Nitrogen isotope fractionation mechanism, analysis measurement tracer technology and its application in ecological environment

LI Siyuan; HOU Qingye; YANG Zhongfang; YU Tao

doi:10.12029/gc20230910002

2024 Vol. 51, No. 5

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Article navigation > Geology in China > 2024 > 51(5): 1617-1643

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LI Siyuan, HOU Qingye, YANG Zhongfang, YU Tao. 2024. Nitrogen isotope fractionation mechanism, analysis measurement tracer technology and its application in ecological environment[J]. Geology in China, 51(5): 1617-1643. doi: 10.12029/gc20230910002

Citation:

LI Siyuan, HOU Qingye, YANG Zhongfang, YU Tao. 2024. Nitrogen isotope fractionation mechanism, analysis measurement tracer technology and its application in ecological environment[J]. Geology in China, 51(5): 1617-1643. doi: 10.12029/gc20230910002

Nitrogen isotope fractionation mechanism, analysis measurement tracer technology and its application in ecological environment

1.
School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China
2.
School of Science, China University of Geosciences, Beijing 100083, China

Fund Project: Supported by the National Natural Science Foundation of China (No.41773019).

More Information

Author Bio: LI Siyuan, female, born in 1998, master candidate, majors in environmental geochemistry research; E-mail: 601321603@qq.com
Corresponding author: HOU Qingye, female, born in 1978, professor, majors in environmental geochemistry research; E-mail: qingyehou@cugb.edu.cn.

Received Date: 10 September 2023

Revised Date: 29 January 2024

Publish Date: 25 September 2024

Abstract

Abstract

This paper is the result of environmental geological survey engineering.
Objective
Nitrogen (N) is a key nutrient across Earth's terrestrial ecosystems and one of the pollution elements that cause water eutrophication. Owing to the continuous improvements of analysis and testing techniques, nitrogen stable isotope technology has developed into a common research method and analysis mean, and has been widely used in nitrogen biogeochemical cycle, water eutrophication and groundwater pollution source identification.
Methods
In this paper, the relevant literatures on nitrogen stable isotope in the field of ecological environment domestic and overseas in recent years were reviewed, and the research status of nitrogen isotope fractionation mechanism, nitrogen stable isotope analysis technology and nitrogen isotope applications in ecological environment were summarized, the development of remediation technologys of nitrate pollution in groundwater were briefly described.
Results
(1) A mature system of nitrogen isotope mass spectrometry and nitrogen isotope tracer technology has been established. (2) Nitrification and denitrification are the main mechanisms of soil nitrogen conversion cycle. Nitrogen input is realized by biological nitrogen fixation, and nitrogen output is mainly through nitrogen gas or ammoniation produced by plants or microorganisms, which is accompanied by different degrees of nitrogen isotope fractionation. (3) Nitrogen isotopes can be used to measure soil nitrogen turnover rates and N₂O emission rates, improve biological nitrogen fixation, indicate changes in atmospheric nitrogen deposition, investigate the interaction between plant and soil and determine nitrogen uptake and utilization by plants, and identify crop area sources and pollution in groundwater and atmosphere.
Conclusions
Future researches should focus on improving the ability of quantitative detection of uncertainty sources in the nitrogen cycle, identifying undiscovered nitrogen input, accumulation and loss pathways, and perfecting and developing ecosystem nitrogen cycle model.
- nitrogen isotope /
- fractionation mechanisms /
- δ¹⁵N /
- tracer technology /
- ecological environment /
- influencing factors /
- environmental geological survey engineering

