摘要
为了揭示滇池NO3-的污染来源和污染途径,本次研究在滇池流域不同地区收集了14个地下水和35个河水样品,进行了水化学及氮同位素分析。结果显示,滇池流域河水NO3-浓度在0.01~45.92mg/L之间,地下水NO3-浓度在0.05~99.52mg/L之间。NO3-浓度较高的区域,集中在流域城镇居民区(41.41±39.32mg/L)和昆明市主城区(19.91±15.02mg/L)。林地泉水、盘龙江上游以及流域东、南部河水NO3-浓度较低,污染较轻。δ15 N-NO3-值显示,流域居民区地下水(+9.9‰^+27.8‰)与主城区河水(+3.2‰^+32.1‰)中NO3-的主要来源是生活污水,流域东、南面河水(+4.4‰^+7.2‰)NO3-污染源以化肥为主。林地泉水与盘龙江上游河水δ15 N-NO3-值均小于+10‰,大气沉降是人为N的主要来源。耕地地下水δ15 N-NO3-值变化范围较宽(+5.5‰^+23.7‰),NO3-浓度高(45.77±40.91mg/L),受农业生产的影响强烈,人畜粪便、化肥肥料、大气沉降都是氮的输入源。
To assess nitrate pollution and identify its potential sources, groundwater and river water were sampled in the Dianchi Lake Basin, China. Water chemistry and nitrogen isotopes were determined for the samples. The results showed the concentra- tions of NO3- in the groundwater and river water range from 0.05 to 99.52 mg/L and from 0.01 to 45.92 mg/L, respectively. The high NO3- concentrations often occur in the residential area （41.41±39.32 mg/L, n=8） and Kunming City （19.91± 15.02 mg/L,n=24）, and the low NO3- concentrations appear in the spring water in woodland spring and in the upstream water of the Panlongjiang River, as well as in the streams in the southern and eastern areas of the watershed. The nitrogen isotop- ic compositions showed that NO3- in the groundwater in residential areas （＋ 9.9‰--＋27.8‰） and in the river water in Kun- ming City （＋3.2‰--＋32.1‰） originates mainly from domestic sewage. NO3- pollution in the river water in the southern and eastern parts of the drainage basin is derived from chemical fertilizers. The low δ15 N-NO3- values （＋ 10‰） occurring in the woodland spring and upstream water of the Panlongjiang River indicated that atmospheric deposit is the main source of anthro- pogenic N. With a large range of δ15 N-NO3- values （＋ 5.5‰ ＋23.7‰） and higher concentrations of nitrate （45.77±40.91 mg/L）, nitrate in groundwater in the cultivated land is mainly derived from human and animal wastes, chemical fertilizers and atmospheric deposits.
出处
《地球与环境》
CAS
CSCD
北大核心
2014年第5期589-596,共8页
Earth and Environment
基金
国家重大科学研究计划(2013CB956700)
关键词
滇池流域
硝态氮
水化学
氮同位素
Dianchi Lake Basin； nitrates hydrochemistry； nitrogen isotope
