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Huang J, Liu R, Wang Q, Gao X, Han Z, Gao J, Gao H, Zhang S, Wang J, Zhang L, Xia X. Climate factors affect N 2O emissions by influencing the migration and transformation of nonpoint source nitrogen in an agricultural watershed. WATER RESEARCH 2022; 223:119028. [PMID: 36063704 DOI: 10.1016/j.watres.2022.119028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 08/11/2022] [Accepted: 08/26/2022] [Indexed: 06/15/2023]
Abstract
Precipitation can affect the residence time of nitrogen compounds, and temperature can influence nitrogen transformation in soil. Therefore, we hypothesized that climate factors can affect the emissions of N2O, an important greenhouse gas produced via nitrogen transformation, by influencing the migration and transformation of nonpoint source nitrogen in soil. To test this hypothesis and quantify the effect of climate factors on N2O emissions, the SWAT model and the modified SWAT-N2O coupler were used to study the effect of climate factors on the migration and transformation of nonpoint source nitrogen and N2O emissions in an agricultural watershed from 2009 to 2018. Temperature affected N2O emissions more significant than precipitation, and N2O emissions increased with temperature and reached a plateau when the average monthly temperature was 23.0 °C. The N2O emissions first increased rapidly with precipitation due to the increase in moisture. However, when the average monthly precipitation reached 78.8 mm, the N2O emissions began to decrease because the residence time of nitrogen compounds in soil were reduced due to fast removal via runoff, which inhibits N2O emissions. Under the context of climate change with three scenarios (RCP2.6, RCP4.5, RCP8.5), temperature would increase gradually while precipitation would not change significantly from 2021 to 2080, as a result, the changes would increase N2O emissions by 6.7%, 32.3%, and 70.7%, respectively. This study quantifies the feedback of N2O emissions to climate change in croplands, providing a scientific basis for climate change mitigation and agricultural management.
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Affiliation(s)
- Jing Huang
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Ruimin Liu
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
| | - Qingrui Wang
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xiang Gao
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhenyu Han
- National Climate Center, China Meteorological Administration, Beijing 100081, China
| | - Jiameng Gao
- College of Information Sciences and Technology, Gansu Agricultural University, Lanzhou 730070, China
| | - Hui Gao
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Sibo Zhang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Junfeng Wang
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Ling Zhang
- Yellow River Institute of Hydraulic Research, Zhengzhou 450003, China
| | - Xinghui Xia
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
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2
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Obrist DS, Fitzpatrick OT, Brown NEM, Hanly PJ, Nijland W, Reshitnyk LY, Wickham SB, Darimont CT, Reynolds JD, Starzomski BM. Scale-dependent effects of marine subsidies on the island biogeographic patterns of plants. Ecol Evol 2022; 12:e9270. [PMID: 36177118 PMCID: PMC9461347 DOI: 10.1002/ece3.9270] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 08/14/2022] [Accepted: 08/15/2022] [Indexed: 11/08/2022] Open
Abstract
Although species richness can be determined by different mechanisms at different spatial scales, the role of scale in the effects of marine inputs on island biogeography has not been studied explicitly. Here, we evaluated the potential influence of island characteristics and marine inputs (seaweed wrack biomass and marine‐derived nitrogen in the soil) on plant species richness at both a local (plot) and regional (island) scale on 92 islands in British Columbia, Canada. We found that the effects of subsidies on species richness depend strongly on spatial scale. Despite detecting no effects of marine subsidies at the island scale, we found that as plot level subsidies increased, species richness decreased; plots with more marine‐derived nitrogen in the soil hosted fewer plant species. We found no effect of seaweed wrack at either scale. To identify potential mechanisms underlying the decrease in diversity, we fit a spatially explicit joint species distribution model to evaluate species level responses to marine subsidies and effects of biotic interactions among species. We found mixed evidence for competition for both light and nutrients, and cannot rule out an alternative mechanism; the observed decrease in species richness may be due to disturbances associated with animal‐mediated nutrient deposits, particularly those from North American river otters (Lontra canadensis). By evaluating the scale‐dependent effects of marine subsidies on island biogeographic patterns of plants and revealing likely mechanisms that act on community composition, we provide novel insights on the scale dependence of a fundamental ecological theory, and on the rarely examined links between marine and terrestrial ecosystems often bridged by animal vectors.
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Affiliation(s)
- Debora S Obrist
- Earth to Ocean Research Group, Department of Biological Sciences Simon Fraser University Burnaby British Columbia Canada.,Hakai Institute Heriot Bay British Columbia Canada
| | - Owen T Fitzpatrick
- Hakai Institute Heriot Bay British Columbia Canada.,School of Environmental Studies University of Victoria Victoria British Columbia Canada
| | - Norah E M Brown
- Hakai Institute Heriot Bay British Columbia Canada.,School of Environmental Studies University of Victoria Victoria British Columbia Canada
| | - Patrick J Hanly
- Earth to Ocean Research Group, Department of Biological Sciences Simon Fraser University Burnaby British Columbia Canada.,Hakai Institute Heriot Bay British Columbia Canada.,Department of Fisheries and Wildlife Michigan State University East Lansing Michigan USA
| | - Wiebe Nijland
- Hakai Institute Heriot Bay British Columbia Canada.,School of Environmental Studies University of Victoria Victoria British Columbia Canada.,Department of Physical Geography Utrecht University Utrecht The Netherlands
| | | | - Sara B Wickham
- Hakai Institute Heriot Bay British Columbia Canada.,School of Environmental Studies University of Victoria Victoria British Columbia Canada
| | - Chris T Darimont
- Hakai Institute Heriot Bay British Columbia Canada.,Department of Geography University of Victoria Victoria British Columbia Canada.,Raincoast Conservation Foundation Sidney British Columbia Canada
| | - John D Reynolds
- Earth to Ocean Research Group, Department of Biological Sciences Simon Fraser University Burnaby British Columbia Canada.,Hakai Institute Heriot Bay British Columbia Canada
| | - Brian M Starzomski
- Hakai Institute Heriot Bay British Columbia Canada.,School of Environmental Studies University of Victoria Victoria British Columbia Canada
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3
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Bhattacharyya SS, Leite FFGD, France CL, Adekoya AO, Ros GH, de Vries W, Melchor-Martínez EM, Iqbal HMN, Parra-Saldívar R. Soil carbon sequestration, greenhouse gas emissions, and water pollution under different tillage practices. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 826:154161. [PMID: 35231506 DOI: 10.1016/j.scitotenv.2022.154161] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 02/20/2022] [Accepted: 02/23/2022] [Indexed: 02/08/2023]
Abstract
Tillage is a common agricultural practice and a critical component of agricultural systems that is frequently employed worldwide in croplands to reduce climatic and soil restrictions while also sustaining various ecosystem services. Tillage can affect a variety of soil-mediated processes, e.g., soil carbon sequestration (SCS) or depletion, greenhouse gas (GHG) (CO2, CH4, and N2O) emission, and water pollution. Several tillage practices are in vogue globally, and they exhibit varied impacts on these processes. Hence, there is a dire need to synthesize, collate and comprehensively present these interlinked phenomena to facilitate future researches. This study deals with the co-benefits and trade-offs produced by several tillage practices on SCS and related soil properties, GHG emissions, and water quality. We hypothesized that improved tillage practices could enable agriculture to contribute to SCS and mitigate GHG emissions and leaching of nutrients and pesticides. Based on our current understanding, we conclude that sustainable soil moisture level and soil temperature management is crucial under different tillage practices to offset leaching loss of soil stored nutrients/pesticides, GHG emissions and ensuring SCS. For instance, higher carbon dioxide (CO2) and nitrous oxide (N2O) emissions from conventional tillage (CT) and no-tillage (NT) could be attributed to the fluctuations in soil moisture and temperature regimes. In addition, NT may enhance nitrate (NO3-) leaching over CT because of improved soil structure, infiltration capacity, and greater water flux, however, suggesting that the eutrophication potential of NT is high. Our study indicates that the evaluation of the eutrophication potential of different tillage practices is still overlooked. Our study suggests that improving tillage practices in terms of mitigation of N2O emission and preventing NO3- pollution may be sustainable if nitrification inhibitors are applied.
