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Gong JC, Li BH, Liu CY, Li QD, Hu JW, Li PF, He D, Yang GP. Nitrogen oxides emissions from coastal wetland sediments: Experimental assessment of the influence of vegetation and nitrogen input. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 954:176660. [PMID: 39362540 DOI: 10.1016/j.scitotenv.2024.176660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2024] [Revised: 09/30/2024] [Accepted: 09/30/2024] [Indexed: 10/05/2024]
Abstract
Nitrogen oxides (NOx = NO + NO2) have essential impacts on global climate and the environment, making it essential to study the contribution of wetland-generated NOx to environmental problems. With exogenous nitrogen input from anthropogenic activities, wetland sediments become active emission hotspots for NOx. In this study, we conducted field experiments in a typical salt marsh wetland to measure nitric oxide (NO, the primary component of NOx from sediments) exchange fluxes in both mudflat and vegetated sediments. We found that NO fluxes in vegetated sediments (0.40 ± 0.15 × 10-12 kg N m-2 s-1) were relatively higher than in mudflat sediments (-1.31 ± 1.39 × 10-12 kg N m-2 s-1), with this difference occurring only during the vegetation-dying season (autumn). Correlations between sediment NO fluxes and environmental parameters revealed that NO flux variation during the observation period was primarily influenced by sediment respiration, temperature, water content, and substrate availability. However, the influence of these factors on NO fluxes differed between mudflat and vegetated sediments. In-situ data analysis also suggested that tidal horizontal migration, which affects sediment substrate and salinity, may regulate sediment NO emissions. Furthermore, in-situ incubations with nitrogen addition (ammonia, nitrite, and nitrate) were conducted to study the response of sediment NO emissions to exogenous nitrogen. We observed that nitrogen addition caused a 259.7 % increase in NO emissions from vegetated sediments compared to the control during the effective period of nitrogen addition (days 1-3). However, although nitrogen addition markedly stimulated sediment NO emissions, the overall NO production capacity constrained the extent of this increase.
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Affiliation(s)
- Jiang-Chen Gong
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao Marine Science and Technology Center, Qingdao 266237, China
| | - Bing-Han Li
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao Marine Science and Technology Center, Qingdao 266237, China
| | - Chun-Ying Liu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao Marine Science and Technology Center, Qingdao 266237, China.
| | - Qin-Dao Li
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao Marine Science and Technology Center, Qingdao 266237, China
| | - Jing-Wen Hu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
| | - Pei-Feng Li
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
| | - Dan He
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
| | - Gui-Peng Yang
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao Marine Science and Technology Center, Qingdao 266237, China
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Wang Y, Sha Y, Ren Z, Huang Y, Gao Q, Wang S, Li X, Feng G. Conservative strip tillage system in maize maintains high yield and mitigates GHG emissions but promotes N 2O emissions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 932:173067. [PMID: 38723964 DOI: 10.1016/j.scitotenv.2024.173067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 04/09/2024] [Accepted: 05/06/2024] [Indexed: 05/12/2024]
Abstract
Optimizing N application under straw-covered strip tillage is of great significance to the rational utilization of stover resources as well as ensure food and ecosystem security, and especially N2O emissions from agricultural systems. Quantifying N2O emissions and even the carbon footprint (CF) from agricultural systems is crucial for future protecting agricultural production systems. A two-year field experiment was conducted on black soil in Northeast China, which set up two tillage systems: strip tillage with straw returning (ST) and conventional tillage (control: CT) without straw and three nitrogen rates: 0, farmers' practice (Nfp 240 kg hm-2), and optimized nitrogen fertilizer (Nopt 180 kg hm-2). We examined the characteristics of N2O emissions and CF under the ST and CT systems. Among them, we indirectly calculated GHG emissions using the LCA method. Compared with CT, the ST system significantly reduces indirect GHG emissions, but did significantly increase direct cumulative N2O emissions by 20.7 %, most likely because the higher soil residual nitrate nitrogen content, WFPS, and soil temperature under ST was 13.0 %, 2 % and 5.7 % higher than that under CT. Nopt treatment markedly reduced cumulative N2O emissions by 36.0 %, CFarea, CFyield, and CFNPV by 22.4 %, 23.1 %, and 23.5 % in ST, respectively, compared to Nfp. The reduction in energy use of machinery in ST results in lower fuel consumption and thus generating less CF. What's more, the decrease of CFyield and CFNPV between nitrogen application treatments under ST was 5.2 % and 7.7 % higher than CT, respectively. ST system can effectively achieve higher grain yield and mitigate GHG emissions on black soil in Northeast China compared with CT, but attention should be paid to N2O emissions in the soil during the maize growth period. The sustainability of balancing GHG emissions, and economic and environmental benefits can be achieved by optimizing nitrogen fertilizer manage.
