摘要
为了探讨巢湖流域地下水硝态氮的空间分布规律,2009年11月至12月在巢湖流域采集了253个地下水样品,分析了其硝态氮含量。结果表明,巢湖流域地下水硝态氮含量平均值为7.13 mg/L,超标率(10mg/L≤NO3--N<20 mg/L)和严重超标率(NO3--N≥20 mg/L)分别为15.81%和7.11%。不同土地类型的地下水硝态氮含量存在一定差异,其中村庄>菜地>果园>旱地>城镇>水稻-油菜(或小麦)轮作田>单季水稻田>养殖场。巢湖流域绿色水稻产区地下水硝态氮含量比非绿色水稻产区低。农田地下水硝态氮含量与化肥氮施用量、人口密度和耕地面积比例呈正相关。农田地下水硝态氮含量具有随地下水位的下降而降低的趋势,但两者之间没有显著相关性。当化肥氮的年施用量超过100 kg/hm2或地下水位低于9 m时,地下水硝态氮含量存在超标的潜在危险。
To investigate the spatial distribution of groundwater nitrate nitrogen（NO-3-N） in the Chao Lake watershed,253 water samples were collected from wells in the watershed from November to December,2009 and their NO-3-N concentrations were analyzed.The results showed that the samples＇ NO-3-N concentrations were averaged 7.13 mg/L,and 15.81% of them exceeded 10 mg/L,the WHO limit for NO-3-N of drinking water,and 7.11% of them exceeded 20 mg/L,the criterion for serious NO-3-N pollution.The NO-3-N concentrations were different in different land types,with the pattern of villagesvegetable fieldsfruit gardensdry landstownsrice-rape（or wheat） fieldssingle-season rice fieldslivestock farms.The NO-3-N concentration of groundwater in Green Rice-Producing Area was lower than that in Non-Green Rice-Producing Area in Chao Lake watershed.The NO-3-N concentration of groundwater in farmlands was positively related to the application rate of nitrogen chemical fertilizer,the population density and the proportion of cultivated area.The NO-3-N concentrations were declined with the lowering of the groundwater table,but there was no significant correlation between them.When the application of chemical fertilizer nitrogen exceeds 100 kg/hm2,or the groundwater table is less than 9 m,the NO-3-N concentration of groundwater has the potential risk of exceeding the WHO limit.
出处
《中国农业科技导报》
CAS
CSCD
2011年第1期68-74,共7页
Journal of Agricultural Science and Technology
基金
“十一五”国家科技支撑计划项目(2007BAD87B01)
国家科技重大专项(2008ZX07425)资助
关键词
巢湖流域
地下水
硝态氮
the Chao Lake watershed
groundwater
nitrate nitrogen
