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Ortmeyer F, Guerreiro MA, Begerow D, Banning A. Modified microbiology through enhanced denitrification by addition of various organic substances-temperature effect. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:60282-60293. [PMID: 37022539 PMCID: PMC10163118 DOI: 10.1007/s11356-023-26784-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 03/29/2023] [Indexed: 05/08/2023]
Abstract
Worldwide, the environmental nitrate (NO3-) problem is increasingly coming into focus. These increases in NO3- concentration result mainly from agricultural inputs and are further exacerbated by decreasing and finite geogenic NO3- degradation capacity in aquifers. Thus, treatment methods are becoming more and more important. In this study, the effects of enhanced denitrification with addition of organic carbon (C) on thereby autochthonous occurring microbiology and compared at room temperature as well as 10 °C were investigated. Incubation of bacteria and fungi was carried out using natural sediments without degradation capacity and groundwater with high NO3- concentrations. Addition of the four applied substrates (acetate, glucose, ascorbic acid, and ethanol) results in major differences in microbial community. Cooling to 10 °C changes the microbiology again. Relative abundances of bacteria are strongly influenced by temperature, which is probably the explanation for different denitrification rates. Fungi are much more sensitive to the milieu change with organic C. Different fungi taxa preferentially occur at one of the two temperature approaches. Major modifications of the microbial community are mainly observed whose denitrification rates strongly depend on the temperature effect. Therefore, we assume a temperature optimum of enhanced denitrification specific to each substrate, which is influenced by the microbiology.
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Affiliation(s)
- Felix Ortmeyer
- Hydrogeology Department, Ruhr-Universität Bochum, Universitätsstraße 150, 44801, Bochum, Germany.
- Geological Survey of Denmark and Greenland, Øster Voldgade 10, 1350 Copenhagen and Universitetsbyen 81, 8000, Aarhus, Denmark.
| | - Marco Alexandre Guerreiro
- Department of Evolution of Plants and Fungi, Ruhr-Universität Bochum, Universitätsstraße 150, 44801, Bochum, Germany
- Environmental Genomics, Christian-Albrechts University of Kiel, Am Botanischen Garten 1-9, 24118, Kiel, Germany
- Max Planck Institute for Evolutionary Biology, August-Thienemann-Str. 2, 24306, Plön, Germany
| | - Dominik Begerow
- Department of Evolution of Plants and Fungi, Ruhr-Universität Bochum, Universitätsstraße 150, 44801, Bochum, Germany
- University of Hamburg, Institute of Plant Sciences and Microbiology, Ohnhorststr. 18, 22609, Hamburg, Germany
| | - Andre Banning
- School of Biological, Earth and Environmental Sciences, University College Cork, Distillery Fields, North Mall, Cork, T23 N73K, Ireland
- University College Cork, Environmental Research Institute, Lee Road, Cork, T23 XE10, Ireland
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2
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Zhao B, Sun Z, Liu Y. An overview of in-situ remediation for nitrate in groundwater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 804:149981. [PMID: 34517309 DOI: 10.1016/j.scitotenv.2021.149981] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 08/19/2021] [Accepted: 08/24/2021] [Indexed: 06/13/2023]
Abstract
Faced with the increasing nitrate pollution in groundwater, in-situ remediation has been widely studied and applied on field-scale as an efficient, economical and less disturbing remediation technology. In this review, we discussed various in-situ remediation for nitrate in groundwater and elaborate on biostimulation, phytoremediation, electrokinetic remediation, permeable reactive barrier and combined remediation. This review described principles of each in-situ remediation, application, the latest progress, problems and challenges on field-scale. Factors affecting the efficiency of in-situ remediation for nitrate in groundwater are also summarized. Finally, this review presented the prospect of in-situ remediation for nitrate pollution in groundwater. The objective of this review is to examine the state of knowledge on in-situ remediation for nitrate in groundwater and critically evaluate factors which affect the up-scaling of laboratory and bench-scale research to field-scale application. This helps to better understand the control mechanisms of various in-situ remediation for nitrate pollution in groundwater and the design options available for application to the field-scale.
