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Deng N, Gubry-Rangin C, Song XT, Ju XT, Liu SY, Shen JP, Di HJ, Han LL, Zhang LM. AOB Nitrosospira cluster 3a.2 (D11) dominates N 2O emissions in fertilised agricultural soils. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 355:120504. [PMID: 38447513 DOI: 10.1016/j.jenvman.2024.120504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Revised: 02/20/2024] [Accepted: 02/25/2024] [Indexed: 03/08/2024]
Abstract
Ammonia-oxidation process directly contribute to soil nitrous oxide (N2O) emissions in agricultural soils. However, taxonomy of the key nitrifiers (within ammonia oxidising bacteria (AOB), archaea (AOA) and complete ammonia oxidisers (comammox Nitrospira)) responsible for substantial N2O emissions in agricultural soils is unknown, as is their regulation by soil biotic and abiotic factors. In this study, cumulative N2O emissions, nitrification rates, abundance and community structure of nitrifiers were investigated in 16 agricultural soils from major crop production regions of China using microcosm experiments with amended nitrogen (N) supplemented or not with a nitrification inhibitor (nitrapyrin). Key nitrifier groups involved in N2O emissions were identified by comparative analyses of the different treatments, combining sequencing and random forest analyses. Soil cumulative N2O emissions significantly increased with soil pH in all agricultural soils. However, they decreased with soil organic carbon (SOC) in alkaline soils. Nitrapyrin significantly inhibited soil cumulative N2O emissions and AOB growth, with a significant inhibition of the AOB Nitrosospira cluster 3a.2 (D11) abundance. One Nitrosospira multiformis-like OTU phylotype (OTU34), which was classified within the AOB Nitrosospira cluster 3a.2 (D11), had the greatest importance on cumulative N2O emissions and its growth significantly depended on soil pH and SOC contents, with higher growth at high pH and low SOC conditions. Collectively, our results demonstrate that alkaline soils with low SOC contents have high N2O emissions, which were mainly driven by AOB Nitrosospira cluster 3a.2 (D11). Nitrapyrin can efficiently reduce nitrification-related N2O emissions by inhibiting the activity of AOB Nitrosospira cluster 3a.2 (D11). This study advances our understanding of key nitrifiers responsible for high N2O emissions in agricultural soils and their controlling factors, and provides vital knowledge for N2O emission mitigation in agricultural ecosystems.
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Affiliation(s)
- Na Deng
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | | | - Xiao-Tong Song
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085, China
| | - Xiao-Tang Ju
- School of Tropical Agriculture and Forestry, Hainan University, Haikou, 570228, China
| | - Si-Yi Liu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085, China
| | - Ju-Pei Shen
- Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, 350007, China
| | - Hong-Jie Di
- Centre for Soil and Environmental Research, Lincoln University, Lincoln, 7647, Christchurch, New Zealand
| | - Li-Li Han
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085, China
| | - Li-Mei Zhang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
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Button ES, Marsden KA, Nightingale PD, Dixon ER, Chadwick DR, Jones DL, Cárdenas LM. Separating N 2O production and consumption in intact agricultural soil cores at different moisture contents and depths. EUROPEAN JOURNAL OF SOIL SCIENCE 2023; 74:e13363. [PMID: 38529015 PMCID: PMC10962597 DOI: 10.1111/ejss.13363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 03/29/2023] [Accepted: 04/01/2023] [Indexed: 03/27/2024]
Abstract
Agricultural soils are a major source of the potent greenhouse gas and ozone depleting substance, N2O. To implement management practices that minimize microbial N2O production and maximize its consumption (i.e., complete denitrification), we must understand the interplay between simultaneously occurring biological and physical processes, especially how this changes with soil depth. Meaningfully disentangling of these processes is challenging and typical N2O flux measurement techniques provide little insight into subsurface mechanisms. In addition, denitrification studies are often conducted on sieved soil in altered O2 environments which relate poorly to in situ field conditions. Here, we developed a novel incubation system with headspaces both above and below the soil cores and field-relevant O2 concentrations to better represent in situ conditions. We incubated intact sandy clay loam textured agricultural topsoil (0-10 cm) and subsoil (50-60 cm) cores for 3-4 days at 50% and 70% water-filled pore space, respectively. 15N-N2O pool dilution and an SF6 tracer were injected below the cores to determine the relative diffusivity and the net N2O emission and gross N2O emission and consumption fluxes. The relationship between calculated fluxes from the below and above soil core headspaces confirmed that the system performed well. Relative diffusivity did not vary with depth, likely due to the preservation of preferential flow pathways in the intact cores. Gross N2O emission and uptake also did not differ with depth but were higher in the drier cores, contrary to expectation. We speculate this was due to aerobic denitrification being the primary N2O consuming process and simultaneously occurring denitrification and nitrification both producing N2O in the drier cores. We provide further evidence of substantial N2O consumption in drier soil but without net negative N2O emissions. The results from this study are important for the future application of the 15N-N2O pool dilution method and N budgeting and modelling, as required for improving management to minimize N2O losses.
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Affiliation(s)
- Erik S. Button
- School of Natural SciencesBangor UniversityBangorGwyneddUK
| | | | - Philip D. Nightingale
- Plymouth Marine Laboratory, Prospect Pl, Marine Biogeochemical ObservationsPlymouthDevonUK
| | - Elizabeth R. Dixon
- Rothamsted Research North Wyke, Net Zero and Resilient FarmingOkehamptonDevonUK
| | | | - David L. Jones
- School of Natural SciencesBangor UniversityBangorGwyneddUK
- Centre for Sustainable Farming Systems, Food Futures InstituteMurdochWestern AustraliaAustralia
| | - Laura M. Cárdenas
- Rothamsted Research North Wyke, Net Zero and Resilient FarmingOkehamptonDevonUK
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Iqbal MF, Zhang Y, Kong P, Wang Y, Cao K, Zhao L, Xiao X, Fan X. High-yielding nitrate transporter cultivars also mitigate methane and nitrous oxide emissions in paddy. FRONTIERS IN PLANT SCIENCE 2023; 14:1133643. [PMID: 36909410 PMCID: PMC9992815 DOI: 10.3389/fpls.2023.1133643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Development of high yield rice varieties is critical to ensuring global food security. However, the emission of greenhouse gases (GHG) such as Methane (CH4) and Nitrous oxide (N2O) from paddy fields threatens environmental sustainability. In this study, we selected overexpressed high-affinity nitrate transporters (NRT2.3 along with their partner protein NAR2.1) cultivars, which are effective nitrogen use efficient transgenic lines pOsNAR2.1: OsNAR2.1 (Ox2) and p35S:OsNRT2.3b (O8). We used high (270 kg N/ha) and low (90 kg N/ha) nitrogen (N) fertilizers in paddy fields to evaluate morphophysiological traits, including GHG emission. We found that Ox2 and O8 reduced CH4 emissions by 40% and 60%, respectively, compared to their wild type (WT). During growth stages, there was no consistent N2O discharge pattern between WT and transgenics (Ox2, O8) in low and high N application. However, total cumulative N2O in a cropping season reduced in O8 and increased in Ox2 cultivars, compared to WT. Root aerenchyma formation reduced by 30-60% in transgenic lines. Methanogens like mcrA in low and high N were also reduced by up to 50% from rhizosphere of Ox2 and O8. However, the nitrifying bacterial population such as nosZ reduced in both transgenics significantly, but nirK and nirS did not show a consistent variation. The high yield of transgenic rice with limited aerenchyma mitigates the discharge of CH4 and N2O by reducing root exudates that provide substrates for GHG. Our results improve understanding for breeders to serve the purpose of sustainable development.