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Affiliation(s)
| | | | | | - Adetomi O Adekoya
- Department of Crop Protection and Environmental Biology, University of Ibadan, Ibadan, Nigeria
| | - Gerard H Ros
- Environmental Systems Analysis Group, Wageningen University and Research, Wageningen, the Netherlands
| | - Wim de Vries
- Environmental Systems Analysis Group, Wageningen University and Research, Wageningen, the Netherlands
| | | | - Hafiz M N Iqbal
- Tecnologico de Monterrey, School of Engineering and Science, Monterrey 64849, Mexico.
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4
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Li Z, Di Gioia F, Paudel B, Zhao X, Hong J, Pisani C, Rosskopf E, Wilson P. Quantifying the effects of anaerobic soil disinfestation and other biological soil management strategies on nitrous oxide emissions from raised bed plasticulture tomato production. JOURNAL OF ENVIRONMENTAL QUALITY 2022; 51:162-180. [PMID: 34997770 DOI: 10.1002/jeq2.20324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
Soilborne pests are a major obstacle that must be overcome for the production of horticultural crops. Methyl bromide (MBr) was an effective preplanting soil broad-spectrum biocide, but its use has been banned due to its role in depleting the ozone layer. As a result, sustainable alternative methods for controlling soilborne pathogens and pests are needed. Nitrous oxide (N2 O) emissions are of concern in crop production due to the role of N2 O as a greenhouse gas. Agricultural lands are known sources for emission of N2 O into the atmosphere. Emissions are related to many environmental factors as well as fertilization and fumigation practices. This study evaluated the influence of different alternatives to MBr on N2 O emissions throughout a tomato production season in two locations representative of southern and northern Florida. We evaluated eight soil management practices, including (a) untreated controls; (b) chemical soil fumigation; (c) anaerobic soil disinfestation using molasses (M) + composted poultry litter and (d and e) M + composted yard waste (CYW, at two rates); (f) Soil Symphony Amendment (SSA), a commercially available mix of microbes and nutrients; (g) CYW alone; and (h) CYW + SSA. Nitrous oxide emissions were measured throughout the cropping season. Emissions were highest on the day of planting (Day 21), ranging from 213 to 1,878 μg m-2 h-1 , likely due to the release of N2 O that had accumulated under the totally impermeable film when it was punctured for planting. However, statistical significance varied between sites. Estimated cumulative emissions of N2 O throughout the production season ranged from 1.3 to 4.8 kg N2 O-N ha-1 .
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Affiliation(s)
- Zhuona Li
- Soil and Water Sciences Dep., Univ. of Florida/IFAS, P.O. Box 110290, Gainesville, FL, 32611-0290, USA
| | - Francesco Di Gioia
- Dep. of Plant Pathology, Univ. of Florida/IFAS, P.O. Box 110680, Gainesville, FL, 32611-0680, USA
- Dep. of Plant Science, Pennsylvania State Univ., 207 Tyson Building, University Park, PA, 16802, USA
| | - Bodh Paudel
- Dep. of Horticultural Sciences, Univ. of Florida/IFAS, P.O. Box 110690, Gainesville, FL, 32611-0690, USA
| | - Xin Zhao
- Dep. of Horticultural Sciences, Univ. of Florida/IFAS, P.O. Box 110690, Gainesville, FL, 32611-0690, USA
| | - Jason Hong
- USDA-ARS, U.S. Horticultural Research Lab., 2001 S. Rock Road, Fort Pierce, FL, 34945, USA
| | - Cristina Pisani
- USDA-ARS, Southeastern Fruit & Tree Nut Research Lab., 21 Dunbar Road, Byron, GA, 31008, USA
| | - Erin Rosskopf
- USDA-ARS, U.S. Horticultural Research Lab., 2001 S. Rock Road, Fort Pierce, FL, 34945, USA
| | - Patrick Wilson
- Soil and Water Sciences Dep., Univ. of Florida/IFAS, P.O. Box 110290, Gainesville, FL, 32611-0290, USA
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5
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Alhassan ARM, Yang C, Ma W, Li G. Influence of conservation tillage on Greenhouse gas fluxes and crop productivity in spring-wheat agroecosystems on the Loess Plateau of China. PeerJ 2021; 9:e11064. [PMID: 33954028 PMCID: PMC8048409 DOI: 10.7717/peerj.11064] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 02/14/2021] [Indexed: 12/02/2022] Open
Abstract
The effects of climate change such as dry spells, floods and erosion heavily impact agriculture especially smallholder systems on the Northwestern Loess Plateau of China. Nonetheless agriculture also contributes to global warming through the emission of greenhouse gases such as CO2, CH4 and N2O. Yet this complex conundrum can be alleviated and mitigated through sound soil and water management practices. Despite considerable literature on Conservation Agriculture (CA) as a strategy to improve the resilience and mitigation capacity of agroecosystems, there is still paucity of information on the impacts of CA on crop production and environmental quality on the Plateau. In order to fill this gap this study examined the effects of no-till and straw mulch on crop productivity and greenhouse gas fluxes in agroecosystems on the Plateau where farmers’ common practice of conventional tillage (CT) was tested against three CA practices: conventional tillage with straw mulch (CTS), no-till (NT) and no-till with straw mulch (NTS). The results indicated that all three CA practices (CTS, NT and NTS) markedly increased soil water content (SWC), soil organic carbon (SOC) and soil total nitrogen (STN) but reduced soil temperature (ST). Average grain yields were 854.46 ± 76.51, 699.30 ± 133.52 and 908.18±38.64 kg ha-1 respectively under CTS, NT and NTS indicating an increase by approximately 33%, 9% and 41% respectively compared with CT (644.61 ± 76.98 kg ha−1). There were significant (p < 0.05) reductions of Net CO2 emissions under NT (7.37 ± 0.89 tCO2e ha−1y−1) and NTS (6.65 ± 0.73 tCO2e ha-1y-1) compared with CTS (10.65 ± 0.18 tCO2e ha−1y−1) and CT (11.14 ± 0.58 tCO2e ha−1y−1). All the treatments served as sinks of CH4but NTS had the highest absorption capacity (−0.27 ± 0.024 tCO2e ha−1y−1) and increased absorption significantly (p < 0.05) compared with CT (−0.21 ± 0.017 tCO2e ha−1y−1); however, CA did not reduce emissions of N2O. These had an influence on Global warming potential (GWP) as NT and NTS resulted in significant reduction in net GWP. Grain yield was significantly correlated positively with SOC and STN (p < 0.05); ecosystem respiration was also significantly correlated with SWC and ST while CH4 flux was highly correlated with ST (p < 0.001). Crop yield and GHG responses to CA were controlled by soil hydrothermal and nutrient changes, thus improving these conditions through adoption of sustainable soil moisture improvement practices such as no-till, straw mulch, green manuring, contour ploughing and terracing can improve crop resilience to climate change and reduce GHG emissions in arid and semi-arid regions.