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References

[1]	Ahmed M, Aly A, Gomaa H. 2012. Developed method for nitrate extraction and purification to measure δ¹⁸O−NO₃⁻composition in water[J]. Arab Journal of Nuclear Sciences and Applications, 45(4): 1−13. Google Scholar
[2]	Alexander B, Mickley L J. 2015. Paleo−perspectives on potential future changes in the oxidative capacity of the atmosphere due toclimate change and anthropogenic emissions[J]. Current Pollution Reports, 1(2): 57−69. doi: 10.1007/s40726-015-0006-0 CrossRef Google Scholar
[3]	An H, Li G Q. 2015. Efects of grazing on carbon and nitrogen in plants and soils in a semiarid desert grassland, China[J]. Journal of Arid Land, 7(3): 341−349. doi: 10.1007/s40333-014-0049-x CrossRef Google Scholar
[4]	Aranibar J N, Otter L, Macko S A, Epstein H E, Otter L, Dowty P R. 2004. Nitrogen cycling in the soil−plant system along a precipitation gradient in the Kalahari sands[J]. Global Change Biology, 10(3): 359−373. doi: 10.1111/j.1365-2486.2003.00698.x CrossRef Google Scholar
[5]	Archana A, Thibodeau B, Geeraert N, Xu M N, Kao S J, Baker D M. 2018. Nitrogen sources and cycling revealed by dual isotopes of nitrate in a complex urbanized environment[J]. Water Research, 142: 459−470. doi: 10.1016/j.watres.2018.06.004 CrossRef Google Scholar
[6]	Baggs E M. 2008. A review of stable isotope techniques for N₂O source partitioning in soils: Recent progress, remaining challenges and future considerations[J]. Rapid Communications in Mass Spectrometry, 22: 1664−1672. doi: 10.1002/rcm.3456 CrossRef Google Scholar
[7]	Bai X, Hu X J, Liu J J, Wei D, Zhu P, Cui X, Zhou B K, Chen X L, Liu J D, Jin J, Liu X B, Wang G H. 2022. Ammonia oxidizing bacteria dominate soil nitrification under different fertilization regimes in black soils of northeast China[J]. European Journal of Soil Biology, 111: 103410. doi: 10.1016/j.ejsobi.2022.103410 CrossRef Google Scholar
[8]	Berner A H, Felix J D. 2020. Investigating ammonia emissions in a coastal urban airshed using stable isotope techniques[J]. The Science of the Total Environment, 707: 134952. doi: 10.1016/j.scitotenv.2019.134952 CrossRef Google Scholar
[9]	Booth M S, Stark J M, Rastetter E. 2005. Controls on nitrogen cycling in terrestrial ecosystems: A synthetic analysis of literature data[J]. Ecological Monographs, 75(2): 139−157. doi: 10.1890/04-0988 CrossRef Google Scholar
[10]	Bork E W, Attaeianb B, Cahillc J F, Changd S X. 2019. Soil nitrogen and greenhouse gas dynamics in a temperate grassland under experimental warming and defoliation[J]. Soil Science Society of America Journal, 83(3): 780−790. doi: 10.2136/sssaj2018.04.0150 CrossRef Google Scholar
[11]	Briand C, Plagnes, V, Sebilo M, Louvat P, Chesnot T, Schneider M, Ribstein P, Marchet P. 2013. Combination of nitrate(N, O) and boron isotopic ratios with microbiological indicators for the determination of nitrate sources in karstic groundwater[J]. Environmental Chemistry, 10(5): 365−369. doi: 10.1071/EN13036 CrossRef Google Scholar
[12]	Briand C, Sebilo M, Louvat P, Chesno T, Vaury V, Schneider M, Plagnes V. 2017. Legacy of contaminant N sources to the NO₃⁻signature in rivers: a combined isotopic (δ¹⁵N−NO₃⁻, δ¹⁸O−NO₃⁻, δ¹¹B) and microbiological investigation[J]. Scientific Reports, 7: 41703. doi: 10.1038/srep41703 CrossRef Google Scholar
[13]	Buchen C, Lewicka−Szczebak D, Flessa H, Well R. 2018. Estimating N₂O processes during grassland renewal and grassland conversion to maize cropping using N₂O isotopocules[J]. Rapid Communications in Mass Spectrometry, 32(13): 1053−1067. doi: 10.1002/rcm.8132 CrossRef Google Scholar
[14]	Byrnes R C, Nùnez J, Arenas L, Rao I, Trujillo C, Alvarez C. 2017. Biological nitrification inhibition by Brachiaria grasses mitigates soil nitrous oxide emissions from bovine urine patches[J]. Soil Biology & Biochemistry, 107(1): 156−163. Google Scholar
[15]	Cao Yacheng, Zhang Jinbo, Wen Teng. 2018. Application of Stable Isotope Tracer Technology and Mass Spectrometry in Soil, Ecology and Environment Research [M]. Beijing: Science Press (in Chinese). Google Scholar