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Affiliation(s)
- Muhammad Faseeh Iqbal
- National Key Laboratory of Crop Genetics, Germplasm Enhancement and Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Ministry of Agriculture, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
| | - Yong Zhang
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice Research and Development Center, Nanjing Branch of China National Center for Rice improvement, Nanjing, China
| | - Pulin Kong
- National Key Laboratory of Crop Genetics, Germplasm Enhancement and Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Ministry of Agriculture, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
| | - Yulong Wang
- National Key Laboratory of Crop Genetics, Germplasm Enhancement and Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Ministry of Agriculture, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
| | - Kaixun Cao
- College of Resource and Environment, Anhui Science and Technology University, Chuzhou, China
| | - Limei Zhao
- National Key Laboratory of Crop Genetics, Germplasm Enhancement and Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Ministry of Agriculture, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
| | - Xin Xiao
- College of Resource and Environment, Anhui Science and Technology University, Chuzhou, China
- College of Resource and Environment, Anqing Normal University, Anqing, China
| | - Xiaorong Fan
- National Key Laboratory of Crop Genetics, Germplasm Enhancement and Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Ministry of Agriculture, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- Zhongshan Biological Breeding Laboratory, Nanjing, China
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Ohbayashi T, Wang Y, Aoyagi LN, Hara S, Tago K, Hayatsu M. Diversity of the Hydroxylamine Oxidoreductase (HAO) Gene and Its Enzyme Active Site in Agricultural Field Soils. Microbes Environ 2023; 38:ME23068. [PMID: 38092410 PMCID: PMC10728637 DOI: 10.1264/jsme2.me23068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 10/06/2023] [Indexed: 12/18/2023] Open
Abstract
Nitrification is a key process in the biogeochemical nitrogen cycle and a major emission source of the greenhouse gas nitrous oxide (N2O). The periplasmic enzyme hydroxylamine oxidoreductase (HAO) is involved in the oxidation of hydroxylamine to nitric oxide in the second step of nitrification, producing N2O as a byproduct. Its three-dimensional structure demonstrates that slight differences in HAO active site residues have inhibitor effects. Therefore, a more detailed understanding of the diversity of HAO active site residues in soil microorganisms is important for the development of novel nitrification inhibitors using structure-guided drug design. However, this has not yet been examined. In the present study, we investigated hao gene diversity in beta-proteobacterial ammonia-oxidizing bacteria (β-AOB) and complete ammonia-oxidizing (comammox; Nitrospira spp.) bacteria in agricultural fields using a clone library ana-lysis. A total of 1,949 hao gene sequences revealed that hao gene diversity in β-AOB and comammox bacteria was affected by the fertilizer treatment and field type, respectively. Moreover, hao sequences showed the almost complete conservation of the six HAO active site residues in both β-AOB and comammox bacteria. The diversity of nitrifying bacteria showed similarity between hao and amoA genes. The nxrB amplicon sequence revealed the dominance of Nitrospira cluster II in tea field soils. The present study is the first to reveal hao gene diversity in agricultural soils, which will accelerate the efficient screening of HAO inhibitors and evaluations of their suppressive effects on nitrification in agricultural soils.
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Affiliation(s)
- Tsubasa Ohbayashi
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), 305–8604, Tsukuba, Japan
| | - Yong Wang
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), 305–8604, Tsukuba, Japan
| | - Luciano Nobuhiro Aoyagi
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), 305–8604, Tsukuba, Japan
| | - Shintaro Hara
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), 305–8604, Tsukuba, Japan
| | - Kanako Tago
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), 305–8604, Tsukuba, Japan
| | - Masahito Hayatsu
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), 305–8604, Tsukuba, Japan
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Zhang H, Fang Y, Chen Y, Li Y, Lin Y, Wu J, Cai Y, Chang SX. Enhanced soil potential N 2O emissions by land-use change are linked to AOB-amoA and nirK gene abundances and denitrifying enzyme activity in subtropics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 850:158032. [PMID: 35970464 DOI: 10.1016/j.scitotenv.2022.158032] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 08/10/2022] [Accepted: 08/10/2022] [Indexed: 06/15/2023]
Abstract
Conversion of forestland to intensively managed agricultural land occurs worldwide and can increase soil nitrous oxide (N2O) emissions by altering the transformation processes of nitrogen (N) cycling related microbes and environmental conditions. However, little research has been conducted to assess the relationships between nitrifying and denitrifying functional genes and enzyme activities, the altered soil environment and N2O emissions under forest conversion in subtropical China. Here, we investigated the long-term (two decades) effect of converting natural forests to intensively managed tea (Camellia sinensis L.) plantations on soil potential N2O emissions, inorganic N concentrations, functional gene abundances of nitrifying and denitrifying bacteria, as well as nitrifying and denitrifying enzyme activities in subtropical China. The conversion significantly increased soil potential N2O emissions, which were regulated directly by increased denitrifying enzyme activity (52 %) and nirS + nirK gene abundance (38 %) as shown by structural equation modeling, and indirectly by AOB-amoA gene abundance and inorganic N concentration. Our results indicate that converting natural forests to tea plantations directly increases soil inorganic N concentration, resulting in increases in the abundance of soil nitrifying and denitrifying microorganisms and the associated N2O emissions. These findings are crucial for disentangling the factors that directly and indirectly affect soil potential N2O emissions respond to the conversion of forest to tea plantation.
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Affiliation(s)
- Haikuo Zhang
- State Key Laboratory of Subtropical Silviculture, College of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, China
| | - Yunying Fang
- NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle, NSW 2568, Australia
| | - Youchao Chen
- State Key Laboratory of Subtropical Silviculture, College of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, China
| | - Yong Li
- Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Zhejiang University, Hangzhou 310058, China
| | - Yongxin Lin
- Key Laboratory for Humid Subtropical Eco-geographical Processes of the Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China
| | - Jiasen Wu
- State Key Laboratory of Subtropical Silviculture, College of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, China
| | - Yanjiang Cai
- State Key Laboratory of Subtropical Silviculture, College of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, China.
| | - Scott X Chang
- State Key Laboratory of Subtropical Silviculture, College of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, China; Department of Renewable Resources, University of Alberta, Edmonton T6G 2E3, Canada
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6
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Yao H, Gao X, Guo J, Wang H, Zhang L, Fan L, Jia F, Guo J, Peng Y. Contribution of nitrous oxide to the carbon footprint of full-scale wastewater treatment plants and mitigation strategies- a critical review. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 314:120295. [PMID: 36181929 DOI: 10.1016/j.envpol.2022.120295] [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: 04/12/2022] [Revised: 08/27/2022] [Accepted: 09/24/2022] [Indexed: 06/16/2023]
Abstract
Nitrous oxide (N2O), a potent greenhouse gas, significantly contributes to the carbon footprint of wastewater treatment plants (WWTPs) and contributes significantly to global climate change and to the deterioration of the natural environment. Our understanding of N2O generation mechanisms has significantly improved in the last decade, but the development of effective N2O emission mitigation strategies has lagged owing to the complexity of parameter regulation, substandard monitoring activities, and inadequate policy criteria. Based on critically screened published studies on N2O control in full-scale WWTPs, this review elucidates N2O generation pathway identifications and emission mechanisms and summarizes the impact of N2O on the total carbon footprint of WWTPs. In particular, a linear relationship was established between N2O emission factors and total nitrogen removal efficiencies in WWTPs located in China. Promising N2O mitigation options were proposed, which focus on optimizing operating conditions and implementation of innovative treatment processes. Furthermore, the sustainable operation of WWTPs has been anticipated to convert WWTPs into absolute greenhouse gas reducers as a result of the refinement and improvement of on-site monitoring activities, mitigation mechanisms, regulation of operational parameters, modeling, and policies.
