[关键词]
[摘要]
于桥水库作为天津市唯一的饮用水供水水源地, 研究于桥水库周边面源污染对其水质的影响, 有助于改善水 库水环境, 保障供水质量。在分析水库周边面源污染负荷的基础上, 运用基于二维浅水方程和对流扩散方程组构建 的于桥水库二维水动力和水质耦合模拟模型对 2008 年雨季( 6月- 9 月) 水库 T N、 TP 浓度的空间分布及随时间变 化特征进行了模拟分析。结果表明, 受果河入库流量和汛期主导风的影响, 总体上 TN、 T P 随水流主要沿水库南岸 和西北岸向坝前方向扩散, 并在库区东形成顺时针大环流和在库区西形成逆时针环流。受环流影响, 库心水质受污 染影响较小。T P 在空间上呈现出东高西低的趋势, T P 平均浓度最高值出现在 8月份为 1. 56 mg/ L; 刘相营及五百 户镇是 TN 的主要入库口, TN 平均浓度最高值出现在 9 月份为 3. 74 mg/L。
[Key word]
[Abstract]
Yuqiao Reservoir is the unique water source for the water supply of Tianjin City. It. s important to study the effects of the non2point pollution around Yuqiao Reservoir on the water quality in order to improve the water environment and guarantee quality of water supply. Based on the analysis of non2point pollution load, a coupled two2dimensional hydrodynamic and pollutant transport model was developed using the two 2dimensional shallow water and pollutant transport equations. The two 2dimensional model was used to simulate the temporal and spatial distribution characteristics of T N and T P in the reservoir water from June to September in 2008. The simulation results showed that(1)under the effects of inflow of Guo River and dominant wind direc 2 tion in the wet period, T N and TP concentrations diffuse towards the dam site along the south and northwest coastlines, and form the clockwise circumfluence in the east area and the counterclockwise circumfluence in the west area of the reservoir; (2) due to circulation, the water quality in the reservoir center is less affected by the pollution; (3) TP concentration in the east is higher than that in the west of the reservoir, and the average concentration of T P in August is the highest( 1. 56 mg/L); and(4) Liuxiangying and Wubaihu are the main pollution ports of TN, and the average concentration of the T N in September is the highest(3. 74 mg/L).
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[基金项目]
国家自然科学基金( 51179117) ; 天津市应用基础及前沿技术研究计划青年基金项目( 12JCQNJC05200)