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Deb S, Lewicka-Szczebak D, Rohe L. Microbial nitrogen transformations tracked by natural abundance isotope studies and microbiological methods: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:172073. [PMID: 38554959 DOI: 10.1016/j.scitotenv.2024.172073] [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: 01/03/2024] [Revised: 03/07/2024] [Accepted: 03/27/2024] [Indexed: 04/02/2024]
Abstract
Nitrogen is an essential nutrient in the environment that exists in multiple oxidation states in nature. Numerous microbial processes are involved in its transformation. Knowledge about very complex N cycling has been growing rapidly in recent years, with new information about associated isotope effects and about the microbes involved in particular processes. Furthermore, molecular methods that are able to detect and quantify particular processes are being developed, applied and combined with other analytical approaches, which opens up new opportunities to enhance understanding of nitrogen transformation pathways. This review presents a summary of the microbial nitrogen transformation, including the respective isotope effects of nitrogen and oxygen on different nitrogen-bearing compounds (including nitrates, nitrites, ammonia and nitrous oxide), and the microbiological characteristics of these processes. It is supplemented by an overview of molecular methods applied for detecting and quantifying the activity of particular enzymes involved in N transformation pathways. This summary should help in the planning and interpretation of complex research studies applying isotope analyses of different N compounds and combining microbiological and isotopic methods in tracking complex N cycling, and in the integration of these results in modelling approaches.
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Affiliation(s)
- Sushmita Deb
- Institute of Geological Sciences, University of Wrocław, pl. M. Borna 9, 50-204 Wrocław, Poland
| | | | - Lena Rohe
- Thünen Institute of Climate-Smart Agriculture, Bundesallee 65, 38116 Braunschweig, Germany
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2
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Gallarotti N, Barthel M, Verhoeven E, Pereira EIP, Bauters M, Baumgartner S, Drake TW, Boeckx P, Mohn J, Longepierre M, Mugula JK, Makelele IA, Ntaboba LC, Six J. In-depth analysis of N 2O fluxes in tropical forest soils of the Congo Basin combining isotope and functional gene analysis. THE ISME JOURNAL 2021; 15:3357-3374. [PMID: 34035444 PMCID: PMC8528805 DOI: 10.1038/s41396-021-01004-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 04/14/2021] [Accepted: 04/30/2021] [Indexed: 02/04/2023]
Abstract
Primary tropical forests generally exhibit large gaseous nitrogen (N) losses, occurring as nitric oxide (NO), nitrous oxide (N2O) or elemental nitrogen (N2). The release of N2O is of particular concern due to its high global warming potential and destruction of stratospheric ozone. Tropical forest soils are predicted to be among the largest natural sources of N2O; however, despite being the world's second-largest rainforest, measurements of gaseous N-losses from forest soils of the Congo Basin are scarce. In addition, long-term studies investigating N2O fluxes from different forest ecosystem types (lowland and montane forests) are scarce. In this study we show that fluxes measured in the Congo Basin were lower than fluxes measured in the Neotropics, and in the tropical forests of Australia and South East Asia. In addition, we show that despite different climatic conditions, average annual N2O fluxes in the Congo Basin's lowland forests (0.97 ± 0.53 kg N ha-1 year-1) were comparable to those in its montane forest (0.88 ± 0.97 kg N ha-1 year-1). Measurements of soil pore air N2O isotope data at multiple depths suggests that a microbial reduction of N2O to N2 within the soil may account for the observed low surface N2O fluxes and low soil pore N2O concentrations. The potential for microbial reduction is corroborated by a significant abundance and expression of the gene nosZ in soil samples from both study sites. Although isotopic and functional gene analyses indicate an enzymatic potential for complete denitrification, combined gaseous N-losses (N2O, N2) are unlikely to account for the missing N-sink in these forests. Other N-losses such as NO, N2 via Feammox or hydrological particulate organic nitrogen export could play an important role in soils of the Congo Basin and should be the focus of future research.
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Affiliation(s)
- Nora Gallarotti
- grid.5801.c0000 0001 2156 2780Department of Environmental Systems Science, Swiss Federal Institute of Technology, ETH Zurich, Zurich, Switzerland
| | - Matti Barthel
- grid.5801.c0000 0001 2156 2780Department of Environmental Systems Science, Swiss Federal Institute of Technology, ETH Zurich, Zurich, Switzerland
| | - Elizabeth Verhoeven
- grid.4391.f0000 0001 2112 1969College of Agricultural Sciences, Oregon State University, Corvallis, OR USA
| | - Engil Isadora Pujol Pereira
- grid.449717.80000 0004 5374 269XSchool of Earth, Environmental, and Marine Sciences, University of Texas Rio Grande Valley, Edinburg, TX USA
| | - Marijn Bauters
- grid.5342.00000 0001 2069 7798Isotope Bioscience Laboratory, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium ,grid.5342.00000 0001 2069 7798Computational and Applied Vegetation Ecology Lab, Department of Environment, Ghent University, Ghent, Belgium
| | - Simon Baumgartner
- grid.5801.c0000 0001 2156 2780Department of Environmental Systems Science, Swiss Federal Institute of Technology, ETH Zurich, Zurich, Switzerland ,grid.7942.80000 0001 2294 713XEarth and Life Institute, Université Catholique de Louvain, Louvain, Belgium
| | - Travis W. Drake
- grid.5801.c0000 0001 2156 2780Department of Environmental Systems Science, Swiss Federal Institute of Technology, ETH Zurich, Zurich, Switzerland
| | - Pascal Boeckx
- grid.5342.00000 0001 2069 7798Isotope Bioscience Laboratory, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Joachim Mohn
- grid.7354.50000 0001 2331 3059Laboratory for Air Pollution/Environmental Technology, Swiss Federal Laboratories of Materials Science and Technology, Empa Dubendorf, Switzerland
| | - Manon Longepierre
- grid.5801.c0000 0001 2156 2780Department of Environmental Systems Science, Swiss Federal Institute of Technology, ETH Zurich, Zurich, Switzerland
| | - John Kalume Mugula
- grid.442836.f0000 0004 7477 7760Département de Biologie, Université Officielle de Bukavu, Bukavu, Democratic Republic of Congo
| | - Isaac Ahanamungu Makelele
- grid.442836.f0000 0004 7477 7760Département de Biologie, Université Officielle de Bukavu, Bukavu, Democratic Republic of Congo ,grid.5342.00000 0001 2069 7798Department of Green Chemistry and Technology, Ghent University, Ghent, Belgium
| | - Landry Cizungu Ntaboba
- grid.442834.d0000 0004 6011 4325Département d’ Agronomie, Université Catholique de Bukavu, Bukavu, Democratic Republic of Congo
| | - Johan Six
- grid.5801.c0000 0001 2156 2780Department of Environmental Systems Science, Swiss Federal Institute of Technology, ETH Zurich, Zurich, Switzerland
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3
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Bracken CJ, Lanigan GJ, Richards KG, Müller C, Tracy SR, Grant J, Krol DJ, Sheridan H, Lynch MB, Grace C, Fritch R, Murphy PNC. Source partitioning using N 2O isotopomers and soil WFPS to establish dominant N 2O production pathways from different pasture sward compositions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 781:146515. [PMID: 33812119 DOI: 10.1016/j.scitotenv.2021.146515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 03/11/2021] [Accepted: 03/11/2021] [Indexed: 06/12/2023]
Abstract
Nitrous oxide (N2O) is a potent greenhouse gas (GHG) emitted from agricultural soils and is influenced by nitrogen (N) fertiliser management and weather and soil conditions. Source partitioning N2O emissions related to management practices and soil conditions could suggest effective mitigation strategies. Multispecies swards can maintain herbage yields at reduced N fertiliser rates compared to grass monocultures and may reduce N losses to the wider environment. A restricted-simplex centroid experiment was used to measure daily N2O fluxes and associated isotopomers from eight experimental plots (7.8 m2) post a urea-N fertiliser application (40 kg N ha-1). Experimental pastures consisted of differing proportions of grass, legume and forage herb represented by perennial ryegrass (Lolium perenne), white clover (Trifolium repens) and ribwort plantain (Plantago lanceolata), respectively. N2O isotopomers were measured using a cavity ring down spectroscopy (CRDS) instrument adapted with a small sample isotope module (SSIM) for the analysis of gas samples ≤20 mL. Site preference (SP = δ15Nα - δ15Nβ) and δ15Nbulk ((δ15Nα + δ15Nβ) / 2) values were used to attribute N2O production to nitrification, denitrification or a mixture of both nitrification and denitrification over a range of soil WFPS (%). Daily N2O fluxes ranged from 8.26 to 86.86 g N2O-N ha-1 d-1. Overall, 34.2% of daily N2O fluxes were attributed to nitrification, 29.0% to denitrification and 36.8% to a mixture of both. A significant diversity effect of white clover and ribwort plantain on predicted SP and δ15Nbulk indicated that the inclusion of ribwort plantain may decrease N2O emission through biological nitrification inhibition under drier soil conditions (31%-75% WFPS). Likewise, a sharp decline in predicted SP indicates that increased white clover content could increase N2O emissions associated with denitrification under elevated soil moisture conditions (43%-77% WFPS). Biological nitrification inhibition from ribwort plantain inclusion in grassland swards and management of N fertiliser source and application timing to match soil moisture conditions could be useful N2O mitigation strategies.