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Affiliation(s)
- Hong Yao
- Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environment, Beijing Jiaotong University, Beijing, 100044, China.
| | - Xinyu Gao
- Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environment, Beijing Jiaotong University, Beijing, 100044, China
| | - Jingbo Guo
- School of Civil Engineering and Architecture, Northeast Electric Power University, Jilin, 132012, China
| | - Hui Wang
- SINOPEC Research Institute of Petroleum Processing, Beijing, 100083, China
| | - Liang Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Liru Fan
- Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environment, Beijing Jiaotong University, Beijing, 100044, China
| | - Fangxu Jia
- Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environment, Beijing Jiaotong University, Beijing, 100044, China
| | - Jianhua Guo
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
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Das S, Wang W, Reeves S, Dalal RC, Dang YP, Gonzalez A, Kopittke PM. Non-target impacts of pesticides on soil N transformations, abundances of nitrifying and denitrifying genes, and nitrous oxide emissions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 844:157043. [PMID: 35779727 DOI: 10.1016/j.scitotenv.2022.157043] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/24/2022] [Accepted: 06/25/2022] [Indexed: 06/15/2023]
Abstract
Agriculture is the leading contributor to global nitrous oxide (N2O) emissions, mostly from soils. We examined the non-target impacts of four pesticides on N transformations, N cycling genes and N2O emissions from sugarcane-cropped soil. The pesticides, including a herbicide glyphosate (GLY), an insecticide imidacloprid (IMI), a fungicide methoxy ethyl mercuric chloride (MEMC) and a fumigant methyl isothiocyanate (MITC), were added to the soil and incubated in laboratory at 25 °C. The soil microcosms were maintained at two water contents, 55 % and 90 % water holding capacity (WHC), to simulate aerobic and partly anaerobic conditions, respectively. Half of the soil samples received an initial application of KNO3 and were then maintained at 90 % WHC for 38 d, whilst the other half received (NH4)2SO4 and were maintained at 55 % WHC for 28 d followed by 10 d at 90 % WHC to favour denitrification. Responses of individual functional genes involved in nitrification and denitrification to the pesticides and their relationships to N2O emissions varied with time and soil water. Overall, MITC had pronounced repressive effects on AOA and AOB amoA gene abundances and gross nitrification. Under 55 % WHC during the initial 28 d, N2O emissions were low for all treatments (≤62 μg N kg-1 soil). However, under 90 % WHC (either during the first 28 d or the increase in water content from 55 to 90 % WHC after 28 d) the cumulative N2O emissions increased markedly. Overall, under 90 % WHC the cumulative N2O emissions were 19 (control) to 79-fold (MITC) higher than under 55% WHC; with the highest emissions observed in the MITC treatment (3140 μg N kg-1 soil). This was associated with increases in gross nitrate consumption rates and abundances of denitrifying genes (nirK, nirS and qnorB). Therefore, to minimise N2O emissions, MITC should not be applied to field under wet conditions favouring denitrification.
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Affiliation(s)
- Shilpi Das
- School of Agriculture and Food Sciences, The University of Queensland, St Lucia, QLD 4072, Australia; Science and Technology Division, Department of Environment and Science, GPO Box 2454, Brisbane, QLD 4001, Australia; Soil Science Division, Bangladesh Institute of Nuclear Agriculture, Mymensingh 2202, Bangladesh.
| | - Weijin Wang
- School of Agriculture and Food Sciences, The University of Queensland, St Lucia, QLD 4072, Australia; Science and Technology Division, Department of Environment and Science, GPO Box 2454, Brisbane, QLD 4001, Australia.
| | - Steven Reeves
- Science and Technology Division, Department of Environment and Science, GPO Box 2454, Brisbane, QLD 4001, Australia
| | - Ram C Dalal
- School of Agriculture and Food Sciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Yash P Dang
- School of Agriculture and Food Sciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Axayacatl Gonzalez
- Australian Institute of Bioengineering and Nanotechnology, St Lucia, QLD 4072, Australia
| | - Peter M Kopittke
- School of Agriculture and Food Sciences, The University of Queensland, St Lucia, QLD 4072, Australia
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Zhou X, Lee J, Yun J, Kim J, Yang Y, Kang H. Distinct Nitrification Rates and Nitrifiers in Needleleaf and Evergreen Broadleaf Forest Soils. MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02110-9. [PMID: 36151339 DOI: 10.1007/s00248-022-02110-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 09/02/2022] [Indexed: 06/16/2023]
Abstract
Research on niche specialization in the microbial communities of ammonia oxidizers is important for assessing the consequences of vegetation shift on nitrogen (N) cycling. In this study, soils were sampled from three tree stands (needleleaf, mixed, and evergreen broadleaf) from the Hannam experimental forest in South Korea in spring (May 2019), summer (August 2019), autumn (November 2019), and winter (January 2020). Quantitative polymerase chain reaction (qPCR) and high-throughput sequencing were used to measure the abundance and community structure of various nitrifiers: ammonia-oxidizing archaea and bacteria (AOA and AOB, respectively) as well as complete ammonia oxidizers (comammox). Nitrification rates and total ammonia oxidizer abundance were significantly higher in needleleaf forest soil than those in other forest stands, and they were lowest in evergreen broadleaf forest soil. Comammox clade B was most abundant in needleleaf and evergreen broadleaf forest soils, while AOA were significantly more abundant in mixed forest soil. The abundances of comammox clade B and AOA were negatively correlated with dissolved organic carbon. Phylogenetic analysis showed that NT-alpha and NS-gamma-2.3.2 were the most abundant AOA lineages in all the samples. The seasonal of AOA, AOB, and comammox varied with the sites, suggesting the need to examine the combinations of environmental factors when considering the effects of seasonal changes in the environment. Overall, the results suggest that potential vegetation shifts in forest ecosystems might affect nitrification activities by regulating the abundance and community structure of ammonia oxidizers.
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Affiliation(s)
- Xue Zhou
- School of Civil and Environmental Engineering, Yonsei University, Seoul, Korea
- College of Agricultural Science and Engineering, Hohai University, Nanjing, China
| | - Jaehyun Lee
- School of Civil and Environmental Engineering, Yonsei University, Seoul, Korea
| | - Jeongeun Yun
- School of Civil and Environmental Engineering, Yonsei University, Seoul, Korea
| | - Jinhyun Kim
- School of Civil and Environmental Engineering, Yonsei University, Seoul, Korea
| | - Yerang Yang
- School of Civil and Environmental Engineering, Yonsei University, Seoul, Korea
| | - Hojeong Kang
- School of Civil and Environmental Engineering, Yonsei University, Seoul, Korea.
