江西省农业面源污染时空特征及污染风险分析

为了确定江西省农村饮用水源地重点控制区域,本文通过估算11个地市农业面源污染负荷进行污染风险分析。采用排污系数法及统计年鉴估算2011—2015年农业面源污染的化学需氧量(COD)、总氮(TN)、总磷(TP)污染负荷,并结合ArcGIS表征COD、TN、TP污染负荷及污染强度的空间分布情况,采用离差标准化法分析COD、TN、TP污染强度。结果表明,2015年江西省农村地区COD、TN及TP污染负荷分别为455.3、168.7 kt·a-1及58.8 kt·a-1;2011—2015年COD、TN及TP污染负荷整体呈现逐年下降的趋势;江西省农业面源污染主要贡献顺序为:农村生活畜禽养殖种植业水产养殖;不同污染物的污染负荷、污染强度与污染风险空间分布特征一致,其中污染负荷呈西高东低的特点,污染强度呈中部高、四周低的特点,污染风险与污染强度空间分布特征较为一致;11个地市农村面源污染风险顺序为:南昌萍乡鹰潭宜春新余抚州上饶赣州九江景德镇吉安。

Analysis on spatio-temporal characteristics of agricultural non-point sources pollution and pollution risk in Jiangxi Province, China

To determine the key control areas of rural drinking water sources in Jiangxi Province, the agricultural non-point sources pollution (ANPSP) risk, which based on the distribution of pollution load and intensity of chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) in 11 cities, was analyzed by the emission coefficient method and Statistical Yearbook of Jiangxi Province during 2011 to 2015. Combined with ArcGIS to characterize the spatial distribution of COD, TN, TP pollution load and pollution intensity, the method of dispersion standardization was used to analyze the sequence of the pollution risk. The results showed that the total load of COD, TN and TP in ANPSP of Jiangxi Province in 2015 were 455.3, 168.7 and 58.8 kt·a^-1 respectively. The total load of COD, TN and TP in 2011-2015 showed a slight decreasing trend year by year. The main contribution sequence of rural non-point source pollution in Jiangxi Province was:rural life > livestock and poultry breeding > crop farming > aquaculture. The spatial analysis showed the similar distribution characteristics of pollution load and pollution intensity in different pollutants, and showed different distribution characteristics of pollution load and pollution intensity in single pollutant. The pollution load of single pollutant was higher in the west and lower in the east of Jiangxi Province, and the pollution intensity of single pollutant was higher in the middle and lower around. The pollution risk sequence of ANPSP in the 11 cities was Nanchang > Pingxiang > Yingtan > Yichun > Xinyu > Fuzhou > Shangrao > Ganzhou > Jiujiang > Jingdezhen > Ji''an.