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Affiliation(s)
- Bei Zhao
- China University of Geosciences (Beijing), Beijing 100083, China
| | - Zhanxue Sun
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, China.
| | - Yajie Liu
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, China
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Paradis CJ, Miller JI, Moon J, Spencer SJ, Lui LM, Van Nostrand JD, Ning D, Steen AD, McKay LD, Arkin AP, Zhou J, Alm EJ, Hazen TC. Sustained Ability of a Natural Microbial Community to Remove Nitrate from Groundwater. GROUND WATER 2022; 60:99-111. [PMID: 34490626 PMCID: PMC9290691 DOI: 10.1111/gwat.13132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/24/2021] [Accepted: 08/30/2021] [Indexed: 05/23/2023]
Abstract
Microbial-mediated nitrate removal from groundwater is widely recognized as the predominant mechanism for nitrate attenuation in contaminated aquifers and is largely dependent on the presence of a carbon-bearing electron donor. The repeated exposure of a natural microbial community to an electron donor can result in the sustained ability of the community to remove nitrate; this phenomenon has been clearly demonstrated at the laboratory scale. However, in situ demonstrations of this ability are lacking. For this study, ethanol (electron donor) was repeatedly injected into a groundwater well (treatment) for six consecutive weeks to establish the sustained ability of a microbial community to remove nitrate. A second well (control) located upgradient was not injected with ethanol during this time. The treatment well demonstrated strong evidence of sustained ability as evident by ethanol, nitrate, and subsequent sulfate removal up to 21, 64, and 68%, respectively, as compared to the conservative tracer (bromide) upon consecutive exposures. Both wells were then monitored for six additional weeks under natural (no injection) conditions. During the final week, ethanol was injected into both treatment and control wells. The treatment well demonstrated sustained ability as evident by ethanol and nitrate removal up to 20 and 21%, respectively, as compared to bromide, whereas the control did not show strong evidence of nitrate removal (5% removal). Surprisingly, the treatment well did not indicate a sustained and selective enrichment of a microbial community. These results suggested that the predominant mechanism(s) of sustained ability likely exist at the enzymatic- and/or genetic-levels. The results of this study demonstrated the in situ ability of a microbial community to remove nitrate can be sustained in the prolonged absence of an electron donor.
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Affiliation(s)
- Charles J. Paradis
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
| | - John I. Miller
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
- Bredesen CenterUniversity of TennesseeKnoxvilleTN
| | - Ji‐Won Moon
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
| | - Sarah J. Spencer
- Biological Engineering DepartmentMassachusetts Institute of TechnologyCambridgeMA
| | - Lauren M. Lui
- Environmental Genomics and Systems Biology DivisionLawrence Berkeley National LaboratoryBerkeleyCA
| | - Joy D. Van Nostrand
- Institute for Environmental Genomics, Department of Microbiology and Plant Biologyand School of Civil Engineering and Environmental Sciences, University of OklahomaNormanOK
| | - Daliang Ning
- Institute for Environmental Genomics, Department of Microbiology and Plant Biologyand School of Civil Engineering and Environmental Sciences, University of OklahomaNormanOK
| | - Andrew D. Steen
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
- Department of MicrobiologyUniversity of TennesseeKnoxvilleTN
| | - Larry D. McKay
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
| | - Adam P. Arkin
- Environmental Genomics and Systems Biology DivisionLawrence Berkeley National LaboratoryBerkeleyCA
- Department of BioengineeringUniversity of CaliforniaBerkeleyCA
| | - Jizhong Zhou
- Institute for Environmental Genomics, Department of Microbiology and Plant Biologyand School of Civil Engineering and Environmental Sciences, University of OklahomaNormanOK
| | - Eric J. Alm
- Biological Engineering DepartmentMassachusetts Institute of TechnologyCambridgeMA
| | - Terry C. Hazen
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
- Bredesen CenterUniversity of TennesseeKnoxvilleTN
- Department of BioengineeringUniversity of CaliforniaBerkeleyCA
- Department of Civil and Environmental SciencesUniversity of TennesseeKnoxvilleTN
- Center for Environmental BiotechnologyUniversity of TennesseeKnoxvilleTN
- Institute for a Secure and Sustainable EnvironmentUniversity of TennesseeKnoxvilleTN
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4
