川中丘陵区小流域非点源氮污染特征——以中国科学院盐亭紫色土农业生态试验站小流域为例

Non-point source pollution of nitrogen in a small watershed in hilly area of the central Sichuan Basin ——a case study in the watershed of Yanting agro-ecological experimental,CAS

通过2002年5月至2002年12月对川中丘陵区小流域地表水—地下水中氮素各种形态的监测分析。结果表明,集水区、农田径流水无机氮的平均浓度分别达1 06mg/L和1 11mg/L,超过水体富营养化的浓度下限;井水中NO-3-N浓度最高达14 23mg/L,超过WHO所规定的生活饮用水NO-3-N浓度上限的42 3%;平均浓度为7 03mg/L。井水中氮素存在形态以NO-3-N为主,平均占97 6%,最高达99 4%。集水区、农田径流水、井水中NO-4-N浓度随时间变化差异显著。3-N和NH+各水体NO-2-N含量很低,低于0 1mg/L。

Eutrophication and nitrate contamination of the surface-ground water aroused nationwide concern recently.NO^-_3-N?NH^+_4-N and NO^-_2-N concentrations were monitored twice a month in a small watershed in hilly area of the central Sichuan Basin from May 26,2002 to December 26,2002.Results showed that inorganic N (sum of NO^-_3-N?NH^+_4-N and NO^-_2-N) amounted to 1.06mg/L and 1.11mg/L in surface water of this watershed and runoff in slope cropland,respectively,which exceeded eutrophication limit.The maximum ...