大型航道工程建设对海域水环境的影响和风险预测

Prediction of the Impact of Large Scale Channel Engineering on Ocean Water Environment and Associated Risks

以湛江港航道疏浚工程为例,分析工程中水环境污染的主要来源,并对工程施工期和运营期可能对海域水环境的影响进行预测。结果表明:在施工期,工程对水环境的影响主要来源于大型机械的运作,主要污染因子是悬浮物;受岛屿和海岸线的影响,航道前段的悬浮物扩散形态与疏浚中段和末端有所区别,由于主航道与海流流向的夹角很小,悬浮物影响区域主要集中在航道周围。船舶溢油事故以操作性事故为主,占总溢油事故的80%以上,溢油影响范围主要受潮流动力和风况的影响;不同潮期、不同风况下的油膜漂移扩散情况不同,对海域影响的面积和严重程度也不同。

The major sources to cause pollution in a Large scale waterway engineering project are identified.The impact on the ocean water environment during construction period and operating period are simulated and the risks associated are analyzed.The research shows that the pollution of the ocean water environment by the project mainly comes from the operation of large-scale machinery,and the main pollution factor is SS.During dredging operations along the channel,the spread of SS matter in the head section is different from that of the middle section and the rear end for the influence of the islands and shore in the port.Because the angle between main channel and current flow is small,the affected area of SS is mainly confined in the area around the channel.The ship oil spill accident is mainly caused by operation error(more than 80%of total oil spill accidents).The oil spill impact area is basically tidal current and wind condition-dependent,the oil film drift and diffusion are different in different tidal periods and wind conditions,so are the scope and extent of the impact on sea water.