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Ding H, Gao H, Zhu M, Yu M, Sun Y, Zheng M, Su J, Xi B. Spectral and molecular insights into the characteristics of dissolved organic matter in nitrate-contaminated groundwater. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 355:124202. [PMID: 38788994 DOI: 10.1016/j.envpol.2024.124202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 04/11/2024] [Accepted: 05/17/2024] [Indexed: 05/26/2024]
Abstract
The characteristics of dissolved organic matter (DOM) serve as indicators of nitrate pollution in groundwater. However, the specific DOM components associated with nitrate in groundwater systems remain unclear. In this study, dual isotopes of nitrate, three-dimensional Excitation emission matrices (EEMs) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) were utilized to uncover the sources of nitrate and their associations with DOM characteristics. The predominant nitrate in the targeted aquifer was derived from soil organic nitrogen (mean 46.0%) and manure &sewage (mean 34.3%). The DOM in nitrate-contaminated groundwater (nitrate-nitrogen >20 mg/L) exhibited evident exogenous characteristics, with a bioavailable content 2.58 times greater than that of uncontaminated groundwater. Regarding the molecular characteristics, DOM molecules characterized by CHO + 3N, featuring lower molecular weights and H/C ratios, indicated potential for mineralization, while CHONS formulas indicated the exogenous features, providing the potential for accurate traceability. These findings provided insights at the molecular level into the characterization of DOM in nitrate-contaminated groundwater and offer scientific guidance for decision-making regarding the remediation of groundwater nitrate pollution.
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Affiliation(s)
- Hongyu Ding
- College of Water Science, Beijing Normal University, Beijing, 100875, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Huan Gao
- CCCC Water Transportation Consultants Co., Ltd, Beijing, 100010, China
| | - Mingtan Zhu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Minda Yu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; School of Environment and Civil Engineering, Jiangnan University, Wuxi, 214122, China
| | - Yuanyuan Sun
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Mingxia Zheng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
| | - Jing Su
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Beidou Xi
- College of Water Science, Beijing Normal University, Beijing, 100875, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
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Shan Q, Tian X, Xie H, Gong Z, Lin Y, Dang Z, Li J, Zou S, Zhu T. Hydrogeochemical characteristics, driving factors, and health risk assessment of karst groundwater in Southwest Hubei Province, China. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2024; 96:e11069. [PMID: 39024497 DOI: 10.1002/wer.11069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 06/02/2024] [Accepted: 06/07/2024] [Indexed: 07/20/2024]
Abstract
In South China, karst groundwater is an important water resource for industrial, agricultural, and drinking purposes. However, karst aquifers are highly vulnerable to pollution, leading to deteriorating karst groundwater quality and posing potential health risks to local residents. In this study, 22 groundwater samples were collected from a karst aquifer in the southwestern part of Hubei Province. The hydrogeochemical characteristics and their controlling factors were examined, and the potential health risks associated with groundwater pollutant concentrations in karst groundwater were assessed. The results showed that the groundwater is slightly alkaline with low chemical oxygen demand values, indicating good water quality. The groundwater facies type was identified as HCO3-Ca at most sample spots, showing low total dissolved solids concentrations. Substantial spatial variations in Na+, CO3 2-, and NO2 - concentrations were found, whereas spatial variations in the K+, Ca2+, Cl-, HCO3 -, and F- concentrations were small. In addition, the dissolution of gypsum deposits and magnesium carbonate sedimentary rocks at sampling sites resulted in groundwater facies types of HCO3•SO4-Ca and HCO3-Ca•Mg, with low total dissolved solids concentrations. The karst groundwater chemistry in the study area was mainly controlled by water-rock interactions, as well as by the dissolution of gypsum deposits and magnesium carbonate sedimentary rocks at specific groundwater sampling sites. The groundwater Cl- concentrations were mainly affected by atmospheric precipitation. NO3 - was mainly derived from atmospheric precipitation, domestic sewage, septic tanks, and industrial activities, whereas SO4 2- was derived from atmospheric precipitation, sulfate rock dissolution, and sulfide mineral oxidation. These results highlight the absence of potential human health risks of NO3 - and F- to infants, children, and adults, as their concentrations are below the corresponding regional background values. In contrast, the potential health risks of Cl- cannot be ignored, particularly for infants. This study offers scientific guidelines for protecting and allocating local groundwater resources.