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Affiliation(s)
- Abdul-Rauf Malimanga Alhassan
- College of Forestry, Gansu Agricultural University, Lanzhou, Gansu, China.,Department of Water Resources and Sustainable Development, University of Environment and Sustainable Development, Somanya, Eastern Region, Ghana
| | - Chuanjie Yang
- College of Forestry, Gansu Agricultural University, Lanzhou, Gansu, China
| | - Weiwei Ma
- College of Forestry, Gansu Agricultural University, Lanzhou, Gansu, China
| | - Guang Li
- College of Forestry, Gansu Agricultural University, Lanzhou, Gansu, China
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6
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Walton CR, Zak D, Audet J, Petersen RJ, Lange J, Oehmke C, Wichtmann W, Kreyling J, Grygoruk M, Jabłońska E, Kotowski W, Wiśniewska MM, Ziegler R, Hoffmann CC. Wetland buffer zones for nitrogen and phosphorus retention: Impacts of soil type, hydrology and vegetation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 727:138709. [PMID: 32334232 DOI: 10.1016/j.scitotenv.2020.138709] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 04/09/2020] [Accepted: 04/13/2020] [Indexed: 06/11/2023]
Abstract
Wetland buffer zones (WBZs) are riparian areas that form a transition between terrestrial and aquatic environments and are well-known to remove agricultural water pollutants such as nitrogen (N) and phosphorus (P). This review attempts to merge and compare data on the nutrient load, nutrient loss and nutrient removal and/or retention from multiple studies of various WBZs termed as riparian mineral soil wetlands, groundwater-charged peatlands (i.e. fens) and floodplains. Two different soil types ('organic' and 'mineral'), four different main water sources ('groundwater', 'precipitation', 'surface runoff/drain discharge', and 'river inundation') and three different vegetation classes ('arboraceous', 'herbaceous' and 'aerenchymous') were considered separately for data analysis. The studied WBZs are situated within the temperate and continental climatic regions that are commonly found in northern-central Europe, northern USA and Canada. Surprisingly, only weak differences for the nutrient removal/retention capability were found if the three WBZ types were directly compared. The results of our study reveal that for example the nitrate retention efficiency of organic soils (53 ± 28%; mean ± sd) is only slightly higher than that of mineral soils (50 ± 32%). Variance in load had a stronger influence than soil type on the N retention in WBZs. However, organic soils in fens tend to be sources of dissolved organic N and soluble reactive P, particularly when the fens have become degraded due to drainage and past agricultural usage. The detailed consideration of water sources indicated that average nitrate removal efficiencies were highest for ground water (76 ± 25%) and lowest for river water (35 ± 24%). No significant pattern for P retention emerged; however, the highest absolute removal appeared if the P source was river water. The harvesting of vegetation will minimise potential P loss from rewetted WBZs and plant biomass yield may promote circular economy value chains and provide compensation to land owners for restored land now unsuitable for conventional farming.
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Affiliation(s)
- Craig R Walton
- Chemical Analytics and Biogeochemistry, Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin (IGB), Berlin, Germany
| | - Dominik Zak
- Chemical Analytics and Biogeochemistry, Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin (IGB), Berlin, Germany; Department of Bioscience, Aarhus University, 8600 Silkeborg, Denmark.
| | - Joachim Audet
- Department of Bioscience, Aarhus University, 8600 Silkeborg, Denmark
| | | | - Jelena Lange
- Institute of Botany and Landscape Ecology, University of Greifswald, 17487 Greifswald, Germany
| | - Claudia Oehmke
- Institute of Botany and Landscape Ecology, University of Greifswald, 17487 Greifswald, Germany
| | - Wendelin Wichtmann
- Institute of Botany and Landscape Ecology, University of Greifswald, 17487 Greifswald, Germany
| | - Jürgen Kreyling
- Institute of Botany and Landscape Ecology, University of Greifswald, 17487 Greifswald, Germany
| | - Mateusz Grygoruk
- Warsaw University of Life Sciences-SGGW, Institute of Environmental Engineering, Department of Hydrology, Meteorology and Water Management, 02-787 Warsaw, Poland
| | - Ewa Jabłońska
- Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, 02-089 Warsaw, Poland
| | - Wiktor Kotowski
- Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, 02-089 Warsaw, Poland
| | - Marta M Wiśniewska
- Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, 02-089 Warsaw, Poland
| | - Rafael Ziegler
- Getidos, University of Greifswald, 17487 Greifswald, Germany
| | - Carl C Hoffmann
- Department of Bioscience, Aarhus University, 8600 Silkeborg, Denmark
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7
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Ramzan S, Rasool T, Bhat RA, Ahmad P, Ashraf I, Rashid N, Ul Shafiq M, Mir IA. Agricultural soils a trigger to nitrous oxide: a persuasive greenhouse gas and its management. ENVIRONMENTAL MONITORING AND ASSESSMENT 2020; 192:436. [PMID: 32548706 DOI: 10.1007/s10661-020-08410-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 06/04/2020] [Indexed: 06/11/2023]
Abstract
Agricultural soils form the backbone of the country's economic development. The increased population has not only reduced this treasure but also has affected the global climate at an alarming rate. Among the GHGs, emission of N2O due to agricultural activities is nowadays a global concern. Agricultural industries have increased N2O and CH4 by 17% in the atmosphere since 1990, with an average emanation rate of around 60 MT CO2 equivalents per year. Crop production accounts for approximately 50% of N2O emissions stemming from the farming community and discharges of fertilizer-induced N2O, for the time being estimated by IPCC at 1.24% of the N used ranging from 0.76% (rice) to 2.77% (maize). The concentration of atmospheric N2O has increased (60 ppb) after the industrial revolution, at the pace of 0.73 ppb year-1. Besides, soil structure, temperature, moisture, denitrifying microbial population, pH, C:N ratio, and relief are the factors which significantly enhance the N2O levels into the atmosphere. N2O as a GHG has more potential towards global warming than CO2 and has a very long residence period (115 years) in the atmosphere. N2O emission is nowadays a core issue which needs to be mitigated so as to decline the levels of its production in agricultural soils. However, priority should be given to the organic farming, management of soil chemistry, and phytoremediation to reduce the addition of N2O into the ambient air. Furthermore, deployment of N2O reductase in agricultural soils increases the efficiency of converting N2O to inert N2 which is a valuable strategy to reduce N2O production.
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Affiliation(s)
- Shazia Ramzan
- SMS, Soil science, KVK Anantnag, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Tabasum Rasool
- Department of Civil Engineering, National Institute of Technology Srinagar Campus, Srinagar, India
| | - Rouf Ahmad Bhat
- Division of Environmental Science, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir Shalimar Campus, Srinagar, Jammu and Kashmir, India.
| | - Pervez Ahmad
- Department of Geography and Regional Development, University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Ifra Ashraf
- College of Agricultural Engineering and Technology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir Shalimar Campus, Srinagar, Jammu and Kashmir, India
| | - Nowsheeba Rashid
- Amity Institute of Food Technology, Amity University Noida, Noida, Uttar Pradesh, India
| | - Mifta Ul Shafiq
- Department of Geography and Regional, Development Climate and Cryosphere Group, University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Ikhlaq A Mir
- Division of Environmental Science Centre for climate Change, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir Shalimar Campus, Srinagar, Jammu and Kashmir, India
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8
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Schindler T, Mander Ü, Machacova K, Espenberg M, Krasnov D, Escuer-Gatius J, Veber G, Pärn J, Soosaar K. Short-term flooding increases CH 4 and N 2O emissions from trees in a riparian forest soil-stem continuum. Sci Rep 2020; 10:3204. [PMID: 32081925 PMCID: PMC7035275 DOI: 10.1038/s41598-020-60058-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 02/04/2020] [Indexed: 11/09/2022] Open
Abstract
One of the characteristics of global climate change is the increase in extreme climate events, e.g., droughts and floods. Forest adaptation strategies to extreme climate events are the key to predict ecosystem responses to global change. Severe floods alter the hydrological regime of an ecosystem which influences biochemical processes that control greenhouse gas fluxes. We conducted a flooding experiment in a mature grey alder (Alnus incana (L.) Moench) forest to understand flux dynamics in the soil-tree-atmosphere continuum related to ecosystem N2O and CH4 turn-over. The gas exchange was determined at adjacent soil-tree-pairs: stem fluxes were measured in vertical profiles using manual static chambers and gas chromatography; soil fluxes were measured with automated chambers connected to a gas analyser. The tree stems and soil surface were net sources of N2O and CH4 during the flooding. Contrary to N2O, the increase in CH4 fluxes delayed in response to flooding. Stem N2O fluxes were lower although stem CH4 emissions were significantly higher than from soil after the flooding. Stem fluxes decreased with stem height. Our flooding experiment indicated soil water and nitrogen content as the main controlling factors of stem and soil N2O fluxes. The stems contributed up to 88% of CH4 emissions to the stem-soil continuum during the investigated period but soil N2O fluxes dominated (up to 16 times the stem fluxes) during all periods. Conclusively, stem fluxes of CH4 and N2O are essential elements in forest carbon and nitrogen cycles and must be included in relevant models.
