【作者】 邓熙；

【导师】 韩博平；

【作者基本信息】 暨南大学 ， 环境科学， 2005， 硕士

【摘要】 流溪河水库是广州市的重要饮用水源地。2001和2002年的水质现状调查显示,流溪河水库营养状态指数(TSI)的平均值为33.8,整体上处于中营养水平,水库湖泊区的水质要好于河流区。本文运用CE-QUAL-W2建立了流溪河水库二维水动力学和水质模型,模型模拟了水位的变化、水温的时间和空间分布以及浮游植物—溶解氧—营养盐之间的动态关系。使用2001年4月至2002年12月的数据对模型进行校正。水位、水温和溶解氧的模型计算值与实测值相吻合。营养盐和浮游植物生物量的模型计算值也基本与实际情况一致。经过校正后的模型能够很好地模拟流溪河水库中水动力学和水质的变化特征。本文运用模型模拟了磷酸盐在水库中从上游到下游的迁移过程。在一场模拟的暴雨事件中,大量的磷酸盐随着流域地表径流进入水库的上游边界,大约经过102小时后,磷酸盐污染带的前锋到达水库的下游边界。同时还模拟了水库中氮、磷输入量的增加对浮游藻类的影响,结果表明流溪河水库中磷是限制性营养盐。此外还模拟了流溪河森林公园中不断增加的游客数量对水库大坝区表层水体的影响。结果显示,磷酸盐对游客数量的增加表现最为敏感,其浓度的平均增幅最大,浮游藻类生物量次之。在入库水量和水库蓄水量均较少的时期,污染物的影响程度要较大。最后还模拟了水库出水口高程的变化对大坝区水体的影响。结果表明,降低出水口的高程可以增加水温分层的深度,另外也可以减小水体厌氧区的范围。更多还原

【Abstract】 Liuxihe Reservoir, a large reservoir located in Guangzhou, is the major water source supplying drinking for Guangzhou city. Based on the investigations from 2001 to 2002, its average trophic state index was 33.8, which indicating a mesotrophic reservoir. For understanding the reservoir hydrodynamics and ecology in deep, a two-dimensional, laterally averaged hydrodynamic and water-quality model, CE-QUAL-W2, was applied to the reservoir. Water level, temperature distribution, dissolved oxygen, algal biomass and nutrient were simulated by the model. The model was calibrated using hydrodynamic and water-quality data obtained from April 2001 to December 2002. The calibration results showed the model was good at simulating the hydrodynamic and water-quality characteristics of Liuxihe Reservoir. Simulated water level, temperature, dissolved oxygen concentration, nutrient concentration and algal biomass were fit well to the measurements. A hypothetical input of phosphate at the upper rivers of Liuxihe Reservoir during a major storm event took nearly 102 hours to disperse over the entire length of the reservoir. Simulations of algal response to increases of nitrogen and phosphorus loads demonstrated that the algal growth was limited by phosphorus in the reservoir. The model was also used to evaluate the effects of increasing tourists in the nearby forest park on the water quality of surface layer within the dam reach. The results showed that both phosphorus concentration and algal biomass increased significantly. The influences of pollutants by tourism were more obvious when both inflow and water level of the reservoir were low. Effects of changes in reservoir outlet elevation on the vertical profiles of water temperature and dissolved oxygen concentration were simulated. The deep outlet could increase the depth of water temperature thermocline. It could also reduce the anaerobic extent of reservoir bottom.更多还原