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Affiliation(s)
- Qiang Shan
- Hebei Key Laboratory of Geological Resources and Environment Monitoring and Protection, Hebei Geological Environment Monitoring Institute, Shijiazhuang, China
| | - Xizhao Tian
- Hebei Key Laboratory of Geological Resources and Environment Monitoring and Protection, Hebei Geological Environment Monitoring Institute, Shijiazhuang, China
| | - Hao Xie
- Key Laboratory of Karst Dynamics, MNR&GZAR, Institute of Karst Geology, CAGS, Guilin, China
- Guangxi Karst Resources and Environment Research Center of Engineering Technology, Guilin, China
| | - Zhiqiang Gong
- Hebei Key Laboratory of Geological Resources and Environment Monitoring and Protection, Hebei Geological Environment Monitoring Institute, Shijiazhuang, China
| | - Yongsheng Lin
- Key Laboratory of Karst Dynamics, MNR&GZAR, Institute of Karst Geology, CAGS, Guilin, China
- Guangxi Karst Resources and Environment Research Center of Engineering Technology, Guilin, China
| | - Zhiwen Dang
- Hebei University of Architecture, Zhangjiakou, China
| | - Jun Li
- Hebei University of Architecture, Zhangjiakou, China
| | - Shengzhang Zou
- Key Laboratory of Karst Dynamics, MNR&GZAR, Institute of Karst Geology, CAGS, Guilin, China
| | - Tianlong Zhu
- Hebei University of Architecture, Zhangjiakou, China
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Xue S, Wang Y, Jiang J, Tang L, Xie Y, Gao W, Tan X, Zeng J. Groundwater heavy metal(loid)s risk prediction based on topsoil contamination and aquifer vulnerability at a zinc smelting site. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 341:122939. [PMID: 37981182 DOI: 10.1016/j.envpol.2023.122939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 11/07/2023] [Accepted: 11/12/2023] [Indexed: 11/21/2023]
Abstract
Groundwater pollution is a recurrent problem in abandoned non-ferrous metal smelting sites, and its severity is influenced by topsoil contamination, hydrogeological characteristics, and hydrogeochemical conditions. In such unique areas, traditional methods for evaluating groundwater pollution risk are biased, as the long production history of these sites have led to highly polluted and heterogeneous soil and groundwater. Herein, based on a typical lead-zinc smelting site, As, Pb, Zn, Cd, Mn, and Ni were found to be the predominant heavy metal (loid)s in groundwater, with respective exceedance rates of 44.4%, 50.0%, 72.2%, 88.9%, 88.9%, and 61.1%. Combined with the groundwater pollution characteristics, the representative hydrogeochemical factors were screened out to optimize the following aquifer vulnerability evaluation using the AHP-DRASTICH method. A comprehensive evaluation model (DI-NCPI) for groundwater pollution risk was established by combining the DRASTICH index (DI) obtained after optimization and the Nemerow comprehensive contamination index (NCPI) of topsoil. The fit between DI-NCPI and groundwater heavy metal (loid) pollution index reached 0.956, which laterally confirms that the model has some reference value. In terms of distribution, the high-risk and very high-risk zones were mainly concentrated in the zinc smelting system, located in the southeastern and central-western parts of the site. These areas have relatively high levels of topsoil contamination and aquifer vulnerability and require focused attention in site remediation. This research highlights the importance of combining topsoil contamination and aquifer vulnerability to evaluate groundwater pollution risk in smelting areas. It provides a more targeted reference for groundwater remediation strategies in abandoned smelting sites, as well as severely polluted industrial areas.
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Affiliation(s)
- Shengguo Xue
- School of Metallurgy and Environment, Central South University, Changsha 410083, PR China; Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Central South University, Changsha 410083, PR China.
