【作者】 张显忠；

【导师】 张智；

【作者基本信息】 重庆大学 ， 城市环境与生态工程， 2006， 硕士

【摘要】 水体富营养化是当今人类面临的重大环境课题。我国湖泊由水质污染引起的富营养化问题十分突出,已成为中国经济发展的主要环境问题之一。三峡工程是跨世纪的特大型水利水电枢纽工程,具有防洪、发电、航运以及供水等巨大综合利用效益,也给库区水环境保护提出严峻考验。水库蓄水后,水流速度减缓,大量泥沙沉积,水质变清,透明度增高,春季水温升高、雾日减少,水面日照时间增加,有利于水生植物特别是藻类的光合作用,导致藻类的生长繁殖,增加了三峡库区水体发生富营养化的可能性。因此,开展三峡库区的富营养化问题研究,是实现我国长江流域资源、环境、人口和社会经济可持续发展的迫切需要。本文研究从泥沙对库区水环境影响的角度出发,首先对三峡库区重庆段泥沙的理化特性及冲淤规律进行了分析研究;其次分析了三峡库区泥沙与氮磷的关系,进行了库区泥沙对氮磷的吸附特性试验研究;其后进行了三峡库区重庆段泥沙对硅藻生长影响试验研究;最后结合三峡库区调度规律、库区气候情况、藻类生长条件、泥沙其对水环境的影响,对三峡库区重庆段富营养化的发生潜势及预测方法进行了探讨,得到以下的主要结论:①三峡库区水体的营养盐含量总体来说处于一种较高水平,库区水体含沙量较大,大量实测资料表明泥沙对水体中的污染物和营养盐具有吸附作用,其泥沙对水环境的影响不容忽视。此外,悬浮泥沙颗粒物对藻类生物多样性影响较大,硅藻因具有较硬的外壳,耐摩擦、耐滚动,在三峡库区的藻类种群构成中和数量上占绝对优势,其对水环境也有重要影响。②三峡库区水体中总氮主要由溶解态无机氮组成,含量比较稳定,年变幅不大,库区泥沙对总氮吸附相关性较差。库区水体中总磷主要由颗粒态组成,总磷含量与泥沙含量显著相关,库区泥沙对总磷的吸附相关性显著,但随着水库的调度运行变化较大。泥沙对总磷的吸附量随着时间的增加而递增并逐渐趋于平衡,随着水相中磷初始浓度的增大而增加,但增加程度受泥沙吸附容量的限制而逐渐减缓;单位吸附量随着泥沙粒径的增加而递减。泥沙对水污染物总磷、总氮的吸附均符合Langmuir等温吸附方程拟合,含沙量对磷吸附等温式的参数没有显著影响。③泥沙对磷的吸附,降低了磷的含量,对库区富营养化的发生有控制作用;但泥沙的沉降又增大了水体的透明度,有利于藻类的光合作用,对库区富养化的发生又有促进作用。三峡水库正常蓄水后,水流流态、泥沙含量等将成为浮游藻更多还原

【Abstract】 The water body eutrophication is the significant environmental thesis that human being faces. At present, eutrophication of water bodies is very serious in our country, which is the main environmental problem of limiting economic development.The three gorges project is trans-century big institute of water conservancy and hydroelectric power junction engineering. Although it produces enormous profits in flood control, power generating, shipping and water supply, it produces the water environmental protection is in the crucible of it. The form of the Three Gorges Reservoir would change the flowing rule of current and the flowing rule of sediment in the Yangtze River and its tributaries, the water quality changes clear, the transparency advances, the spring water temperature elevates, the foggy day reduces, the water surface sunshine time increases, it is advantageous to the aquatic plant is specially algae’s photosynthesis, causing the algae the growth reproduction, increased the water body of the Three Gorges Reservoir area to have the eutrophication possibility.Therefore, it is realizes our country resources, the environment, the population and the social economy sustainable development urgent needs that develops the eutrophication question research of the Three Gorges Reservoir area.In this study, the viewpoint that sediment exerts effect on the environment of water body has been considered. First of all, this paper has analyzed and studied on the physicochemical properties and the space-time distributing of sediment in Chongqing section of Three Gorges Reservoir. Secondly, this paper has analyzed the relations of sediment and the nitrogen phosphorus, and the experimental research of the sediment to the nitrogen phosphorus adsorption characteristic. And then, this paper has studied the sediment to diatom’s growth influence in Chongqing section of Three Gorges Reservoir. Finally, this paper discussed the eutrophication trend and the forecast methods in Chongqing section of Three Gorges Reservoir, combining the dispatcher rule and the weather condition and the algae growth condition and the influence of sediment to the water environment, mainly obtained following conclusion:①The study indicated that the nutritious salts is high, and the sediment’s content is higher than the tributaries. Many inspecting data has indicated that sediment can adsorb contamination and nutritious salts in the Three Gorges Reservoir. The effect of sediment to the environment of water body in the Three Gorges Reservoir is not allowed更多还原