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Kabange NR, Lee SM, Shin D, Lee JY, Kwon Y, Kang JW, Cha JK, Park H, Alibu S, Lee JH. Multiple Facets of Nitrogen: From Atmospheric Gas to Indispensable Agricultural Input. Life (Basel) 2022; 12:1272. [PMID: 36013451 PMCID: PMC9410007 DOI: 10.3390/life12081272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/08/2022] [Accepted: 08/16/2022] [Indexed: 11/17/2022] Open
Abstract
Nitrogen (N) is a gas and the fifth most abundant element naturally found in the atmosphere. N's role in agriculture and plant metabolism has been widely investigated for decades, and extensive information regarding this subject is available. However, the advent of sequencing technology and the advances in plant biotechnology, coupled with the growing interest in functional genomics-related studies and the various environmental challenges, have paved novel paths to rediscovering the fundamentals of N and its dynamics in physiological and biological processes, as well as biochemical reactions under both normal and stress conditions. This work provides a comprehensive review on multiple facets of N and N-containing compounds in plants disseminated in the literature to better appreciate N in its multiple dimensions. Here, some of the ancient but fundamental aspects of N are revived and the advances in our understanding of N in the metabolism of plants is portrayed. It is established that N is indispensable for achieving high plant productivity and fitness. However, the use of N-rich fertilizers in relatively higher amounts negatively affects the environment. Therefore, a paradigm shift is important to shape to the future use of N-rich fertilizers in crop production and their contribution to the current global greenhouse gases (GHGs) budget would help tackle current global environmental challenges toward a sustainable agriculture.
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Affiliation(s)
- Nkulu Rolly Kabange
- Department of Southern Area Crop Science, National Institute of Crop Science, RDA, Miryang 50424, Korea
| | - So-Myeong Lee
- Department of Southern Area Crop Science, National Institute of Crop Science, RDA, Miryang 50424, Korea
| | - Dongjin Shin
- Department of Southern Area Crop Science, National Institute of Crop Science, RDA, Miryang 50424, Korea
| | - Ji-Yoon Lee
- Department of Southern Area Crop Science, National Institute of Crop Science, RDA, Miryang 50424, Korea
| | - Youngho Kwon
- Department of Southern Area Crop Science, National Institute of Crop Science, RDA, Miryang 50424, Korea
| | - Ju-Won Kang
- Department of Southern Area Crop Science, National Institute of Crop Science, RDA, Miryang 50424, Korea
| | - Jin-Kyung Cha
- Department of Southern Area Crop Science, National Institute of Crop Science, RDA, Miryang 50424, Korea
| | - Hyeonjin Park
- Department of Southern Area Crop Science, National Institute of Crop Science, RDA, Miryang 50424, Korea
| | - Simon Alibu
- National Crops Resources Research Institute (NaCRRI), NARO, Entebbe 7084, Uganda
| | - Jong-Hee Lee
- Department of Southern Area Crop Science, National Institute of Crop Science, RDA, Miryang 50424, Korea
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10
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Luo L, Ran L, Rasool QZ, Cohan DS. Integrated Modeling of U.S. Agricultural Soil Emissions of Reactive Nitrogen and Associated Impacts on Air Pollution, Health, and Climate. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:9265-9276. [PMID: 35712939 DOI: 10.1021/acs.est.1c08660] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Agricultural soils are leading sources of reactive nitrogen (Nr) species including nitrogen oxides (NOx), ammonia (NH3), and nitrous oxide (N2O). The propensity of NOx and NH3 to generate ozone and fine particulate matter and associated impacts on health are highly variable, whereas the climate impacts of long-lived N2O are independent of emission timing and location. However, these impacts have rarely been compared on a spatially resolved monetized basis. In this study, we update the nitrogen scheme in an agroecosystem model to simulate the Nr emissions from fertilized soils across the contiguous United States. We then apply a reduced-form air pollution health effect model to assess air quality impacts from NOx and NH3 and a social cost of N2O to assess the climate impacts. Assuming an $8.2 million value of a statistical life and a $13,100/ton social cost of N2O, the air quality impacts are a factor of ∼7 to 15 times as large as the climate impacts in heavily populated coastal regions, whereas the ratios are closer to 2.5 in sparsely populated regions. Our results show that air pollution, health, and climate should be considered jointly in future assessments of how farming practices affect Nr emissions.
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Affiliation(s)
- Lina Luo
- Department of Civil and Environmental Engineering, Rice University, Houston, Texas 77005, United States
| | - Limei Ran
- Nature Resources Conservation Service, United States Department of Agriculture, Greensboro, North Carolina 27401, United States
| | - Quazi Z Rasool
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Daniel S Cohan
- Department of Civil and Environmental Engineering, Rice University, Houston, Texas 77005, United States
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11
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Effects of Rainfall on the Characteristics of Soil Greenhouse Gas Emissions in the Wetland of Qinghai Lake. ATMOSPHERE 2022. [DOI: 10.3390/atmos13010129] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Niaodao, a lakeside wetland, was used as the focus of this study to investigate the effect of rainfall changes on the greenhouse gas fluxes of wetland ecosystems. Wetland plots with different moisture characteristics (+25%, −25%, +75%, and −75% rainfall treatments and the control treatment (CK)) were constructed to observe in situ field greenhouse gas emissions at 11:00 and 15:00 (when the daily mean values were similar) in the growing season from May to August 2020 by static chamber–gas chromatography and to investigate the responses of wetland greenhouse gases to different rainfall treatments. The results showed the following: (1) The carbon dioxide (CO2) flux ranged from −49.409 to 374.548 mg·m−2·h−1. The mean CO2 emission flux was greater at 11:00 than at 15:00, and the +25% and +75% treatments exhibited substantially higher CO2 emissions. In addition, the CO2 flux showed a small peak at the beginning of the growing season when the temperature first started to rise. All treatments showed the effect of the CO2 source, and their effects were significantly different. (2) The methane (CH4) flux ranged from −213.839 to 330.976 µg·m−2·h−1 and exhibited an absorption state at 11:00 and an emission state at 15:00. The CH4 emission flux in August (the peak growing season) differed greatly between treatments and was significantly negatively correlated with the rainfall amount (p < 0.05). (3) The nitrous oxide (N2O) flux ranged from −10.457 to 16.878 µg·m−2·h−1 and exhibited a weak source effect throughout the growing season, but it was not significantly correlated with soil moisture; it was, however, negatively correlated with soil temperature. (4) The different treatments resulted in significant differences in soil physical and chemical properties (electrical conductivity, pH, total soil carbon, and total soil nitrogen). The rainfall enhancement treatments significantly improved soil physical and chemical properties.
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12
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Hu J, Richwine JD, Keyser PD, Li L, Yao F, Jagadamma S, DeBruyn JM. Ammonia-oxidizing bacterial communities are affected by nitrogen fertilization and grass species in native C 4 grassland soils. PeerJ 2022; 9:e12592. [PMID: 35003922 PMCID: PMC8684740 DOI: 10.7717/peerj.12592] [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: 09/14/2021] [Accepted: 11/12/2021] [Indexed: 11/20/2022] Open
Abstract
Background Fertilizer addition can contribute to nitrogen (N) losses from soil by affecting microbial populations responsible for nitrification. However, the effects of N fertilization on ammonia oxidizing bacteria under C4 perennial grasses in nutrient-poor grasslands are not well studied. Methods In this study, a field experiment was used to assess the effects of N fertilization rate (0, 67, and 202 kg N ha−1) and grass species (switchgrass (Panicum virgatum) and big bluestem (Andropogon gerardii)) on ammonia-oxidizing bacterial (AOB) communities in C4 grassland soils using quantitative PCR, quantitative reverse transcription-PCR, and high-throughput amplicon sequencing of amoA genes. Results Nitrosospira were dominant AOB in the C4 grassland soil throughout the growing season. N fertilization rate had a stronger influence on AOB community composition than C4 grass species. Elevated N fertilizer application increased the abundance, activity, and alpha-diversity of AOB communities as well as nitrification potential, nitrous oxide (N2O) emission and soil acidity. The abundance and species richness of AOB were higher under switchgrass compared to big bluestem. Soil pH, nitrate, nitrification potential, and N2O emission were significantly related to the variability in AOB community structures (p < 0.05).
