温瑞塘河流域水体污染时空分异特征及污染源识别

不同季节主要污染物的空间分布特征及其潜在的污染源分析对水资源管理与污染控制具有重要意义.本研究应用GIS、主成分分析方法对2008-09~2009-10温瑞塘河水的温度、DO、电导率、p H、浊度、NH+4-N、NO-2、NO-3、PO3-4、Si O2-3、H2S、TOC、TN等水质参数进行时空分异特征分析和潜在污染源的识别.结果表明流域内丰水期、平水期、枯水期的典型污染物是TN、NH+4-N、PO3-4,主要来自于工业和生活点源;空间上水质污染程度是三级河道二级河道一级河道,无论几级河道市区的水质都劣于郊区和湿地;时间上水质污染程度是枯水期平水期丰水期;另外河道周边人口密度、土地利用类型及其调水对温瑞塘河的水质产生了不同程度的影响.

Spatio-temporal Characteristics and Source Identification of Water Pollutants in Wenruitang River Watershed

Identifying the temp-spatial distribution and sources of water pollutants is of great significance for efficient water quality management pollution control in Wenruitang River watershed, China. A total of twelve water quality parameters, including temperature, pH, dissolved oxygen(DO), total nitrogen(TN), ammonia nitrogen(NH₄⁺-N), electrical conductivity(EC), turbidity(Turb), nitrite-N(NO₂^-), nitrate-N(NO₃^-), phosphate-P(PO₄^3-),total organic carbon(TOC) and silicate(SiO₃^2-), were analyzed from September, 2008 to October, 2009. Geographic information system(GIS) and principal component analysis(PCA) were used to determine the spatial distribution and to apportion the sources of pollutants. The results demonstrated that TN,NH₄⁺-N,PO₄^3- were the main pollutants during flow period, wet period, dry period, respectively, which was mainly caused by urban point sources and agricultural and rural non-point sources. In spatial terms, the order of pollution was tertiary river>secondary river>primary river, while the water quality was worse in city zones than in the suburb and wetland zone regardless of the river classification. In temporal terms, the order of pollution was dry period>wet period>flow period. Population density, land use type and water transfer affected the water quality in Wenruitang River.