奥运湖不同补水方案营养状态趋势分析

规划中的奥运湖位于奥林匹克公园，运行中将采用人工补水方式。为保证未来奥运湖的正常景观生态功能，源水经奥运公园中人工湿地处理后再引入湖中。在规划设计阶段，提出三种补水方案：（1）清河再生水厂出水经湿地处理后入湖，（2）清河河水经湿地处理后入湖，（3）经湿地处理达地表水环境标准中的Ⅳ类水要求后入湖。为了考察不同水源补水方案对奥运湖的水质保障程度，本研究对不同方案下奥运公园湖水质的时间、空间变化过程予以模拟，分析评价奥运湖可能出现的富营养化状况，并对各个补水方案带来的富营养化风险和基本成因予以推断，为奥运湖的设计运行提供技术依据。结果表明，方案3的富营养化风险最小、水质保障程度最高。结合三种补水方案水质特点，推断磷是主要限制因子，所以控制磷的浓度是保证水质安全、降低富营养化风险的重要途径。

Nutrition Status Trends Analysis on Different Compensation Water Scenarios for Olympic Lake

The Olympic Lake is located in the north of the Olympic Park,Beijing.During the planning procedure,three(compensation) water alternatives are involved:(1) treated effluent from Qinghe Wastewater Treatment Plant by a wetland in the Park,(2) treated river water from Qinghe River by the wetland,and(3) treated water by the wetland after complying with Category IV of Environmental Standard for Surface Water.In order to assess the environmental impact of three alternatives,the temporal and spatial changes of lake water quality were simulated.And the potential eutrophic states were assessed by different methods.As a result,the third alternative has the lowest eutrophication risk,and the highest water quality guarantee.Based on the assessment,it was found that phosphorus will be the main limiting factor of eutrophication.So for avoiding the eutrophication it is very important to control phosphorus concentration.