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Affiliation(s)
- Conor J Bracken
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland; UCD Earth Institute, University College Dublin, Belfield, Dublin 4, Ireland; Teagasc, Environmental Research Center, Johnstown Castle, Wexford, Ireland
| | - Gary J Lanigan
- Teagasc, Environmental Research Center, Johnstown Castle, Wexford, Ireland
| | - Karl G Richards
- Teagasc, Environmental Research Center, Johnstown Castle, Wexford, Ireland
| | - Christoph Müller
- UCD Earth Institute, University College Dublin, Belfield, Dublin 4, Ireland; Institute of Plant Ecology, Justus-Liebig University, Heinrich-Buff-Ring 26, 35392 Giessen, Germany; UCD School of Biology and Environmental Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Saoirse R Tracy
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland; UCD Earth Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - James Grant
- Teagasc Food Research Center Ashtown, Dublin 15, Ireland
| | - Dominika J Krol
- Teagasc, Environmental Research Center, Johnstown Castle, Wexford, Ireland
| | - Helen Sheridan
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland; UCD Lyons Farm, Lyons Estate, Celbridge, Naas, Co. Kildare, Ireland
| | - Mary Bridget Lynch
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland; UCD Lyons Farm, Lyons Estate, Celbridge, Naas, Co. Kildare, Ireland
| | - Cornelia Grace
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland; UCD Lyons Farm, Lyons Estate, Celbridge, Naas, Co. Kildare, Ireland
| | - Rochelle Fritch
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland; UCD Lyons Farm, Lyons Estate, Celbridge, Naas, Co. Kildare, Ireland
| | - Paul N C Murphy
- UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland; UCD Earth Institute, University College Dublin, Belfield, Dublin 4, Ireland.
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Zhang P, Wen T, Hu Y, Zhang J, Cai Z. Can N Fertilizer Addition Affect N 2O Isotopocule Signatures for Soil N 2O Source Partitioning? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18095024. [PMID: 34068614 PMCID: PMC8126104 DOI: 10.3390/ijerph18095024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 04/22/2021] [Accepted: 04/27/2021] [Indexed: 11/24/2022]
Abstract
Isotopocule signatures of N2O (δ15Nbulk, δ18O and site preference) are useful for discerning soil N2O source, but sometimes, N fertilizer is needed to ensure that there is
enough N2O flux for accurate isotopocule measurements. However, whether fertilizer affects these measurements is unknown. This study evaluated a gradient of NH4NO3 addition on N2O productions and isotopocule values in two acidic subtropical soils. The results showed that N2O production rates obviously amplified with increasing NH4NO3 (p < 0.01), although a lower N2O production rate and an increasing extent appeared in forest soil. The δ15Nbulk of N2O produced in forest soil was progressively enriched when more NH4NO3 was added, while becoming
more depleted of agricultural soil. Moreover, the N2O site
preference (SP) values collectively elevated with increasing NH4NO3 in both soils, indicating that N2O contributions changed. The increased N2O production in agricultural soil was predominantly due to the added NH4NO3 via autotrophic nitrification and fungal denitrification (beyond 50%), which significantly
increased with added
NH4NO3, whereas soil organic nitrogen contributed most to N2O production in forest soil, probably via heterotrophic nitrification. Lacking the characteristic
SP
of heterotrophic nitrification,
its
N2O contribution
change
cannot be accurately identified yet. Overall, N fertilizer should be applied strictly according to the field application rate or N deposition amount when using isotopocule signatures to estimate soil N2O processes.
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Affiliation(s)
- Peiyi Zhang
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; (P.Z.); (Y.H.); (J.Z.); (Z.C.)
| | - Teng Wen
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; (P.Z.); (Y.H.); (J.Z.); (Z.C.)
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China
- Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, China
- Correspondence: ; Tel.: +86-25-8589-1203
| | - Yangmei Hu
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; (P.Z.); (Y.H.); (J.Z.); (Z.C.)
| | - Jinbo Zhang
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; (P.Z.); (Y.H.); (J.Z.); (Z.C.)
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China
- Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, China
| | - Zucong Cai
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; (P.Z.); (Y.H.); (J.Z.); (Z.C.)
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China
- Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, China
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5
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Stuchiner ER, Weller ZD, von Fischer JC. An approach for calibrating laser-based N 2 O isotopic analyzers for soil biogeochemistry research. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2021; 35:e8978. [PMID: 33053257 DOI: 10.1002/rcm.8978] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 10/11/2020] [Accepted: 10/13/2020] [Indexed: 06/11/2023]
Abstract
RATIONALE Technological advances have motivated researchers to transition from traditional gas chromatography/isotope ratio mass spectrometry to rapid, high-throughput, laser-based instrumentation for N2 O isotopic research. However, calibrating laser-based instruments to yield accurate and precise isotope ratios has been an ongoing challenge. To streamline the N2 O isotope research pipeline, we developed the calibration protocol for laser-based analyzers described here. While our approach is targeted at laboratory soil incubations, we anticipate that it will be broadly applicable for diverse types of stable isotope research. METHODS We prepared standards diluted from USGS52 and from a commercial cylinder to develop a calibration curve spanning from 0.3 to 300 ppm N2 O. To calibrate over this broad range, we binned each isotopocule (N2 O, N15 NO, 15 NNO, and NN18 O) into low, medium, and high concentration ranges and then used mathematically similar polynomial functions to calibrate the isotopocules within each concentration range. We also assessed the temporal stability of the instrument and the capacity for our calibration approach to work with isotopically enriched gas samples. RESULTS Our calibration approach yielded generally accurate and precise data when isotopocules were calibrated in concentration ranges, and the measurements appeared to be temporally stable. For all isotopocules at natural abundance, the residual percentage error was smallest in the medium N2 O range. There was more noise in the corrected isotopomers and isotopologue at natural abundance in samples with the lowest and highest N2 O concentrations. Corrected isotopomer results from isotopically enriched samples were very precise. CONCLUSIONS Developing our calibration strategy involved learning several key lessons: (1) calibrate isotopocules in distinct concentration ranges, (2) use mathematically similar models to calibrate the isotopocules in each range, (3) calibrated N2 O concentrations and δ values tend to be most accurate and precise in the medium N2 O range, and (4) we encourage users to take advantage of isotopic enrichment to capitalize on laser-based instrument strengths.
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Affiliation(s)
- Emily R Stuchiner
- Department of Biology, Colorado State University Fort Collins, CO, 80523, USA
- Graduate Degree Program in Ecology, Colorado State University Fort Collins, CO, 80523, USA
| | - Zachary D Weller
- Department of Statistics, Colorado State University Fort Collins, CO, 80523, USA
| | - Joseph C von Fischer
- Department of Biology, Colorado State University Fort Collins, CO, 80523, USA
- Graduate Degree Program in Ecology, Colorado State University Fort Collins, CO, 80523, USA
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6
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Sena‐Souza JP, Houlton BZ, Martinelli LA, Bielefeld Nardoto G. Reconstructing continental‐scale variation in soil δ
15
N: a machine learning approach in South America. Ecosphere 2020. [DOI: 10.1002/ecs2.3223] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Affiliation(s)
- João Paulo Sena‐Souza
- Programa de Pós‐Graduação em Ciências Ambientais Universidade de Brasília (UnB) Campus de Planaltina Planaltina Distrito Federal73345‐010Brazil
- Departamento de Geociências Universidade Estadual de Montes Claros (Unimontes) Campus Professor Darcy Ribeiro Montes Claros Minas Gerais39401‐089Brazil
| | - Benjamin Z. Houlton
- Department of Land, Air and Water Resources University of California Davis California95616USA
| | - Luiz Antônio Martinelli
- Departamento de Ecologia Isotópica Centro de Energia Nuclear da Agricultura (CENA) Universidade de São Paulo (USP) Campus de Piracicaba Piracicaba São Paulo13416‐000Brazil
| | - Gabriela Bielefeld Nardoto
- Departamento de Ecologia Instituto de Ciências Biológicas Universidade de Brasília (UnB) Campus Universitário Darcy Ribeiro, Asa Norte Brasília Distrito Federal70910‐900Brazil
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7
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Natural Nitrogen Isotope Ratios as a Potential Indicator of N2O Production Pathways in a Floodplain Fen. WATER 2020. [DOI: 10.3390/w12020409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Nitrous oxide (N2O), a major greenhouse gas and ozone depleter, is emitted from drained organic soils typically developed in floodplains. We investigated the effect of the water table depth and soil oxygen (O2) content on N2O fluxes and their nitrogen isotope composition in a drained floodplain fen in Estonia. Measurements were done at natural water table depth, and we created a temporary anoxic environment by experimental flooding. From the suboxic peat (0.5–6 mg O2/L) N2O emissions peaked at 6 mg O2/L and afterwards decreased with decreasing O2. From the anoxic and oxic peat (0 and >6 mg O2/L, respectively) N2O emissions were low. Under anoxic conditions the δ15N/δ14N ratio of the top 10 cm peat layer was low, gradually decreasing to 30 cm. In the suboxic peat, δ15N/δ14N ratios increased with depth. In samples of peat fluctuating between suboxic and anoxic, the elevated 15N/14N ratios (δ15N = 7–9‰ ambient N2) indicated intensive microbial processing of nitrogen. Low values of site preference (SP; difference between the central and peripheral 15N atoms) and δ18O-N2O in the captured gas samples indicate nitrifier denitrification in the floodplain fen.
