中文摘要：

于2008年5月采用D形网半定量采样法调查了连云港市5条河流7个点位的大型底栖无脊椎动物群落多样性，共获得67个大型底栖无脊椎动物分类单元；其中，昆虫纲双翅目18属、蜻蜓目11属；软体动物24种；环节动物4科4属5种。应用典范对应分析（CCA）排序结果将7个样点分成高TN低DO、高电导率和低TN以及高DO和低电导率3组。Shannon—Wiener多样性指数、生物指数和COD水质评价结果表明，多样性指数与生物指数和COD评价结果有较大差异，生物指数和COD评价结果较相似。综合评价结果为青口河的水质属于清洁；蔷薇河、淮沐新河、鲁兰河和新沭河属于轻污至中污。生物指数与TN极显著正相关（r=0．913，P=0．004），多样性指数与TN无相关性（r=0．257，P=0，578）。

英文摘要：

Benthic macroinvertebrates assemblages were collected from 7 sites of 5 Lianyungang rivers in May, 2008. A total of 67 macroinvertebrate taxa were found including 18 genera in Diptera, 11 genera in Odona- ta, 24 species in Mollusca, 5 species and 4 genera in 4 families of Annelida. All sampling sites were plotted out 3 groups by CCA ordination analysis. The water quality was assessed by the Shannon-Wiener diversity index, Biotic Index and COD, the result of diversity index was quite different from those of BI and COD, while the results between BI and COD were similar. Based on above three indicators, the quality of Qianwei river was clean and other rivers were from slight to middle pollution. The Pearson＇s correlation analysis showed that BI corresponded strongly with TN （ r = 0. 913 ,p = 0. 004） and Shannon-Wiener diversity index had no correlation with TN （ r = 0.257, p=0.578）.