2007-2010年新昌江水质趋势分析

Water quality analysis and assessment of surface water at the Downstream of Xinchang River during 2007-2010

目的:分析和评价2007-2010年新昌江下游地表水水质变化趋势,为进一步改善水质提供科学依据。方法:应用内梅罗指数法对新昌江下游地表水主要污染指标进行水质综合评价并进行趋势分析。结果:新昌江下游地表水中总磷、化学需氧量、氨氮和高锰酸钾指数浓度最大值均出现于2007年,分别为0.63mg/L、104mg/L、19.31mg/L、13mg/L,分类等级分别为劣V、劣V、劣V、V,随后逐渐下降,于2009年下半年基本达到III类水质标准,溶解氧浓度2007年的最低值为2.98mg/L,分类等级为V类,随后逐渐升高于2008年下半年达到I-II类水质标准。内梅罗指数逐渐下降至1以下,达到清洁等级。结论:新昌江下游地表水污染状况趋好,主要污染指标逐渐向好,总体水质状况基本好转。

Objective To analyze and evaluate the change trend of water quality of surface water at the downstream of Xinchang River during 2007-- 2010,and to provide scientific basis for the improvement of water quality. Methods Nem- eron pollution index was used to assess the major pollution indexes of the surface water at the Downstream of Xinchang River during 2007--2010. Results The maximum value concentrations of TP （0.63mg/L）, COD （104mg/L）, NH3--N （19.31mg/I.） and CODMn （13mg/L） occurred in 2007,while the minimum value of DO （2.98mg/L） occurred in 2007. The concentrations of TP, COD, NH3--N and CODMn all showed downtrend, while DO showed uptrend steadi- ly. The levels of the five indexes gradually accorded with the third category in the Environmental Quality Standards for Surface Water. The Nemeron pollution index tended to drop under l（clean grade）. Conclusions The major pollution in- dexes were improved, and the water quality of surface water at the＇downstream of Xinchang River turned for the better.