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Affiliation(s)
- Thomas Schindler
- Department of Geography, Institute of Ecology & Earth Sciences, University of Tartu, Tartu, Estonia. .,Department of Ecosystem Trace Gas Exchange, Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic.
| | - Ülo Mander
- Department of Geography, Institute of Ecology & Earth Sciences, University of Tartu, Tartu, Estonia
| | - Katerina Machacova
- Department of Ecosystem Trace Gas Exchange, Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
| | - Mikk Espenberg
- Department of Geography, Institute of Ecology & Earth Sciences, University of Tartu, Tartu, Estonia
| | - Dmitrii Krasnov
- Department of Plant Physiology, Estonian University of Life Sciences, Tartu, Estonia
| | | | - Gert Veber
- Department of Geography, Institute of Ecology & Earth Sciences, University of Tartu, Tartu, Estonia
| | - Jaan Pärn
- Department of Geography, Institute of Ecology & Earth Sciences, University of Tartu, Tartu, Estonia
| | - Kaido Soosaar
- Department of Geography, Institute of Ecology & Earth Sciences, University of Tartu, Tartu, Estonia
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9
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Liu T, Liang Y, Chu G. Nitrapyrin addition mitigates nitrous oxide emissions and raises nitrogen use efficiency in plastic-film-mulched drip-fertigated cotton field. PLoS One 2017; 12:e0176305. [PMID: 28481923 PMCID: PMC5421752 DOI: 10.1371/journal.pone.0176305] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Accepted: 04/07/2017] [Indexed: 12/04/2022] Open
Abstract
Nitrification inhibitors (NIs) have been used extensively to reduce nitrogen losses and increase crop nitrogen nutrition. However, information is still scant regarding the influence of NIs on nitrogen transformation, nitrous oxide (N2O) emission and nitrogen utilization in plastic-film-mulched calcareous soil under high frequency drip-fertigated condition. Therefore, a field trial was conducted to evaluate the effect of nitrapyrin (2-chloro-6-(trichloromethyl)-pyridine) on soil mineral nitrogen (N) transformation, N2O emission and nitrogen use efficiency (NUE) in a drip-fertigated cotton-growing calcareous field. Three treatments were established: control (no N fertilizer), urea (225 kg N ha-1) and urea+nitrapyrin (225 kg N ha-1+2.25 kg nitrapyrin ha-1). Compared with urea alone, urea plus nitrapyrin decreased the average N2O emission fluxes by 6.6–21.8% in June, July and August significantly in a drip-fertigation cycle. Urea application increased the seasonal cumulative N2O emission by 2.4 kg N ha-1 compared with control, and nitrapyrin addition significantly mitigated the seasonal N2O emission by 14.3% compared with urea only. During the main growing season, the average soil ammonium nitrogen (NH4+-N) concentration was 28.0% greater and soil nitrate nitrogen (NO3--N) concentration was 13.8% less in the urea+nitrapyrin treatment than in the urea treatment. Soil NO3--N and water-filled pore space (WFPS) were more closely correlated than soil NH4+-N with soil N2O fluxes under drip-fertigated condition (P<0.001). Compared with urea alone, urea plus nitrapyrin reduced the seasonal N2O emission factor (EF) by 32.4% while increasing nitrogen use efficiency by 10.7%. The results demonstrated that nitrapyrin addition significantly inhibited soil nitrification and maintained more NH4+-N in soil, mitigated N2O losses and improved nitrogen use efficiency in plastic-film-mulched calcareous soil under high frequency drip-fertigated condition.
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Affiliation(s)
- Tao Liu
- The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction group, College of Agriculture, Shihezi University, Shihezi, P. R. China
| | - Yongchao Liang
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, P. R. China
- * E-mail: (YCL); (GXC)
| | - Guixin Chu
- The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction group, College of Agriculture, Shihezi University, Shihezi, P. R. China
- * E-mail: (YCL); (GXC)
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10
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Harty MA, Forrestal PJ, Watson CJ, McGeough KL, Carolan R, Elliot C, Krol D, Laughlin RJ, Richards KG, Lanigan GJ. Reducing nitrous oxide emissions by changing N fertiliser use from calcium ammonium nitrate (CAN) to urea based formulations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 563-564:576-586. [PMID: 27155080 DOI: 10.1016/j.scitotenv.2016.04.120] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 04/11/2016] [Accepted: 04/17/2016] [Indexed: 06/05/2023]
Abstract
The accelerating use of synthetic nitrogen (N) fertilisers, to meet the world's growing food demand, is the primary driver for increased atmospheric concentrations of nitrous oxide (N2O). The IPCC default emission factor (EF) for N2O from soils is 1% of the N applied, irrespective of its form. However, N2O emissions tend to be higher from nitrate-containing fertilisers e.g. calcium ammonium nitrate (CAN) compared to urea, particularly in regions, which have mild, wet climates and high organic matter soils. Urea can be an inefficient N source due to NH3 volatilisation, but nitrogen stabilisers (urease and nitrification inhibitors) can improve its efficacy. This study evaluated the impact of switching fertiliser formulation from calcium ammonium nitrate (CAN) to urea-based products, as a potential mitigation strategy to reduce N2O emissions at six temperate grassland sites on the island of Ireland. The surface applied formulations included CAN, urea and urea with the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) and/or the nitrification inhibitor dicyandiamide (DCD). Results showed that N2O emissions were significantly affected by fertiliser formulation, soil type and climatic conditions. The direct N2O emission factor (EF) from CAN averaged 1.49% overall sites, but was highly variable, ranging from 0.58% to 3.81. Amending urea with NBPT, to reduce ammonia volatilisation, resulted in an average EF of 0.40% (ranging from 0.21 to 0.69%)-compared to an average EF of 0.25% for urea (ranging from 0.1 to 0.49%), with both fertilisers significantly lower and less variable than CAN. Cumulative N2O emissions from urea amended with both NBPT and DCD were not significantly different from background levels. Switching from CAN to stabilised urea formulations was found to be an effective strategy to reduce N2O emissions, particularly in wet, temperate grassland.