| | - Yuanyuan Wang
- School of Metallurgy and Environment, Central South University, Changsha 410083, PR China
| | - Jun Jiang
- School of Metallurgy and Environment, Central South University, Changsha 410083, PR China; Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Central South University, Changsha 410083, PR China
| | - Lu Tang
- School of Metallurgy and Environment, Central South University, Changsha 410083, PR China
| | - Yi Xie
- New World Environment Protection Group of Hunan, Changsha 410083, PR China
| | - Wenyan Gao
- School of Metallurgy and Environment, Central South University, Changsha 410083, PR China
| | - Xingyao Tan
- School of Metallurgy and Environment, Central South University, Changsha 410083, PR China
| | - Jiaqing Zeng
- School of Metallurgy and Environment, Central South University, Changsha 410083, PR China
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Qiao Z, Sheng Y, Wang G, Chen X, Liao F, Mao H, Zhang H, He J, Liu Y, Lin Y, Yang Y. Deterministic factors modulating assembly of groundwater microbial community in a nitrogen-contaminated and hydraulically-connected river-lake-floodplain ecosystem. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 347:119210. [PMID: 37801950 DOI: 10.1016/j.jenvman.2023.119210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/25/2023] [Accepted: 09/30/2023] [Indexed: 10/08/2023]
Abstract
The river-lake-floodplain system (RLFS) undergoes intensive surface-groundwater mass and energy exchanges. Some freshwater lakes are groundwater flow-through systems, serving as sinks for nitrogen (N) entering the lake. Despite the threat of cross-nitrogen contamination, the assembly of the microbial communities in the RLFS was poorly understood. Herein, the distribution, co-occurrence, and assembly pattern of microbial community were investigated in a nitrogen-contaminated and hydraulically-connected RLFS. The results showed that nitrate was widely distributed with greater accumulation on the south than on the north side, and ammonia was accumulated in the groundwater discharge area (estuary and lakeshore). The heterotrophic nitrifying bacteria and aerobic denitrifying bacteria were distributed across the entire area. In estuary and lakeshore with low levels of oxidation-reduction potential (ORP) and high levels of total organic carbon (TOC) and ammonia, dissimilatory nitrate reduction to ammonium (DNRA) bacteria were enriched. The bacterial community had close cooperative relationships, and keystone taxa harbored nitrate reduction potentials. Combined with multivariable statistics and self-organizing map (SOM) results, ammonia, TOC, and ORP acted as drivers in the spatial evolution of the bacterial community, coincidence with the predominant deterministic processes and unique niche breadth for microbial assembly. This study provides novel insight into the traits and assembly of bacterial communities and potential nitrogen cycling capacities in RLFS groundwater.
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Affiliation(s)
- Zhiyuan Qiao
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Yizhi Sheng
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China.
| | - Guangcai Wang
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China.
| | - Xianglong Chen
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Fu Liao
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Hairu Mao
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Hongyu Zhang
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Jiahui He
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Yingxue Liu
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Yilun Lin
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Ying Yang
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
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5
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Jiang W, Meng L, Liu F, Sheng Y, Chen S, Yang J, Mao H, Zhang J, Zhang Z, Ning H. Distribution, source investigation, and risk assessment of topsoil heavy metals in areas with intensive anthropogenic activities using the positive matrix factorization (PMF) model coupled with self-organizing map (SOM). ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:6353-6370. [PMID: 37310651 DOI: 10.1007/s10653-023-01587-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 04/21/2023] [Indexed: 06/14/2023]
Abstract
Over the past decade, heavy metal (HMs) contamination in soil environments has become severe worldwide. However, their resulting ecological and health risks remained elusive across a variety of soil ecosystems due to the complicated distributions and sources. This study investigated the HMs (Cr, As, Cu, Pb, Zn, Ni, Cd, and Hg) in areas with multi-mineral resources and intensive agricultural activities to study their distribution and source apportionment using a positive matrix factorization (PMF) model coupled with self-organizing map (SOM). The potential ecological and health risks were assessed in terms of distinct sources of HMs. The results disclosed that the spatial distribution of HM contaminations in the topsoil was region-dependent, primarily located in areas with high population intensity. The geo‑accumulation index (Igeo) and enrichment factor (EF) values collectively displayed that the topsoils were severely contaminated by Hg, Cu, and Pb, particularly in residential farmland areas. The comprehensive analysis combined with PMF and SOM identified both geogenic and anthropogenic sources of HMs including natural, agricultural, mining, and mixed sources (caused by multi-anthropogenic factors), accounting for 24.9%, 22.6%, 45.9%, and 6.6% contribution rates, respectively. The potential ecological risk was predominantly due to the enrichment of Hg, followed by Cd. The non-carcinogenic risks were mostly below the acceptable risk level, while the potential carcinogenic health risks caused by As and Cr should be paid prime attention to, particularly for children. In addition to the 40% geogenic sources, agricultural activities contributed to 30% of the non-carcinogenic risk, whereas mining activities contributed to nearly half of the carcinogenic health risks.
