In-Situ Observation of Fluid Mud in the North Passage of Yangtze Estuary, China 被引量：1

In-Situ Observation of Fluid Mud in the North Passage of Yangtze Estuary, China

下载PDF

导出

摘要 Observations of fluid mud were made in the lower North Passage of the Yangtze Estuary in February 2000, on 10～11 August 2000, on 30～31 August 2000 (after two strong typhoons), on 21～24 August 2000 (neap tide) and on 3～6 September 2000 (mean tide) respectively. In situ data show that the fluid mud in this area consists of fine cohesive sediment (median size 7.23 μm). The formation and movement of fluid mud varied during the neap-spring and flood-ebb tidal cycle. Observations suggest that fluid mud phenomena in this area may be categorised in a three-fold manner as slack water, storm and saltwedge features. The thickness of the fluid mud layer of slack water during the neap tide ranged from 0.2 to 0.96 m, whereas during the mean tide, the thickness ranged from 0.17 to 0.73 m, and the thickness of the fluid mud layer was larger during slack water than at the flood peak. Shoals cover an area of 800 km2 with a water depth smaller than 5 m. Erosion of these extensive intertidal mudflats due to storm action provides an abundant sediment source. This is particularly significant in this estuary when the tidal level is lower than 5 m. The lower North Passage is a typical zone of saltwater wedging, so the saltwedge fluid mud has the most extensive spatial range in the estuary. Observations of fluid mud were made in the lower North Passage of the Yangtze Estuary in February 2000, on 10～11 August 2000, on 30～31 August 2000 (after two strong typhoons), on 21～24 August 2000 (neap tide) and on 3～6 September 2000 (mean tide) respectively. In situ data show that the fluid mud in this area consists of fine cohesive sediment (median size 7.23 μm). The formation and movement of fluid mud varied during the neap-spring and flood-ebb tidal cycle. Observations suggest that fluid mud phenomena in this area may be categorised in a three-fold manner as slack water, storm and saltwedge features. The thickness of the fluid mud layer of slack water during the neap tide ranged from 0.2 to 0.96 m, whereas during the mean tide, the thickness ranged from 0.17 to 0.73 m, and the thickness of the fluid mud layer was larger during slack water than at the flood peak. Shoals cover an area of 800 km2 with a water depth smaller than 5 m. Erosion of these extensive intertidal mudflats due to storm action provides an abundant sediment source. This is particularly significant in this estuary when the tidal level is lower than 5 m. The lower North Passage is a typical zone of saltwater wedging, so the saltwedge fluid mud has the most extensive spatial range in the estuary.

作者李九发万新宁何青应铭时连强 S.M. Hutchinso

机构地区 State Key Laboratory for Estuarine and Coastal Research Telford Institute of Environmental Systems

出处《海洋工程：英文版》 2004年第1期149-156,共8页 China Ocean Engineering

基金 ThisworkwassupportedbytheNationalNaturalScienceFoundationofChina (GrantNo .5 0 1790 12 )

关键词 fluid mud in situ observations north passage Yangtze Estuary China fluid mud in situ observations north passage Yangtze Estuary China

分类号 P343.5 [天文地球—水文科学]

引文网络
相关文献

参考文献13

1Cormor, B A and Nicholson, J, 1988. Mud transport modelling, Physical Processes in Estuaries, New York, Springer-Verlag, 532 - 543.
2Gu, W H, 1986. Effect of typhoon on the sedimentation in Tongsha dredged channel in Changjiang Estuary, Marine Science Bulletin, 10( 1 ) : 60 - 62. (in Chinese).
3Guan, X W and Chen, Y Z, 1992. In situ micro-observation of the sediment flocs in the Changjiang Estuary, Journal of Sediment Research, (3): 54-59. (in Chinese).
4Holle, C. G., 1952. Sedimentation at the mouth of the Mississippi River, Conference on Coasted Engineering, 2:111 - 129.
5Kirby, R, 1988. High concentration suspension (fluid mud) layers in estuaries, Physical Processes in Estuaries, New York, Springer-Verlag, 463 - 487.
6Li, J F, He, Q and Xiang, W H et al, 2001. Fluid mud transportation at water wedge in the Changjiang Estuary, Science in China (B), 44, 47 - 56.
7Li, J F and Zhang, Ch, 1999. Sediment resuspension and implications for turbidity maximum in the Changjiang Estuary, Marine Geology, 148, 117- 124.
8Odd, N V M , 1988. Mathematical modelling of mud transport in estuaries, Physical Processes in Estuaries, New York, Spfinger-Verlag, 503 - 531.
9Odd, N V M and Owen, M W, 1972. A two layer model of mud transport in the Thames Estuary, Proc Inst Civil Eng, London, Supp. 9: 175.
10Puls, W, Kuehl, H and Heymann, K , 1988. Settling velocity of mud flocs: Results of field measurements in the Elbe and Weser Estuaries, Physical Processes in Estuaries, New York, Springer-Verlag, 404-426.