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Zhang L, Cui B, Yuan B, Zhang A, Feng J, Zhang J, Han X, Pan L, Li L. Denitrification mechanism and artificial neural networks modeling for low-pollution water purification using a denitrification biological filter process. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2020.117918] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Margalef-Marti R, Carrey R, Soler A, Otero N. Evaluating the potential use of a dairy industry residue to induce denitrification in polluted water bodies: A flow-through experiment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 245:86-94. [PMID: 31150913 DOI: 10.1016/j.jenvman.2019.03.086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 03/15/2019] [Accepted: 03/16/2019] [Indexed: 06/09/2023]
Abstract
Improving the effectiveness and economics of strategies to remediate groundwater nitrate pollution is a matter of concern. In this context, the addition of whey into aquifers could provide a feasible solution to attenuate nitrate contamination by inducing heterotrophic denitrification, while recycling an industry residue. Before its application, the efficacy of the treatment must be studied at laboratory-scale to optimize the application strategy in order to avoid the generation of harmful intermediate compounds. To do this, a flow-through denitrification experiment using whey as organic C source was performed, and different C/N ratios and injection periodicities were tested. The collected samples were analyzed to determine the chemical and isotopic composition of N and C compounds. The results proved that whey could promote denitrification. Nitrate was completely removed when using either a 3.0 or 2.0 C/N ratio. However, daily injection with C/N ratios from 1.25 to 1.5 seemed advantageous, since this strategy decreased nitrate concentration to values below the threshold for water consumption while avoiding nitrite accumulation and whey release with the outflow. The isotopic results confirmed that nitrate attenuation was due to denitrification and that the production of DIC was related to bacterial whey oxidation. Furthermore, the isotopic data suggested that when denitrification was not complete, the outflow could present a mix of denitrified and nondenitrified water. The calculated isotopic fractionation values (ε15NNO3/N2 and ε18ONO3/N2) might be applied in the future to quantify the efficiency of the bioremediation treatments by whey application at field-scale.
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Affiliation(s)
- Rosanna Margalef-Marti
- Grup MAiMA, SGR Mineralogia Aplicada, Geoquímica I Geomicrobiologia, Departament de Mineralogia, Petrologia I Geologia Aplicada, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), Barcelona, Spain.
| | - Raúl Carrey
- Grup MAiMA, SGR Mineralogia Aplicada, Geoquímica I Geomicrobiologia, Departament de Mineralogia, Petrologia I Geologia Aplicada, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), Barcelona, Spain
| | - Albert Soler
- Grup MAiMA, SGR Mineralogia Aplicada, Geoquímica I Geomicrobiologia, Departament de Mineralogia, Petrologia I Geologia Aplicada, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), Barcelona, Spain
| | - Neus Otero
- Grup MAiMA, SGR Mineralogia Aplicada, Geoquímica I Geomicrobiologia, Departament de Mineralogia, Petrologia I Geologia Aplicada, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), Barcelona, Spain; Serra Húnter Fellowship, Generalitat de Catalunya, Spain
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Chen D, Gu X, Zhu W, He S, Huang J, Zhou W. Electrons transfer determined greenhouse gas emissions in enhanced nitrogen-removal constructed wetlands with different carbon sources and carbon-to-nitrogen ratios. BIORESOURCE TECHNOLOGY 2019; 285:121313. [PMID: 30959388 DOI: 10.1016/j.biortech.2019.121313] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 03/30/2019] [Accepted: 04/01/2019] [Indexed: 06/09/2023]
Abstract
A constructed wetland (CW) was established to explore the influence of carbon addition (glucose or sodium acetate) on nitrogen removal and greenhouse gas (GHG) emissions at chemical oxygen demand to nitrogen ratios (COD/Ns) of 0, 4, 7. Results showed that the type of carbon source and COD/N significantly influenced the CW performance, in which the electrons transfer determined the regulation of denitrification, methanogenesis and respiration. Higher N2O emissions were consistent with higher nitrite accumulation at low COD/N because of electrons competition. The residual carbon source after near-complete denitrification could be further utilized by methanogenesis. Sodium acetate was superior to glucose in promoting denitrification and reducing global warming potential (GWP). In addition, bacteria sequencing and functional genes confirmed the important role of the type of carbon source on controlling nitrogen removal, carbon consumption and GHG emissions in microbial communities.