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Affiliation(s)
- Yingmiao Wang
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Key Laboratory of Sustainable Utilization of Soil Resources in the Commodity Grain Bases in Jilin Province, College of Resources and Environmental Sciences, Jilin Agricultural University, Changchun 130118, Jilin, China
| | - Ye Sha
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Zizi Ren
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Key Laboratory of Sustainable Utilization of Soil Resources in the Commodity Grain Bases in Jilin Province, College of Resources and Environmental Sciences, Jilin Agricultural University, Changchun 130118, Jilin, China
| | - Yiwen Huang
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Qiang Gao
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Key Laboratory of Sustainable Utilization of Soil Resources in the Commodity Grain Bases in Jilin Province, College of Resources and Environmental Sciences, Jilin Agricultural University, Changchun 130118, Jilin, China
| | - Shaojie Wang
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Key Laboratory of Sustainable Utilization of Soil Resources in the Commodity Grain Bases in Jilin Province, College of Resources and Environmental Sciences, Jilin Agricultural University, Changchun 130118, Jilin, China
| | - Xiaoyu Li
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Key Laboratory of Sustainable Utilization of Soil Resources in the Commodity Grain Bases in Jilin Province, College of Resources and Environmental Sciences, Jilin Agricultural University, Changchun 130118, Jilin, China.
| | - Guozhong Feng
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Ministry of Education, Key Laboratory of Sustainable Utilization of Soil Resources in the Commodity Grain Bases in Jilin Province, College of Resources and Environmental Sciences, Jilin Agricultural University, Changchun 130118, Jilin, China.
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Dlamini JC, Tesfamariam EH, Verbeeck M, Loick N, Louro‐Lopez A, Hawkins JMB, Blackwell MSA, Dunn RM, Collins AL, Cardenas LM. Do NO, N 2O, N 2 and CO 2 fluxes differ in soils sourced from cropland and varying riparian buffer vegetation? An incubation study. SOIL USE AND MANAGEMENT 2024; 40:e12951. [PMID: 38516181 PMCID: PMC10952594 DOI: 10.1111/sum.12951] [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: 02/22/2023] [Revised: 07/21/2023] [Accepted: 07/22/2023] [Indexed: 03/23/2024]
Abstract
Riparian buffers are expedient interventions for water quality functions in agricultural landscapes. However, the choice of vegetation and management affects soil microbial communities, which in turn affect nutrient cycling and the production and emission of gases such as nitric oxide (NO), nitrous oxide (N2O), nitrogen gas (N2) and carbon dioxide (CO2). To investigate the potential fluxes of the above-mentioned gases, soil samples were collected from a cropland and downslope grass, willow and woodland riparian buffers from a replicated plot scale experimental facility. The soils were re-packed into cores and to investigate their potential to produce the aforementioned gases via potential denitrification, a potassium nitrate (KNO3 -) and glucose (labile carbon)-containing amendment, was added prior to incubation in a specialized laboratory DENItrification System (DENIS). The resulting NO, N2O, N2 and CO2 emissions were measured simultaneously, with the most NO (2.9 ± 0.31 mg NO m-2) and N2O (1413.4 ± 448.3 mg N2O m-2) generated by the grass riparian buffer and the most N2 (698.1 ± 270.3 mg N2 m-2) and CO2 (27,558.3 ± 128.9 mg CO2 m-2) produced by the willow riparian buffer. Thus, the results show that grass riparian buffer soils have a greater NO3 - removal capacity, evidenced by their large potential denitrification rates, while the willow riparian buffers may be an effective riparian buffer as its soils potentially promote complete denitrification to N2, especially in areas with similar conditions to the current study.
