Using δ15N- and δ18O-Values To Identify Nitrate Sources in Karst Ground Water, Guiyang, Southwest China

Citations Over TimeTop 10% of 2006 papers

Abstract

Nitrate pollution of the karstic groundwater is an increasingly serious problem with the development of Guiyang, the capital city of Guizhou Province, southwest China. The higher content of NO3- in groundwater compared to surface water during both summer and winter seasons indicates that the karstic groundwater system cannot easily recover once contaminated with nitrate. In order to assess the sources and conversion of nitrate in the groundwater of Guiyang, we analyzed the major ions, delta(15)N-NH4+, delta(15)N-NO3-, and delta(18)O-NO3- in surface and groundwater samples collected during both summer and winter seasons. The results show that nitrate is the major dominant species of nitrogen in most water samples and there is a big variation of nitrate sources in groundwater between winter and summer season, due to fast response of groundwater to rain or surface water in the karst area. Combined with information on NO3- /Cl-, the variations of the isotope values of nitrate in the groundwater show a mixing process of multiple sources of nitrate, especially in the summer season. Chemical fertilizer and nitrification of nitrogen-containing organic materials contribute nitrate to suburban groundwater, while the sewage effluents and denitrification mainly control the nitrate distribution in urban groundwater.

Related Papers

• → High biodiversity and distinct assembly patterns of microbial communities in groundwater compared with surface water(2022)39 cited
• → Evaluation of Temporal Contribution of Groundwater to a Small Lake through Analyses of Water Quantity and Quality(2020)20 cited
• → An investigation of nitrate and iron concentrations and their relationship in shallow groundwater systems of Kathmandu(2010)15 cited
• → Unexpected nationwide nitrate declines in groundwater of Korea(2017)8 cited
• Relationship between surface water and groundwater in the second Songhua River basin(2014)