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8
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Li Q, Wang F, Yu Q, Yan W, Li X, Lv S. Dominance of nitrous oxide production by nitrification and denitrification in the shallow Chaohu Lake, Eastern China: Insight from isotopic characteristics of dissolved nitrous oxide. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 255:113212. [PMID: 31542667 DOI: 10.1016/j.envpol.2019.113212] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 08/05/2019] [Accepted: 09/06/2019] [Indexed: 06/10/2023]
Abstract
In recent decades, most lakes in Eastern China have suffered unprecedented nitrogen pollution, making them potential "hotspots" for N2O production and emission. Understanding the mechanisms of N2O production and quantifying emissions in these lakes is essential for assessing regional and global N2O budgets and for mitigating N2O emissions. Here, we measure isotopic compositions (δ15N-N2O and δ18O-N2O) and site preference (SP) of dissolved N2O in an attempt to differentiate the relative contribution of N2O production processes in the shallow, eutrophic Chaohu Lake, Eastern China. Our results show that the bulk isotope ratios for δ15N-N2O, δ18O-N2O, and SP were 5.8 ± 3.9‰, 29.3 ± 13.4‰, and 18.6 ± 3.2‰, respectively. More than 76.8% of the dissolved N2O was produced via microbial processes. Findings suggest that dissolved N2O is primarily produced via nitrification (between 27.3% and 48.0%) and denitrification (between 31.9% and 49.5%). In addition, isotopic data exhibit significant N2O consumption during denitrification. We estimate the average N2O emission rate (27.5 ± 26.0 μg N m-2 h-1), which is higher than that from rivers in the Changjiang River network (CRN). We scaled-up the regional N2O emission (from 1.98 Gg N yr-1 to 4.58 Gg N yr-1) using a N2O emission factor (0.51 ± 0.63%) for shallow lakes in the middle and lower region of the CRN. We suggest that beneficial circumstances for promoting complete denitrification may be helpful for reducing N2O production and emissions in fresh surface waters.
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Affiliation(s)
- Qingqian Li
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Fang Wang
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
| | - Qibiao Yu
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
| | - Weijin Yan
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
| | - Xinyan Li
- Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China.
| | - Shucong Lv
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
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9
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Stable Isotopes in Greenhouse Gases from Soil: A Review of Theory and Application. ATMOSPHERE 2019. [DOI: 10.3390/atmos10070377] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Greenhouse gases emitted from soil play a crucial role in the atmospheric environment and global climate change. The theory and technique of detecting stable isotopes in the atmosphere has been widely used to an investigate greenhouse gases from soil. In this paper, we review the current literature on greenhouse gases emitted from soil, including carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). We attempt to synthesize recent advances in the theory and application of stable isotopes in greenhouse gases from soil and discuss future research needs and directions.
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10
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Castellano‐Hinojosa A, Loick N, Dixon E, Matthews GP, Lewicka‐Szczebak D, Well R, Bol R, Charteris A, Cardenas L. Improved isotopic model based on 15 N tracing and Rayleigh-type isotope fractionation for simulating differential sources of N 2 O emissions in a clay grassland soil. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33:449-460. [PMID: 30561863 PMCID: PMC6492082 DOI: 10.1002/rcm.8374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 12/12/2018] [Accepted: 12/12/2018] [Indexed: 06/09/2023]
Abstract
RATIONALE Isotopic signatures of N2 O can help distinguish between two sources (fertiliser N or endogenous soil N) of N2 O emissions. The contribution of each source to N2 O emissions after N-application is difficult to determine. Here, isotopologue signatures of emitted N2 O are used in an improved isotopic model based on Rayleigh-type equations. METHODS The effects of a partial (33% of surface area, treatment 1c) or total (100% of surface area, treatment 3c) dispersal of N and C on gaseous emissions from denitrification were measured in a laboratory incubation system (DENIS) allowing simultaneous measurements of NO, N2 O, N2 and CO2 over a 12-day incubation period. To determine the source of N2 O emissions those results were combined with both the isotope ratio mass spectrometry analysis of the isotopocules of emitted N2 O and those from the 15 N-tracing technique. RESULTS The spatial dispersal of N and C significantly affected the quantity, but not the timing, of gas fluxes. Cumulative emissions are larger for treatment 3c than treatment 1c. The 15 N-enrichment analysis shows that initially ~70% of the emitted N2 O derived from the applied amendment followed by a constant decrease. The decrease in contribution of the fertiliser N-pool after an initial increase is sooner and larger for treatment 1c. The Rayleigh-type model applied to N2 O isotopocules data (δ15 Nbulk -N2 O values) shows poor agreement with the measurements for the original one-pool model for treatment 1c; the two-pool models gives better results when using a third-order polynomial equation. In contrast, in treatment 3c little difference is observed between the two modelling approaches. CONCLUSIONS The importance of N2 O emissions from different N-pools in soil for the interpretation of N2 O isotopocules data was demonstrated using a Rayleigh-type model. Earlier statements concerning exponential increase in native soil nitrate pool activity highlighted in previous studies should be replaced with a polynomial increase with dependency on both N-pool sizes.
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Affiliation(s)
- Antonio Castellano‐Hinojosa
- Department of Microbiology, Faculty of PharmacyUniversity of Granada. Campus Cartuja18071GranadaSpain
- Department of Soil Microbiology and Symbiotic SystemsEstación Experimental del Zaidín18080GranadaSpain
| | - Nadine Loick
- Rothamsted Research, North WykeOkehamptonEX20 2SBUK
| | | | - G. Peter Matthews
- School of Geography, Earth and Environmental SciencesUniversity of PlymouthDavy Building, Drake CircusPlymouthPL4 8AAUK
| | | | - Reinhard Well
- Thünen Institute of Climate‐Smart AgricultureBundesallee 6538116BraunschweigGermany
| | - Roland Bol
- Agrosphere (IBG‐3)Institute of Bio‐ and GeosciencesForschungszentrum Jülich52428JülichGermany
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11
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Wang A, Fang Y, Chen D, Phillips O, Koba K, Zhu W, Zhu J. High nitrogen isotope fractionation of nitrate during denitrification in four forest soils and its implications for denitrification rate estimates. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 633:1078-1088. [PMID: 29758860 DOI: 10.1016/j.scitotenv.2018.03.261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 03/21/2018] [Accepted: 03/22/2018] [Indexed: 06/08/2023]
Abstract
Denitrification is a major process contributing to the removal of nitrogen (N) from ecosystems, but its rate is difficult to quantify. The natural abundance of isotopes can be used to identify the occurrence of denitrification and has recently been used to quantify denitrification rates at the ecosystem level. However, the technique requires an understanding of the isotopic enrichment factor associated with denitrification, which few studies have investigated in forest soils. Here, soils collected from two tropical and two temperate forests in China were incubated under anaerobic or aerobic laboratory conditions for two weeks to determine the N and oxygen (O) isotope enrichment factors during denitrification. We found that at room temperature (20°C), NO3- was reduced at a rate of 0.17 to 0.35μgNg-1h-1, accompanied by the isotope fractionation of N (15ε) and O (18ε) of 31‰ to 65‰ (48.3±2.0‰ on average) and 11‰ to 39‰ (18.9±1.7‰ on average), respectively. The N isotope effects were, unexpectedly, much higher than reported in the literature for heterotrophic denitrification (typically ranging from 5‰ to 30‰) and in other environmental settings (e.g., groundwater, marine sediments and agricultural soils). In addition, the ratios of Δδ18O:Δδ15N ranged from 0.28 to 0.60 (0.38±0.02 on average), which were lower than the canonical ratios of 0.5 to 1 for denitrification reported in other terrestrial and freshwater systems. We suggest that the isotope effects of denitrification for soils may vary greatly among regions and soil types and that gaseous N losses may have been overestimated for terrestrial ecosystems in previous studies in which lower fractionation factors were applied.
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Affiliation(s)
- Ang Wang
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, China; Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China; Qingyuan Forest CERN, Chinese Academy of Sciences, Shenyang 110016, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunting Fang
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, China; Qingyuan Forest CERN, Chinese Academy of Sciences, Shenyang 110016, China.
| | - Dexiang Chen
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China.
| | | | - Keisuke Koba
- Center for Ecological Research, Kyoto University, Shiga 520-2113, Japan
| | - Weixing Zhu
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, China; Department of Biological Sciences, Binghamton University, The State University of New York, Binghamton, NY 13902, USA
| | - Jiaojun Zhu
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, China; Qingyuan Forest CERN, Chinese Academy of Sciences, Shenyang 110016, China
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12
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Modest Gaseous Nitrogen Losses Point to Conservative Nitrogen Cycling in a Lowland Tropical Forest Watershed. Ecosystems 2017. [DOI: 10.1007/s10021-017-0193-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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13
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Duan H, Ye L, Erler D, Ni BJ, Yuan Z. Quantifying nitrous oxide production pathways in wastewater treatment systems using isotope technology - A critical review. WATER RESEARCH 2017; 122:96-113. [PMID: 28595125 DOI: 10.1016/j.watres.2017.05.054] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 05/01/2017] [Accepted: 05/25/2017] [Indexed: 06/07/2023]
Abstract
Nitrous oxide (N2O) is an important greenhouse gas and an ozone-depleting substance which can be emitted from wastewater treatment systems (WWTS) causing significant environmental impacts. Understanding the N2O production pathways and their contribution to total emissions is the key to effective mitigation. Isotope technology is a promising method that has been applied to WWTS for quantifying the N2O production pathways. Within the scope of WWTS, this article reviews the current status of different isotope approaches, including both natural abundance and labelled isotope approaches, to N2O production pathways quantification. It identifies the limitations and potential problems with these approaches, as well as improvement opportunities. We conclude that, while the capabilities of isotope technology have been largely recognized, the quantification of N2O production pathways with isotope technology in WWTS require further improvement, particularly in relation to its accuracy and reliability.
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Affiliation(s)
- Haoran Duan
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia
| | - Liu Ye
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia
| | - Dirk Erler
- Centre for Coastal Biogeochemistry, School of Environmental Science and Engineering, Southern Cross University, Lismore, NSW 2480 Australia
| | - Bing-Jie Ni
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia.