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Affiliation(s)
- J. C. Dlamini
- Department of Soil, Crop and Climate SciencesUniversity of the Free StateBloemfonteinSouth Africa
- Sustainable Agriculture Sciences, Rothamsted ResearchOkehamptonUK
- Department of Plant and Soil SciencesUniversity of PretoriaHatfieldSouth Africa
| | - E. H. Tesfamariam
- Department of Plant and Soil SciencesUniversity of PretoriaHatfieldSouth Africa
| | - M. Verbeeck
- Sustainable Agriculture Sciences, Rothamsted ResearchOkehamptonUK
| | - N. Loick
- Sustainable Agriculture Sciences, Rothamsted ResearchOkehamptonUK
| | - A. Louro‐Lopez
- Sustainable Agriculture Sciences, Rothamsted ResearchOkehamptonUK
| | - J. M. B. Hawkins
- Sustainable Agriculture Sciences, Rothamsted ResearchOkehamptonUK
| | | | - R. M. Dunn
- Sustainable Agriculture Sciences, Rothamsted ResearchOkehamptonUK
| | - A. L. Collins
- Sustainable Agriculture Sciences, Rothamsted ResearchOkehamptonUK
| | - L. M. Cardenas
- Sustainable Agriculture Sciences, Rothamsted ResearchOkehamptonUK
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Gong JC, Li BH, Hu JW, Li PF, Liu Q, Yang GP, Liu CY. Driving force of tidal pulses on denitrifiers-dominated nitrogen oxide emissions from intertidal wetland sediments. WATER RESEARCH 2023; 247:120770. [PMID: 37897991 DOI: 10.1016/j.watres.2023.120770] [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: 05/19/2023] [Revised: 09/12/2023] [Accepted: 10/20/2023] [Indexed: 10/30/2023]
Abstract
Intertidal wetland sediments are an important source of atmospheric nitrogen oxides (NOx), but their contribution to the global NOx budget remains unclear. In this work, we conducted year-round and diurnal observations in the intertidal wetland of Jiaozhou Bay to explore their regional source-sink patterns and influence factors on NOx emissions (initially in the form of nitric oxide) and used a dynamic soil reactor to further extend the mechanisms underlying the tidal pulse of nitric oxide (NO) observed in our investigations. The annual fluxes of NOx in the vegetated wetland were significantly higher than those in the wetland without vegetation. Their annual variations could be attributed to changes in temperature and the amount of organic carbon in the sediment, which was derived from vegetated plants and promoted the carbon-nitrogen cycle. Anaerobic denitrifiers had advantages in the intertidal wetland sediment and accounted for the major NO production (63.8 %) but were still limited by nitrite and nitrate concentrations in the sediment. Moreover, the tidal pulse was likely a primary driver of NOx emissions from intertidal wetlands over short periods, which was not considered in previous investigations. The annual NO exchange flux considering the tide pulse contribution (8.93 ± 1.72 × 10-2 kg N ha-1 yr-1) was significantly higher than that of the non-pulse period (4.14 ± 1.13 × 10-2 kg N ha-1 yr-1) in our modeling result for the fluxes over the last decade. Therefore, the current measurement of NOx fluxes underestimated the actual gas emission without considering the tidal pulse.
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Affiliation(s)
- Jiang-Chen Gong
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Bing-Han Li
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Jing-Wen Hu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
| | - Pei-Feng Li
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
| | - Qian Liu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
| | - Gui-Peng Yang
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China.
| | - Chun-Ying Liu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China.
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5
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Petrasek MR, Piñeiro G, Bonvecchi VE, Yahdjian L. Are service crops an alternative for mitigating N 2 O emissions in soybean crops in the Argentinian Pampas? JOURNAL OF ENVIRONMENTAL QUALITY 2023; 52:258-269. [PMID: 36493465 DOI: 10.1002/jeq2.20445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
Service crops (or cover crops) play an important role in simplified agricultural systems. Service crops reduce agricultural external inputs and increase ecosystem services but their ability to mitigate nitrous oxide (N2 O) emissions is still uncertain. The main objective of this study was to evaluate N2 O emissions in soybean-soybean (Glycine max [L.] Merr) rotations that included different service crops. Treatments included continuous soybean with winter fallow and soybean with three service crops: oat (Avena sativa L.), vetch (Vicia villosa Roth.), and a mixture of oat and vetch in a randomized complete block design. Service crops were sown 2 months after soybean harvest and were terminated 2 months before soybean planting. Nitrous oxide emissions were determined during the fourth year of the field experiment. We found that service crops did not significantly affect overall mean N2 O emission rates, with mean emission rates from the fallow, oat, vetch, and oat-vetch treatments of 1.82 ± 0.35, 1.95 ± 0.34, 2.71 ± 0.43, and 2.42 ± 0.42 kg N2 O-N ha-1 per year, respectively. Service crops with low C/N ratios (vetch and oat-vetch mixtures) significantly increased N2 O emissions in spring, after their termination. Overall, soil inorganic N content (NO3 - or NH4 + ) was the main driver that explained the N2 O emissions from different treatments, whereas water-filled pore space controlled the temporal variability of emissions. Our results suggest that service crops with a very short growing season may increase soil N availability for cash crops, but do not reduce N2 O emissions due to long periods of high N availability without crops.
