土壤学报2011，Vol.48Issue(1)：141-150,10.
密云水库流域地下水硝态氮的分布及其影响因素
NITRATE CONCENTRATION DISTRIBUTION IN GROUNDWATER OF THE MIYUN RESERVOIR WATERSHED
摘要
Abstract
Water samples were collected from 305 wells in the Miyun Reservoir Watershed during the period from November to December, 2008, for analysis of nitrate nitrogen (NO3--N) concentrations. It was found that NO3--N concentrations of the samples averaged 6.81 mg L -1; samples from 13.77％ of the wells exceeded 10 mg L-1 , the WHO limit for NO3- -N in drinking water, and from 2. 3％ of the wells did 20 mg L-1, the criterion for serious NO3--N pollution. Nitrate pollution was the most serious in groundwater under villages and vegetable fields.NO3--N concentrations of the samples from 35 wells in villages and 13 wells in vegetable fields averaged 9.52 mg L-1 and 9.55 mg L-1 , respectively, very close to the WHO limit for drinking water. About 20％ of the wells in village and 15.38％ of the wells in vegetable fields were found to have NO3--N concentrations in groundwaters exceeding 10 mg L-1 , but below 20 mg L-1 and 8.57％ and 7.69％ exceeding 20 mg L-1. Nitrate concentrations in 219 wells on croplands (corn and soybean) were moderate, being 6. 59 mg L-1 on average. About 14.61％ of the wells on cropland were found to have NO3--N concentrations in goundwaters exceeding 10 mg L-1 and 1.37％ exceeding 20 mg L-1 NO3--N concentrations in the 10 wells on woodlands were the lowest with an average being 2.66 mg L -1 and none of them were beyond the WHO limit. Nitrate pollution of groundwater was more severe in the Chaohe River Basin than in the Baihe River Basin. Average NO3--N concentration in the groundwater from farmlands in the Chaohe River Basin reached 8.42 mg L-1, higher than that (5.03 mg L-1 ) in the Baihe River Basin.NO3- -N concentrations in 21.77％ of the 124 wells on farmlands in the Chaohe River Basin exceeded 10 mg L-1 while only 6.56％ of the 122 wells in Baihe River Basin did, and 3.23％ of the 124 wells on farmlands in the Chaohe River Basin exceeded 20 mg L-1 while none in the Baihe River Basin did. NO3--N concentration of groundwater in farmlands alongside the rivers increased from upstream to downstream, and It lowers in the corn fields near the rivers, and is negatively related with groundwater table and positively with application rate of chemical fertilizer nitrogen. When the groundwater table gets less than 7 m or the application rate of chemical fertilizer nitrogen in the current year exceeds 200 kg hm -2, a potential risk exists of NO3- -N concentration exceeding the WHO limit in the groundwater.关键词
硝态氮/地下水/密云水库流域Key words
Nitrate/ Groundwater/ Miyun Reservoir Watershed分类
资源环境引用本文复制引用
王庆锁,孙东宝,郝卫平,顾颖,李玉中,梅旭荣,张燕卿..密云水库流域地下水硝态氮的分布及其影响因素[J].土壤学报,2011,48(1):141-150,10.基金项目
国家科技支撑计划项目"沿湖地区农业面源污染阻控关键技术研究"(课题编号:2007BAD87B01)、北京市科技计划项目(编号:D0705045040391)和国家科技重大专项"华北村镇地下饮用水安全保障技术研究与示范"(课题编号:2008ZX07425)共同资助 （课题编号:2007BAD87B01）
