双台子河口水环境质量综合评价

Comprehensive Evaluation on the Aquatic Environment in the Shuangtaizi Estuary

以2011年5和8月双台子河口水体pH、溶解氧（DO）、无机氮（DIN）、磷酸盐（P04-P）、COD、石油类和叶绿素α等调查结果为基础，根据各参数表征的意义，筛选并建立了双台子河口水环境质量评价指标体系；运用主成分分析法和层次分析法确定各级指标权重，利用加权综合指数法对双台子河口水环境质量进行了评价。结果表明，2011年5和8月水环境质量综合指数分别为0．48～2．76和0．71～1．50，平均值分别为1．31和1．10。2011年5月的主要污染指标分别为P04-P和8月为DIN、P04-P和COD。双台子河口水环境质量整体超过二类海水水质标准，处于轻污染状态。较高的营养盐和叶绿素α含量预示着该区域存在较高的赤潮发生风险。

An index system and comprehensive evaluation were studied in order to access the water quality of Shuangtaizi Estuary in May and August, 2011. The index system was fixed and stratified primarily based on the representative meaning of every index （pH, dissolved oxygen, dissolved inorganic nitrogen （DIN）, phosphate, COD, oil and Chla etc. ）. The comprehensive evaluation was carried out by the meth-ods of analytical hierarchy process and principal components analysis, results showed that the comprehen-sive indexes ranged from 0.48 to 2.76 in May （averaged at 1.31） and 0. 71 to 1.50 in August （averaged at 1.10）, 2011, which exceeding the second level of the criteria of seawater quality of the P. C. C. and indica-ting a state of mild contamination in the water of Shuangtaizi Estuary. The principal pollutants were phos-phate in May and DIN, phosphate and COD in August, 2011 respectively. The high nutrients and Chla content implied a critical possibility on red tide in the Shuangtaizi Estuary.