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Affiliation(s)
- Marcos René Petrasek
- Departamento de Tecnología, Edafología, Universidad Nacional de Luján, Buenos Aires, Argentina
| | - Gervasio Piñeiro
- Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
- Cátedra de Ecología, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
| | | | - Laura Yahdjian
- Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
- Cátedra de Ecología, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
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Cui P, Chen Z, Fan F, Yin C, Song A, Li T, Zhang H, Liang Y. Soil texture is an easily overlooked factor affecting the temperature sensitivity of N 2O emissions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 862:160648. [PMID: 36502980 DOI: 10.1016/j.scitotenv.2022.160648] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/25/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
As a potent greenhouse gas, soil nitrous oxide (N2O) is strongly stimulated by rising temperature, triggering a positive feedback effect of global warming. However, its temperature sensitivity varies greatly among soils with different physical and chemical characteristics, while associated mechanisms remain unknown. Here we performed a meta-analysis of the effect of warming on N2O emission and found distinctions in the response of N2O to temperature increase in soils with different textures. Then, we conducted an incubation experiment on 11 arable soils with varying textures sampled across China. The results show that the temperature sensitivity of N2O emissions was lower as soil texture became more clayey and was consistent with the outcome of meta-analysis. Further analysis was conducted by classifying the soils into clay and loam subgroups. As shown in the clay soil subgroup, N2O emission was significantly correlated with both inorganic nitrogen contents and potential denitrification and nitrification activities. Correlation analysis and partial least square (PLS) path model revealed that temperature mediated N2O emission by regulating nosZ gene abundance indirectly. In loam soils, however, the indirect effect of temperature on N2O production was achieved mainly through nirS gene abundance. Additionally, soil DON content strongly correlated with N2O emission in both subgroups and affected N2O emissions by influencing the abundance of denitrifiers under warming conditions. Our findings suggest that (i) soil texture was an important factor affecting temperature sensitivity of N2O emission and (ii) variable efficacy of warming in soil N2O production might originate from the enriching DON and nitrate content and its different indirect effects on nirS- or nosZ-type denitrifiers.
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Affiliation(s)
- Peiyuan Cui
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of crop cultivation and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China; Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Zhixuan Chen
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of crop cultivation and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Fenliang Fan
- Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Chang Yin
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China; Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Alin Song
- Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Tingqiang Li
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hongcheng Zhang
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of crop cultivation and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Yongchao Liang
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China.
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Berendt J, Jurasinski G, Wrage-Mönnig N. Influence of rewetting on N 2O emissions in three different fen types. NUTRIENT CYCLING IN AGROECOSYSTEMS 2022; 125:277-293. [PMID: 36373007 PMCID: PMC9638291 DOI: 10.1007/s10705-022-10244-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 10/21/2022] [Indexed: 06/16/2023]
Abstract
UNLABELLED In recent years, many peatlands in Europe have been rewetted for nature conservation and global warming mitigation. However, the effects on emissions of the greenhouse gas nitrous oxide (N2O) have been found to be highly variable and driving factors are poorly understood. Therefore, we measured N2O fluxes every two weeks over three years on pairs of sites (one drained, one rewetted) of three important peatland types in North-Eastern Germany, namely, percolation fen, alder forest and coastal fen. Additionally, every three months, sources of N2O were determined using a stable isotope mapping approach. Overall, fluxes were under the very dry conditions of the study years usually small with large temporal and spatial variations. Ammonium concentrations consistently and significantly correlated positively with N2O fluxes for all sites. Cumulative fluxes were often not significantly different from zero and apart from the rewetted alder forest, which was always a source of N2O, sites showed varying cumulative emission behavior (insignificant, source, potentially sink in one case) among years. Precipitation was positively correlated with cumulative fluxes on all drained sites and the rewetted alder forest. Isotope mapping indicated that N2O was always produced by more than one process simultaneously, with the estimated contribution of denitrification varying between 20 and 80%. N2O reduction played a potentially large role, with 5 to 50% of total emissions, showing large variations among sites and over time. Overall, neither the effect of rewetting, water level nor seasonality was clearly reflected in the fluxes or sources. Emissions were concentrated in hotspots and hot moments. A better understanding of the driving factors of N2O production and reduction in (rewetted) fens is essential and stable isotope methods including measurements of 15N and 18O as well as site preferences can help foster the necessary comprehension of the underlying mechanisms. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s10705-022-10244-y.