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14
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Ruiz-Navarro A, Barberá GG, Albaladejo J, Querejeta JI. Plant δ 15 N reflects the high landscape-scale heterogeneity of soil fertility and vegetation productivity in a Mediterranean semiarid ecosystem. THE NEW PHYTOLOGIST 2016; 212:1030-1043. [PMID: 27405992 DOI: 10.1111/nph.14091] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 06/05/2016] [Indexed: 06/06/2023]
Abstract
We investigated the magnitude and drivers of spatial variability in soil and plant δ15 N across the landscape in a topographically complex semiarid ecosystem. We hypothesized that large spatial heterogeneity in water availability, soil fertility and vegetation cover would be positively linked to high local-scale variability in δ15 N. We measured foliar δ15 N in three dominant plant species representing contrasting plant functional types (tree, shrub, grass) and mycorrhizal association types (ectomycorrhizal or arbuscular mycorrhizal). This allowed us to investigate whether δ15 N responds to landscape-scale environmental heterogeneity in a consistent way across species. Leaf δ15 N varied greatly within species across the landscape and was strongly spatially correlated among co-occurring individuals of the three species. Plant δ15 N correlated tightly with soil δ15 N and key measures of soil fertility, water availability and vegetation productivity, including soil nitrogen (N), organic carbon (C), plant-available phosphorus (P), water-holding capacity, topographic moisture indices and normalized difference vegetation index. Multiple regression models accounted for 62-83% of within-species variation in δ15 N across the landscape. The tight spatial coupling and interdependence of the water, N and C cycles in drylands may allow the use of leaf δ15 N as an integrative measure of variations in moisture availability, biogeochemical activity, soil fertility and vegetation productivity (or 'site quality') across the landscape.
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Affiliation(s)
- Antonio Ruiz-Navarro
- Department of Soil and Water Conservation, Spanish National Research Council (CEBAS-CSIC), PO Box 164, Campus Universitario de Espinardo, Espinardo, Murcia, E-30100, Spain
| | - Gonzalo G Barberá
- Department of Soil and Water Conservation, Spanish National Research Council (CEBAS-CSIC), PO Box 164, Campus Universitario de Espinardo, Espinardo, Murcia, E-30100, Spain
| | - Juan Albaladejo
- Department of Soil and Water Conservation, Spanish National Research Council (CEBAS-CSIC), PO Box 164, Campus Universitario de Espinardo, Espinardo, Murcia, E-30100, Spain
| | - José I Querejeta
- Department of Soil and Water Conservation, Spanish National Research Council (CEBAS-CSIC), PO Box 164, Campus Universitario de Espinardo, Espinardo, Murcia, E-30100, Spain
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15
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Wu D, Köster JR, Cárdenas LM, Brüggemann N, Lewicka-Szczebak D, Bol R. N2O source partitioning in soils using (15)N site preference values corrected for the N2O reduction effect. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30:620-626. [PMID: 26842583 DOI: 10.1002/rcm.7493] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 12/17/2015] [Accepted: 12/18/2015] [Indexed: 06/05/2023]
Abstract
RATIONALE The aim of this study was to determine the impact of isotope fractionation associated with N2O reduction during soil denitrification on N2O site preference (SP) values and hence quantify the potential bias on SP-based N2O source partitioning. METHODS The N2O SP values (n = 431) were derived from six soil incubation studies in N2-free atmosphere, and determined by isotope ratio mass spectrometry (IRMS). The N2 and N2O concentrations were measured directly by gas chromatography. Net isotope effects (NIE) during N2O reduction to N2 were compensated for using three different approaches: a closed-system model, an open-system model and a dynamic apparent NIE function. The resulting SP values were used for N2O source partitioning based on a two end-member isotopic mass balance. RESULTS The average SP0 value, i.e. the average SP values of N2O prior to N2O reduction, was recalculated with the closed-system model, resulting in -2.6 ‰ (±9.5), while the open-system model and the dynamic apparent NIE model gave average SP0 values of 2.9 ‰ (±6.3) and 1.7 ‰ (±6.3), respectively. The average source contribution of N2O from nitrification/fungal denitrification was 18.7% (±21.0) according to the closed-system model, while the open-system model and the dynamic apparent NIE function resulted in values of 31.0% (±14.0) and 28.3% (±14.0), respectively. CONCLUSIONS Using a closed-system model with a fixed SP isotope effect may significantly overestimate the N2O reduction effect on SP values, especially when N2O reduction rates are high. This is probably due to soil inhomogeneity and can be compensated for by the application of a dynamic apparent NIE function, which takes the variable reduction rates in soil micropores into account.
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Affiliation(s)
- Di Wu
- Institute of Bio- and Geosciences, Agrosphere (IBG-3), Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
| | - Jan Reent Köster
- Department of Environmental Sciences, Norwegian University of Life Sciences, 1432 Ås, Norway
| | | | - Nicolas Brüggemann
- Institute of Bio- and Geosciences, Agrosphere (IBG-3), Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
| | - Dominika Lewicka-Szczebak
- Federal Research Institute for Rural Areas, Forestry and Fisheries, Thünen Institute of Climate-Smart Agriculture, Bundesallee 50, 38116, Braunschweig, Germany
| | - Roland Bol
- Institute of Bio- and Geosciences, Agrosphere (IBG-3), Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
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16
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Hu J, Inglett KS, Clark MW, Inglett PW, Ramesh Reddy K. Nitrous oxide production and consumption by denitrification in a grassland: Effects of grazing and hydrology. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 532:702-710. [PMID: 26119384 DOI: 10.1016/j.scitotenv.2015.06.036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 06/09/2015] [Accepted: 06/10/2015] [Indexed: 06/04/2023]
Abstract
Denitrification is generally recognized as a major mechanism contributing to nitrous oxide (N2O) production, and is the only known biological process for N2O consumption. Understanding factors controlling N2O production and consumption during denitrification will provide insights into N2O emission variability, and potentially predict capacity of soils to serve as sinks or sources of N2O. This study investigated the effects of hydrology and grazing on N2O production and consumption in a grassland based agricultural watershed. A batch incubation study was conducted on soils (0-10 cm) collected along a hydrological gradient representing isolated wetland (Center), transient zone (Edge) and pasture upland (Upland), from both grazed and ungrazed areas. Production and consumption potentials of N2O were quantified on soils under four treatments, including (i) ambient condition, and amended with (ii) NO3(-), (iii) glucose-C, and (iv) NO3(-) +glucose-C. The impacts of grazing on N2O production and consumption were not observed. Soils in hydrologically distinct zones responded differently to N2O production and consumption. Under ambient conditions, both production and consumption rates of Edge soils were higher than those observed for Center and Upland soils. Results of amended incubations suggested NO3(-) was a key factor limiting N2O production and consumption rates in all hydrological zones. Over 5-d incubation with NO3(-) amendment, cumulative production and consumption of N2O for Center soils were 1.6 and 3.3 times higher than Edge soils, and 3.6 and 7.6 times higher than Upland soils, respectively. However, cumulative N2O net production for Edge soils was the highest, with 2 to 3 times higher than Upland and Center soils. Our results suggest that the transient areas between wetland and upland are likely to be "hot spots" of N2O emissions in this ecosystem. Wetlands within agricultural landscapes can potentially function to reduce both NO3(-) leaching and N2O emissions.
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Affiliation(s)
- Jing Hu
- Wetland Biogeochemistry Laboratory, Soil and Water Science Department, University of Florida, Gainesville, FL, USA
| | - Kanika S Inglett
- Wetland Biogeochemistry Laboratory, Soil and Water Science Department, University of Florida, Gainesville, FL, USA
| | - Mark W Clark
- Wetland Biogeochemistry Laboratory, Soil and Water Science Department, University of Florida, Gainesville, FL, USA
| | - Patrick W Inglett
- Wetland Biogeochemistry Laboratory, Soil and Water Science Department, University of Florida, Gainesville, FL, USA
| | - K Ramesh Reddy
- Wetland Biogeochemistry Laboratory, Soil and Water Science Department, University of Florida, Gainesville, FL, USA.
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17
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Vavilin VA, Rytov SV. Nitrate denitrification with nitrite or nitrous oxide as intermediate products: Stoichiometry, kinetics and dynamics of stable isotope signatures. CHEMOSPHERE 2015; 134:417-426. [PMID: 25989520 DOI: 10.1016/j.chemosphere.2015.04.091] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 04/21/2015] [Accepted: 04/28/2015] [Indexed: 06/04/2023]
Abstract
A kinetic analysis of nitrate denitrification by a single or two species of denitrifying bacteria with glucose or ethanol as a carbon source and nitrite or nitrous oxide as intermediate products was performed using experimental data published earlier (Menyailo and Hungate, 2006; Vidal-Gavilan et al., 2013). Modified Monod kinetics was used in the dynamic biological model. The special equations were added to the common dynamic biological model to describe how isotopic fractionation between N species changes. In contrast to the generally assumed first-order kinetics, in this paper, the traditional Rayleigh equation describing stable nitrogen and oxygen isotope fractionation in nitrate was derived from the dynamic isotopic equations for any type of kinetics. In accordance with the model, in Vidal-Gavilan's experiments, the maximum specific rate of nitrate reduction was proved to be less for ethanol compared to glucose. Conversely, the maximum specific rate of nitrite reduction was proved to be much less for glucose compared to ethanol. Thus, the intermediate nitrite concentration was negligible for the ethanol experiment, while it was significant for the glucose experiment. In Menyailo's and Hungate's experiments, the low value of maximum specific rate of nitrous oxide reduction gives high intermediate value of nitrous oxide concentration. The model showed that the dynamics of nitrogen and oxygen isotope signatures are responding to the biological dynamics. Two microbial species instead of single denitrifying bacteria are proved to be more adequate to describe the total process of nitrate denitrification to dinitrogen.