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Affiliation(s)
- Jialin Hu
- Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN, United States of America
| | - Jonathan D Richwine
- Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN, United States of America
| | - Patrick D Keyser
- Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN, United States of America
| | - Lidong Li
- Agroecosystem Management Research Unit, USDA-Agricultural Research Service, Lincoln, NE, United States of America
| | - Fei Yao
- Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN, United States of America
| | - Sindhu Jagadamma
- Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN, United States of America
| | - Jennifer M DeBruyn
- Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN, United States of America
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13
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Li Z, Zhang Q, Qiao Y, Leng P, Zhang Q, Du K, Tian C, Li X, Chen G, Li F. Influence of the shallow groundwater table on the groundwater N 2O and direct N 2O emissions in summer maize field in the North China Plain. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 799:149495. [PMID: 34371394 DOI: 10.1016/j.scitotenv.2021.149495] [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: 05/27/2021] [Revised: 07/09/2021] [Accepted: 08/02/2021] [Indexed: 06/13/2023]
Abstract
Agriculture is an important N2O emissions source. Water cycle and nitrogen cycles have important effects on N2O in farmland ecosystems. The changes in the groundwater table can lead to changes in farmland the water and nitrogen cycle processes. However, how this such changes will affect N2O emissions from farmland remains unclear. In this study, a two-year volume lysimeter experiment (2019-2020), including four controlled groundwater tables (i.e., 40, 70, 110, and 150 cm), was performed to monitor the variations in the NO3- and N2O concentrations in shallow groundwater as well as the direct N2O emissions due to surface soil and groundwater evaporation. Our results showed that N2O emissions during fertilization accounted for 80%-90% of the total N2O emissions throughout the maize growing period. Direct N2O emissions increase with the increase in the groundwater table. The total N2O emissions in 2020 were 96.44, 9.75, 6.46, and 6.22 kg ha-1 y-1 at a groundwater table of 40, 70, 110, and 150 cm, respectively. The high water-filled pore space (WFPS) value resulting from the elevated groundwater table increased the groundwater-atmosphere connectivity, leading to significantly increased N2O emissions after fertilization. Increased precipitation (454.90 mm in 2020 vs. 180.30 mm in 2019) accelerated the hydrological processes in agroecology, reducing the retention time of N2O (6 weeks in 2020 vs. 7.5 weeks in 2019) and NO3- (6.75 weeks in 2020 vs. 7.25 weeks in 2019) in shallow groundwater. Studying the influence of shallow groundwater tables on direct N2O emissions will provide insights into the interaction between the water and nitrogen cycles in agroecosystems. The results of this study suggest that direct N2O emissions can be effectively reduced by controlling the groundwater table in agricultural fields in the North China Plain.
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Affiliation(s)
- Zhao Li
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Qiuying Zhang
- Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yunfeng Qiao
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Peifang Leng
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Qian Zhang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Kun Du
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Chao Tian
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaoyan Li
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China
| | - Gang Chen
- Department of Civil and Environmental Engineering, Florida A&M University (FAMU)-Florida State University (FSU) Joint College of Engineering, Tallahassee, FL 32310, United States of America
| | - Fadong Li
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China.
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14
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Wang X, Bai J, Xie T, Wang W, Zhang G, Yin S, Wang D. Effects of biological nitrification inhibitors on nitrogen use efficiency and greenhouse gas emissions in agricultural soils: A review. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 220:112338. [PMID: 34015632 DOI: 10.1016/j.ecoenv.2021.112338] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 04/26/2021] [Accepted: 05/10/2021] [Indexed: 05/27/2023]
Abstract
To maintain and increase crop yields, large amounts of nitrogen fertilizers have been applied to farmland. However, the nitrogen use efficiency (NUE) of chemical fertilizer remains very low, which may lead to serious environmental problems, including nitrate pollution, air quality degradation and greenhouse gas (GHG) emissions. Nitrification inhibitors can alleviate nitrogen loss by inhibiting nitrification; thus, biological nitrification inhibition by plants has gradually attracted increasing attention due to its low cost and environmental friendliness. Research progress on BNI is reviewed in this article, including the source, mechanisms, influencing factors and application of BNIs. In addition, the impact of BNI on agriculture and GHG emissions is summarized from the perspective of agricultural production and environmental protection, and the key future research prospects of BNIs are also noted.
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Affiliation(s)
- Xin Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Junhong Bai
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
| | - Tian Xie
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Wei Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Guangliang Zhang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Shuo Yin
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Dawei Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
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15
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Han P, Wu D, Sun D, Zhao M, Wang M, Wen T, Zhang J, Hou L, Liu M, Klümper U, Zheng Y, Dong HP, Liang X, Yin G. N 2O and NO y production by the comammox bacterium Nitrospira inopinata in comparison with canonical ammonia oxidizers. WATER RESEARCH 2021; 190:116728. [PMID: 33326897 DOI: 10.1016/j.watres.2020.116728] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Revised: 12/01/2020] [Accepted: 12/02/2020] [Indexed: 06/12/2023]
Abstract
Nitrous oxide (N2O) and NOy (nitrous acid (HONO) + nitric oxide (NO) + nitrogen dioxide (NO2)) are released as byproducts or obligate intermediates during aerobic ammonia oxidation, and further influence global warming and atmospheric chemistry. The ammonia oxidation process is catalyzed by groups of globally distributed ammonia-oxidizing microorganisms, which are playing a major role in atmospheric N2O and NOy emissions. Yet, little is known about HONO and NO2 production by the recently discovered, widely distributed complete ammonia oxidizers (comammox), able to individually perform the oxidation of ammonia to nitrate via nitrite. Here, we examined the N2O and NOy production patterns by comammox bacterium Nitrospira inopinata during aerobic ammonia oxidation, in comparison to its canonical ammonia-converting counterparts, representatives of the ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB). Our findings, i) show low yield NOy production by the comammox bacterium compared to AOB; ii) highlight the role of the NO reductase in the biological formation of N2O based on results from NH2OH inhibition assays and its stimulation during archaeal and bacterial ammonia oxidations; iii) postulate that the lack of hydroxylamine (NH2OH) and NO transformation enzymatic activities may lead to a buildup of NH2OH/NO which can abiotically react to N2O ; iv) collectively confirm restrained N2O and NOy emission by comammox bacteria, an unneglectable consortium of microbes in global atmospheric emission of reactive nitrogen gases.