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Affiliation(s)
- Wanjun Jiang
- Tianjin Center, China Geological Survey, Tianjin, 300170, China
- Center of Geoscience Innovation, North China, Tianjin, 300170, China
| | - Lishan Meng
- Tianjin Center, China Geological Survey, Tianjin, 300170, China
- Center of Geoscience Innovation, North China, Tianjin, 300170, China
| | - Futian Liu
- Tianjin Center, China Geological Survey, Tianjin, 300170, China
- Center of Geoscience Innovation, North China, Tianjin, 300170, China
| | - Yizhi Sheng
- Center for Geomicrobiology and Biogeochemistry Research, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, 100083, China.
| | - Sheming Chen
- Tianjin Center, China Geological Survey, Tianjin, 300170, China.
- Center of Geoscience Innovation, North China, Tianjin, 300170, China.
| | - Jilong Yang
- Tianjin Center, China Geological Survey, Tianjin, 300170, China
- Center of Geoscience Innovation, North China, Tianjin, 300170, China
| | - Hairu Mao
- School of Water Resources & Environment, China University of Geosciences, Beijing, 100083, China
| | - Jing Zhang
- Tianjin Center, China Geological Survey, Tianjin, 300170, China
- Center of Geoscience Innovation, North China, Tianjin, 300170, China
| | - Zhuo Zhang
- Tianjin Center, China Geological Survey, Tianjin, 300170, China
- Center of Geoscience Innovation, North China, Tianjin, 300170, China
| | - Hang Ning
- Tianjin Center, China Geological Survey, Tianjin, 300170, China
- Center of Geoscience Innovation, North China, Tianjin, 300170, China
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Chorol L, Gupta SK. Hydrochemical investigation of groundwater in a trans-Himalayan region of Ladakh, India, using geochemical modelling and entropy technique. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:6567-6583. [PMID: 37341892 DOI: 10.1007/s10653-023-01650-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 06/06/2023] [Indexed: 06/22/2023]
Abstract
Evaluating the hydrogeochemistry and groundwater quality status is vital to understand the sources and extent of groundwater contamination. Chemometric analysis, geochemical modelling and entropy technique were explored to delineate the hydrogeochemistry of groundwater in the trans-Himalayan region. Analysis of hydrochemical facies revealed that 57.14, 39.29, and 3.57% of samples were Ca-Mg-HCO3-, Ca-Mg-Cl- and Mg-HCO3- water types, respectively. Gibbs diagrams illustrate the effects of the dissolution of carbonates and silicates during weathering on groundwater hydrogeochemistry. The PHREEQC modelling depicted that most of the secondary minerals are supersaturated except for halite, sylvite, and magnetite which are undersaturated and in equilibrium with nature. Multivariate statistical techniques, including principal component analysis, were applied for source apportionment indicating that the hydrochemistry of the groundwater was mainly controlled by geogenic sources (rock-water interaction) along with secondary pollution through increased anthropogenic sources. Heavy metal accumulation in groundwater depicted the order of Cd > Cr > Mn > Fe > Cu > Ni > Zn. EWQI analysis revealed that none of the samples fell into excellent and good categories. In total, 92.86% of groundwater samples were in an average category while the rest of the samples (7.14%) were unfit for drinking. This study will provide baseline data and a scientific framework which can be used in source apportionment studies, predictive modelling and efficient management of water resources.
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Affiliation(s)
- Lobzang Chorol
- Department of Environmental Science & Engineering, Indian Institute of Technology Indian School of Mines, Dhanbad, 826004, India
| | - Sunil Kumar Gupta
- Department of Environmental Science & Engineering, Indian Institute of Technology Indian School of Mines, Dhanbad, 826004, India.