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Affiliation(s)
- V A Vavilin
- Water Problems Institute, Russian Academy of Sciences, 3 Gubkina str., Moscow 119333, Russia.
| | - S V Rytov
- Water Problems Institute, Russian Academy of Sciences, 3 Gubkina str., Moscow 119333, Russia
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18
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Zou Y, Hirono Y, Yanai Y, Hattori S, Toyoda S, Yoshida N. Rainwater, soil water, and soil nitrate effects on oxygen isotope ratios of nitrous oxide produced in a green tea (Camellia sinensis) field in Japan. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2015; 29:891-900. [PMID: 26377018 DOI: 10.1002/rcm.7176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 02/14/2015] [Accepted: 02/20/2015] [Indexed: 06/05/2023]
Abstract
RATIONALE The oxygen exchange fraction between soil H(2)O and N(2)O precursors differs in soils depending on the responsible N(2)O-producing process: nitrification or denitrification. This study investigated the O-exchange between soil H(2)O and N(2)O precursors in a green tea field with high N(2)O emissions. METHODS The rainwater δ(18)O value was measured using cavity ring-down spectrometry (CRDS) and compared with that of soil water collected under the tea plant canopy and between tea plant rows. The intramolecular (15)N site preference in (β) N(α) NO (SP = δ(15)N(α) - δ(15)N(β)) was determined after measuring the δ(15)N(α) and δ(15)N(bulk) values using gas chromatography/isotope ratio mass spectrometry (GC/IRMS), and the δ(18) O values of N(2)O and NO(3)(-) were also measured using GC/IRMS. RESULTS The range of δ(18)O values of rainwater (-11.15‰ to -4.91‰) was wider than that of soil water (-7.94‰ to -5.64‰). The δ(18)O value of soil water at 50 cm depth was not immediately affected by rainwater. At 10 cm and 20 cm depths of soil between tea plant rows, linear regression analyses of δ(18)O-N(2)O (relative to δ(18)O-NO(3)(-)) versus δ(18) O-H(2)O (relative to δ(18)O-NO(3)(-)) yielded slopes of 0.76-0.80 and intercepts of 31-35‰. CONCLUSIONS In soil between tea plant rows, the fraction of O-exchange between H(2)O and N(2)O precursors was approximately 80%. Assuming that denitrification dominated N(2)O production, the net (18)O-isotope effect for denitrification (NO(3)(-) reduction to N(2)O) was approximately 31-35‰, reflecting the upland condition of the tea field.
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Affiliation(s)
- Yun Zou
- Dept. of Environmental Science and Technology, Tokyo Institute of Technology G1-17, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8502, Japan
| | - Yuhei Hirono
- NARO Institute of Vegetable and Tea Science, 2769, Kanaya-Shishidoi, Shimada, Shizuoka, 428-8501, Japan
| | - Yosuke Yanai
- NARO Institute of Vegetable and Tea Science, 3-1-1 Kannondai, Tsukuba, Ibaraki, 305-8666, Japan
| | - Shohei Hattori
- Dept. of Environmental Chemistry and Engineering, Tokyo Institute of Technology G1-17, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8502, Japan
| | - Sakae Toyoda
- Dept. of Environmental Science and Technology, Tokyo Institute of Technology G1-26, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8502, Japan
| | - Naohiro Yoshida
- Dept. of Environmental Chemistry and Engineering, Tokyo Institute of Technology G1-17, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8502, Japan
- Earth-Life Science Institute, Tokyo Institute of Technology, Meguro, Tokyo, 152-8551, Japan
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19
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Bai SH, Xu CY, Xu Z, Blumfield TJ, Zhao H, Wallace H, Reverchon F, Van Zwieten L. Soil and foliar nutrient and nitrogen isotope composition (δ(15)N) at 5 years after poultry litter and green waste biochar amendment in a macadamia orchard. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:3803-3809. [PMID: 25266060 DOI: 10.1007/s11356-014-3649-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 09/22/2014] [Indexed: 06/03/2023]
Abstract
This study aimed to evaluate the improvement in soil fertility and plant nutrient use in a macadamia orchard following biochar application. The main objectives of this study were to assess the effects of poultry litter and green waste biochar applications on nitrogen (N) cycling using N isotope composition (δ(15)N) and nutrient availability in a soil-plant system at a macadamia orchard, 5 years following application. Biochar was applied at 10 t ha(-1) dry weight but concentrated within a 3-m diameter zone when trees were planted in 2007. Soil and leaf samples were collected in 2012, and both soil and foliar N isotope composition (δ(15)N) and nutrient concentrations were assessed. Both soil and foliar δ(15)N increased significantly in the poultry litter biochar plots compared to the green waste biochar and control plots. A significant relationship was observed between soil and plant δ(15)N. There was no influence of either biochars on foliar total N concentrations or soil NH4 (+)-N and NO3 (-)-N, which suggested that biochar application did not pose any restriction for plant N uptake. Plant bioavailable phosphorus (P) was significantly higher in the poultry litter biochar treatment compared to the green waste biochar treatment and control. We hypothesised that the bioavailability of N and P content of poultry litter biochar may play an important role in increasing soil and plant δ(15)N and P concentrations. Biochar application affected soil-plant N cycling and there is potential to use soil and plant δ(15)N to investigate N cycling in a soil-biochar-tree crop system. The poultry litter biochar significantly increased soil fertility compared to the green waste biochar at 5 years following biochar application which makes the poultry litter a better feedstock to produce biochar compared to green waste for the tree crops.
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Affiliation(s)
- Shahla Hosseini Bai
- Environmental Futures Research Institute, School of Natural Sciences, Griffith University, Nathan, Brisbane, Queensland, 4111, Australia,
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20
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Lewicka-Szczebak D, Well R, Bol R, Gregory AS, Matthews GP, Misselbrook T, Whalley WR, Cardenas LM. Isotope fractionation factors controlling isotopocule signatures of soil-emitted N₂O produced by denitrification processes of various rates. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2015; 29:269-282. [PMID: 26411625 DOI: 10.1002/rcm.7102] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 11/14/2014] [Accepted: 11/17/2014] [Indexed: 06/05/2023]
Abstract
RATIONALE This study aimed (i) to determine the isotopic fractionation factors associated with N2O production and reduction during soil denitrification and (ii) to help specify the factors controlling the magnitude of the isotope effects. For the first time the isotope effects of denitrification were determined in an experiment under oxic atmosphere and using a novel approach where N2O production and reduction occurred simultaneously. METHODS Soil incubations were performed under a He/O2 atmosphere and the denitrification product ratio [N2O/(N2 + N2O)] was determined by direct measurement of N2 and N2O fluxes. N2O isotopocules were analyzed by mass spectrometry to determine δ(18)O, δ(15)N and (15)N site preference within the linear N2O molecule (SP). An isotopic model was applied for the simultaneous determination of net isotope effects (η) of both N2O production and reduction, taking into account emissions from two distinct soil pools. RESULTS A clear relationship was observed between (15)N and (18)O isotope effects during N2O production and denitrification rates. For N2O reduction, diverse isotope effects were observed for the two distinct soil pools characterized by different product ratios. For moderate product ratios (from 0.1 to 1.0) the range of isotope effects given by previous studies was confirmed and refined, whereas for very low product ratios (below 0.1) the net isotope effects were much smaller. CONCLUSIONS The fractionation factors associated with denitrification, determined under oxic incubation, are similar to the factors previously determined under anoxic conditions, hence potentially applicable for field studies. However, it was shown that the η(18)O/η(15)N ratios, previously accepted as typical for N2O reduction processes (i.e., higher than 2), are not valid for all conditions.
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Affiliation(s)
- Dominika Lewicka-Szczebak
- Thünen Institute of Climate-Smart Agriculture, Federal Research Institute for Rural Areas, Forestry and Fisheries, Bundesallee 50, D-38116, Braunschweig, Germany
- Institute of Geological Sciences, University of Wrocław, Cybulskiego 30, PL-50-205, Wroclaw, Poland
| | - Reinhard Well
- Thünen Institute of Climate-Smart Agriculture, Federal Research Institute for Rural Areas, Forestry and Fisheries, Bundesallee 50, D-38116, Braunschweig, Germany
| | - Roland Bol
- Forschungszentrum Jülich IBG-3, Wilhelm-Johnen-Straße, 52428, Jülich, Germany
| | | | - G Peter Matthews
- Faculty of Science & Environment, University of Plymouth, Plymouth, PL4 8AA, UK
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21
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Mander U, Well R, Weymann D, Soosaar K, Maddison M, Kanal A, Lõhmus K, Truu J, Augustin J, Tournebize J. Isotopologue ratios of N2O and N2 measurements underpin the importance of denitrification in differently N-loaded riparian alder forests. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:11910-11918. [PMID: 25264900 DOI: 10.1021/es501727h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Known as biogeochemical hotspots in landscapes, riparian buffer zones exhibit considerable potential concerning mitigation of groundwater contaminants such as nitrate, but may in return enhance the risk for indirect N2O emission. Here we aim to assess and to compare two riparian gray alder forests in terms of gaseous N2O and N2 fluxes and dissolved N2O, N2, and NO3(-) in the near-surface groundwater. We further determine for the first time isotopologue ratios of N2O dissolved in the riparian groundwater in order to support our assumption that it mainly originated from denitrification. The study sites, both situated in Estonia, northeastern Europe, receive contrasting N loads from adjacent uphill arable land. Whereas N2O emissions were rather small at both sites, average gaseous N2-to-N2O ratios inferred from closed-chamber measurements and He-O laboratory incubations were almost four times smaller for the heavily loaded site. In contrast, groundwater parameters were less variable among sites and between landscape positions. Campaign-based average (15)N site preferences of N2O (SP) in riparian groundwater ranged between 11 and 44 ‰. Besides the strong prevalence of N2 emission over N2O fluxes and the correlation pattern between isotopologue and water quality data, this comparatively large range highlights the importance of denitrification and N2O reduction in both riparian gray alder stands.