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Affiliation(s)
- M A Harty
- Teagasc, Environmental Research Centre, Johnstown Castle, Co., Wexford, Ireland; School of Biological Sciences, Queen's University, University Road Belfast, BT7 1NN, Northern Ireland, United Kingdom
| | - P J Forrestal
- Teagasc, Environmental Research Centre, Johnstown Castle, Co., Wexford, Ireland
| | - C J Watson
- Agri-Food and Biosciences Institute (AFBI), Newforge Lane, Belfast, BT9 5PX, Northern, Ireland; School of Biological Sciences, Queen's University, University Road Belfast, BT7 1NN, Northern Ireland, United Kingdom
| | - K L McGeough
- Agri-Food and Biosciences Institute (AFBI), Newforge Lane, Belfast, BT9 5PX, Northern, Ireland
| | - R Carolan
- Agri-Food and Biosciences Institute (AFBI), Newforge Lane, Belfast, BT9 5PX, Northern, Ireland
| | - C Elliot
- School of Biological Sciences, Queen's University, University Road Belfast, BT7 1NN, Northern Ireland, United Kingdom
| | - D Krol
- Teagasc, Environmental Research Centre, Johnstown Castle, Co., Wexford, Ireland
| | - R J Laughlin
- Agri-Food and Biosciences Institute (AFBI), Newforge Lane, Belfast, BT9 5PX, Northern, Ireland
| | - K G Richards
- Teagasc, Environmental Research Centre, Johnstown Castle, Co., Wexford, Ireland.
| | - G J Lanigan
- Teagasc, Environmental Research Centre, Johnstown Castle, Co., Wexford, Ireland
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Webster JR, Knoepp JD, Swank WT, Miniat CF. Evidence for a Regime Shift in Nitrogen Export from a Forested Watershed. Ecosystems 2016. [DOI: 10.1007/s10021-016-9974-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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12
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Tian Z, Wang JJ, Liu S, Zhang Z, Dodla SK, Myers G. Application effects of coated urea and urease and nitrification inhibitors on ammonia and greenhouse gas emissions from a subtropical cotton field of the Mississippi delta region. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 533:329-338. [PMID: 26172600 DOI: 10.1016/j.scitotenv.2015.06.147] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 06/21/2015] [Accepted: 06/30/2015] [Indexed: 06/04/2023]
Abstract
Nitrogen (N) fertilization affects both ammonia (NH3) and greenhouse gas (GHG) emissions that have implications in air quality and global warming potential. Different cropping systems practice varying N fertilizations. The aim of this study was to investigate the effects of applications of polymer-coated urea and urea treated with N process inhibitors: NBPT [N-(n-butyl)thiophosphoric triamide], urease inhibitor, and DCD [Dicyandiamide], nitrification inhibitor, on NH3 and GHG emissions from a cotton production system in the Mississippi delta region. A two-year field experiment consisting of five treatments including the Check (unfertilized), urea, polymer-coated urea (ESN), urea+NBPT, and urea+DCD was conducted over 2013 and 2014 in a Cancienne loam (Fine-silty, mixed, superactive, nonacid, hyperthermic Fluvaquentic Epiaquepts). Ammonia and GHG samples were collected using active and passive chamber methods, respectively, and characterized. The results showed that the N loss to the atmosphere following urea-N application was dominated by a significantly higher emission of N2O-N than NH3-N and the most N2O-N and NH3-N emissions were during the first 30-50 days. Among different N treatments compared to regular urea, NBPT was the most effective in reducing NH3-N volatilization (by 58-63%), whereas DCD the most significant in mitigating N2O-N emissions (by 75%). Polymer-coated urea (ESN) and NBPT also significantly reduced N2O-N losses (both by 52%) over urea. The emission factors (EFs) for urea, ESN, urea-NBPT, urea+DCD were 1.9%, 1.0%, 0.2%, 0.8% for NH3-N, and 8.3%, 3.4%, 3.9%, 1.0% for N2O-N, respectively. There were no significant effects of different N treatments on CO2-C and CH4-C fluxes. Overall both of these N stabilizers and polymer-coated urea could be used as a mitigation strategy for reducing N2O emission while urease inhibitor NBPT for reducing NH3 emission in the subtropical cotton production system of the Mississippi delta region.
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Affiliation(s)
- Zhou Tian
- College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi, China; School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA
| | - Jim J Wang
- School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA.
| | - Shuai Liu
- College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi, China; School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA
| | - Zengqiang Zhang
- College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi, China.
| | - Syam K Dodla
- School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA
| | - Gerald Myers
- School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA
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13
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Deng Q, Hui D, Wang J, Iwuozo S, Yu CL, Jima T, Smart D, Reddy C, Dennis S. Corn Yield and Soil Nitrous Oxide Emission under Different Fertilizer and Soil Management: A Three-Year Field Experiment in Middle Tennessee. PLoS One 2015; 10:e0125406. [PMID: 25923716 PMCID: PMC4414621 DOI: 10.1371/journal.pone.0125406] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 03/23/2015] [Indexed: 11/18/2022] Open
Abstract
Background A three-year field experiment was conducted to examine the responses of corn yield and soil nitrous oxide (N2O) emission to various management practices in middle Tennessee. Methodology/Principal Findings The management practices include no-tillage + regular applications of urea ammonium nitrate (NT-URAN); no-tillage + regular applications of URAN + denitrification inhibitor (NT-inhibitor); no-tillage + regular applications of URAN + biochar (NT-biochar); no-tillage + 20% applications of URAN + chicken litter (NT-litter), no-tillage + split applications of URAN (NT-split); and conventional tillage + regular applications of URAN as a control (CT-URAN). Fertilizer equivalent to 217 kg N ha-1 was applied to each of the experimental plots. Results showed that no-tillage (NT-URAN) significantly increased corn yield by 28% over the conventional tillage (CT-URAN) due to soil water conservation. The management practices significantly altered soil N2O emission, with the highest in the CT-URAN (0.48 mg N2O m-2 h-1) and the lowest in the NT-inhibitor (0.20 mg N2O m-2 h-1) and NT-biochar (0.16 mg N2O m-2 h-1) treatments. Significant exponential relationships between soil N2O emission and water filled pore space were revealed in all treatments. However, variations in soil N2O emission among the treatments were positively correlated with the moisture sensitivity of soil N2O emission that likely reflects an interactive effect between soil properties and WFPS. Conclusion/Significance Our results indicated that improved fertilizer and soil management have the potential to maintain highly productive corn yield while reducing greenhouse gas emissions.
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Affiliation(s)
- Qi Deng
- College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America
| | - Dafeng Hui
- College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America
- * E-mail:
| | - Junming Wang
- Climate Science Section, Illinois State Water Survey, Prairie Research Institute, University of Illinois at Urbana-Champaign, Champaign, Illinois 61802, United States of America
| | - Stephen Iwuozo
- College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America
| | - Chih-Li Yu
- College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America
| | - Tigist Jima
- College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America
| | - David Smart
- Department of Viticulture and Enology, University of California Davis, Davis, California 95616, United States of America
| | - Chandra Reddy
- College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America
| | - Sam Dennis
- College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America
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15
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Blaser WJ, Shanungu GK, Edwards PJ, Olde Venterink H. Woody encroachment reduces nutrient limitation and promotes soil carbon sequestration. Ecol Evol 2014; 4:1423-38. [PMID: 24834338 PMCID: PMC4020701 DOI: 10.1002/ece3.1024] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Revised: 01/29/2014] [Accepted: 02/17/2014] [Indexed: 11/30/2022] Open
Abstract
During the past century, the biomass of woody species has increased in many grassland and savanna ecosystems. As many of these species fix nitrogen symbiotically, they may alter not only soil nitrogen (N) conditions but also those of phosphorus (P). We studied the N-fixing shrub Dichrostachys cinerea in a mesic savanna in Zambia, quantifying its effects upon pools of soil N, P, and carbon (C), and availabilities of N and P. We also evaluated whether these effects induced feedbacks upon the growth of understory vegetation and encroaching shrubs. Dichrostachys cinerea shrubs increased total N and P pools, as well as resin-adsorbed N and soil extractable P in the top 10-cm soil. Shrubs and understory grasses differed in their foliar N and P concentrations along gradients of increasing encroachment, suggesting that they obtained these nutrients in different ways. Thus, grasses probably obtained them mainly from the surface upper soil layers, whereas the shrubs may acquire N through symbiotic fixation and probably obtain some of their P from deeper soil layers. The storage of soil C increased significantly under D. cinerea and was apparently not limited by shortages of either N or P. We conclude that the shrub D. cinerea does not create a negative feedback loop by inducing P-limiting conditions, probably because it can obtain P from deeper soil layers. Furthermore, C sequestration is not limited by a shortage of N, so that mesic savanna encroached by this species could represent a C sink for several decades. We studied the effects of woody encroachment on soil N, P, and C pools, and availabilities of N and P to Dichrostachys cinerea shrubs and to the understory vegetation. Both N and P pools in the soil increased along gradients of shrub age and cover, suggesting that N fixation by D. cinerea did not reduce the P supply. This in turn suggests that continued growth and carbon sequestration in this mesic savanna ecosystems are unlikely to be constrained by nutrient limitation and could represent a C sink for several decades.
