The morphodynamic responses to deposition-promoting projects in island and reef coasts of the Zhoushan Archipelago, China  

作　　者：Qingzhi Hou Zhili Wang Yongjun Lu Siping Mo 

机构地区：[1]State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing 210029, China

出　　处：《International Journal of Sediment Research》2017年第3期351-363,共13页国际泥沙研究（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Grant Nos.51520105014 and 51379127);National Key R&D Plan(2017YFC1404204)

摘　　要：China’s island and reef coasts are mainly distributed along the coasts of Zhejiang and Fujian provinces.These areas have favorable deep-water conditions and great development potential. The Zhoushan Archipelago is a typical island and reef coast. In the midst of the islands, there are many tidal channels with high water depth and high current velocity. Daishan Island is located on the northern part of the Zhoushan Archipelago. The sea north of Daishan Island can be characterized as having great water depth(generally between 10 and 20 m), high current velocity(the maximum measured value is about 2 m/s),and hyperconcentrated suspended sediment(annual average concentration under normal weather conditions is about 0.6 kg/m~3). Sediment transport is influenced by the co-action of waves and currents.Land reclamation can ease the contradiction between the desire for development and the land resource shortage on island and reef coasts. Land reclamation generally starts from deposition-promoting projects on island and reef coasts with hyperconcentration of suspended sediment with the aim of reducing the reclamation cost. Based on the morphodynamic characteristics of the sea area near north of Daishan Island, a two-dimensional mathematical model was developed to analyze the co-action of current and waves and the model was verified for spring as well as neap tides in 2007 and 2012. The simulated values of tidal stages, tidal current velocities, tidal current directions, and suspended sediment concentration at15 stations in 2007 and 9 stations in 2012 were in good agreement with the in-situ measured values.Furthermore, the simulated magnitude and pattern of erosion and sedimentation agreed well with the observations. This model was used to evaluate the effects of a proposed siltation scheme on the hydrodynamic environment and morphological change of the study area. The results of this study can inform the protection, development, and utilization of shoal-channels on island and reef coasts, as well provide a scientific basiChina's island and reef coasts are mainly distributed along the coasts of Zhejiang and Fujian provinces.These areas have favorable deep-water conditions and great development potential. The Zhoushan Archipelago is a typical island and reef coast. In the midst of the islands, there are many tidal channels with high water depth and high current velocity. Daishan Island is located on the northern part of the Zhoushan Archipelago. The sea north of Daishan Island can be characterized as having great water depth(generally between 10 and 20 m), high current velocity(the maximum measured value is about 2 m/s),and hyperconcentrated suspended sediment(annual average concentration under normal weather conditions is about 0.6 kg/m^3). Sediment transport is influenced by the co-action of waves and currents.Land reclamation can ease the contradiction between the desire for development and the land resource shortage on island and reef coasts. Land reclamation generally starts from deposition-promoting projects on island and reef coasts with hyperconcentration of suspended sediment with the aim of reducing the reclamation cost. Based on the morphodynamic characteristics of the sea area near north of Daishan Island, a two-dimensional mathematical model was developed to analyze the co-action of current and waves and the model was verified for spring as well as neap tides in 2007 and 2012. The simulated values of tidal stages, tidal current velocities, tidal current directions, and suspended sediment concentration at15 stations in 2007 and 9 stations in 2012 were in good agreement with the in-situ measured values.Furthermore, the simulated magnitude and pattern of erosion and sedimentation agreed well with the observations. This model was used to evaluate the effects of a proposed siltation scheme on the hydrodynamic environment and morphological change of the study area. The results of this study can inform the protection, development, and utilization of shoal-channels on island and reef coasts, as well provide a scientific basis

关 键 词：Tidal current WAVE SEDIMENTATION Numerical simulation Island and reef coasts Deposition-promoting projects 

分 类 号：P75[天文地球—海洋科学]