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Affiliation(s)
- Ulo Mander
- Institute of Ecology and Earth Sciences, University of Tartu , 51014 Tartu, Estonia
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22
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Yang H, Gandhi H, Ostrom NE, Hegg EL. Isotopic fractionation by a fungal P450 nitric oxide reductase during the production of N2O. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:10707-10715. [PMID: 25121461 DOI: 10.1021/es501912d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Nitrous oxide (N2O) is a potent greenhouse gas with a 100-year global warming potential approximately 300 times that of CO2. Because microbes account for over 75% of the N2O released in the U.S., understanding the biochemical processes by which N2O is produced is critical to our efforts to mitigate climate change. In the current study, we used gas chromatography-isotope ratio mass spectrometry (GC-IRMS) to measure the δ(15)N, δ(18)O, δ(15)N(α), and δ(15)N(β) of N2O generated by purified fungal nitric oxide reductase (P450nor) from Histoplasma capsulatum. The isotope values were used to calculate site preference (SP) values (difference in δ(15)N between the central (α) and terminal (β) N atoms in N2O), enrichment factors (ε), and kinetic isotope effects (KIEs). Both oxygen and N(α) displayed normal isotope effects during enzymatic NO reduction with ε values of -25.7‰ (KIE = 1.0264) and -12.6‰ (KIE = 1.0127), respectively. However, bulk nitrogen (average δ(15)N of N(α) and N(β)) and N(β) exhibited inverse isotope effects with ε values of 14.0‰ (KIE = 0.9862) and 36.1‰ (KIE = 0.9651), respectively. The observed inverse isotope effect in δ(15)N(β) is consistent with reversible binding of the first NO in the P450nor reaction mechanism. In contrast to the constant SP observed during NO reduction in microbial cultures, the site preference measured for purified H. capsulatum P450nor was not constant, increasing from ∼ 15‰ to ∼ 29‰ during the course of the reaction. This indicates that SP for microbial cultures can vary depending on the growth conditions, which may complicate source tracing during microbial denitrification.
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Affiliation(s)
- Hui Yang
- Department of Biochemistry & Molecular Biology, Michigan State University , East Lansing, Michigan 48824, United States
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Köster JR, Well R, Dittert K, Giesemann A, Lewicka-Szczebak D, Mühling KH, Herrmann A, Lammel J, Senbayram M. Soil denitrification potential and its influence on N2O reduction and N2O isotopomer ratios. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2013; 27:2363-2373. [PMID: 24097392 DOI: 10.1002/rcm.6699] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 07/27/2013] [Accepted: 07/29/2013] [Indexed: 06/02/2023]
Abstract
RATIONALE N2O isotopomer ratios may provide a useful tool for studying N2O source processes in soils and may also help estimating N2O reduction to N2. However, remaining uncertainties about different processes and their characteristic isotope effects still hamper its application. We conducted two laboratory incubation experiments (i) to compare the denitrification potential and N2O/(N2O+N2) product ratio of denitrification of various soil types from Northern Germany, and (ii) to investigate the effect of N2O reduction on the intramolecular (15)N distribution of emitted N2O. METHODS Three contrasting soils (clay, loamy, and sandy soil) were amended with nitrate solution and incubated under N2 -free He atmosphere in a fully automated incubation system over 9 or 28 days in two experiments. N2O, N2, and CO2 release was quantified by online gas chromatography. In addition, the N2O isotopomer ratios were determined by isotope-ratio mass spectrometry (IRMS) and the net enrichment factors of the (15)N site preference (SP) of the N2O-to-N2 reduction step (η(SP)) were estimated using a Rayleigh model. RESULTS The total denitrification rate was highest in clay soil and lowest in sandy soil. Surprisingly, the N2O/(N2O+N2) product ratio in clay and loam soil was identical; however, it was significantly lower in sandy soil. The IRMS measurements revealed highest N2O SP values in clay soil and lowest SP values in sandy soil. The η(SP) values of N2O reduction were between -8.2 and -6.1‰, and a significant relationship between δ(18)O and SP values was found. CONCLUSIONS Both experiments showed that the N2O/(N2O+N2) product ratio of denitrification is not solely controlled by the available carbon content of the soil or by the denitrification rate. Differences in N2O SP values could not be explained by variations in N2O reduction between soils, but rather originate from other processes involved in denitrification. The linear δ(18)O vs SP relationship may be indicative for N2O reduction; however, it deviates significantly from the findings of previous studies.
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Affiliation(s)
- Jan Reent Köster
- Institute of Plant Nutrition and Soil Science, Kiel University, Hermann-Rodewald-Str. 2, D-24118, Kiel, Germany
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Phillips R, Griffith DWT, Dijkstra F, Lugg G, Lawrie R, Macdonald B. Tracking short-term effects of nitrogen-15 addition on nitrous oxide fluxes using fourier-transform infrared spectroscopy. JOURNAL OF ENVIRONMENTAL QUALITY 2013; 42:1327-1340. [PMID: 24216411 DOI: 10.2134/jeq2013.02.0067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Synthetic fertilizer N additions to soils have significantly increased atmospheric NO concentrations, and advanced methods are needed to track the amount of applied N that is transformed to NO in the field. We have developed a method for continuous measurement of NO isotopologues (NNO, NNO, NNO, and NNO) following 0.4 and 0.8 g N m of N-labeled substrate as KNO or urea [CO(NH)] using Fourier-transform infrared (FTIR) spectroscopy. We evaluated this method using two 4-wk experimental trials on a coastal floodplain site near Nowra, New South Wales, Australia, which is managed for silage production. We deployed an automated five-chamber system connected to a portable FTIR spectrometer with multipass cell to measure NO isotopologue fluxes. Emissions of all isotopologues were evident immediately following N addition. All isotopologues responded positively to rainfall events, but only for 7 to 10 d following N addition. Cumulative N-NO fluxes (sum of the three N isotopologues) per chamber for the 14 d following N addition ranged from 1.5 to 10.3 mg N m. Approximately 1% (range 0.7-1.9%) of the total amount of N applied was emitted as NO. Repeatability (1σ) for all isotopologue measurements was better than 0.5 nmol mol for 1-min average concentration measurements, and minimum detectable fluxes for each isotopologue were <0.1 ng N m s. The results indicate that the portable FTIR spectroscopic technique can effectively trace transfer of N to the atmosphere as NO after N addition, allowing powerful quantification of NO emissions under field conditions.
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Potter KE, Ono S, Prinn RG. Fully automated, high-precision instrumentation for the isotopic analysis of tropospheric N2O using continuous flow isotope ratio mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2013; 27:1723-1738. [PMID: 23821566 DOI: 10.1002/rcm.6623] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 05/06/2013] [Accepted: 05/07/2013] [Indexed: 06/02/2023]
Abstract
RATIONALE Measurements of the isotopic composition of nitrous oxide in the troposphere have the potential to bring new information about the uncertain N2O budget, which mole fraction data alone have not been able to resolve. Characterizing the expected subtle variations in tropospheric N2O isotopic composition demands high-precision and high-frequency measurements. To enable useful observations of N2O isotopic composition in tropospheric air to reduce N2O source and sink uncertainty, it was necessary to develop a high-precision measurement system with fully automated capabilities for autonomous deployment at remote research stations. METHODS A fully automated pre-concentration system for high-precision measurements of N2O isotopic composition (δ(15)N(β) , δ(15)N(α), δ(18)O) in tropospheric air has been developed which combines a custom liquid-cryogen-free cryo-trapping system and gas chromatograph interfaced to a continuous flow isotope ratio mass spectrometry (IRMS) system. A quadrupole mass spectrometer was coupled in parallel to the IRMS system during development to evaluate peak interference. Multi-port inlet and fully-automated capabilities allow streamlined analyses between in situ air inlet, air standards, flask air sample, or other gas source in exactly replicated analysis sequences. RESULTS The system has the highest precision to date for (15)N site-specific composition results (δ(15) N(α) ±0.11‰, δ(15)N(β) ±0.14‰ (1σ)), attributed mostly to uniformity of analytical cycles and particular attention to fluorocarbon interference noted for (15)N site-specific measurements by IRMS. Air measurements demonstrated the fully automated capacity and performance. CONCLUSIONS The system makes substantial headway in measurement precision, possibly defining the limits of IRMS measurement capabilities in low concentration N2O air samples, with fully automated capabilities to enable high-frequency in situ measurements.
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Affiliation(s)
- Katherine E Potter
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.
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Kato T, Toyoda S, Yoshida N, Tang Y, Wada E. Isotopomer and isotopologue signatures of N2O produced in alpine ecosystems on the Qinghai-Tibetan Plateau. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2013; 27:1517-1526. [PMID: 23722686 DOI: 10.1002/rcm.6595] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 03/31/2013] [Accepted: 04/01/2013] [Indexed: 06/02/2023]
Abstract
RATIONALE Static-chamber flux measurements have suggested that one of the world's largest grasslands, the Qinghai-Tibetan Plateau (QTP), is a potential source of nitrous oxide (N2O), a major greenhouse gas. However, production and consumption pathways of N2O have not been identified by in situ field measurements. METHODS Ratios of N2O isotopomers ((14)N(15)N(16)O and (15)N(14)N(16)O) and an isotopologue ((14)N(14)N(18)O) with respect to (14)N(14)N(16)O in the atmosphere, static chambers, and soils were measured by gas chromatography and mass spectrometry in the summer of 2005 and the following winter of 2006 at three typical alpine ecosystems: alpine meadow, alpine shrub, and alpine wetland, on the QTP, China. RESULTS Site preference (SP) values of soil-emitted N2 O were estimated as 33.7‰ and 30.1‰ for alpine meadow and shrub, respectively, suggesting larger contributions by fungal denitrification, than by bacterial denitrification and nitrifier-denitrification, to N2 O production. Statistical analysis of the relationship between SP and δ(15)N(bulk) values indicated that in alpine meadow, shrub, and wetland sites fungal denitrification contributed 40.7%, 40.0%, and 23.2% to gross N2O production and the produced N2O was reduced by 87.6%, 82.9%, and 92.7%, respectively. CONCLUSIONS The combined measurements of N2O concentration, flux, and isotopomeric signatures provide a robust estimation of N2O circulation dynamics in alpine ecosystems on the QTP, which would contribute to the development of ecosystem nitrogen cycle model.
