wang et al ., ; Li et al ., ], and storm surges [e.g., Hu et al ., ]; little involved suspended sediment transport processes. On the other hand, most previous studies of the suspended sediment transport and the ETMs in the YRE have been based on field work [e.g., Su and Wang , ; Shen et al ., ; Shi et al ., ; Li and Zhang , ; Chen et al ., ; Shi et al ., ; Wu et al ., ; Gao et al ., ; Liu et al ., ; Wu et al ., ; Jiang et al ., ].…”

Section: Introductionmentioning

confidence: 99%

Suspended sediment transport in the Deepwater Navigation Channel, Yangtze River Estuary, China, in the dry season 2009: 2. Numerical simulations

Song

Wang

2013

J. Geophys. Res. Oceans

View full text Add to dashboard Cite

[1] A three-dimensional wave-current-sediment coupled numerical model with wetting and drying process is developed to understand hydrodynamics and sediment transport dynamics in the Deepwater Navigation Channel (DNC), the North Passage of the Yangtze River Estuary (YRE), China. The model results are in good agreement with observed data, and statistics show good model skill scores and correlation coefficients. The model well reproduces the spring-neap variation between a well-mixed estuary and a highly stratified estuary. Model results indicate that the estuarine gravitational circulation plays the most important role in the estuarine turbidity maximum (ETM) formation in the DNC. The upstream nonlocal sediment intrusion through the spillover mechanism is a major source of sediment trapping in the North Passage after the morphological changes. Numerical studies are conducted to show scenarios in the YRE under the effects of different forcings (river discharges, waves, and winds). Between these study cases, surface-wave-breaking relieves the sediment trapping and bottomwave-current-interaction aggravates the bed erosion and elevates the SSC in the ETM; the former and the latter have the least and largest influence on the suspended sediment transport in the DNC. The wind effects have a greater influence on sediment trapping than the river discharges, and the steady northwesterly wind condition favors the siltation in the DNC most. The significance of density-driven turbidity current is also assessed, which can enhance the saline-water intrusion and suppress the turbulent mixing in the bottom boundary layer.

show abstract

Impact of seasonal tide variation on saltwater intrusion in the Changjiang River estuary

Cited by 34 publications

References 6 publications

Detecting the mechanisms of longitudinal salt transport during spring tides in Qiantang Estuary

Detecting the mechanisms of longitudinal salt transport during spring tides in Qiantang Estuary

Saltwater Intrusion in the Changjiang Estuary

Suspended sediment transport in the Deepwater Navigation Channel, Yangtze River Estuary, China, in the dry season 2009: 2. Numerical simulations

Contact Info

Product

Resources

About