贵州三岔河水质时空分布特征与评价

Temporal-spatial distribution pattern and evaluation of water quality in Sancha River

目的了解贵州三岔河水质的时空分布特征。方法分别于2014年枯水期(2月22—27日)和丰水期(8月17—23日),选取三岔河26个采样点,在丰、枯水期对河流溶解氧、氨氮等6项指标进行监测,探讨水质的季节变化特征和空间差异,并分别采用单因子水质标识指数法、单因子评价法、综合水质标识指数法和改良模糊标识指数法对三岔河水质进行分析及评价。结果三岔河上游水质优于中、下游,枯水期水质污染较丰水期严重,其主要污染物为总氮,其次为化学需氧量和总磷,呈现富营养化状态。相比于其他评价方法,改良模糊标识指数法比较适于三岔河水质的评价。枯水期各采样点水质主要以Ⅴ类水为主,而丰水期水质主要以Ⅱ类和Ⅲ类水为主。结论应关注三岔河枯水期的水质污染。

Objective To understand temporal-spatial distribution pattern and to do evaluation of water quality in Sancha River.Methods Water samples from 26 sampling points of Sancha Rivers were sampled in dry season and wet season,and were analyzed for water quality in 2014,and the characteristics of water quality according to the seasonal shifts and the spatial differences were explored, the degree of contamination of water bodies were assessed by using different water quality assessment. Results Sancha River water quality had obvious spatial and temporal distribution characteristics,and the main contaminant were nitrogen,followed by the COD and the total phosphorus,all of these showed that the river was contaminated by water eutrophication. The modified fuzzy identification index evaluation showed that,the water quality in dry season mainly was in the class Ⅴ and in wet season it mainly was in class Ⅱ or Ⅲ. Conclusion In the investigated reach of Sancha River,water contamination is serious in dry season.