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Affiliation(s)
- Danyue Chen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Xushun Gu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Wenying Zhu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China; Department of Environmental Systems Science, Swiss Federal Institute of Technology (ETH) Zurich, 8092 Zurich, Switzerland
| | - Shengbing He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
| | - Jungchen Huang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Weili Zhou
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
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Silver M, Selke S, Balsaa P, Wefer-Roehl A, Kübeck C, Schüth C. Fate of five pharmaceuticals under different infiltration conditions for managed aquifer recharge. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 642:914-924. [PMID: 29929143 DOI: 10.1016/j.scitotenv.2018.06.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 06/09/2018] [Accepted: 06/10/2018] [Indexed: 06/08/2023]
Abstract
Infiltration of treated wastewater (TWW) to recharge depleted aquifers, often referred to as managed aquifer recharge, is a solution to replenish groundwater resources in regions facing water scarcity. We present a mass balance approach to infer the amounts of five pharmaceuticals (carbamazepine, diclofenac, fenoprofen, gemfibrozil, and naproxen) degraded in column experiments based on concentrations of pharmaceuticals in the aqueous and solid (sorbed) phases. Column experiments were conducted under three different conditions: continuous infiltration, wetting and drying cycles, and wetting and drying cycles with elevated concentrations of antibiotics (which may reduce microbially aided degradation of other compounds). A mass balance comparing pharmaceutical mass in the water phase over the 16-month duration of the experiments to mass sorbed to the soil was used to infer the mass of pharmaceuticals degraded. Results show sorption as the main attenuation mechanism for carbamazepine. About half of the mass of diclofenac was degraded with wetting and drying cycles, but no significant degradation was found for continuous infiltration, while 32% of infiltrated mass sorbed. Fenoprofen was degraded in the shallow and aerobic part of the soil, but degradation appeared to cease beyond 27 cm depth. Gemfibrozil attenuated through a combination of degradation and sorption, with slight increases in attenuation with depth from both mechanisms. Naproxen degraded progressively with depth, resulting in attenuation of >90% of the mass. In the column with elevated concentrations of antibiotics, the antibiotics attenuated to about 50% or less of inflow concentrations by 27 cm depth and within this zone, less degradation of the other compounds was observed.
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Affiliation(s)
- Matthew Silver
- Institute of Applied Geosciences, Technische Universität Darmstadt, Darmstadt, Germany; Water Resources Management Division, IWW Water Centre, Mülheim an der Ruhr, Germany.
| | - Stephanie Selke
- Water Quality Division, IWW Water Centre, Mülheim an der Ruhr, Germany
| | - Peter Balsaa
- Water Quality Division, IWW Water Centre, Mülheim an der Ruhr, Germany.
| | - Annette Wefer-Roehl
- Institute of Applied Geosciences, Technische Universität Darmstadt, Darmstadt, Germany
| | - Christine Kübeck
- Water Resources Management Division, IWW Water Centre, Mülheim an der Ruhr, Germany.
| | - Christoph Schüth
- Institute of Applied Geosciences, Technische Universität Darmstadt, Darmstadt, Germany; Water Resources Management Division, IWW Water Centre, Mülheim an der Ruhr, Germany.
