【作者】 卢丽； 李文莉； 裴建国； 王喆；

【Author】 LU Li;LI Wen-li;PEI Jian-guo;WANG Zhe;Institute of Karst Geology,Chinese Academy of Geological Sciences,Karst Dynamics Laboratory of Ministry of Land and Resources & Guangxi;

【机构】 中国地质科学院岩溶地质研究所,国土资源部/广西壮族自治区岩溶动力学重点实验室；

【摘要】 近些年,随着化肥和农药的广泛使用,地下水中硝酸盐污染日益严峻。本文选择桂林寨底地下河系统为研究区,对研究区进行地下水取样调查以及水化学和氮、氧同位素分析,利用IsoSource软件对其硝酸盐来源进行定量计算,为岩溶区地下水硝酸盐来源定量研究提供了一个新方法。结果表明,寨底地下河硝酸盐主要以NO3–为主,NO3–浓度变化在2.67~17.99 mg/L,平均值为6.3 mg/L,研究区内硝酸盐来源共有三种,分别为化肥、动物粪便与污水和土壤有机氮,其中化肥的变化范围为23%~78%,动物粪便与污水为6%~58%,土壤有机氮为6%~38%。沿地下水流动方向,化肥和动物粪便与污水的比例均发生了明显变化,与离居民区的距离密切相关,距离远时化肥比例较大,动物粪便与污水比例较小,距离近时则相反。更多还原

【Abstract】 In recent years, with the extensive use of chemical fertilizers and pesticides, nitrate contamination in groundwater has become more and more serious with each passing day. Choosing the Zhaidi underground River of Guilin as a study area, the authors analyzed the nitrogen and oxygen isotopes and investigated hydrochemistry for groundwater. This study can provide a new method for quantitative study of groundwater sources of nitrate in the karst area. IsoSource software was used to calculate the sources of nitrate quantitatively. The results show that the nitrate is dominated by NO3 –, the NO3 – concentrations are in the range of 2.67~17.99 mg/L, 6.3 mg/L on average. The sources of nitrate in the study area are animal waste and sewage, fertilizer, and soil organic nitrogen, with fertilizer, animal waste and sewage, and soil organic matter possessing 23%~78%, 6%~58%, and 6%~38% respectively. In the direction of groundwater flow, the proportions of fertilizer and animal waste and sewage vary significantly, closely related to the distance from the residential area. The longer the distance, the larger the proportion of the fertilizer, and the smaller the proportion of the animal waste and sewage.更多还原