岸线变化对钦州湾水动力环境的影响

【目的】分析岸线变化对钦州湾水动力环境的影响,为钦州湾海岸线开发、海洋环境保护提供科学依据。【方法】结合2004年及2012年海图、卫星影像资料等资料,采用数值模拟的方法对钦州湾2004年—2012年间岸线变化造成潮流、纳潮量、水交换能力的变化进行计算。【结果】岸线变化后,三墩公路顶端附近海域流速增大0.2m/s,犀牛脚附近下降0.1m/s,三墩公路两侧涨潮时潮流流向由东南向变为西南向和正北向;大、小潮期间,海域纳潮量分别下降-1.50×10~8 m~3和-0.29×10~8 m~3,下降幅度分别约为总量的10.3%和10.9%;水体半交换时间由27d延长至28d。【结论】岸线变化对钦州湾水动力环境有一定的影响,岸线开发利用应充分考虑岸线变化对海洋环境的影响。

Effects of Shoreline Change on Hydrodynamic Environment in Qinzhou Bay

Objective]To provide the scientific basis for shoreline development and marine environmental protection,the effects of shoreline change on hydrodynamic environment in Qinzhou Bay were analyzed.Methods]Based on charts and satellite images during the year of 2004 and 2012,the change of tidal current,tidal prism,and water exchange ability of Qinzhou Bay were calculated by numerical simulation method.Results]After the change of the shoreline,the flow velocity of the waters near the top of the Sandun highway was increased by 0.2 m/s,and decreased by 0.1 m / s near the Xiniujiao. The current direction changed from southeast to southwest and north near Sandun in flood tide. The tidal prism of Qinzhou Bay decreased about -1.50×108m3 in spring tidal and about -0.29×108m3 in neap tidal,the decrease amplitude accounted for about 10.3% and 10.9% of total tidal prism respectively. The half exchange time of water was extended from 27 d to 28 d.Conclusion]The shoreline change has a certain effect on hydrodynamic environment in Qinzhou Bay. The coastland development and utilization should fully consider the impact of shoreline changes on marine environment.