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Affiliation(s)
- Wilma J Blaser
- Institute of Integrative Biology, ETH Zurich Universitaetsstrasse 16, 8092, Zurich, Switzerland
| | | | - Peter J Edwards
- Institute of Integrative Biology, ETH Zurich Universitaetsstrasse 16, 8092, Zurich, Switzerland
| | - Harry Olde Venterink
- Institute of Integrative Biology, ETH Zurich Universitaetsstrasse 16, 8092, Zurich, Switzerland
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16
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Rena YG, Wang JH, Li HF, Zhang J, Qi PY, Hu Z. Nitrous oxide and methane emissions from different treatment processes in full-scale municipal wastewater treatment plants. ENVIRONMENTAL TECHNOLOGY 2013; 34:2917-2927. [PMID: 24617051 DOI: 10.1080/09593330.2012.696717] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Nitrous oxide (N2O) and methane (CH4) are two important greenhouse gases (GHG) emitted from biological nutrient removal (BNR) processes in municipal wastewater treatment plants (WWTP). In this study, three typical biological wastewater treatment processes were studied in WWTP of Northern China: pre-anaerobic carrousel oxidation ditch (A+OD) process, pre-anoxic anaerobic-anoxic-oxic (A-A/ A/O) process and reverse anaerobic-anoxic-oxic (r-A/ A/O) process. The N2O and CH4 emissions from these three different processes were measured in every processing unit of each WWTP. Results showed that N2O and CH4 were mainly discharged during the nitrification/denitrification process and the anaerobic/anoxic treatment process, respectively and the amounts of their formation and release were significantly influenced by different BNR processes implemented in these WWTP. The N2O conversion ratio of r-A/ A/O process was the lowest among the three WWTP, which were 10.9% and 18.6% lower than that of A-A/A/O process and A+OD process, respectively. Similarly, the CH4 conversion ratio of r-A/ A/O process was the lowest among the three WWTP, which were 89. I% and 80.8% lower than that of A-A/ A/O process and A+OD process, respectively. The factors influencing N2O and CH4 formation and emission in the three WWTP were investigated to explain the difference between these processes. The nitrite concentration and oxidation-reduction potential (ORP) value were found to be the dominant influencing factors affecting N2O and CH4 production, respectively. The flow-based emission factors of N2O and CH4 of the WWTP were figured out for better quantification of GHG emissions and further technical assessments of mitigation options.
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17
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Keville MP, Reed SC, Cleveland CC. Nitrogen cycling responses to mountain pine beetle disturbance in a high elevation whitebark pine ecosystem. PLoS One 2013; 8:e65004. [PMID: 23755166 PMCID: PMC3673984 DOI: 10.1371/journal.pone.0065004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 04/23/2013] [Indexed: 11/20/2022] Open
Abstract
Ecological disturbances can significantly affect biogeochemical cycles in terrestrial ecosystems, but the biogeochemical consequences of the extensive mountain pine beetle outbreak in high elevation whitebark pine (WbP) (Pinus albicaulis) ecosystems of western North America have not been previously investigated. Mountain pine beetle attack has driven widespread WbP mortality, which could drive shifts in both the pools and fluxes of nitrogen (N) within these ecosystems. Because N availability can limit forest regrowth, understanding how beetle-induced mortality affects N cycling in WbP stands may be critical to understanding the trajectory of ecosystem recovery. Thus, we measured above- and belowground N pools and fluxes for trees representing three different times since beetle attack, including unattacked trees. Litterfall N inputs were more than ten times higher under recently attacked trees compared to unattacked trees. Soil inorganic N concentrations also increased following beetle attack, potentially driven by a more than two-fold increase in ammonium (NH4+) concentrations in the surface soil organic horizon. However, there were no significant differences in mineral soil inorganic N or soil microbial biomass N concentrations between attacked and unattacked trees, implying that short-term changes in N cycling in response to the initial stages of WbP attack were restricted to the organic horizon. Our results suggest that while mountain pine beetle attack drives a pulse of N from the canopy to the forest floor, changes in litterfall quality and quantity do not have profound effects on soil biogeochemical cycling, at least in the short-term. However, continuous observation of these important ecosystems will be crucial to determining the long-term biogeochemical effects of mountain pine beetle outbreaks.
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Affiliation(s)
- Megan P. Keville
- Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, Montana, United States of America
| | - Sasha C. Reed
- U.S. Geological Survey, Southwest Biological Science Center, Moab, Utah, United States of America
| | - Cory C. Cleveland
- Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, Montana, United States of America
- * E-mail:
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18
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Morse JL, Ardón M, Bernhardt ES. Using environmental variables and soil processes to forecast denitrification potential and nitrous oxide fluxes in coastal plain wetlands across different land uses. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jg001923] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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19
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Rudaz AO, Davidson EA, Firestone MK. Sources of nitrous oxide production following wetting of dry soil. FEMS Microbiol Ecol 2011. [DOI: 10.1111/j.1574-6941.1991.tb01715.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Suddick EC, Steenwerth K, Garland GM, Smart DR, Six J. Discerning Agricultural Management Effects on Nitrous Oxide Emissions from Conventional and Alternative Cropping Systems: A California Case Study. ACS SYMPOSIUM SERIES 2011. [DOI: 10.1021/bk-2011-1072.ch012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- E. C. Suddick
- Department of Plant Sciences, University of California, Davis, CA, 95616
- USDA/ARS, Crops Pathology and Genetics Research Unit, Davis, CA 95616
- Department of Viticulture and Enology, University of California, Davis, CA, 95616
| | - K. Steenwerth
- Department of Plant Sciences, University of California, Davis, CA, 95616
- USDA/ARS, Crops Pathology and Genetics Research Unit, Davis, CA 95616
- Department of Viticulture and Enology, University of California, Davis, CA, 95616
| | - G. M. Garland
- Department of Plant Sciences, University of California, Davis, CA, 95616
- USDA/ARS, Crops Pathology and Genetics Research Unit, Davis, CA 95616
- Department of Viticulture and Enology, University of California, Davis, CA, 95616
| | - D. R. Smart
- Department of Plant Sciences, University of California, Davis, CA, 95616
- USDA/ARS, Crops Pathology and Genetics Research Unit, Davis, CA 95616
- Department of Viticulture and Enology, University of California, Davis, CA, 95616
| | - J. Six
- Department of Plant Sciences, University of California, Davis, CA, 95616
- USDA/ARS, Crops Pathology and Genetics Research Unit, Davis, CA 95616
- Department of Viticulture and Enology, University of California, Davis, CA, 95616
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Ardón M, Morse JL, Doyle MW, Bernhardt ES. The Water Quality Consequences of Restoring Wetland Hydrology to a Large Agricultural Watershed in the Southeastern Coastal Plain. Ecosystems 2010. [DOI: 10.1007/s10021-010-9374-x] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Kusel K, Drake HL. Effects of environmental parameters on the formation and turnover of acetate by forest soils. Appl Environ Microbiol 2010; 61:3667-75. [PMID: 16535147 PMCID: PMC1388709 DOI: 10.1128/aem.61.10.3667-3675.1995] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The capacity to form acetate from endogenous matter was a common property of diverse forest soils when incubated under anaerobic conditions. At 15 to 20(deg)C, acetate synthesis occurred without appreciable delay when forest soils were incubated as buffered suspensions or in microcosms at various percentages of their maximum water holding capacity. Rates for acetate formation with soil suspensions ranged from 35 to 220 (mu)g of acetate per g (dry weight) of soil per 24 h, and maximal acetate concentrations obtained in soil suspensions were two- to threefold greater than those obtained with soil microcosms at the average water holding capacity of the soil. Cellobiose degradation in soil suspensions yielded H(inf2) as a transient product. Under anaerobic conditions, supplemental H(inf2) and CO(inf2) were directed towards the acetogenic synthesis of acetate, and enrichments yielded a syringate-H(inf2)-consuming acetogenic consortium. At in situ temperatures, acetate was a relatively stable anaerobic end product; however, extended incubation periods induced acetoclastic methanogenesis and sulfate reduction. Higher mesophilic and thermophilic temperatures greatly enhanced the capacity of soils to form methane. Although methanogenic and sulfate-reducing activities under in situ-relevant conditions were negligible, these findings nonetheless demonstrated the occurrence of methanogens and sulfate-reducing bacteria in these aerated terrestrial soils. In contrast to the protracted stability of acetate under anaerobic conditions at 15 to 20(deg)C with unsupplemented soils, acetate formed by forest soils was rapidly consumed in the presence of oxygen and nitrate, and substrate-product stoichiometries indicated that acetate turnover was coupled to oxygen-dependent respiration and denitrification. The collective results suggest that acetate formed under anaerobic conditions might constitute a trophic link between anaerobic and aerobic processes in forest soils.
