海水作景观水引起河道两岸地下水污染研究

利用天津市滨海新区具有较发达的河网和方便的入海通道，将海水引入河道作景观水是改善水环境的措施之一。该文利用垂向二维变密度水流和溶质运移的数值模型，计算了河道中不同海水水位时两岸地下水的溶质污染扩散趋势和范围，并分析了采取暗管向河道底部两侧含水层注水的工程措施对地下水污染的控制作用。结果表明：河道高水位运行时，海水入侵两岸现象明显；低水位时盐分能控制在一定范围内；对于低水位运行并考虑暗管注水，盐分只向河床底部运移，基本不向两岸扩散。

Research on the groundwater contamination caused by using seawater as lanolscape water in channel coastal

With quite developed river network and convenient channels to the ocean, it is an effective way to use seawater as landscape water to improve water environment in Tianjin beachfront. A two-dimension cross-section numerical model for variable density groundwater and solute transport was adopted to analyze the degree and range of groundwater contamination caused by different seawater levels in the channels. The concealed piping for fresh water injecting moreover. And the control effect of groundwater contamination using the closed drainage for fresh water injecting in the channel bed was discussed. Result shows that salinity diffusion of channel coastal is obvious at high water level, and the salinity diffusion is controled at low water level. At low water level with closed drainage the salinity diffusion only occurs in the channel bed rather than in the channel coastal.