强潮海湾水动力环境对人类干预的响应——以泉州湾为例

Hydrodynamic Environment Response to Human Interventions in a Macro Tidal Bay:The Example of the Quanzhou Bay

泉州湾平均潮差大于4.2m,最大潮差超过6m,是典型强潮海湾.泉州湾向东面向台湾海峡开敞,年平均波高0.9m,最大波高2~4m,泥沙运动受波浪和潮流共同作用.针对泉州湾海域波浪、潮流、泥沙以及海床演变特点,建立了二维波流泥沙数学模型,2016年大小潮验证表明,计算潮位、流速、流向、悬沙含量与实测过程吻合良好,计算泥沙冲淤量和分布趋势与实测值接近.在此基础上,研究了不同强度人类干预对泉州湾水动力环境的影响.结果表明,1978年以来的边滩围填使泉州湾入口、石湖秀涂断面、洛阳江进出潮量分别减少约4%、8%和14%;人工岛引起的冲淤主要在工程周边,对泉州湾滩槽稳定格局影响较小.纳潮量是维持海湾滩槽稳定的重要指标之一,海湾开发过程中要尽可能不影响海湾以及入湾河口泄洪纳潮.研究结果可为类似强潮海湾滩槽保护、开发利用等提供借鉴.

Quanzhou Bay,the average and maximum tidal range of which being 4.2 m and more than6 m,is a typical macro tidal bay. Quanzhou Bay opens eastward to Taiwan Strait,average and maximum wave height of the bay is 0.9 m and 2 ~ 4 m,sediment transport is influenced by the co-action of waves and currents. Regarding to hydrodynamics,sediment transport and sea bed evolution characteristics of Quanzhou Bay sea area,a two-dimensional mathematical model was developed to analyze the co-action of currents and waves. The simulated values of tidal stages,tidal current velocities,tidal current directions,and suspended sediment concentration in 2016 were in good agreement with the in-situ measured values. The simulated magnitude and pattern of erosion and sedimentation agreed well with the observations. This model was used to evaluate the effects of human interventions on the hydrodynamic environment of the Quanzhou Bay.Results show that side flat reclamation since 1978 caused tidal prism of Quanzhou Bay,ShihuXiutu section and Luoyangjiang estuary decreased by about 4%,8%,and 14%,respectively.The scouring and silting caused by artificial islands distributed mainly in the surrounding sea areas of the project,indicating a little influence on shoal-channel evolution pattern in Quanzhou Bay. Tidal prism is an important index to maintain the shoal-channel stability for macro tidal bays,great attention should be paid not to affect flood discharging and tidal prism of bay and estuary connecting to the bay when develop in such bays. The results of this study can inform the protection,development,and utilization of shoal-channels on similar macro tidal bays,as well provide a scientific basis for comprehensive maritime protection and development.