南四湖典型河流入湖口区水质综合评价

Water Quality Comprehensive Evaluations for The Estuary Areas of Typical Inflow Rivers of Nansi Lake

为了解南四湖13条典型河流入湖口区的水质状况,本研究利用污染分担率值确定评价因子,并应用模糊数学改进层次分析法(IAHP)确定权重,同时求出各水质级别的模糊隶属函数并计算相应的隶属度,最后应用模糊综合评价法对其进行评价。结果表明:河流入湖口区的水质均较差,绝大多数属于Ⅳ类,TP和TN对水质的影响程度较大并远远超出发生富营养化的临界条件。梁济运河和城郭河入湖口区的水质甚至达到了Ⅴ类,泗河和韩庄运河入湖口区的水质较好,属于Ⅲ类,能够达到南水北调东线工程所规划的功能用水的水质要求。与2006至2011年的研究相比,TP、TN的平均含量总体上呈下降趋势,说明近年来南四湖流域环境监管力度成效显著。

In order to evaluate the water quality for the estuary areas of 13 typical inflow rivers of Nansi Lake, the pollution share rates of monitoring indices and improved fuzzy analytic hierarchy processes （IAHP） were employed to determine the evaluation factor and weight respectively, and then the fuzzy membership functions of the water quality levels and the corresponding membership function degrees were calculated. At last, the water quality was evaluated with the method of fuzzy comprehensive evaluation. Results showed that the typical river estuary areas were all found to have a water quality inferiority, and most of them belonged to class IV. TP and TN which had already gone far beyond the eutrophic condition of a lake had a worse impact on the water quality. The water quality for the estuary areas of Liangji River and Chengguo River even reached to class V. Relatively, the estuary areas of Sihe River and Hanzhuang Canal which belonged to class ]]] had a better water quality, and could achieve the planned function water for the east routes of the South North Water Transfer Project. Compared with the research between 2006 and 2011, the average concentration of TP and TN gradually decreased with the approach of the water supply of the South North Water Transfer Project, which indicated the environment supervision of Nansi Lake basin worked well.