浅层岩溶地下水滞留时间对硝酸盐氮迁移转化的影响研究

Residence time of shallow groundwater is important in assessment of groundwater renewability, understanding of groundwater flow system and migration of contaminants in groundwater. In this study, the Houzhai river basin located in Puding County, Guizhou Province, China has been selected as the major study area. Based on the hydrological observations, environmental isotopes, groundwater dating and hydrochemical analysis, three major problems will be settled in this study: the estimation of CFCs and SF6 apparent age and the effect of recharge and redox conditions, the mechanism of groundwater mixing and flow pathways of groundwaters with different residence time, the effect of residence time and mixing of groundwaters with different residence time on migration and fate of nitrate-nitrogen. Thus, the theoretical advancements and empirical evidence for study of karstic groundwater cycle and management of groundwater resource will be provided.

浅层地下水的滞留时间对评价地下水更新能力、正确认识地下水流动系统和地下水污染物迁移规律具有重要作用。本项目拟以贵州省普定县典型喀斯特小流域后寨河流域为研究区，利用水文观测、水文地球化学、年龄示踪及环境同位素等解析手段，评价补给条件和氧化还原条件对岩溶地下水的CFCs和SF6表观年龄的影响，揭示不同滞留时间地下水的混合过程及流动路径；进而探讨地下水滞留时间及不同滞留时间地下水的混合过程对硝酸盐氮迁移转化机理的影响，为喀斯特地下水循环研究及地下水资源管理提供科学依据。