九龙江河口区三维盐度数值计算及分析

Simulation of spatial distribution of salinity in Jiulongjiang Estuary

本文利用ECOMSED模式建立了一个九龙江河口区水动力及盐度的三维数值模型.利用ECOMSED中的物质输运模块,模拟了九龙江河口区的盐度随着潮流运动的变化过程;模型采用河口区丰水期实测水文资料进行验证,计算和分析了河口区水平以及垂直断面的盐度分布情况,分析表明,河口区的盐度分布受潮流运动及九龙江淡水共同作用,有明显的潮周期特征,落潮时在河口区表层以九龙江淡水为主,外海高盐水占据底层区域;而在涨潮时垂向混合较强,表底分层不明显.

A three-dimensional hydrodynamic model for Jiulongjiang Estuary was established with ECOMSED. The result of the model was validated by the observed data from flood season. In order to know the salinity pattern in Jiulongjiang Estuary,we analyzed the salinity output with the model from both the horizontal direction and the vertical section across Haimen Island. The results show that distribution of salinity in Jiulongjiang Estuary is controlled both by the tide and the fresh water from the upstream. During the ebb tide the fresh water dominates the upper layer and the sea water exists at deeper layer. Meanwhile, the water stratification is weak during the flood tide.