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Affiliation(s)
- Jacqueline Berendt
- Grassland and Fodder Sciences, Faculty of Agricultural and Environmental Sciences, University of Rostock, Rostock, Germany
- Present Address: Behörde für Umwelt, Klima, Energie und Agrarwirtschaft, Hamburg, Germany
| | - Gerald Jurasinski
- Landscape Ecology, Faculty of Agricultural and Environmental Sciences, University of Rostock, Rostock, Germany
| | - Nicole Wrage-Mönnig
- Grassland and Fodder Sciences, Faculty of Agricultural and Environmental Sciences, University of Rostock, Rostock, Germany
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The Impact of Using Novel Equations to Predict Nitrogen Excretion and Associated Emissions from Pasture-Based Beef Production Systems. SUSTAINABILITY 2022. [DOI: 10.3390/su14127260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The excretion of nitrogen (N) in faeces and urine from beef cattle contributes to atmospheric pollution through greenhouse gas and ammonia emissions and eutrophication of land and aquatic habitats through excessive N deposition and nitrate leaching to groundwater. As N excretion by beef cattle is rarely measured directly, it is important to accurately predict losses by utilising a combined knowledge of diet and production parameters so that the effect of dietary changes on the potential environmental impact of beef production systems can be estimated. This study aimed to identify differences between IPCC and more detailed country-specific models in the prediction of N excretion and N losses at a system level and determine how the choice of model influences the interpretation of differences in diet at the system scale. The data used in this study were derived from a farm-scale experimental system consisting of three individual grazing farms, each with a different sward type: a permanent pasture, a high sugar ryegrass monoculture, and a high sugar ryegrass with white clover (~30% groundcover). Data were analysed using a mixed linear model (residual maximum likelihood analysis). The IPCC methods demonstrated significantly lower estimates of N excretion than country-specific models for the first housing period and significantly greater losses for the grazing and second housing periods. The country-specific models enabled prediction of N partitioning to urine and faeces, which is important for estimation of subsequent N losses through the production system, although the models differed in their estimates. Overall, predicted N losses were greater using the IPCC approaches compared to using more detailed country-specific approaches. The outcomes of the present study have highlighted that different models can have a substantial impact on the predicted N outputs and subsequent losses to the environment for pasture-based beef finishing systems, and the importance, therefore, of using appropriate models and parameters.
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Effects of rumen undegradable protein sources on nitrous oxide, methane and ammonia emission from the manure of feedlot-finished cattle. Sci Rep 2022; 12:9166. [PMID: 35655074 PMCID: PMC9163071 DOI: 10.1038/s41598-022-13100-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 05/20/2022] [Indexed: 11/26/2022] Open
Abstract
The effects of sources of rumen undegradable protein (RUP) in diets on methane (CH4), nitrous oxide (N2O) and ammonia (NH3) emissions from the manure of feedlot-finished cattle were evaluated. We hypothesized that the use of different RUP sources in diets would reduce N loss via urine and contribute to reduced N2O, CH4 and NH3 emissions to the environment. Nellore cattle received different diets (18 animals/treatment), including soybean meal (SM, RDP source), by-pass soybean meal (BSM, RUP source) and corn gluten meal (CGM, RUP source). The protein source did not affect the N and C concentration in urine, C concentration in feces, and N balance (P > 0.05). The RUP sources resulted in a higher N2O emission than the RDP source (P = 0.030), while BSM resulted in a higher N2O emission than CGM (P = 0.038) (SM = 633, BSM = 2521, and CGM = 1153 g ha−2 N–N2O); however, there were no differences in CH4 and NH3 emission (P > 0.05). In conclusion, the use of RUP in diets did not affect N excretion of beef cattle or CH4 and NH3 emission from manure, but increased N2O emission from the manure.
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Liu H, Li Y, Pan B, Zheng X, Yu J, Ding H, Zhang Y. Pathways of soil N 2O uptake, consumption, and its driving factors: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:30850-30864. [PMID: 35092587 DOI: 10.1007/s11356-022-18619-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 01/07/2022] [Indexed: 06/14/2023]
Abstract
Nitrous oxide (N2O) is an important greenhouse gas that plays a significant role in atmospheric photochemical reactions and contributes to stratospheric ozone depletion. Soils are the main sources of N2O emissions. In recent years, it has been demonstrated that soil is not only a source but also a sink of N2O uptake and consumption. N2O emissions at the soil surface are the result of gross N2O production, uptake, and consumption, which are co-occurring processes. Soil N2O uptake and consumption are complex biological processes, and their mechanisms are still worth an in-depth systematic study. This paper aimed to systematically address the current research progress on soil N2O uptake and consumption. Based on a bibliometric perspective, this study has highlighted the pathways of soil N2O uptake and consumption and their driving factors and measurement techniques. This systematic review of N2O uptake and consumption will help to further understand N transformations and soil N2O emissions.