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Affiliation(s)
- Tomomichi Kato
- Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokohama, Kanagawa, Japan.
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Butterbach-Bahl K, Baggs EM, Dannenmann M, Kiese R, Zechmeister-Boltenstern S. Nitrous oxide emissions from soils: how well do we understand the processes and their controls? Philos Trans R Soc Lond B Biol Sci 2013; 368:20130122. [PMID: 23713120 PMCID: PMC3682742 DOI: 10.1098/rstb.2013.0122] [Citation(s) in RCA: 647] [Impact Index Per Article: 58.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Although it is well established that soils are the dominating source for atmospheric nitrous oxide (N2O), we are still struggling to fully understand the complexity of the underlying microbial production and consumption processes and the links to biotic (e.g. inter- and intraspecies competition, food webs, plant–microbe interaction) and abiotic (e.g. soil climate, physics and chemistry) factors. Recent work shows that a better understanding of the composition and diversity of the microbial community across a variety of soils in different climates and under different land use, as well as plant–microbe interactions in the rhizosphere, may provide a key to better understand the variability of N2O fluxes at the soil–atmosphere interface. Moreover, recent insights into the regulation of the reduction of N2O to dinitrogen (N2) have increased our understanding of N2O exchange. This improved process understanding, building on the increased use of isotope tracing techniques and metagenomics, needs to go along with improvements in measurement techniques for N2O (and N2) emission in order to obtain robust field and laboratory datasets for different ecosystem types. Advances in both fields are currently used to improve process descriptions in biogeochemical models, which may eventually be used not only to test our current process understanding from the microsite to the field level, but also used as tools for up-scaling emissions to landscapes and regions and to explore feedbacks of soil N2O emissions to changes in environmental conditions, land management and land use.
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Affiliation(s)
- Klaus Butterbach-Bahl
- Karlsruhe Institute of Technology, Institute for Meteorology and Climate Research, Atmospheric Environmental Research (IMK-IFU), Kreuzeckbahnstrasse 19, Garmisch-Partenkirchen 82467, Germany.
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Using stable isotopes to follow excreta N dynamics and N2O emissions in animal production systems. Animal 2013; 7 Suppl 2:418-26. [DOI: 10.1017/s1751731113000773] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Schreiber F, Wunderlin P, Udert KM, Wells GF. Nitric oxide and nitrous oxide turnover in natural and engineered microbial communities: biological pathways, chemical reactions, and novel technologies. Front Microbiol 2012; 3:372. [PMID: 23109930 PMCID: PMC3478589 DOI: 10.3389/fmicb.2012.00372] [Citation(s) in RCA: 139] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 09/28/2012] [Indexed: 12/20/2022] Open
Abstract
Nitrous oxide (N(2)O) is an environmentally important atmospheric trace gas because it is an effective greenhouse gas and it leads to ozone depletion through photo-chemical nitric oxide (NO) production in the stratosphere. Mitigating its steady increase in atmospheric concentration requires an understanding of the mechanisms that lead to its formation in natural and engineered microbial communities. N(2)O is formed biologically from the oxidation of hydroxylamine (NH(2)OH) or the reduction of nitrite (NO(-) (2)) to NO and further to N(2)O. Our review of the biological pathways for N(2)O production shows that apparently all organisms and pathways known to be involved in the catabolic branch of microbial N-cycle have the potential to catalyze the reduction of NO(-) (2) to NO and the further reduction of NO to N(2)O, while N(2)O formation from NH(2)OH is only performed by ammonia oxidizing bacteria (AOB). In addition to biological pathways, we review important chemical reactions that can lead to NO and N(2)O formation due to the reactivity of NO(-) (2), NH(2)OH, and nitroxyl (HNO). Moreover, biological N(2)O formation is highly dynamic in response to N-imbalance imposed on a system. Thus, understanding NO formation and capturing the dynamics of NO and N(2)O build-up are key to understand mechanisms of N(2)O release. Here, we discuss novel technologies that allow experiments on NO and N(2)O formation at high temporal resolution, namely NO and N(2)O microelectrodes and the dynamic analysis of the isotopic signature of N(2)O with quantum cascade laser absorption spectroscopy (QCLAS). In addition, we introduce other techniques that use the isotopic composition of N(2)O to distinguish production pathways and findings that were made with emerging molecular techniques in complex environments. Finally, we discuss how a combination of the presented tools might help to address important open questions on pathways and controls of nitrogen flow through complex microbial communities that eventually lead to N(2)O build-up.
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Affiliation(s)
- Frank Schreiber
- Department of Environmental Microbiology, Eawag - Swiss Federal Institute of Aquatic Science and Technology Dübendorf, Switzerland ; Department of Environmental Systems Sciences, Eidgenössische Technische Hochschule Zurich, Switzerland
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Tang FHM, Maggi F. The effect of (15)N to (14)N ratio on nitrification, denitrification and dissimilatory nitrate reduction. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2012; 26:430-442. [PMID: 22279019 DOI: 10.1002/rcm.6119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
RATIONALE Earlier experiments demonstrated that isotopic effects during nitrification, denitrification and dissimilatory nitrate reduction can be affected by high (15) N contents. These findings call into question whether the reaction parameters (rate constants and Michaelis-Menten concentrations) are function of δ(15) N values, and if these can also lead to significant effects on the bulk reaction rate. METHODS Five experiments at initial δ(15) N-NO(3) (-) values ranging from 0‰ to 1700‰ were carried out in a recent study using elemental analyser, gas chromatography, and mass spectrometry techniques coupled at various levels. These data were combined here with kinetic equations of isotopologue speciation and fractionation. Our approach specifically addressed the combinatorial nature of reactions involving labeled atoms and explicitly described substrate competition and time-dependent isotopic effects. RESULTS With the method presented here, we determined with relatively high accuracy that the reaction rate constants increased linearly up to 270% and the Michaelis-Menten concentrations decreased linearly by about 30% over the tested δ(15) N-NO(3) (-) values. Because the parameters were found to depend on the (15) N enrichment level, we could determine that increasing δ(15) N-NO(3) (-) values caused a decrease in bulk nitrification, denitrification and dissimilatory nitrate reduction rates by 50% to 60%. CONCLUSIONS We addressed a method that allowed us to quantify the effect of substrate isotopic enrichment on the reaction kinetics. Our results enable us to reject the assumption of constant reaction parameters. The implications of δ-dependent (variable) reaction parameters extend beyond the study-case analysed here to all instances in which high and variable isotopic enrichments occur.
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Affiliation(s)
- Fiona H M Tang
- School of Civil Engineering, The University of Sydney, 2006, Sydney, NSW, Australia
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The Isotopomers of Nitrous Oxide: Analytical Considerations and Application to Resolution of Microbial Production Pathways. ADVANCES IN ISOTOPE GEOCHEMISTRY 2012. [DOI: 10.1007/978-3-642-10637-8_23] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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Townsend-Small A, Pataki DE, Tseng LY, Tsai CY, Rosso D. Nitrous oxide emissions from wastewater treatment and water reclamation plants in southern California. JOURNAL OF ENVIRONMENTAL QUALITY 2011; 40:1542-50. [PMID: 21869516 DOI: 10.2134/jeq2011.0059] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Nitrous oxide (N₂O) is a long-lived and potent greenhouse gas produced during microbial nitrification and denitrification. In developed countries, centralized water reclamation plants often use these processes for N removal before effluent is used for irrigation or discharged to surface water, thus making this treatment a potentially large source of N₂O in urban areas. In the arid but densely populated southwestern United States, water reclamation for irrigation is an important alternative to long-distance water importation. We measured N₂O concentrations and fluxes from several wastewater treatment processes in urban southern California. We found that N removal during water reclamation may lead to in situ N₂O emission rates that are three or more times greater than traditional treatment processes (C oxidation only). In the water reclamation plants tested, N₂O production was a greater percentage of total N removed (1.2%) than traditional treatment processes (C oxidation only) (0.4%). We also measured stable isotope ratios (δN and δO) of emitted N₂O and found distinct δN signatures of N₂O from denitrification (0.0 ± 4.0 ‰) and nitrification reactors (-24.5 ± 2.2 ‰), respectively. These isotope data confirm that both nitrification and denitrification contribute to N₂O emissions within the same treatment plant. Our estimates indicate that N₂O emissions from biological N removal for water reclamation may be several orders of magnitude greater than N₂O emissions from agricultural activities in highly urbanized southern California. Our results suggest that wastewater treatment that includes biological nitrogen removal can significantly increase urban N₂O emissions.