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Chen X, Wang G, Sheng Y, Liao F, Mao H, Li B, Zhang H, Qiao Z, He J, Liu Y, Lin Y, Yang Y. Nitrogen species and microbial community coevolution along groundwater flowpath in the southwest of Poyang Lake area, China. CHEMOSPHERE 2023; 329:138627. [PMID: 37031839 DOI: 10.1016/j.chemosphere.2023.138627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 04/02/2023] [Accepted: 04/04/2023] [Indexed: 05/03/2023]
Abstract
Nitrate and ammonia overload in groundwater can lead to eutrophication of surface water in areas where surface water is recharged by groundwater. However, this process remained elusive due to the complicated groundwater N cycling, which is governed by the co-evolution of hydrogeochemical conditions and N-cycling microbial communities. Herein, this process was studied along a generalized groundwater flowpath in Ganjing Delta, Poyang Lake area, China. From groundwater recharge to the discharge area near the lake, oxidation-reduction potential (ORP), NO3-N, and NO2-N decreased progressively, while NH3-N, total organic carbon (TOC), Fe2+, sulfide, and TOC/NO3- ratio accumulated in the lakeside samples. The anthropogenic influences such as sewage and agricultural activities drove the nitrate distribution, as observed by Cl- vs. NO3-/Cl- ratio and isotopic composition of nitrate. The hydrogeochemical evolution was intimately coupled with the changes in microbial communities. Variations in microbial community structures was significantly explained by Fe2+, NH3-N, and sulfide, while TOC/NO3- controlled the distribution of predicted N cycling gene. The absence of NH3-N in groundwater upstream was accompanied by the enrichment in Acinetobacter capable of nitrification and aerobic denitrification. These two processes were also supported by Ca2+ + Mg2+ vs. HCO3- ratio and isotopic composition of NO3-. The DNRA process downstream was revealed by both the presence of DNRA-capable microbes such as Arthrobacter and the isotopic composition of NH4+ in environments with high concentrations of NH3-N, TOC/NO3-, Fe2+, and sulfide. This coupled evolution of N cycling and microbial community sheds new light on the N biogeochemical cycle in areas where surface water is recharged by groundwater.
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Affiliation(s)
- Xianglong Chen
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Guangcai Wang
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China.
| | - Yizhi Sheng
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China.
| | - Fu Liao
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Hairu Mao
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Bo Li
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Hongyu Zhang
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Zhiyuan Qiao
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Jiahui He
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Yingxue Liu
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Yilun Lin
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
| | - Ying Yang
- State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing, 100083, PR China; School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, PR China
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Sarma R, Singh SK. Assessment of groundwater quality and human health risks of nitrate and fluoride contamination in a rapidly urbanizing region of India. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:55437-55454. [PMID: 36892698 DOI: 10.1007/s11356-023-26204-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 02/25/2023] [Indexed: 06/18/2023]
Abstract
Groundwater contamination studies are important to understand the risks to public health. In this study, groundwater quality, major ion chemistry, sources of contaminants, and related health risks were evaluated for North-West Delhi, India, a region with a rapidly growing urban population. Groundwater samples collected from the study area were analysed for physicochemical parameters - pH, electrical conductivity, total dissolved solids, total hardness, total alkalinity, carbonate, bicarbonate, chloride, nitrate, sulphate, fluoride, phosphate, calcium, magnesium, sodium and potassium. Investigation of hydrochemical facies revealed that bicarbonate was the dominant anion while magnesium was the dominant cation. Multivariate analysis using principal component analysis and Pearson correlation matrix indicated that major ion chemistry in the aquifer under study is primarily due to mineral dissolution, rock-water interactions and anthropogenic factors. Water quality index values showed that only 20% of the samples were acceptable for drinking. Due to high salinity, 54% of the samples were unfit for irrigation purposes. Nitrate and fluoride concentrations ranged from 0.24 to 380.19 mg/l and 0.05 to 7.90 mg/l, respectively due to fertilizer use, wastewater infiltration and geogenic processes. The health risks from high levels of nitrate and fluoride were calculated for males, females, and children. It was found that health risk from nitrate is more than fluoride in the study region. However, the spatial extent of risk from fluoride is more indicating that more people suffer from fluoride pollution in the study area. The total hazard index for children was found to be more than adults. Continuous monitoring of groundwater and application of remedial measures are recommended to improve the water quality and public health in the region.
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Affiliation(s)
- Riki Sarma
- Department of Environmental Engineering, Delhi Technological University, Delhi, India
| | - Santosh Kumar Singh
- Department of Environmental Engineering, Delhi Technological University, Delhi, India.
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