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Carrey R, Rodríguez-Escales P, Soler A, Otero N. Tracing the role of endogenous carbon in denitrification using wine industry by-product as an external electron donor: Coupling isotopic tools with mathematical modeling. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 207:105-115. [PMID: 29154003 DOI: 10.1016/j.jenvman.2017.10.063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 10/26/2017] [Accepted: 10/28/2017] [Indexed: 06/07/2023]
Abstract
Nitrate removal through enhanced biological denitrification (EBD), consisting of the inoculation of an external electron donor, is a feasible solution for the recovery of groundwater quality. In this context, liquid waste from wine industries (wine industry by-products, WIB) may be feasible for use as a reactant to enhance heterotrophic denitrification. To address the feasibility of WIB as electron donor to promote denitrification, as well as to evaluate the role of biomass as a secondary organic C source, a flow-through experiment was carried out. Chemical and isotopic characterization was performed and coupled with mathematical modeling. Complete nitrate attenuation with no nitrite accumulation was successfully achieved after 10 days. Four different C/N molar ratios (7.0, 2.0, 1.0 and 0) were tested. Progressive decrease of the C/N ratio reduced the remaining C in the outflow and favored biomass migration, producing significant changes in dispersivity in the reactor, which favored efficient nitrate degradation. The applied mathematical model described the general trends for nitrate, ethanol, dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) concentrations. This model shows how the biomass present in the system is degraded to dissolved organic C (DOCen) and becomes the main source of DOC for a C/N ratio between 1.0 and 0. The isotopic model developed for organic and inorganic carbon also describes the general trends of δ13C of ethanol, DOC and DIC in the outflow water. The study of the evolution of the isotopic fractionation of organic C using a Rayleigh distillation model shows the shift in the organic carbon source from the WIB to the biomass and is in agreement with the isotopic fractionation values used to calibrate the model. Isotopic fractionations (ε) of C-ethanol and C-DOCen were -1‰ and -5‰ (model) and -3.3‰ and -4.8‰ (Rayleigh), respectively. In addition, an inverse isotopic fractionation of +10‰ was observed for biomass degradation to DOCen. Overall, WIB can efficiently promote nitrate reduction in EBD treatments. The conceptual model of the organic C cycle and the developed mathematical model accurately described the chemical and isotopic transformations that occur during this induced denitrification.
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Affiliation(s)
- R Carrey
- Grup d'Mineralogia Aplicada i Medi Ambient, Dep. Mineralogia, Petrologia i Geologia Aplicada, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), C/ Martí i Franquès s/n, 08028, Barcelona, Spain.
| | - P Rodríguez-Escales
- Dept. of Civil and Environmental Engineering, Universitat Politècnica de Catalunya, Jordi Girona 1-3, 08034 Barcelona, Spain; Associated Unit: Hydrogeology Group (UPC-CSIC), Spain
| | - A Soler
- Grup d'Mineralogia Aplicada i Medi Ambient, Dep. Mineralogia, Petrologia i Geologia Aplicada, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), C/ Martí i Franquès s/n, 08028, Barcelona, Spain
| | - N Otero
- Grup d'Mineralogia Aplicada i Medi Ambient, Dep. Mineralogia, Petrologia i Geologia Aplicada, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), C/ Martí i Franquès s/n, 08028, Barcelona, Spain; Serra Hunter Fellowship, Generalitat de Catalunya, Spain
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Grau-Martínez A, Torrentó C, Carrey R, Rodríguez-Escales P, Domènech C, Ghiglieri G, Soler A, Otero N. Feasibility of two low-cost organic substrates for inducing denitrification in artificial recharge ponds: Batch and flow-through experiments. JOURNAL OF CONTAMINANT HYDROLOGY 2017; 198:48-58. [PMID: 28131436 DOI: 10.1016/j.jconhyd.2017.01.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 01/16/2017] [Accepted: 01/17/2017] [Indexed: 06/06/2023]
Abstract
