基于模型模拟法的地下水氨氮-硝氮防污性能评价——以北京市昌平区为例  

Groundwater Vulnerability to Ammonia and Nitrate Based on Modeling Simulation Method: A Case Study in Changping District of Beijing

作　　者：贾永锋[1,2] 郭华明[1,2] 魏亮[1] 

机构地区：[1]中国地质大学生物地质和环境地质国家重点实验室,北京100083 [2]中国地质大学(北京)水资源与环境学院,北京100083

出　　处：《现代地质》2015年第2期316-323,共8页Geoscience

基　　金：国家重点基础研究发展计划("973"计划)项目(2010CB428804);北京市科技计划项目(D07050601510000);中国地质调查局项目(1212010813104)

摘　　要：地下水防污性能评价是开展地下水保护工作的前提,可以为城镇的规划建设提供参考,具有很强的现实意义。常用的DRASTIC地下水防污性能评价模型简单,易于操作,但该模型是针对所有污染物总体考量,没有考虑到特定污染物在包气带中发生的各种生化作用,只是人为的依据经验值进行评分赋值,具有一定的缺陷性。因此,本次研究针对两种特定污染物氨氮、硝氮,定量了其在包气带中的吸附和生物转化作用,以模型模拟法的LPI模型对北京市昌平区地下水的防污性能进行了评价。评价结果表明,昌平区地下水对于氨氮、硝氮的防污性能具有很好的分带性。从山前到平原,地下水的防污性能逐渐增强。地下水对于氨氮的防污性能好于硝氮。此外,地下水大量开采导致的地下水位下降,也增强了地下水的防污性能。由于地下水的持续开采,2009年地下水对于氨氮、硝氮的防污性能普遍好于2005年。Assessment of groundwater vulnerability is a prerequisite to protect groundwater resources. It can provide a reference to city planning and construction and has a strong practical significance. The DRASTIC, which is a commonly used for groundwater vulnerability assessment model, had an extensive application in vari- ous countries since it is simple and easy to operate. However, the model just gives an overall consideration of general pollutants, and does not take into account biochemical processes of specific pollutants occurring in the vadose zone. It gets the score based on expert experience, which has a certain shortage. The LPI assessment model, which includes adsorption and biodegradation processes of ammonia and nitrate in the vadose zone, is selected to assess groundwater vulnerability to ammonia and nitrate in Changping area of Beijing. Results show that groundwater vulnerability to ammonia and nitrate has a good distribution trend in this area. From the alluvi- al fans to the flat plain than nitrate. Besides, , groundwater vulnerability enhan the decrease in groundwater table ces gradually. The vulnerability to ammonia is greater caused by exploitation lowers groundwater vulnerabili-ty. The groundwater vulnerability in 2005 is lower compared with 2009 due to the consistent groundwater exploi- tation. The assessment result is well consistent with groundwater quality data, indicating that the LPI model can be used for groundwater vulnerability assessment.

关 键 词：地下水防污性能 氨氮 硝氮 昌平 北京 

分 类 号：P641[天文地球—地质矿产勘探]