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Affiliation(s)
- Hongshan Liu
- College of Earth Sciences, Jilin University, Chao'yang, Changchun, 130061, Jilin, People's Republic of China
- Institute of Soil and Fertilizer, Fujian Academy of Agricultural Sciences/ Fujian Key Laboratory of Plant Nutrition and Fertilizer, Jin'an, Fuzhou, 350013, Fujian, People's Republic of China
| | - Yuefen Li
- College of Earth Sciences, Jilin University, Chao'yang, Changchun, 130061, Jilin, People's Republic of China.
| | - Baobao Pan
- School of Agriculture and Food, The University of Melbourne, Parkville, 3010, VIC, Australia
| | - Xiangzhou Zheng
- Institute of Soil and Fertilizer, Fujian Academy of Agricultural Sciences/ Fujian Key Laboratory of Plant Nutrition and Fertilizer, Jin'an, Fuzhou, 350013, Fujian, People's Republic of China
| | - Juhua Yu
- Institute of Soil and Fertilizer, Fujian Academy of Agricultural Sciences/ Fujian Key Laboratory of Plant Nutrition and Fertilizer, Jin'an, Fuzhou, 350013, Fujian, People's Republic of China
| | - Hong Ding
- Institute of Soil and Fertilizer, Fujian Academy of Agricultural Sciences/ Fujian Key Laboratory of Plant Nutrition and Fertilizer, Jin'an, Fuzhou, 350013, Fujian, People's Republic of China
| | - Yushu Zhang
- Institute of Soil and Fertilizer, Fujian Academy of Agricultural Sciences/ Fujian Key Laboratory of Plant Nutrition and Fertilizer, Jin'an, Fuzhou, 350013, Fujian, People's Republic of China.
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11
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Ma L, Janz B, Kiese R, Mwanake R, Wangari E, Butterbach-Bahl K. Effect of vole bioturbation on N 2O, NO, NH 3, CH 4 and CO 2 fluxes of slurry fertilized and non-fertilized montane grassland soils in Southern Germany. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 800:149597. [PMID: 34426336 DOI: 10.1016/j.scitotenv.2021.149597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 08/02/2021] [Accepted: 08/07/2021] [Indexed: 06/13/2023]
Abstract
Populations of rodents such as common vole (Microtus arvalis) can develop impressive soil bioturbation activities in grasslands. These burrowing and nesting activities highly impact soil physicochemical properties as well as vegetation coverage and diversity. Managed grasslands in livestock production regions receive significant amounts of slurry, commonly at high loads at the beginning of the vegetation period. However, nothing is known how the combination of vole bioturbation and slurry application may affect the fluxes of C and N trace gases from grasslands. Here we report on an in-situ experiment and supporting laboratory incubations carried out during the period March to May 2020 comparing C (CH4, CO2) and N (N2O, NO, NH3) trace gas fluxes from Lolium perenne and Trifolium repens dominated montane grasslands with and without vole bioturbation and with and without slurry application, whereby, with regard to the latter, we further differentiated between acidified and non-acidified slurry. Vole bioturbation significantly (p < 0.05) increased soil NO and NH3 emissions, while N2O fluxes were only significantly (p < 0.05) enhanced in vole affected grassland patches following slurry application (+17%). Effects of vole bioturbation on CH4 fluxes were non-significant, while slurry application significantly reduced CH4 uptake. Compared to applications of non-acidified slurry, application of acidified slurry significantly (p < 0.05) reduced NH3 volatilization by approx. 38% and 50%, for vole and non-vole affected grassland patches, respectively. A significant effect of acidified slurry application on soil NO emissions was only observed for vole affected grassland patches. Significant (p < 0.05) reductions in aboveground net primary productivity and reduced plant N uptake are likely the main mechanisms explaining the stimulation of gaseous N losses following slurry application. Long-term measurements are needed to better understand effects of vole bioturbation on grassland soil C and N cycling and ecosystem GHG balance.
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Affiliation(s)
- Lei Ma
- Institute of Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, Garmisch-Partenkirchen 82467, Germany; College of Atmospheric Sciences, Lanzhou University, No. 222 Tian-shui South Road, Cheng-guan District, Lanzhou 730000, PR China
| | - Baldur Janz
- Institute of Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, Garmisch-Partenkirchen 82467, Germany
| | - Ralf Kiese
- Institute of Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, Garmisch-Partenkirchen 82467, Germany
| | - Ricky Mwanake
- Institute of Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, Garmisch-Partenkirchen 82467, Germany
| | - Elizabeth Wangari
- Institute of Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, Garmisch-Partenkirchen 82467, Germany
| | - Klaus Butterbach-Bahl
- Institute of Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, Garmisch-Partenkirchen 82467, Germany.