Anaerobic batch and flow-through experiments were performed to assess the capacity of two organic substrates to promote denitrification of nitrate-contaminated groundwater within managed artificial recharge systems (MAR) in arid or semi-arid regions. Denitrification in MAR systems can be achieved through artificial recharge ponds coupled with a permeable reactive barrier in the form of a reactive organic layer. In arid or semi-arid regions, short-term efficient organic substrates are required due to the short recharge periods. We examined the effectiveness of two low-cost, easily available and easily handled organic substrates, commercial plant-based compost and crushed palm tree leaves, to determine the feasibility of using them in these systems. Chemical and multi-isotopic monitoring (δ15NNO3, δ18ONO3, δ34SSO4, δ18OSO4) of the laboratory experiments confirmed that both organic substrates induced denitrification. Complete nitrate removal was achieved in all the experiments with a slight transient nitrite accumulation. In the flow-through experiments, ammonium release was observed at the beginning of both experiments and lasted longer for the experiment with palm tree leaves. Isotopic characterisation of the released ammonium suggested ammonium leaching from both organic substrates at the beginning of the experiments and pointed to ammonium production by DNRA for the palm tree leaves experiment, which would only account for a maximum of 15% of the nitrate attenuation. Sulphate reduction was achieved in both column experiments. The amount of organic carbon consumed during denitrification and sulphate reduction was 0.8‰ of the total organic carbon present in commercial compost and 4.4% for the palm tree leaves. The N and O isotopic fractionation values obtained (εN and εO) were -10.4‰ and -9.0‰ for the commercial compost (combining data from both batch and column experiments), and -9.9‰ and -8.6‰ for the palm tree column, respectively. Both materials showed a satisfactory capacity for denitrification, but the palm tree leaves gave a higher denitrification rate and yield (amount of nitrate consumed per amount of available C) than commercial compost.
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Affiliation(s)
- Alba Grau-Martínez
- Grup de Mineralogia Aplicada i Geoquímica de Fluids, Departament de Mineralogia, Petrologia i Geologia Aplicada, SIMGEO UB-CSIC, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), C/ Martí i Franquès, s/n, 08028 Barcelona, Spain.
| | - Clara Torrentó
- Grup de Mineralogia Aplicada i Geoquímica de Fluids, Departament de Mineralogia, Petrologia i Geologia Aplicada, SIMGEO UB-CSIC, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), C/ Martí i Franquès, s/n, 08028 Barcelona, Spain; Centre for Hydrogeology and Geothermics, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
| | - Raúl Carrey
- Grup de Mineralogia Aplicada i Geoquímica de Fluids, Departament de Mineralogia, Petrologia i Geologia Aplicada, SIMGEO UB-CSIC, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), C/ Martí i Franquès, s/n, 08028 Barcelona, Spain
| | - Paula Rodríguez-Escales
- Hydrogeology Group (GHS), Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya (UPC), c/Jordi Girona 1-3, 08034 Barcelona, Spain
| | - Cristina Domènech
- Grup de Mineralogia Aplicada i Geoquímica de Fluids, Departament de Mineralogia, Petrologia i Geologia Aplicada, SIMGEO UB-CSIC, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), C/ Martí i Franquès, s/n, 08028 Barcelona, Spain
| | - Giorgio Ghiglieri
- Department of Chemical and Geological Sciences, University of Cagliari, Via Trentino 51, 09127 Cagliari, Italy; Desertification Research Center-NRD, University of Sassari, Viale Italia 39, 07100 Sassari, Italy
| | - Albert Soler
- Grup de Mineralogia Aplicada i Geoquímica de Fluids, Departament de Mineralogia, Petrologia i Geologia Aplicada, SIMGEO UB-CSIC, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), C/ Martí i Franquès, s/n, 08028 Barcelona, Spain
| | - Neus Otero
- Grup de Mineralogia Aplicada i Geoquímica de Fluids, Departament de Mineralogia, Petrologia i Geologia Aplicada, SIMGEO UB-CSIC, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), C/ Martí i Franquès, s/n, 08028 Barcelona, Spain
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