Suspended Sediment Concentration and Fluxes in the High-Turbidity Zone in the Macro-Tidal Hangzhou Bay
The turbidity maximum zone (TMZ) plays an important role in the morphology and ecosystems of estuaries. The distributions of TMZ in Hangzhou Bay (HZB) and mechanisms of sediment fluxes in TMZ have been studied by applying a fully calibrated three-dimensional baroclinic model that considers salinity,...
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MDPI AG
2023-10-01
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| Series: | Journal of Marine Science and Engineering |
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| Online Access: | https://www.mdpi.com/2077-1312/11/10/2004 |
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| author | Xin Chen Hui Shen Jinxiong Yuan Li Li |
| author_facet | Xin Chen Hui Shen Jinxiong Yuan Li Li |
| author_sort | Xin Chen |
| collection | DOAJ |
| description | The turbidity maximum zone (TMZ) plays an important role in the morphology and ecosystems of estuaries. The distributions of TMZ in Hangzhou Bay (HZB) and mechanisms of sediment fluxes in TMZ have been studied by applying a fully calibrated three-dimensional baroclinic model that considers salinity, high turbidity, sediment flocculation, and density coupling between water and sediment. Based on the method of SSC thresholds, the TMZ is mainly distributed from YG (Yanguan, toponymy in HZB) to ZP (Zhapu, toponymy in HZB). S1 and S2 are the cross-sections within the TMZ. Along the estuary, there is an ascending-to-descending trend observed in the monthly averaged bed current shear stress, while the monthly averaged density displays a descending-to-ascending pattern. The orientation of the monthly averaged surface fluxes of suspended sediment within the TMZ shows a clockwise circular pattern. Moreover, the net flux of suspended sediment along the estuary at section S1 is seaward, while at the section S2, it is landward. The high bottom stress and the sediment fluxes facilitate the retention, deposition, and enrichment of sediment within the TMZ. The suspended sediment fluxes at the two cross-sections was primarily influenced by Eulerian transport, Stokes transport, and tidal pumping transport. At cross-section S1, the sediment transport is dominated by tidal pumping. At cross-section S2, advective transport controls the sediment transportation near the deep northern bank; while near the southern bank of cross-section S2, tidal pumping is still the dominant factor. The outcome of this study provides a foundation for TMZ research in similar macro-tidal turbid estuaries around the world. |
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| issn | 2077-1312 |
| language | English |
| last_indexed | 2024-03-10T21:08:34Z |
| publishDate | 2023-10-01 |
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| series | Journal of Marine Science and Engineering |
| spelling | doaj.art-19d058707397431386a898f56c46eeb22023-11-19T16:59:45ZengMDPI AGJournal of Marine Science and Engineering2077-13122023-10-011110200410.3390/jmse11102004Suspended Sediment Concentration and Fluxes in the High-Turbidity Zone in the Macro-Tidal Hangzhou BayXin Chen0Hui Shen1Jinxiong Yuan2Li Li3Institute of Port, Coastal and Offshore Engineering, Ocean College, Zhejiang University, Zhoushan 316021, ChinaMarine Monitoring and Forecasting Center of Zhejiang Province, Hangzhou 310007, ChinaHangzhou Xi’ao Environmental Sci-Tech Co., Ltd., Hangzhou 310000, ChinaInstitute of Port, Coastal and Offshore Engineering, Ocean College, Zhejiang University, Zhoushan 316021, ChinaThe turbidity maximum zone (TMZ) plays an important role in the morphology and ecosystems of estuaries. The distributions of TMZ in Hangzhou Bay (HZB) and mechanisms of sediment fluxes in TMZ have been studied by applying a fully calibrated three-dimensional baroclinic model that considers salinity, high turbidity, sediment flocculation, and density coupling between water and sediment. Based on the method of SSC thresholds, the TMZ is mainly distributed from YG (Yanguan, toponymy in HZB) to ZP (Zhapu, toponymy in HZB). S1 and S2 are the cross-sections within the TMZ. Along the estuary, there is an ascending-to-descending trend observed in the monthly averaged bed current shear stress, while the monthly averaged density displays a descending-to-ascending pattern. The orientation of the monthly averaged surface fluxes of suspended sediment within the TMZ shows a clockwise circular pattern. Moreover, the net flux of suspended sediment along the estuary at section S1 is seaward, while at the section S2, it is landward. The high bottom stress and the sediment fluxes facilitate the retention, deposition, and enrichment of sediment within the TMZ. The suspended sediment fluxes at the two cross-sections was primarily influenced by Eulerian transport, Stokes transport, and tidal pumping transport. At cross-section S1, the sediment transport is dominated by tidal pumping. At cross-section S2, advective transport controls the sediment transportation near the deep northern bank; while near the southern bank of cross-section S2, tidal pumping is still the dominant factor. The outcome of this study provides a foundation for TMZ research in similar macro-tidal turbid estuaries around the world.https://www.mdpi.com/2077-1312/11/10/2004TMZmacro-tidesSSCsuspended sediment fluxesformation mechanism |
| spellingShingle | Xin Chen Hui Shen Jinxiong Yuan Li Li Suspended Sediment Concentration and Fluxes in the High-Turbidity Zone in the Macro-Tidal Hangzhou Bay Journal of Marine Science and Engineering TMZ macro-tides SSC suspended sediment fluxes formation mechanism |
| title | Suspended Sediment Concentration and Fluxes in the High-Turbidity Zone in the Macro-Tidal Hangzhou Bay |
| title_full | Suspended Sediment Concentration and Fluxes in the High-Turbidity Zone in the Macro-Tidal Hangzhou Bay |
| title_fullStr | Suspended Sediment Concentration and Fluxes in the High-Turbidity Zone in the Macro-Tidal Hangzhou Bay |
| title_full_unstemmed | Suspended Sediment Concentration and Fluxes in the High-Turbidity Zone in the Macro-Tidal Hangzhou Bay |
| title_short | Suspended Sediment Concentration and Fluxes in the High-Turbidity Zone in the Macro-Tidal Hangzhou Bay |
| title_sort | suspended sediment concentration and fluxes in the high turbidity zone in the macro tidal hangzhou bay |
| topic | TMZ macro-tides SSC suspended sediment fluxes formation mechanism |
| url | https://www.mdpi.com/2077-1312/11/10/2004 |
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