基于组合可拓综合分析法的鄱阳湖流域水质富营养化评价

长期跟踪定位评价湖泊的水质营养化程度，对于实现地区水功能具有重要意义。针对评价方法中指标选取的可行性、单一性、权重赋值的主观随意性以及水质变化的模糊性、随机性、动态性和生物指示性等特点，采用了可拓综合评价法和浮游生物调查与室内测定法相结合，构建了组合可拓综合分析法，一方面利用可拓综合分析法对鄱阳湖流域5个代表性观测站点的10年的年均（每2年）观测数据进行评价；另一方面通过浮游生物指示法对该5个站点的水质进行富营养化评价，以生物指示评价法所得等级与可拓综合分析法评定等级吻合的最多次数所对应等级作为组合可拓综合评价法的评价等级。结果表明：（1）自2006年以来鄱阳湖流域水体富营养化水平较为平稳，总体呈好转势态。2010年有4个观测点的水体达到富营养化程度，而在2014年湖区的蛤蟆石和鄱阳水质略有所改善，达到轻富营养化程度，都昌、康山、星子站点的水体为中营养化，改善幅度较大，水质较好；（2）从湖区的地理区位看，鄱阳湖湖区的南部和西部的水质富营养化程度总体上要好于北部、东部和中部湖区，水质富营养化程度表现为区域的不均匀性。

Eutrophication assessment of water quality in poyang lake basin based on comprehensive analysis method of combined extension

Long-term tracking, positioning and evaluating lake eutrophication are key for water areas to achieve their due functions. Given the feasibility, monotony and subjectivity of weight assignment of index selection assignment in the evaluation method and fuzziness, randomness, dynamic and biological indicative of water quality change, this study combines extensive and comprehensive evaluation with investigation and indoor plankton measurements to construct comprehensive analysis method of combined extension. First, annual data from five representative observation stations in the Poyang Lake Basin were collected for five times (regularly once in two years during 10 consecutive years). The data were evaluated by the combined extension method, whereby the water quality eutrophication of the five sites is evaluated through the plankton indicator method. The maximum consistence of combined level obtained by two methods, i.e. biological indicator evaluation method and extension comprehensive analysis method, can be used as assessing grade for the combined method adopted in the study. The results show that:(1)Water eutrophication has been kept in a stable way and taken on positive changes in Poyang Lake since 2006. In 2010, the water of four observation sites reached the extent of eutrophication. However, in 2014,Toad stone and Poyang sites'' water was improved to light-extented eutrophication; the water of Duchang, Kangshan, Xingzi reached the medium nutrition with improved water quality; (2)In terms of geographic location, the degree of eutrophication of the southern and western areas is better than that in the northern, eastern and central lake regions on the whole, indicating the heterogeneity of eutrophication across regions.