【摘要】 为了探明阳澄西湖湖区及其入湖港口的水质现状,为其后续水环境治理提供参考,选取湖区6个位点和4个港口,于2016年5月至2017年3月监测其水质,逢单月月初采样;监测的水质参数包括水深（H）、酸碱度（pH）、溶解氧（DO）、透明度（SD）、悬浮物（TSS）、总氮（TN）、氨氮（NH⁺₄-N）、亚硝酸盐氮（NO^-₂-N）、总磷（TP）、活性磷酸盐（PO■-P）、叶绿素a （Chl-a）、高锰酸盐指数(COD_Mn)、总有机碳（TOC）。运用主成分分析法探讨了水体主要污染因子,采用皮尔逊相关性分析法探究湖区TN、TP对Chl-a浓度的影响。结果显示,阳澄西湖水质综合营养状态指数年均值为57.9,主要水质参数的时空分布表现为枯水期（5-7月）优于丰水期（11-1月）,湖区优于入湖港口,北部优于南部。湖区TN和TP年均值为2.63 mg/L和0.217 mg/L,Chl-a年均值为21.74μg/L,且以9月最低。主成分分析显示,NH⁺₄-N、NO^-₂-N、PO■-P、TP、TN是湖区水质主要的污染因子,TP、NH⁺₄-N、NO^-₂-N、TN是港口水质的主要污染因子。皮尔逊相关性分析显示,阳澄西湖的Chl-a浓度与TN呈正相关（P<0.01）,与TP的相关性不显著（P>0.05）,且相关系数为负值。研究表明,阳澄西湖的Chl-a对营养物质的响应不灵敏,后续治理中需加强对外源氮磷的拦截。更多还原

【Abstract】 Yangcheng Lake has three sections, east, central and west. West Yangcheng Lake is in the upstream area and eutrophication is serious. Since 2009, an algae control program has been in operation to manage eutrophication by releasing filter-feeding fish. In this study, a comprehensive assessment of water quality in west Yangcheng Lake was conducted, including the open area and inlets. The aim of this study was to provide scientific evidence for the evaluation of water environment pollution and algae bloom risk in the west Yangcheng Lake and to guide management of the water environment. Water quality monitoring was carried out at 10 sites（six sites in the open lake and four in the inlets） every two months from May 2016 to March 2017. Water quality parameters analyzed included water depth, pH, dissolved oxygen, transparency, total suspended solids, total nitrogen（TN）, ammonia nitrogen（NH⁺₄-N）, nitrite nitrogen（NO^-₂-N）, total phosphorous（TP）, active phosphorus（PO■-P）, chlorophyll-a（Chl-a）, chemical oxygen demand and total organic carbon. Principal component and Pearson correlation analysis were carried out to identify the primary water quality factors and the relationships among TN, TP and Chl-a. The annual average value of the comprehensive trophic level index was 57.9 in the west Yangcheng Lake. Water quality was better in dry season（May-July） than in wet season（November-January）, better in the open lake than in inlets, and better in the northern area than the southern area. The annual average concentrations of TN and TP were 2.63 mg/L and 0.217 mg/L and the average chl-a concentration was 21.74 μg/L, with the lowest value in September. NH⁺₄-N, NO^-₂-N, PO■-P, TP and TN were the main pollution factors in the open lake and TP, NH⁺₄-N, NO^-₂-N and TN were the main pollution factors in the inlets. There was a significant, positive correlation between Chl-a and TN（P<0.01）, but the correlation of Chl-a with TP was not significant（P>0.05）. These results suggest that Chl-a is not very sensitive to nutrient concentrations in west Yangcheng Lake and that future work should focus on reducing exogenous nitrogen and phosphorus loading of inflowing rivers.更多还原