秦淮河典型河段总氮总磷时空变异特征

2010年6月～2011年5月,对秦淮河典型河段水体总氮(TN)、总磷(TP)的污染状况进行了周年定点观测,采用传统统计学方法初步探讨了秦淮河水体TN、TP污染状况及时空间变化特征.结果表明,秦淮河TN、TP污染严重,且具有很强的时空变异性.秦淮河传统农业区、集约农业区和城市区TN平均浓度分别为1.80、3.97、9.25 mg·L-1,TP平均浓度分别为0.03、0.11、0.50 mg·L-1,表明秦淮河TN、TP主要来源于城市区和集约农业区,而传统农业区对水体TN、TP贡献较小.秦淮河丰水期和枯水期TN平均浓度分别为1.89、4.58 mg·L-1,TP平均浓度分别为0.11、0.14 mg·L-1,表明秦淮河枯水期较丰水期污染严重.富营养化评价结果显示,秦淮河河段大都处于富营养化状态,应及时采取治理措施.

Temporal and Spatial Variations of Total Nitrogen and Total Phosphorus in the Typical Reaches of Qinhuai River

The year-round concentrations of total nitrogen (TN) and total phosphorus(TP) were monitored from June 2010 to May 2011 in the typical reaches of the Qinhuai River. The spatial and temporal variations in TN and TP concentrations and the pollution status of the river water were investigated using typical statistics analysis. Results showed that the river water was seriously polluted in terms of TN and TP, and that the concentrations of both TN and TP showed high spatial and temporal variations. The average TN concentrations of the river water in the traditionally managed agricultural area, intensively managed agricultural area, and urban area were 1.80, 3.97 and 9.25 mg·L^-1, respectively; The corresponding average TP concentrations were 0.03, 0.11 and 0.50 mg·L^-1, respectively, showing similar spatial patterns with those of TN. The spatial variations in TN and TP concentrations in river water indicated that the urban area and intensively managed agricultural area,rather than the traditionally managed agricultural area,were the major sources for TN and TP in the river water. The average TN concentrations of river water during the wet season and dry season were 1.89 and 4.58 mg·L^-1, respectively; and the corresponding average TP concentrations were 0.11 and 0.14 mg·L^-1,respectively. The temporal variations indicated that the pollution status of the river water was more serious during the dry season than that during the wet season. Assessment results of eutrophication indicated that the majority of Qinhuai River reaches were in the stage of eutrophication, thus deserving immediate controlling measures.