As nitrate pollution in groundwater has become increasingly serious in recent years, nitrogen isotope was adopted in this paper to define its sources in a typical agricultural area of Dong5e hydrogeological unit. The ...As nitrate pollution in groundwater has become increasingly serious in recent years, nitrogen isotope was adopted in this paper to define its sources in a typical agricultural area of Dong5e hydrogeological unit. The results show that: Higher content of NO3^- detected in shallow groundwater is 27.77 mg/L on average and δ^15N content ranges from 7.8‰ to 12 ‰, indicating that shallow groundwater is mainly contaminated by sewage or feces. In contrast, less NO3^- in deep groundwater (karst water) has an average value of 12.81 mg/L and δ^15N content is between 7.2‰ and 14.3‰, which is closely related to human disturbance as mentioned above. In addition, considering relatively low groundwater quality at some monitoring sites, reasonable fertilization is a better choice in the study area to reduce nitrate source in groundwater.展开更多
基金supported by the Shandong Provincial Natural Science Foundation, China (No. ZR2017QD017)Special Support for Post-doc Creative Funding in Shandong Province (No. 201502020)
文摘As nitrate pollution in groundwater has become increasingly serious in recent years, nitrogen isotope was adopted in this paper to define its sources in a typical agricultural area of Dong5e hydrogeological unit. The results show that: Higher content of NO3^- detected in shallow groundwater is 27.77 mg/L on average and δ^15N content ranges from 7.8‰ to 12 ‰, indicating that shallow groundwater is mainly contaminated by sewage or feces. In contrast, less NO3^- in deep groundwater (karst water) has an average value of 12.81 mg/L and δ^15N content is between 7.2‰ and 14.3‰, which is closely related to human disturbance as mentioned above. In addition, considering relatively low groundwater quality at some monitoring sites, reasonable fertilization is a better choice in the study area to reduce nitrate source in groundwater.