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12
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Lv P, Zuo X, Sun S, Zhang J, Zhao S, Hu Y. Seasonal Changes of Soil Nitrogen Mineralization Along Restoration Gradient of Sandy Grassland, Northern China. POLISH JOURNAL OF ECOLOGY 2021. [DOI: 10.3161/15052249pje2020.68.4.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Peng Lv
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou,730000, China
| | - Xiaoan Zuo
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou,730000, China
| | - Shanshan Sun
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou,730000, China
| | - Jing Zhang
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou,730000, China
| | - Shenglong Zhao
- Urat Desert-grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou,730000, China
| | - Ya Hu
- Urat Desert-grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou,730000, China
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13
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McAuliffe G, López-Aizpún M, Blackwell M, Castellano-Hinojosa A, Darch T, Evans J, Horrocks C, Le Cocq K, Takahashi T, Harris P, Lee M, Cardenas L. Elucidating three-way interactions between soil, pasture and animals that regulate nitrous oxide emissions from temperate grazing systems. AGRICULTURE, ECOSYSTEMS & ENVIRONMENT 2020; 300:106978. [PMID: 32943807 PMCID: PMC7307388 DOI: 10.1016/j.agee.2020.106978] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/06/2020] [Accepted: 04/24/2020] [Indexed: 06/11/2023]
Abstract
Pasture-based livestock farming contributes considerably to global emissions of nitrous oxide (N2O), a powerful greenhouse gas approximately 265 times more potent than carbon dioxide. Traditionally, the estimation of N2O emissions from grasslands is carried out by means of plot-scale experiments, where externally sourced animal excreta are applied to soils to simulate grazing conditions. This approach, however, fails to account for the impact of different sward types on the composition of excreta and thus the functionality of soil microbiomes, creating unrealistic situations that are seldom observed under commercial agriculture. Using three farming systems under contrasting pasture management strategies at the North Wyke Farm Platform, an instrumented ruminant grazing trial in Devon, UK, this study measured N2O emissions from soils treated with cattle urine and dung collected within each system as well as standard synthetic urine shared across all systems, and compared these values against those from two forms of controls with and without inorganic nitrogen fertiliser applications. Soil microbial activity was regularly monitored through gene abundance to evaluate interactions between sward types, soil amendments, soil microbiomes and, ultimately, N2O production. Across all systems, N2O emissions attributable to cattle urine and standard synthetic urine were found to be inconsistent with one another due to discrepancy in nitrogen content. Despite previous findings that grasses with elevated levels of water-soluble carbohydrates tend to generate lower levels of N2O, the soil under high sugar grass monoculture in this study recorded higher emissions when receiving excreta from cattle fed the same grass. Combined together, our results demonstrate the importance of evaluating environmental impacts of agriculture at a system scale, so that the feedback mechanisms linking soil, pasture, animals and microbiomes are appropriately considered.
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Affiliation(s)
- G.A. McAuliffe
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
| | - M. López-Aizpún
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
| | - M.S.A. Blackwell
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
| | - A. Castellano-Hinojosa
- University of Florida, IFAS Southwest Florida Research and Education Center, Immokalee, FL, 34142, USA
| | - T. Darch
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
| | - J. Evans
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
| | - C. Horrocks
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
| | - K. Le Cocq
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
| | - T. Takahashi
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
- University of Bristol, Bristol Veterinary School, Langford, Somerset, BS40 5DU, UK
| | - P. Harris
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
| | - M.R.F Lee
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
- University of Bristol, Bristol Veterinary School, Langford, Somerset, BS40 5DU, UK
| | - L. Cardenas
- Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
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14
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Charteris AF, Chadwick DR, Thorman RE, Vallejo A, de Klein CAM, Rochette P, Cárdenas LM. Global Research Alliance N 2 O chamber methodology guidelines: Recommendations for deployment and accounting for sources of variability. JOURNAL OF ENVIRONMENTAL QUALITY 2020; 49:1092-1109. [PMID: 33016455 DOI: 10.1002/jeq2.20126] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 06/25/2020] [Accepted: 07/02/2020] [Indexed: 06/11/2023]
Abstract
Adequately estimating soil nitrous oxide (N2 O) emissions using static chambers is challenging due to the high spatial variability and episodic nature of these fluxes. We discuss how to design experiments using static chambers to better account for this variability and reduce the uncertainty of N2 O emission estimates. This paper is part of a series, each discussing different facets of N2 O chamber methodology. Aspects of experimental design and sampling affected by spatial variability include site selection and chamber layout, size, and areal coverage. Where used, treatment application adds a further level of spatial variability. Time of day, frequency, and duration of sampling (both individual chamber closure and overall experiment duration) affect the temporal variability captured. We also present best practice recommendations for chamber installation and sampling protocols to reduce further uncertainty. To obtain the best N2 O emission estimates, resources should be allocated to minimize the overall uncertainty in line with experiment objectives. Sometimes this will mean prioritizing individual flux measurements and increasing their accuracy and precision by, for example, collecting four or more headspace samples during each chamber closure. However, where N2 O fluxes are exceptionally spatially variable (e.g., in heterogeneous agricultural landscapes, such as uneven and woody grazed pastures), using available resources to deploy more chambers with fewer headspace samples per chamber may be beneficial. Similarly, for particularly episodic N2 O fluxes, generated for example by irrigation or freeze-thaw cycles, increasing chamber sampling frequency will improve the accuracy and reduce the uncertainty of temporally interpolated N2 O fluxes.