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Davidson EA, Swank WT. Environmental Parameters Regulating Gaseous Nitrogen Losses from Two Forested Ecosystems via Nitrification and Denitrification. Appl Environ Microbiol 2010; 52:1287-92. [PMID: 16347234 PMCID: PMC239223 DOI: 10.1128/aem.52.6.1287-1292.1986] [Citation(s) in RCA: 130] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Gaseous N losses from disturbed and reference forested watersheds at the Coweeta Hydrologic Laboratory in western North Carolina were studied by in situ N(2)O diffusion measurements and laboratory incubations throughout a 10-month period. Soil temperature, percent base saturation, and water-filled pore space accounted for 43% of the variation in in situ N(2)O diffusion measurements. Laboratory incubations distinguished the gaseous N products of nitrification and denitrification. Nitrifying activity, ambient NO(3), and nitrification N(2)O were positively correlated with percent base saturation. However, differences between watersheds in soil N substrate caused by presence of leguminous black locust in the disturbed watershed were confounded with differences in soil acidity. Denitrification was most strongly affected by soil moisture, which in turn was determined by precipitation events and slope position. Gaseous N losses from well-drained midslope and toeslope landscape positions appeared to be minor relative to other N transformations. Favorable conditions for denitrification occurred at a poorly drained site near the stream of the disturbed watershed. Laboratory incubations revealed high rates of NO(3) reduction in these soils. We speculate that the riparian zone is a major site of depletion of NO(3) from the soil solution via denitrification.
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Affiliation(s)
- E A Davidson
- Department of Forestry, North Carolina State University, Raleigh, North Carolina 27695-8002, and U.S. Department of Agriculture Forest Service Southeastern Experiment Station, Coweeta Hydrologic Laboratory, Otto, North Carolina 28763
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Szukics U, Abell GCJ, Hödl V, Mitter B, Sessitsch A, Hackl E, Zechmeister-Boltenstern S. Nitrifiers and denitrifiers respond rapidly to changed moisture and increasing temperature in a pristine forest soil. FEMS Microbiol Ecol 2010; 72:395-406. [PMID: 20298502 DOI: 10.1111/j.1574-6941.2010.00853.x] [Citation(s) in RCA: 191] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Complete cycling of mineral nitrogen (N) in soil requires the interplay of microorganisms performing nitrification and denitrification, whose activity is increasingly affected by extreme rainfall or heat brought about by climate change. In a pristine forest soil, a gradual increase in soil temperature from 5 to 25 degrees C in a range of water contents stimulated N turnover rates, and N gas emissions were determined by the soil water-filled pore space (WFPS). NO and N(2)O emissions dominated at 30% WFPS and 55% WFPS, respectively, and the step-wise temperature increase resulted in a threefold increase in the NO(3)(-) concentrations and a decrease in the NH(4)(+) concentration. At 70% WFPS, NH(4)(+) accumulated while NO(3)(-) pools declined, indicating gaseous N loss. AmoA- and nirK-gene-based analysis revealed increasing abundance of bacterial ammonia oxidizers (AOB) with increasing soil temperature and a decrease in the abundance of archaeal ammonia oxidizers (AOA) in wet soil at 25 degrees C, suggesting the sensitivity of the latter to anaerobic conditions. Denitrifier (nirK) community structure was most affected by the water content and nirK gene abundance rapidly increased in response to wet conditions until the substrate (NO(3)(-)) became limiting. Shifts in the community structure were most pronounced for nirK and most rapid for AOA, indicating dynamic populations, whereas distinct adaptation of the AOB communities required 5 weeks, suggesting higher stability.
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Affiliation(s)
- Ute Szukics
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Seibersdorf, Austria.
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25
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Pratt WA, Fox TR. Streamside management zones effectiveness for protecting water quality after forestland application of biosolids. JOURNAL OF ENVIRONMENTAL QUALITY 2009; 38:2106-2120. [PMID: 19704153 DOI: 10.2134/jeq2008.0350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Biosolids, materials resulting from domestic sewage treatment, are surface applied to forest soils to increase phosphorus (P), nitrate, and ammonium availability. Retaining streamside management zones (SMZs) can limit nutrient pollution of streams. We delineated 15-m SMZs along three intermittent streams in an 18-yr-old Pinus taeda L. plantation. We applied biosolids at a rate of 1120 and 629 kg ha(-1) of total nitrogen and total P outside the SMZ on one side of each of the streams while maintaining the other side of the stream as control. We collected water samples from the three treated and six reference streams and from the perennial stream upstream and downstream from the intermittent streams for 12 mo after treatment. Along transects perpendicular to the treated streams, we collected overland flow samples, soil solution samples at 60 cm, and extracts from ion exchange membranes (IEMs) placed in the surface soil. We observed significantly elevated P concentrations adjacent to the stream in overland flow during one period on the treated side of the stream. We found significantly elevated nitrate concentrations outside the SMZ in the treated-side soil solution samples, in which concentrations remained below 1.5 mg L(-1). Phosphorus, nitrate, and ammonium concentrations outside the SMZ in treated-side IEM extracts showed significant increases after biosolids application, returning to near control levels after 1 yr. Phosphorus, nitrate, and ammonium concentrations in IEM extracts were not different adjacent to the streams. Stream P, nitrate, and ammonium concentrations showed few differences downstream from the treatment with concentrations below 1.5 mg L(-1). Our results indicate that at 15 m, SMZ protected streams from P, nitrate, and ammonium pollution for the first year after biosolids application to adjacent loblolly pine plantations in the Virginia Piedmont.
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Affiliation(s)
- W A Pratt
- Dep. of Forestry, Virginia Polytechnic Institute and State Univ., Blacksburg, VA 24061, USA.
