Work

Multi-Isotope-Based Tracing of Drainage Nitrogen Behavior and Surface and Groundwater Pathways in High-Nitrogen Rare Earth Mines

Year: 2024

Type: article

Abstract: High-nitrogen mining drainage (HNMD) is a significant source of watershed nitrogen pollution, influencing the nitrogen distribution in streams through various pathways, including surface runoff (HNMDs) and subsurface runoff (HNMDg). In this study, the nitrogen contributions of HNMDs and HNMDg were characterized by using water chemistry analysis, isotope analysis, and a Bayesian stable isotope mixing model. The combined effects of HNMDs, HNMDg, and domestic sewage (DS) were found to substantially impact nitrogen dynamics in the study area. On average, HNMDs and HNMDg contributed 60.5 ± 8.8% and 19.8 ± 12.5%, respectively, to riverine nitrogen. After accounting for the exclusion of DS, the dominance of HNMDs became more pronounced, contributing 67.0 ± 4.1% and 81.9 ± 0.1% of the HNMD nitrogen in the Chakeng and Caiyang Rivers, respectively. HNMDs and HNMDg displayed distinct nitrogen discharge behaviors within the watershed, which influenced the observed variations in nitrogen fluxes. Precipitation had a stronger influence on nitrogen discharge from HNMDs compared to HNMDg. Furthermore, NH4+-N from HNMD was more likely to enter streams via surface runoff, while HNMDg served as a critical and relatively stable source of nitrogen discharge.

Source: Water

DOI: 10.3390/w16233366

Authors: Yu Zhang, Rui Wang, Changyuan Tang, Quanzhou Gao, Jianhong Zhong, Yingjie Cao

Institutions: Sun Yat-sen University, Powerchina Huadong Engineering Corporation (China), Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Ministry of Ecology and Environment

Language: English

Topic: Groundwater and Isotope Geochemistry

Subfield: Geochemistry and Petrology

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDG: Clean water and sanitation

Open Access status: gold

Estimated APC paid: $2,955