[16]	Chalk P, Smith C. 2021. On inorganic N uptake by vascular plants: Can¹⁵N tracer techniques resolve the NH₄⁺ versus NO₃⁻ “preference” conundrum?[J]. European Journal of Soil Science, 72(4): 1762−1779. doi: 10.1111/ejss.13069 CrossRef Google Scholar
[17]	Chapagain T, Riseman A. 2014. Barley−pea intercropping: Effects on land productivity, carbon and nitrogen transformations[J]. Field Crops Research, 166: 18−25. doi: 10.1016/j.fcr.2014.06.014 CrossRef Google Scholar
[18]	Chen Z M, Ding W X, Xu Y H, Müller C, Rütting T, Yu H Y, Fan J L, Zhang J B, Zhu T B. 2015. Importance of heterotrophic nitrification and dissimilatory nitrate reduction to ammonium in a cropland soil: Evidences from a ¹⁵N tracing study to literature synthesis[J]. Soil Biology and Biochemistry, 91: 65−75. doi: 10.1016/j.soilbio.2015.08.026 CrossRef Google Scholar
[19]	Chen Z X, Liu G, Liu W G, Lam M H W, Liu G J, Yin X B. 2012. Identification of nitrate sources in Taihu Lakeand its major inflow rivers in China, using δ¹⁵N−NO₃⁻ and δ¹⁸O−NO₃⁻ values[J]. Water Science & Technology, 66(3): 536−542. Google Scholar
[20]	Cheng Y, Wang J, Chang S X, Cai Z C, Müller C, Zhang J B. 2019. Nitrogen deposition affects both net and gross soil nitrogen transformations in forest ecosystems: A review[J]. Environmental Pollution (Barking, Essex: 1987), 244: 608−616. Google Scholar
[21]	Cheng Y, Wang J, Wang S Q, Zhang J B, Cai Z C. 2014. Effects of soil moisture on gross N transformations and N₂O emission in acid subtropical forest soils[J]. Biology and Fertility of Soils, 50(7): 1099−1108. doi: 10.1007/s00374-014-0930-y CrossRef Google Scholar
[22]	Choi W J, Kwak J H, Lim S S, Park, H J, Chang S X, Lee S M, Arshad M A, Yun S I, Kim H Y. 2017. Synthetic fertilizer and livestock manure differently affect δ¹⁵N in the agricultural landscape: A review[J]. Agriculture, Ecosystems & Environment, 237: 1−15. Google Scholar
[23]	Choi W J, Kwak J H, Park H J, Yang H I, Park S I, Xu Z, Lee S M, Lim S S, Chang S X. 2020. Land−use type, and land management and disturbance affect soil δ¹⁵N: A review[J]. Soils Sediments, 20: 3283−3299. doi: 10.1007/s11368-020-02708-x CrossRef Google Scholar
[24]	Choi W J, Lee S M, Chang S X, Ro H M. 2005. Variations of δ¹³C and δ¹⁵N in Pinus Densiflora tree−rings and relationship to environmental changes in eastern Korea[J]. Water Air and Soil Pollution, 164(1): 173−187. Google Scholar
[25]	Choi W J, Park H J, Baek N, Yang H I, Kwak J H, Lee S, Park S W, Shin E S, Lim S S. 2023. Patterns of δ¹⁵N in forest soils and tree foliage and rings between climate zones in relation to atmospheric nitrogen deposition: A review[J]. Science of the Total Environment, 900: 165866. doi: 10.1016/j.scitotenv.2023.165866 CrossRef Google Scholar
[26]	Choi W J, Ro H M. 2003. Differences in isotopic fractionation of nitrogen in water−saturated and unsaturated soils[J]. Soil Biology & Biochemistry, 35(3): 483−486. Google Scholar
[27]	Cookson W R, Osman M, Marschner P, Abaye D A , Clark I, Murphy D V, Stockdale E A, Watson C A. 2007. Controls on soil nitrogen cycling and microbial community composition across land use and incubation temperature[J]. Soil Biology and Biochemistry, 39(3): 744−756. Google Scholar
[28]	Craine J, Brookshire E, Cramer M, Hasselquist N, Koba K, Marin−Spiotta E, Wang L X. 2015. Ecological interpretations of nitrogen isotope ratios of terrestrial plants and soils[J]. Plant and Soil, 396(1/2): 1−26. Google Scholar
[29]	Craine J M, Elmore A J, Wang L X. 2018. Isotopic evidence for oligotrophication of terrestrial ecosystems[J]. Nature Ecology & Evolution, 2: 1735−1744. Google Scholar
[30]	Dähnke K, Thamdrup B. 2016. Isotope fractionation and isotope decoupling during anammox and denitrification in marine sediments[J]. Limnology and Oceanography, 61(2): 610−624. doi: 10.1002/lno.10237 CrossRef Google Scholar
[31]	Decock C, Six J. 2013. How reliable is the intramolecular distribution of ¹⁵N in N₂O to source partition N₂O emitted from soil?[J]. Soil Biology and Biochemistry, 65: 114−127. doi: 10.1016/j.soilbio.2013.05.012 CrossRef Google Scholar