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Affiliation(s)
- Alice F Charteris
- Sustainable Agriculture Sciences, Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
| | - David R Chadwick
- School of Natural Sciences, Bangor Uni., Bangor, Gwynedd, LL57 2UW, UK
| | - Rachel E Thorman
- ADAS Boxworth, Battlegate Road, Boxworth, Cambridge, CB23 4NN, UK
| | - Antonio Vallejo
- ETSIABB and Centro de Estudios e Investigación para la Gestión de Riesgos, Agrarios y Medioambientales (CEIGRAM), Univ. Politécnica de Madrid, Ciudad Universitaria s/n, Madrid, 28040, Spain
| | - Cecile A M de Klein
- Invermay Agricultural Centre, AgResearch, Private Bag 50034, Mosgiel, 9053, New Zealand
| | - Philippe Rochette
- The Quebec Research and Development Centre, Agriculture and Agri-Food Canada, 2560 Hochelaga Boulevard, Québec, QC, G1V 2J3, Canada
| | - Laura M Cárdenas
- Sustainable Agriculture Sciences, Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, UK
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15
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Castellano‐Hinojosa A, Loick N, Dixon E, Matthews GP, Lewicka‐Szczebak D, Well R, Bol R, Charteris A, Cardenas L. Improved isotopic model based on 15 N tracing and Rayleigh-type isotope fractionation for simulating differential sources of N 2 O emissions in a clay grassland soil. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33:449-460. [PMID: 30561863 PMCID: PMC6492082 DOI: 10.1002/rcm.8374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 12/12/2018] [Accepted: 12/12/2018] [Indexed: 06/09/2023]
Abstract
RATIONALE Isotopic signatures of N2 O can help distinguish between two sources (fertiliser N or endogenous soil N) of N2 O emissions. The contribution of each source to N2 O emissions after N-application is difficult to determine. Here, isotopologue signatures of emitted N2 O are used in an improved isotopic model based on Rayleigh-type equations. METHODS The effects of a partial (33% of surface area, treatment 1c) or total (100% of surface area, treatment 3c) dispersal of N and C on gaseous emissions from denitrification were measured in a laboratory incubation system (DENIS) allowing simultaneous measurements of NO, N2 O, N2 and CO2 over a 12-day incubation period. To determine the source of N2 O emissions those results were combined with both the isotope ratio mass spectrometry analysis of the isotopocules of emitted N2 O and those from the 15 N-tracing technique. RESULTS The spatial dispersal of N and C significantly affected the quantity, but not the timing, of gas fluxes. Cumulative emissions are larger for treatment 3c than treatment 1c. The 15 N-enrichment analysis shows that initially ~70% of the emitted N2 O derived from the applied amendment followed by a constant decrease. The decrease in contribution of the fertiliser N-pool after an initial increase is sooner and larger for treatment 1c. The Rayleigh-type model applied to N2 O isotopocules data (δ15 Nbulk -N2 O values) shows poor agreement with the measurements for the original one-pool model for treatment 1c; the two-pool models gives better results when using a third-order polynomial equation. In contrast, in treatment 3c little difference is observed between the two modelling approaches. CONCLUSIONS The importance of N2 O emissions from different N-pools in soil for the interpretation of N2 O isotopocules data was demonstrated using a Rayleigh-type model. Earlier statements concerning exponential increase in native soil nitrate pool activity highlighted in previous studies should be replaced with a polynomial increase with dependency on both N-pool sizes.
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Affiliation(s)
- Antonio Castellano‐Hinojosa
- Department of Microbiology, Faculty of PharmacyUniversity of Granada. Campus Cartuja18071GranadaSpain
- Department of Soil Microbiology and Symbiotic SystemsEstación Experimental del Zaidín18080GranadaSpain
| | - Nadine Loick
- Rothamsted Research, North WykeOkehamptonEX20 2SBUK
| | | | - G. Peter Matthews
- School of Geography, Earth and Environmental SciencesUniversity of PlymouthDavy Building, Drake CircusPlymouthPL4 8AAUK
| | | | - Reinhard Well
- Thünen Institute of Climate‐Smart AgricultureBundesallee 6538116BraunschweigGermany
| | - Roland Bol
- Agrosphere (IBG‐3)Institute of Bio‐ and GeosciencesForschungszentrum Jülich52428JülichGermany
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