Project's information

Project's title Research on the relationship between the dynamical creation of estuary maximum sediment settling in Cam – Nam Trieu estuary and the deposition of sediment in the Hai Phong navigation channel
Project’s code QTFR01.01/20-21
Research hosting institution Institute of Marine Environment and Resources
Coordinating unit, co-chair Institut de recherche pour le développement, France
Project leader’s name Dr.Vu Duy Vinh
Project duration 01/03/2020 - 31/03/2022
Project’s budget 200 million VND
Classify Excellent
Goal and objectives of the project

- Define position and scale of Estuarine Turbidity Maximum (ETMs) in the Cam- Nam Trieu estuary;
- Assess the relationship between the dynamical creation of estuary maximum sediment settling in Cam – Nam Trieu estuary and the deposition of sediment in the Hai Phong navigation channel.

Main results

- Maintain and strengthen cooperation between the parties: coordinate with partners to implement the research contents of the Mission and expand the number of other related cooperation activities. These activities have contributed to strengthening the capacity of researchers studying sedimentary-dynamics processes in coastal estuaries and expanding research cooperation in related research fields.
- The task has determined the cause of the formation of ETMs in the Cam - Nam Trieu estuary associated with fluctuations in salinity. This is the main factor that causes the collection of small suspended sediment particles into larger particles of suspended sediment, forming the ETMs.
- In the Cam-Nam Trieu estuary, there are always two different types of ETMs: 1) the first ETM is formed inside the river with the condition that the salinity in the river is only about 0.1‰, and characterized by turbidity that develops from the bottom to the surface in the ETM; 2) The second ETM is located downstream of the Cam-Nam Trieu estuary, formed with the condition that the salinity in the outer seaward boundary layer is about 15‰, and is characterized by the ETM existing in the lower half of the water column. In the lower half of the water column, while in the upper half, the turbidity is very small.
- The structure of the ETMs in the Cam-Nam Trieu estuary varies significantly with seasons: 1) In the dry season, the maximum turbidity of the ETM in the inner river is much larger than the maximum turbidity in the ETM downstream of the Cam-Nam Trieu estuary; 2) In the rainy season, this trend is reversed, the maximum turbidity occurring in the turbidity area inside the river is much smaller than the maximum turbidity in ETM of the river mouth.
- At the ETMs, the suspended sediment particle size increases sharply, D50 can be above 60.0μm, the deposition rate of suspended sediment particles increases above 0.15mm/s. With the rise of sediment particle size and deposition velocity of suspended sediment, The ETMs are formed along the Cam-Nam Trieu estuary. These ETMs exist all year, with the size, intensity, and location changes according to fluctuations in tidal level and seasonal variation of discharge river. As a result of this phenomenon, sedimentation areas with a high rate of liquid sludge are formed on the channels, ports, and turning basins along the Cam River to the Nam Trieu estuary.

Novelty and actuality and scientific meaningfulness of the results

- Define position and scale of ETMs in the Cam- Nam Trieu estuary;
- Assess the relationship between the dynamical creation of estuary maximum sediment settling in Cam – Nam Trieu estuary and the deposition of sediment in the Hai Phong navigation channel.

Products of the project

- Publications:
4.    Vinh V.D., Ouillon S., 2021. The double structure of the Estuarine Turbidity Maximum in the Cam-Nam Trieu mesotidal tropical estuary, Vietnam, Marine Geology, 442, Article 106670, doi:10.1016/j.margeo.2021.106670
5.    Nguyen, M. H., Ouillon, S., & Vu, D. V. (2021). Seasonal variation of suspended sediment and its relationship with turbidity in Cam - Nam Trieu estuary, Hai Phong (Vietnam). Vietnam Journal of Marine Science and Technology, 21(3). https://doi.org/10.15625/1859-3097/16076
6.    Vinh, V. D., Ouillon, S., & Nguyen, M. H. (2021). Suspended sediment floc size in the Cam - Nam Trieu estuary (Hai Phong, Vietnam), in wet season. Vietnam Journal of Marine Science and Technology, 21(3). https://doi.org/10.15625/1859-3097/16074.
- Other products: Support for 01 PhD student.

Images of project
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