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Townsend-Small A, Pataki DE, Czimczik CI, Tyler SC. Nitrous oxide emissions and isotopic composition in urban and agricultural systems in southern California. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jg001494] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Croteau P, Atlas EL, Schauffler SM, Blake DR, Diskin GS, Boering KA. Effect of local and regional sources on the isotopic composition of nitrous oxide in the tropical free troposphere and tropopause layer. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd013117] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Maggi F, Riley WJ. Transient competitive complexation in biological kinetic isotope fractionation explains nonsteady isotopic effects: Theory and application to denitrification in soils. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008jg000878] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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36
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Well R, Flessa H. Isotopologue signatures of N2O produced by denitrification in soils. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008jg000804] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- R. Well
- Büsgen Institute; Universität Göttingen; Göttingen Germany
| | - H. Flessa
- Institute of Agricultural Climate Research; Johann Heinrich von Thünen-Institut; Braunschweig Germany
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Xiong ZQ, Khalil MAK, Xing G, Shearer MJ, Butenhoff C. Isotopic signatures and concentration profiles of nitrous oxide in a rice-based ecosystem during the drained crop-growing season. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008jg000827] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Z. Q. Xiong
- College of Resources and Environmental Sciences; Nanjing Agricultural University; Nanjing China
- Department of Physics; Portland State University; Portland Oregon USA
| | - M. A. K. Khalil
- Department of Physics; Portland State University; Portland Oregon USA
| | - G. Xing
- State Key Laboratory of Soil and Sustainable Agriculture; Institute of Soil Science, Chinese Academy of Sciences; Nanjing China
| | - M. J. Shearer
- Department of Physics; Portland State University; Portland Oregon USA
| | - C. Butenhoff
- Department of Physics; Portland State University; Portland Oregon USA
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Toyoda S, Iwai H, Koba K, Yoshida N. Isotopomeric analysis of N2O dissolved in a river in the Tokyo metropolitan area. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2009; 23:809-821. [PMID: 19222057 DOI: 10.1002/rcm.3945] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
River water has been suggested as a potential source of nitrous oxide (N2O), which is a greenhouse gas that is accumulating rapidly in the troposphere and which is a precursor to stratospheric NOx that depletes ozone. Previous studies on freshwater N2O sources have specifically examined estuaries where sedimentary N2O production might be important and a few points near anthropogenic nitrogen sources such as agricultural or municipal wastewater areas. Here we present the first observation of a temporal and horizontal distribution of N2O and its isotopomers between the midstream and estuary of an urban river. Surface water was supersaturated (100-6800%) with N2O at all stations during the study period. The average or maximum saturation value was greater than described in most previous reports. High N2O concentrations were observed near sewage plants and the unique signature of isotopomer ratios implied direct N2O addition from the plants. The isotopomer ratios also suggested N2O production/consumption at the sediment-water interface. Fluxes and isotopomer ratios of N2O, from the river to the atmosphere, estimated from our observations, indicated that the urban river is indeed a source of atmospheric N2O and that its production could be distinguished from other natural or anthropogenic sources using isotopomer ratios.
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Affiliation(s)
- Sakae Toyoda
- Department of Environmental Chemistry and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan.
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Sutka RL, Adams GC, Ostrom NE, Ostrom PH. Isotopologue fractionation during N(2)O production by fungal denitrification. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2008; 22:3989-3996. [PMID: 19016253 DOI: 10.1002/rcm.3820] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Identifying the importance of fungi to nitrous oxide (N2O) production requires a non-intrusive method for differentiating between fungal and bacterial N2O production such as natural abundance stable isotopes. We compare the isotopologue composition of N2O produced during nitrite reduction by the fungal denitrifiers Fusarium oxysporum and Cylindrocarpon tonkinense with published data for N2O production during bacterial nitrification and denitrification. The fractionation factors for bulk nitrogen isotope values for fungal denitrification were in the range -74.7 to -6.6 per thousand. There was an inverse relationship between the absolute value of the fractionation factors and the reaction rate constant. We interpret this in terms of variation in the relative importance of the rate constants for diffusion and enzymatic reduction in controlling the net isotope effect for N2O production during fungal denitrification. Over the course of nitrite reduction, the delta(18)O values for N2O remained constant and did not exhibit a relationship with the concentration characteristic of an isotope effect. This probably reflects isotopic exchange with water. Similar to the delta(18)O data, the site preference (SP; the difference in delta(15)N between the central and outer N atoms in N2O) was unrelated to concentration during nitrite reduction and, therefore, has the potential to act as a conservative tracer of production from fungal denitrification. The SP values of N2O produced by F. oxysporum and C. tonkinense were 37.1 +/- 2.5 per thousand and 36.9 +/- 2.8 per thousand, respectively. These SP values are similar to those obtained in pure culture studies of bacterial nitrification but quite distinct from SP values for bacterial denitrification. The large magnitude of the bulk nitrogen isotope fractionation and the delta(18)O values associated with fungal denitrification are distinct from bacterial production pathways; thus multiple isotopologue data holds much promise for resolving bacterial and fungal production. Our work further provides insight into the role that fungal and bacterial nitric oxide reductases have in determining site preference during N2O production.
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Affiliation(s)
- Robin L Sutka
- Elementar Inc., Isoprime House, Stanley Green Trading Estate, Earl Road, Cheadle Hulme, Cheadle, UK
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Nardoto GB, Ometto JPHB, Ehleringer JR, Higuchi N, Bustamante MMDC, Martinelli LA. Understanding the Influences of Spatial Patterns on N Availability Within the Brazilian Amazon Forest. Ecosystems 2008. [DOI: 10.1007/s10021-008-9189-1] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Well R, Flessa H. Isotope fractionation factors of N2O diffusion. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2008; 22:2621-2628. [PMID: 18666201 DOI: 10.1002/rcm.3656] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Isotopic signatures of N2O are increasingly used to constrain the total global flux and the relative contribution of nitrification and denitrification to N2O emissions. Interpretation of isotopic signatures of soil-emitted N2O can be complicated by the isotopic effects of gas diffusion. The aim of our study was to measure the isotopic fractionation factors of diffusion for the isotopologues of N2O and to estimate the potential effect of diffusive fractionation during N2O fluxes from soils using simple simulations. Diffusion experiments were conducted to monitor isotopic signatures of N2O in reservoirs that lost N2O by defined diffusive fluxes. Two different mathematical approaches were used to derive diffusive isotope fractionation factors for 18O (epsilon18O), average 15N (epsilonbulk) and 15N of the central (alpha(-)) and peripheral (beta(-)) position within the linear N2O molecule (epsilon15Nalpha, epsilon15Nbeta). The measured epsilon18O was -7.79 +/- 0.27 per thousand and thus higher than the theoretical value of -8.7 per thousand. Conversely, the measured epsilonbulk (-5.23 +/- 0.27 per thousand) was lower than the theoretical value (-4.4 per thousand). The measured site-specific 15N fractionation factors were not equal, giving a difference between epsilon15Nalpha and epsilon15Nbeta (epsilonSP) of 1.55 +/- 0.28 per thousand. Diffusive fluxes of the N2O isotopologues from the soil pore space to the atmosphere were simulated, showing that isotopic signatures of N2O source pools and emitted N2O can be substantially different during periods of non-steady state fluxes. Our results show that diffusive isotope fractionation should be taken into account when interpreting natural abundance isotopic signatures of N2O fluxes from soils.
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Affiliation(s)
- Reinhard Well
- Soil Science of Temperate and Boreal Ecosystems, Buesgeninstitute, University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany.
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Baggs EM. A review of stable isotope techniques for N2O source partitioning in soils: recent progress, remaining challenges and future considerations. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2008; 22:1664-1672. [PMID: 18435506 DOI: 10.1002/rcm.3456] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Nitrous oxide is produced in soil during several processes, which may occur simultaneously within different micro-sites of the same soil. Stable isotope techniques have a crucial role to play in the attribution of N(2)O emissions to different microbial processes, through estimation (natural abundance, site preference) or quantification (enrichment) of processes based on the (15)N and (18)O signatures of N(2)O determined by isotope ratio mass spectrometry. These approaches have the potential to become even more powerful when linked with recent developments in secondary isotope mass spectrometry, with microbial ecology, and with modelling approaches, enabling sources of N(2)O to be considered at a wide range of scales and related to the underlying microbiology. Such source partitioning of N(2)O is inherently challenging, but is vital to close the N(2)O budget and to better understand controls on the different processes, with a view to developing appropriate management practices for mitigation of N(2)O. In this respect, it is essential that as many of the contributing processes as possible are considered in any study aimed at source attribution, as mitigation strategies for one process may not be appropriate for another. To aid such an approach, here the current state of the art is critically examined, remaining challenges are highlighted, and recommendations are made for future direction.
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Affiliation(s)
- E M Baggs
- School of Biological Sciences (Plant & Soil Science), University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen AB24 3UU, UK.
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Kool DM, Wrage N, Oenema O, Dolfing J, Van Groenigen JW. Oxygen exchange between (de)nitrification intermediates and H2O and its implications for source determination of NO3- and N2O: a review. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:3569-3578. [PMID: 17935120 DOI: 10.1002/rcm.3249] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Stable isotope analysis of oxygen (O) is increasingly used to determine the origin of nitrate (NO(3)-) and nitrous oxide (N(2)O) in the environment. The assumption underlying these studies is that the (18)O signature of NO(3)- and N(2)O provides information on the different O sources (O(2) and H(2)O) during the production of these compounds by various biochemical pathways. However, exchange of O atoms between H(2)O and intermediates of the (de)nitrification pathways may change the isotopic signal and thereby bias its interpretation for source determination. Chemical exchange of O between H(2)O and various nitrogenous oxides has been reported, but the probability and extent of its occurrence in terrestrial ecosystems remain unclear. Biochemical O exchange between H(2)O and nitrogenous oxides, NO(2)- in particular, has been reported for monocultures of many nitrifiers and denitrifiers that are abundant in nature, with exchange rates of up to 100%. Therefore, biochemical O exchange is likely to be important in most soil ecosystems, and should be taken into account in source determination studies. Failing to do so might lead to (i) an overestimation of nitrification as NO(3)- source, and (ii) an overestimation of nitrifier denitrification and nitrification-coupled denitrification as N(2)O production pathways. A method to quantify the rate and controls of biochemical O exchange in ecosystems is needed, and we argue this can only be done reliably with artificially enriched (18)O compounds. We conclude that in N source determination studies, the O isotopic signature of especially N(2)O should only be used with extreme caution.
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Affiliation(s)
- D M Kool
- Alterra, Wageningen University and Research Centre, Wageningen, The Netherlands.
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