基于清单分析的江苏省农业面源污染时空特征及源解析

Temporal and spatial characteristics and source apportionment of agricultural non-point source pollution in Jiangsu Province based on inventory analysis

通过清单分析方法,估算了江苏省总体的及其13个城市的农田化肥、畜禽养殖、水产养殖、农田固体废弃物以及农村生活等5类主要农业面源污染来源化学需氧量(COD)、总氮(TN)和总磷(TP)的排放总量、排放浓度及其贡献率,从时间和空间的角度分析了江苏省在1990～2009年间农业面源污染变化程度及各市分布差异。结果表明,江苏省农业面源污染COD、TN和TP的排放总量从1990年的64.20、54.29和4.78万t增加到2009年的96.88、72.87和8.33万t,排放浓度从1990年的20.978、17.740和1.560 mg·L-1增加到31.654、23.810和2.721mg·L-1。2009年江苏省13个城市的农业面源污染差异较大,COD、TN、TP的排放总量分别在2.459～17.263、1.619～14.403、0.177～1.757万t,排放浓度分别在11.261～105.597、6.135～90.005、0.813～9.239 mg·L-1。农业面源污染COD和TP的主要来源是畜禽养殖,而TN的主要来源是农田化肥。

The inventory analysis method was used to determine the discharge amount, density, and contribution of chemical oxygen demand （COD）, total nitrogen （TN）, and total phosphorus （TP） from different types of agricultural non-point sources, including chemical fertilizer application, livestock farming, aquaculture, farmland solid waste, and rural life in Jiangsu province and other 13 cities in Jiangsu. The results indicated that the discharge amount of COD, TN, and TP were increased from 64.20, 54.29, and 4.78 to 96.88, 72.87, and 8.33 ten thousand tons, respectively. The densities of COD, TN, and TP were increased from 20.978, 17.74 and 1.560 mg·L-1 to 31.654, 23.810 and 2.721 mg·L-1 in Jiangsu province from year 1990 to 2009. There were significant differences in the 13 cities in Jiangsu. For example, the discharge amount of COD, TN, and TP were in the range of 24.59-172.63, 16.19-144.03 and 1.77-17.57 ten thousand tons, and the densities of COD, TN, and TP were 11.261-105.597, 6.135-90.005 and 0.813-9.239 mg·L-1, separately. Livestock farming was the most important source of COD and TP, while chemical fertilizer application was the most important source of TN.