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Affiliation(s)
- Ping Han
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China; State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China; Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China.
| | - Dianming Wu
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China; Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Dongyao Sun
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Mengyue Zhao
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Mengdi Wang
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Teng Wen
- School of Geography, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, China
| | - Jinbo Zhang
- School of Geography, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, China
| | - Lijun Hou
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China; State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China; Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Min Liu
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China; Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Uli Klümper
- Institute for Hydrobiology, Technische Universität Dresden, Dresden, 01062, Germany
| | - Yanling Zheng
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China; State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China; Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Hong-Po Dong
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Xia Liang
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Guoyu Yin
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
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16
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Woodward EE, Edwards TM, Givens CE, Kolpin DW, Hladik ML. Widespread Use of the Nitrification Inhibitor Nitrapyrin: Assessing Benefits and Costs to Agriculture, Ecosystems, and Environmental Health. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:1345-1353. [PMID: 33433195 DOI: 10.1021/acs.est.0c05732] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Agricultural production and associated applications of nitrogen (N) fertilizers have increased dramatically in the last century, and current projections to 2050 show that demands will continue to increase as the human population grows. Applied in both organic and inorganic fertilizer forms, N is an essential nutrient in crop productivity. Increased fertilizer applications, however, create the potential for more N loss before plant uptake. One strategy for minimizing N loss is the use of enhanced efficiency fertilizers, fortified with a nitrification inhibitor, such as nitrapyrin. In soils and water, nitrapyrin inhibits the activity of ammonia monooxygenase, a microbial enzyme that catalyzes the first step of nitrification from ammonium to nitrite. Potential benefits of using nitrification inhibitors range from reduced nitrate leaching and nitrous oxide emissions to increased crop yield. The extent of these benefits, however, depends on environmental conditions and management practices. Thus, such benefits are not always realized. Additionally, nitrapyrin has been shown to transport off-field, and it is unknown what effects environmental nitrapyrin could have on nontarget organisms and the ecological nitrogen cycle. Here, we review the agronomic and environmental benefits and costs of nitrapyrin use and present a series of research questions and considerations to be addressed with future nitrification inhibitor research.
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Affiliation(s)
- Emily E Woodward
- U.S. Geological Survey California Water Science Center, 6000 J Street, Placer Hall, Sacramento, California 95819, United States
| | - Thea M Edwards
- U.S. Geological Survey Columbia Environmental Research Center, 4200 New Haven Road, Columbia, Missouri 65201, United States
| | - Carrie E Givens
- U.S. Geological Survey Upper Midwest Water Science Center, 5840 Enterprise Drive, Lansing, Michigan 48911, United States
| | - Dana W Kolpin
- U.S. Geological Survey Central Midwest Water Science Center, 400 South Clinton Street, Iowa City, Iowa 52240, United States
| | - Michelle L Hladik
- U.S. Geological Survey California Water Science Center, 6000 J Street, Placer Hall, Sacramento, California 95819, United States
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17
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Abstract
Conservation agriculture practices that promote soil health have distinct and lasting effects on microbial populations involved with soil nitrogen (N) cycling. In particular, using a leguminous winter cover crop (hairy vetch) promoted the expression of key functional genes involved in soil N cycling, equaling or exceeding the effects of inorganic N fertilizer. Soil microbial transformations of nitrogen (N) can be affected by soil health management practices. Here, we report in situ seasonal dynamics of the population size (gene copy abundances) and functional activity (transcript copy abundances) of five bacterial genes involved in soil N cycling (ammonia-oxidizing bacteria [AOB] amoA, nifH, nirK, nirS, and nosZ) in a long-term continuous cotton production system under different management practices (cover crops, tillage, and inorganic N fertilization). Hairy vetch (Vicia villosa Roth), a leguminous cover crop, most effectively promoted the expression of N cycle genes, which persisted after cover crop termination throughout the growing season. Moreover, we observed similarly high or even higher N cycle gene transcript abundances under vetch with no fertilizer as no cover crop with N fertilization throughout the cover crop peak and cotton growing seasons (April, May, and October). Further, both the gene and transcript abundances of amoA and nosZ were positively correlated to soil nitrous oxide (N2O) emissions. We also found that the abundances of amoA genes and transcripts both positively correlated to field and incubated net nitrification rates. Together, our results revealed relationships between microbial functional capacity and activity and in situ soil N transformations under different agricultural seasons and soil management practices. IMPORTANCE Conservation agriculture practices that promote soil health have distinct and lasting effects on microbial populations involved with soil nitrogen (N) cycling. In particular, using a leguminous winter cover crop (hairy vetch) promoted the expression of key functional genes involved in soil N cycling, equaling or exceeding the effects of inorganic N fertilizer. Hairy vetch also left a legacy on soil nutrient capacity by promoting the continued activity of N cycling microbes after cover crop termination and into the main growing season. By examining both genes and transcripts involved in soil N cycling, we showed different responses of functional capacity (i.e., gene abundances) and functional activity (i.e., transcript abundances) to agricultural seasons and management practices, adding to our understanding of the effects of soil health management practices on microbial ecology.
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18
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Voegel TM, Larrabee MM, Nelson LM. Development of droplet digital PCR assays to quantify genes involved in nitrification and denitrification, comparison with quantitative real-time PCR and validation of assays in vineyard soil. Can J Microbiol 2020; 67:174-187. [PMID: 32910858 DOI: 10.1139/cjm-2020-0033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Quantifying genes in soil is important to relate the abundance of soil bacteria to biogeochemical cycles. Quantitative real-time PCR is widely used for quantification, but its use with environmental samples is limited by poor reaction efficiencies or by PCR inhibition through co-purified soil substances. Droplet digital PCR (ddPCR) is a technology for absolute, sensitive quantification of genes. This study optimized eight ddPCR assays to quantify total bacteria and archaea as well as the nitrification (bacterial and archaeal amoA) and denitrification (nirS, nirK, nosZI, nosZII) genes involved in the generation or reduction of the greenhouse gas nitrous oxide. Detection and quantification thresholds were compared with those of quantitative real-time PCR and were equal to, or improved, in ddPCR. To validate the assays using environmental samples, soil DNA was isolated from two vineyards in the Okanagan valley in British Columbia, Canada, over the 2017 growing season. Soil properties related to the observed gene abundances were determined. Total bacteria, nirK, and nosZII increased with time and the soil C/N ratio and NH4+-N concentration affected total archaea and archaeal amoA negatively. The results, compared with those of other studies, showed that ddPCR is a valid alternative to qPCR to quantify genes involved in nitrification or denitrification.
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Affiliation(s)
- Tanja M Voegel
- Irving K. Barber Faculty of Science, Department of Biology, University of British Columbia Okanagan, 1177 Research Road, Kelowna, BC V1V 1V7, Canada.,Irving K. Barber Faculty of Science, Department of Biology, University of British Columbia Okanagan, 1177 Research Road, Kelowna, BC V1V 1V7, Canada
| | - Melissa M Larrabee
- Irving K. Barber Faculty of Science, Department of Biology, University of British Columbia Okanagan, 1177 Research Road, Kelowna, BC V1V 1V7, Canada.,Irving K. Barber Faculty of Science, Department of Biology, University of British Columbia Okanagan, 1177 Research Road, Kelowna, BC V1V 1V7, Canada
| | - Louise M Nelson
- Irving K. Barber Faculty of Science, Department of Biology, University of British Columbia Okanagan, 1177 Research Road, Kelowna, BC V1V 1V7, Canada.,Irving K. Barber Faculty of Science, Department of Biology, University of British Columbia Okanagan, 1177 Research Road, Kelowna, BC V1V 1V7, Canada
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19
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Villegas D, Arevalo A, Nuñez J, Mazabel J, Subbarao G, Rao I, De Vega J, Arango J. Biological Nitrification Inhibition (BNI): Phenotyping of a Core Germplasm Collection of the Tropical Forage Grass Megathyrsus maximus Under Greenhouse Conditions. FRONTIERS IN PLANT SCIENCE 2020; 11:820. [PMID: 32595688 PMCID: PMC7304326 DOI: 10.3389/fpls.2020.00820] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 05/22/2020] [Indexed: 05/31/2023]
Abstract
Modern intensively managed pastures that receive large external nitrogen (N) inputs account for high N losses in form of nitrate (NO3 -) leaching and emissions of the potent greenhouse gas nitrous oxide (N2O). The natural plant capacity to shape the soil N cycle through exudation of organic compounds can be exploited to favor N retention without affecting productivity. In this study, we estimated the relationship between biological nitrification inhibition (BNI), N2O emissions and plant productivity for 119 germplasm accessions of Guineagrass (Megathyrsus maximus), an important tropical forage crop for livestock production. This relation was tested in a greenhouse experiment measuring BNI as (i) rates of soil nitrification; (ii) abundance of ammonia-oxidizing bacteria (AOB) and archaea (AOA); and (iii) the capacity of root tissue extracts to inhibit nitrification in vitro. We then measured N2O emissions, aboveground biomass and forage nutrition quality parameters. Reductions on nitrification activity ranging between 30 and 70% were found across the germplasm collection of M. maximus. Accessions with low nitrification rates showed a lower abundance of AOB as well as a reduction in N2O emissions compared to accessions of high nitrification rates. The BNI capacity was not correlated to N uptake of plants, suggesting that there may be intraspecific variation in the exploitation of different N sources in this grass species. A group of accessions (cluster) with the most desirable agronomic and environmental traits among the collection was identified for further field validation. These results provide evidence of the ability of M. maximus to suppress soil nitrification and N2O emissions and their relationship with productivity and forage quality, pointing a way to develop N conservative improved forage grasses for tropical livestock production.