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26
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Griffiths RP, Filan T. Effects of Bracken Fern Invasions on Harvested Site Soils in Pacific Northwest (USA) Coniferous Forests. NORTHWEST SCIENCE 2007. [DOI: 10.3955/0029-344x-81.3.191] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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27
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Osaka K, Ohte N, Koba K, Katsuyama M, Nakajima T. Hydrologic controls on nitrous oxide production and consumption in a forested headwater catchment in central Japan. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jg000026] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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28
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Robinson MA, Reay WG. Ground water flow analysis of a mid-Atlantic outer coastal plain watershed, Virginia, U.S.A. GROUND WATER 2002; 40:123-131. [PMID: 11916117 DOI: 10.1111/j.1745-6584.2002.tb02497.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Models for ground water flow (MODFLOW) and particle tracking (MODPATH) were used to determine ground water flow patterns, principal ground water discharge and recharge zones, and estimates of ground water travel times in an unconfined ground water system of an outer coastal plain watershed on the Delmarva Peninsula, Virginia. By coupling recharge and discharge zones within the watershed, flowpath analysis can provide a method to locate and implement specific management strategies within a watershed to reduce ground water nitrogen loading to surface water. A monitoring well network was installed in Eyreville Creek watershed, a first-order creek, to determine hydraulic conductivities and spatial and temporal variations in hydraulic heads for use in model calibration. Ground water flow patterns indicated the convergence of flow along the four surface water features of the watershed; primary discharge areas were in the nontidal portions of the watershed. Ground water recharge zones corresponded to the surface water features with minimal development of a regional ground water system. Predicted ground water velocities varied between < 0.01 to 0.24 m/day, with elevated values associated with discharge areas and areas of convergence along surface water features. Some ground water residence times exceeded 100 years, although average residence times ranged between 16 and 21 years; approximately 95% of the ground water resource would reflect land use activities within the last 50 years.
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Affiliation(s)
- Michael A Robinson
- College of Information Technology and Engineering, Marshall University, Huntington, WV 25755-2586, USA.
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29
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Härtel E, Zechmeister-Boltenstern S, Gerzabck M. Gaseous nitrogen losses from a forest site in the North Tyrolean Limestone Alps. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2002; Spec No 2:23-30. [PMID: 12638757 DOI: 10.1007/bf02987474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Microorganisms are responsible for the mineralisation of organic nitrogen in soils. NH4+ can be further oxidised to NO3- during nitrification and NO3- can be reduced to gaseous nitrogen compounds during denitrification. During both processes, nitrous oxide (N2O), which is known as greenhouse gas, can be lost from the ecosystem. The aim of this study was to quantify N2O emissions and the internal microbial N cycle including net N mineralisation and net nitrification in a montane forest ecosystem in the North Tyrolean Limestone Alps during an 18-month measurement period and to estimate the importance of these fluxes in comparison with other components of the N cycle. Gas samples were taken every 2 weeks using the closed chamber method. Additionally, CO2 emission rates were measured to estimate soil respiration activity. Net mineralisation and net nitrification rates were determined by the buried bag method every month. Ion exchange resin bags were used to determine the N availability in the root zone. Mean N2O emission rate was 0.9 kg N ha(-1) a(-1), which corresponds to 5% of the N deposited in the forest ecosystem. The main influencing factors were air and soil temperature and NO3- accumulated on the ion exchange resin bags. In the course of net ammonification, 14 kg NH4+-N ha(-1) were produced per year. About the same amount of NO3--N was formed during nitrification, indicating a rather complete nitrification going on at the site. NO3- concentrations found on the ion exchange resin bags were about 3 times as high as NO3- produced during net nitrification, indicating substantial NO3- immobilisation. The results of this study indicate significant nitrification activities taking place at the Mühleggerköpfl.
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Affiliation(s)
- Elisabeth Härtel
- Institute for Landscape Architecture and Landscape Management, University for Agricultural Sciences, A-1190 Vienna, Austria.
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30
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Maddock JEL, dos Santos MBP, Prata KR. Nitrous oxide emission from soil of the Mata Atlantica, Rio de Janeiro State, Brazil. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000jd000126] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Chestnut TJ, McDowell WH. C and N dynamics in the riparian and hyporheic zones of a tropical stream, Luquillo Mountains, Puerto Rico. ACTA ACUST UNITED AC 2000. [DOI: 10.2307/1468065] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Tamara J. Chestnut
- Department of Natural Resources, University of New Hampshire, 215 James Hall, Durham, New Hampshire 03824-3589 USA
| | - William H. McDowell
- Department of Natural Resources, University of New Hampshire, 215 James Hall, Durham, New Hampshire 03824-3589 USA
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32
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Beeinflussung der Wasserqualität in einem bewaldeten Einzugsgebiet durch biogeochemische Stoffumsetzungen in bachnahen Böden. ACTA ACUST UNITED AC 1999. [DOI: 10.1007/bf02768998] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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33
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Roelle P, Aneja VP, O'Connor J, Robarge W, Kim DS, Levine JS. Measurement of nitrogen oxide emissions from an agricultural soil with a dynamic chamber system. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/98jd01202] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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34
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Matthies C, Erhard HP, Drake HL. Effects of pH on the comparative culturability of fungi and bacteria from acidic and less acidic forest soils. J Basic Microbiol 1997. [DOI: 10.1002/jobm.3620370506] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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35
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Papen H, von Berg R, Hinkel I, Thoene B, Rennenberg H. Heterotrophic nitrification by Alcaligenes faecalis: NO2-, NO3-, N2O, and NO production in exponentially growing cultures. Appl Environ Microbiol 1989; 55:2068-72. [PMID: 2782877 PMCID: PMC203004 DOI: 10.1128/aem.55.8.2068-2072.1989] [Citation(s) in RCA: 136] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Heterotrophic nitrification by Alcaligenes faecalis DSM 30030 was not restricted to media containing organic forms of nitrogen. In both peptone-meat extract and defined media with ammonium and citrate as the sole nitrogen and carbon sources, respectively, NO2-, NO3-, NO, and N2O were produced under aerobic growth conditions. Heterotrophic nitrification was not attributable to old or dying cell populations. Production of NO2-, NO3-, NO, and N2O was detectable shortly after cultures started growth and proceeded exponentially during the logarithmic growth phase. NO2- and NO3- production rates were higher for cultures inoculated in media with pH values below 7 than for those in media at alkaline pH. Neither assimilatory nor dissimilatory nitrate or nitrite reductase activities were detectable in aerobic cultures.
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Affiliation(s)
- H Papen
- Fraunhofer-Institute for Atmospheric Environmental Research, Garmisch-Partenkirchen, Federal Republic of Germany
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36
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Davidson EA, Swank WT, Perry TO. Distinguishing between Nitrification and Denitrification as Sources of Gaseous Nitrogen Production in Soil. Appl Environ Microbiol 1986; 52:1280-6. [PMID: 16347233 PMCID: PMC239222 DOI: 10.1128/aem.52.6.1280-1286.1986] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The source of N
2
O produced in soil is often uncertain because denitrification and nitrification can occur simultaneously in the same soil aggregate. A technique which exploits the differential sensitivity of these processes to C
2
H
2
inhibition is proposed for distinguishing among gaseous N losses from soils. Denitrification N
2
O was estimated from 24-h laboratory incubations in which nitrification was inhibited by 10-Pa C
2
H
2
. Nitrification N
2
O was estimated from the difference between N
2
O production under no C
2
H
2
and that determined for denitrification. Denitrification N
2
was estimated from the difference between N
2
O production under 10-kPa C
2
H
2
and that under 10 Pa. Laboratory estimates of N
2
O production were significantly correlated with in situ N
2
O diffusion measurements made during a 10-month period in two forested watersheds. Nitrous oxide production from nitrification was most important on well-drained sites of a disturbed watershed where ambient NO
3
−
was high. In contrast, denitrification N
2
O was most important on poorly drained sites near the stream of the same watershed. Distinction between N
2
O production from nitrification and denitrification was corroborated by correlations between denitrification N
2
O and water-filled pore space and between nitrification N
2
O and ambient NO
3
−
. This technique permits qualitative study of environmental parameters that regulate gaseous N losses via denitrification and nitrification.
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Affiliation(s)
- E A Davidson
- Department of Forestry, North Carolina State University, Raleigh, North Carolina 27695-8002, and U.S. Department of Agriculture Forest Service Southeastern Experiment Station, Coweeta Hydrologic Laboratory, Otto, North Carolina 28763
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