绵阳市农业面源污染特征与区域差异分析

Analysis of Agricultural Non-point Source Pollution and Regional Difference in Mianyang City

对2003-2011年绵阳市农业面源污染情况及2011年其下辖9个地区的污染差异情况进行分析,为合理制定农业面源污染防控措施提供科学依据。结果表明,2003-2011年绵阳市农药、农膜、农作物秸秆污染总体上呈逐渐加重趋势,农村生活垃圾污染总体上呈减缓趋势;营养污染物(CODCr、TN、TP)主要来源于畜禽养殖业、化肥和农村生活,畜禽养殖业和化肥营养污染物污染总体上呈增加趋势,而农村生活营养污染物污染总体上呈减缓趋势,但营养污染物污染总体上呈增加趋势。2011年,涪城区的农药、农膜、农作物秸秆、农村生活垃圾污染总体最严重,其次是三台县和江油市;三台县营养污染物等标污染负荷最高,涪城区和盐亭县营养污染物耕地负荷较高。耕地负荷系数表明,CODCr、TN、TP污染在各地区之间差异明显,其对江油市、涪城区、盐亭县的环境构成严重威胁,对平武县环境不构成威胁;对所有污染物耕地负荷进行聚类分析表明,江油市、游仙区、涪城区、三台县、盐亭县为重度污染区,北川县、安县、梓潼县为中度污染区,平武县为轻度污染区。

Agricultural non-point source pollution situation in Mianyang city during 2003-2011 and the difference of agricultural non-point source pollution among nine regions under Mianyang city’s respective jurisdiction in 2001 were analyzed,which could provide scientific basis for putting forward appropriate measures to control agricultural non-point source pollution.The results indicated that the pollutions of pesticides,agricultural film and crop straw increased,and rural domestic garbage pollution reduced during 2003-2011.The nutrient pollutants（CODCr,TN and TP）came from livestock and poultry,fertilizer and rural domestic waste,and showed an rising trend in general,nutrient pollutants from livestock and poultry and fertilizer increased,but the nutrient pollutants from rural domestic wast reduced.In 2011,the pollution of pesticide, agricultural film,crop straw and rural domestic waste was the most serious in Fucheng district, followed by Santai county and Jiangyou city;the total equivalent pollution load of nutrient pollutants was the highest in Santai county,and land loads of nutrient pollutants in Fucheng district and Yanting county were higher than the other regions.Land loads coefficient indicated that pollution of CODCr ,TN and TP presented obvious regional differences,and posed a serious threat to environment of Jiangyou city,Fucheng district and Yanting county and little threat to environment of Pingwu county.The cluster analysis of all pollutants indicated that Jiangyou city, Youxian district,Fucheng district,Santai county and Yanting county were heavy pollution area,nbsp;middle pollution area included Beichuan county,Anxian county and Zitong county,Pingwu county was slight pollution area.