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Affiliation(s)
- Daniel Villegas
- International Center for Tropical Agriculture (CIAT), Cali, Colombia
| | - Ashly Arevalo
- International Center for Tropical Agriculture (CIAT), Cali, Colombia
| | - Jonathan Nuñez
- International Center for Tropical Agriculture (CIAT), Cali, Colombia
| | - Johanna Mazabel
- International Center for Tropical Agriculture (CIAT), Cali, Colombia
| | - Guntur Subbarao
- Japan International Research Center for Agricultural Sciences (JIRCAS), Tsukuba, Japan
| | - Idupulapati Rao
- International Center for Tropical Agriculture (CIAT), Cali, Colombia
| | - Jose De Vega
- Earlham Institute, Norwich Research Park, Norwich, United Kingdom
| | - Jacobo Arango
- International Center for Tropical Agriculture (CIAT), Cali, Colombia
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Cassman NA, Soares JR, Pijl A, Lourenço KS, van Veen JA, Cantarella H, Kuramae EE. Nitrification inhibitors effectively target N 2 O-producing Nitrosospira spp. in tropical soil. Environ Microbiol 2019; 21:1241-1254. [PMID: 30735001 PMCID: PMC6850170 DOI: 10.1111/1462-2920.14557] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 01/09/2019] [Accepted: 02/04/2019] [Indexed: 01/01/2023]
Abstract
The nitrification inhibitors (NIs) 3,4-dimethylpyrazole (DMPP) and dicyandiamide (DCD) can effectively reduce N2 O emissions; however, which species are targeted and the effect of these NIs on the microbial nitrifier community is still unclear. Here, we identified the ammonia oxidizing bacteria (AOB) species linked to N2 O emissions and evaluated the effects of urea and urea with DCD and DMPP on the nitrifying community in a 258 day field experiment under sugarcane. Using an amoA AOB amplicon sequencing approach and mining a previous dataset of 16S rRNA sequences, we characterized the most likely N2 O-producing AOB as a Nitrosospira spp. and identified Nitrosospira (AOB), Nitrososphaera (archaeal ammonia oxidizer) and Nitrospira (nitrite-oxidizer) as the most abundant, present nitrifiers. The fertilizer treatments had no effect on the alpha and beta diversities of the AOB communities. Interestingly, we found three clusters of co-varying variables with nitrifier operational taxonomic units (OTUs): the N2 O-producing AOB Nitrosospira with N2 O, NO3 - , NH4 + , water-filled pore space (WFPS) and pH; AOA Nitrososphaera with NO3 - , NH4 + and pH; and AOA Nitrososphaera and NOB Nitrospira with NH4 + , which suggests different drivers. These results support the co-occurrence of non-N2 O-producing Nitrososphaera and Nitrospira in the unfertilized soils and the promotion of N2 O-producing Nitrosospira under urea fertilization. Further, we suggest that DMPP is a more effective NI than DCD in tropical soil under sugarcane.
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Affiliation(s)
- Noriko A. Cassman
- Department of Microbial EcologyNetherlands Institute for Ecology NIOO‐KNAWWageningenNetherlands
| | - Johnny R. Soares
- Department of Microbial EcologyNetherlands Institute for Ecology NIOO‐KNAWWageningenNetherlands
- Soil Sciences and Fertility, Soil and Environmental Resources Center, Agronomic Institute of CampinasP.O. Box 28, 13012‐970, CampinasSPBrazil
| | - Agata Pijl
- Department of Microbial EcologyNetherlands Institute for Ecology NIOO‐KNAWWageningenNetherlands
| | - Késia S. Lourenço
- Department of Microbial EcologyNetherlands Institute for Ecology NIOO‐KNAWWageningenNetherlands
- Soil Sciences and Fertility, Soil and Environmental Resources Center, Agronomic Institute of CampinasP.O. Box 28, 13012‐970, CampinasSPBrazil
| | - Johannes A. van Veen
- Department of Microbial EcologyNetherlands Institute for Ecology NIOO‐KNAWWageningenNetherlands
| | - Heitor Cantarella
- Soil Sciences and Fertility, Soil and Environmental Resources Center, Agronomic Institute of CampinasP.O. Box 28, 13012‐970, CampinasSPBrazil
| | - Eiko E. Kuramae
- Department of Microbial EcologyNetherlands Institute for Ecology NIOO‐KNAWWageningenNetherlands
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21
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Guo L, Wang X, Diao T, Ju X, Zheng L, Zhang X, Han X. N 2O emission contributions by different pathways and associated microbial community dynamics in a typical calcareous vegetable soil. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 242:2005-2013. [PMID: 30061078 DOI: 10.1016/j.envpol.2018.07.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 06/18/2018] [Accepted: 07/06/2018] [Indexed: 06/08/2023]
Abstract
Nitrous oxide, one of the powerful long-lived greenhouse gases, is emitted mainly through biological processes, especially from fertilized soil. It is critical to partition the contribution of different pathways to N2O emissions and the relevant characteristics of microbial communities to identify the key N2O processes. An microcosm was conducted to partition the N2O emissions from different pathways, and the changes in soil mineral nitrogen and various nitrifiers (amoA bacteria and amoA archaea) and denitrifiers (nirS, nirK, and nosZ) were also determined using qPCR and high-throughput sequencing methods. Different gas inhibitor combinations (i.e., 0.06% acetylene, pure oxygen, 0.06% acetylene in pure oxygen, and pure helium) were used to partition the N2O pathways. A 5% oxygen treatment, with and without acetylene, was also included so that the N2O emissions could be measured under lower oxygen partial pressure. Results showed that ammonia-oxidation (AO) and successive nitrifier denitrification (NiD) were the main pathways contributing to N2O emissions at the earlier period after ammonium sulfate application with the cumulative N2O emissions accounting for 30.9% and 59.2% of the total N2O emissions, respectively. The higher NiD N2O contributions occurred when the soil nitrite concentration appeared higher, especially under the lower oxygen conditions. Higher N2O emissions from AO and NiD were associated with the compositional proportion of some dominant AOB species. Denitrification contributed more N2O (63.6%-69.3%) in the later period during incubation, coinciding with the following characteristics for denitrifiers: a) lower nosZ/(nirS + nirK) ratio, b) more diversity in nirS, and c) different proportions of some dominant species in nirK. Our results demonstrated that higher AO and successive NiD were the main N2O emission pathways, suggesting that controlling the ammonium content and weakening the AO are critical in decreasing N2O emissions.
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Affiliation(s)
- Liping Guo
- Key Lab for Agro-Environment, Ministry of Agriculture, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Xuedong Wang
- College of Resource Environment and Tourism, Capital Normal University, Beijing, 100048, China
| | - Tiantian Diao
- Key Lab for Agro-Environment, Ministry of Agriculture, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xiaotang Ju
- College of Resources and Environmental Sciences, Key Lab of Plant-Soil Interaction of MOE, China Agricultural University, Beijing 100093, China
| | - Lei Zheng
- Key Lab for Agro-Environment, Ministry of Agriculture, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; College of Resource Environment and Tourism, Capital Normal University, Beijing, 100048, China
| | - Xinyue Zhang
- Key Lab for Agro-Environment, Ministry of Agriculture, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xue Han
- Key Lab for Agro-Environment, Ministry of Agriculture, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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22
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Yoo G, Lee YO, Won TJ, Hyun JG, Ding W. Variable effects of biochar application to soils on nitrification-mediated N 2O emissions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 626:603-611. [PMID: 29358139 DOI: 10.1016/j.scitotenv.2018.01.098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 12/26/2017] [Accepted: 01/10/2018] [Indexed: 06/07/2023]
Abstract
Although a meta-analysis on biochar's effects on N2O emission reported an overall reduction in N2O emission by adding biochar to the soils, there are still variations in the changes in N2O emission, especially from field results. The objectives of this study are 1) to compare the effects of biochar addition on N2O emission between three agricultural upland field experiments, where soil water status was dry favoring nitrification and 2) to identify main factors explaining biochar's variable effects on N2O emission. Three field experiments were conducted: Exp A in the cultivated grassland treated with rice husk biochar at 2 ton ha-1 + urea (CHAR) and with urea only (CON); Exp B in the cabbage field with CHAR and CON treatments; and Exp C in the pepper field with CHAR, CON, and CHAR + DCD (dicyandiamide, nitrification inhibitor) treatments. In Exp A and C, cumulative N2O emissions significantly increased by 82.5% and 55.8% in the CHAR than CON treatments, respectively, while in Exp B, there was no difference in cumulative N2O emission between the CHAR and CON. Based on results from using nitrification inhibitor and soil % water filled pore space (WFPS), we assumed that the main N2O production mechanism was nitrification. Our results suggest that soil water status right after urea application is the primary determinant of different effects of biochar on N2O emission in addition to soil C status and biochar's adsorption. Principal component analysis using the 25 compiled data also supported our results. This study identified the specific field conditions under which biochar could have stimulating effects on N2O emission. Mitigation potential of biochar application should be reconsidered if biochar and urea were amended to dry soils with low C contents.
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Affiliation(s)
- Gayoung Yoo
- Department of Applied Environmental Science, Kyung Hee University, 1732, Deogyeong-daero, Giheung-gu, Yongin-si, Gyeonggi-do 446701, Republic of Korea.
| | - Yong Oon Lee
- Department of Applied Environmental Science, Kyung Hee University, 1732, Deogyeong-daero, Giheung-gu, Yongin-si, Gyeonggi-do 446701, Republic of Korea
| | - Tae Jin Won
- Gyeonggi-do Agricultural Research and Extension Services, 283-33, Byeongjeomjungang-ro, Hwaseong-si, Gyeonggi-do, Republic of Korea
| | - Jun Ge Hyun
- Department of Applied Environmental Science, Kyung Hee University, 1732, Deogyeong-daero, Giheung-gu, Yongin-si, Gyeonggi-do 446701, Republic of Korea
| | - Weixin Ding
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
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Coskun D, Britto DT, Shi W, Kronzucker HJ. How Plant Root Exudates Shape the Nitrogen Cycle. TRENDS IN PLANT SCIENCE 2017; 22:661-673. [PMID: 28601419 DOI: 10.1016/j.tplants.2017.05.004] [Citation(s) in RCA: 162] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 05/08/2017] [Accepted: 05/10/2017] [Indexed: 05/23/2023]
Abstract
Although the global nitrogen (N) cycle is largely driven by soil microbes, plant root exudates can profoundly modify soil microbial communities and influence their N transformations. A detailed understanding is now beginning to emerge regarding the control that root exudates exert over two major soil N processes - nitrification and N2 fixation. We discuss recent breakthroughs in this area, including the identification of root exudates as nitrification inhibitors and as signaling compounds facilitating N-acquisition symbioses. We indicate gaps in current knowledge, including questions of how root exudates affect newly discovered microbial players and N-cycle components. A better understanding of these processes is urgent given the widespread inefficiencies in agricultural N use and their links to N pollution and climate change.
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Affiliation(s)
- Devrim Coskun
- Department of Biological Sciences and Canadian Centre for World Hunger Research (CCWHR), University of Toronto, Toronto M1C 1A4, ON, Canada; Département de Phytologie, Faculté des Sciences de l'Agriculture et de l'Alimentation (FSAA), Université Laval, Québec G1V 0A6, QC, Canada
| | - Dev T Britto
- Department of Biological Sciences and Canadian Centre for World Hunger Research (CCWHR), University of Toronto, Toronto M1C 1A4, ON, Canada
| | - Weiming Shi
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Herbert J Kronzucker
- Department of Biological Sciences and Canadian Centre for World Hunger Research (CCWHR), University of Toronto, Toronto M1C 1A4, ON, Canada; School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia.
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24
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Coskun D, Britto DT, Shi W, Kronzucker HJ. Nitrogen transformations in modern agriculture and the role of biological nitrification inhibition. NATURE PLANTS 2017; 3:17074. [PMID: 28585561 DOI: 10.1038/nplants.2017.74] [Citation(s) in RCA: 157] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 04/25/2017] [Indexed: 05/20/2023]
Abstract
The nitrogen (N)-use efficiency of agricultural plants is notoriously poor. Globally, about 50% of the N fertilizer applied to cropping systems is not absorbed by plants, but lost to the environment as ammonia (NH3), nitrate (NO3-), and nitrous oxide (N2O, a greenhouse gas with 300 times the heat-trapping capacity of carbon dioxide), raising agricultural production costs and contributing to pollution and climate change. These losses are driven by volatilization of NH3 and by a matrix of nitrification and denitrification reactions catalysed by soil microorganisms (chiefly bacteria and archaea). Here, we discuss mitigation of the harmful and wasteful process of agricultural N loss via biological nitrification inhibitors (BNIs) exuded by plant roots. We examine key recent discoveries in the emerging field of BNI research, focusing on BNI compounds and their specificity and transport, and discuss prospects for their role in improving agriculture while reducing its environmental impact.
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Affiliation(s)
- Devrim Coskun
- Department of Biological Sciences and Canadian Centre for World Hunger Research (CCWHR), University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Dev T Britto
- Department of Biological Sciences and Canadian Centre for World Hunger Research (CCWHR), University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Weiming Shi
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Herbert J Kronzucker
- Department of Biological Sciences and Canadian Centre for World Hunger Research (CCWHR), University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
- School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia
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