[32]	Denk T R A, Butterbach−Bahl K, Kiese R, Wolf B, Mohn J, Harris E Decock C, Lewicka−Szczebak Dominika. 2017. The nitrogen cycle: A review of isotope effects and isotope modeling approaches[J]. Soil Biology & Biochemistry, 105: 121−137. Google Scholar
[33]	Deutsch B, Mewes M, Liskow I, Voss M. 2006. Quantification of diffuse nitrate inputs into a small river system using stable isotopes of oxygen and nitrogen in nitrate[J]. Organic Geochemistry, 37(10): 1333−1342. doi: 10.1016/j.orggeochem.2006.04.012 CrossRef Google Scholar
[34]	Ding J T, Xi B D, Gao R T, He L Sg, Liu H L, Dai X L, Yu Y J. 2014. Identifying diffused nitrate sources in a stream in an agricultural field using a dual isotopic approach[J]. Science of The Total Environment, 484: 10−18. doi: 10.1016/j.scitotenv.2014.03.018 CrossRef Google Scholar
[35]	Du E, Terrer C, Pellegrini A F A, Ahlström A, Lissa C J V, Zhao Xia, Xia Nan, Wu Xinhui, Jackson R B. 2020. Global patterns of terrestrial nitrogen and phosphorus limitation[J]. Nature Geoscience, 13(3): 221−226. doi: 10.1038/s41561-019-0530-4 CrossRef Google Scholar
[36]	Duan L, Wu Y K, Fan J H, Ye F, Xie C C, Fu X Y, Sun Y Q. 2023. Identification of nitrogen pollution sources and transport transformation processes in groundwater of different landforms using C, H, N, and O isotope techniques: An example from the lower Weihe River[J]. Environmental Science and Pollution Research International, 30(11): 1614−7499. Google Scholar
[37]	Elrys A S, Ali A, Zhang H M, Cheng Y, Zhang J B, Cai Z C, Müller C, Chang S X. 2021. Patterns and drivers of global gross nitrogen mineralization in soils[J]. Global Change Biology, 27(22): 5950−5962. doi: 10.1111/gcb.15851 CrossRef Google Scholar
[38]	Escanhoela A S B, Pitombo L M, Brandani C B, Navarrete A A, Bento C B, do Carmo J B. 2019. Organic management increases soil nitrogen but not carbon content in a tropical citrus orchard with pronounced N₂O emissions[J]. Journal of Environmental Management, 234: 326−335. doi: 10.1016/j.jenvman.2018.11.109 CrossRef Google Scholar
[39]	Feng Xiaomin, Gao Xiang, Zang Huadong, Hu Yuegao, Ren Changzhong, Hao Zhiping, Lü Huiqing, Zeng Zhaohai. 2023. Effects of oat and mung bean intercropping and nitrogen transfer characteristics[J]. Chinese Bulletin of Botany, 58(1): 122−131 (in Chinese with English abstract). Google Scholar
[40]	Frey C, Hietanen S, Jürgens K, Labrenz M, Voss Maren. 2014. N and O isotope fractionation in nitrate during chemolithoautotrophic denitrification by sulfurimonas gotlandica[J]. Environmental Science & Technology, 48(22): 13229−13237. Google Scholar
[41]	Fukada T, Hiscock K M, Dennis P F, Grischek T. 2003. A dual isotope approach to identify denitrification in groundwater at a river−bank infiltration site[J]. Water Research, 37(13): 3070−3078. doi: 10.1016/S0043-1354(03)00176-3 CrossRef Google Scholar
[42]	Gao L, Cui X Y, Hill P W, Guo T F. 2020. Uptake of various nitrogen forms by co−existing plant species in temperate and cold−temperate forests in northeast China[J]. Applied Soil Ecology, 147: 103398. doi: 10.1016/j.apsoil.2019.103398 CrossRef Google Scholar
[43]	Gao W, Yan D. 2019. Warming suppresses microbial biomass but enhances N recycling[J]. Soil Biology and Biochemistry, 131: 111−118. doi: 10.1016/j.soilbio.2019.01.002 CrossRef Google Scholar
[44]	Gerhart L M, McLauchlan K K. 2014. Reconstructing terrestrial nutrient cycling using stable nitrogen isotopes in wood[J]. Biogeochemistry, 120(1): 1−21. Google Scholar
[45]	Groffman P M, Altabet M A, Böhlke J K. 2006. Methods for measuring denitrification: Diverse approaches to a difficult problem[J]. Ecological Applications, 16(6): 2091−2122. doi: 10.1890/1051-0761(2006)016[2091:MFMDDA]2.0.CO;2 CrossRef Google Scholar
[46]	Guo K Y, Yang J, Yu N, Luo L, Wang E T. 2023. Biological nitrogen fixation in cereal crops: Progress, strategies and perspectives[J]. Plant Communications, 4(2): 100499 doi: 10.1016/j.xplc.2022.100499 CrossRef Google Scholar
[47]	Halm H, Lam P, Ferdelman T G, Lavik G, Dittmar T, LaRoche J, D’Hondt S, Kuypers M M M. 2012. Heterotrophic organisms dominate nitrogen fixation in the South Pacific Gyre[J]. The ISME Journal, 6(6): 1238−1249. doi: 10.1038/ismej.2011.182 CrossRef Google Scholar
[48]	Hastings M G, Casciotti K L, Elliott E M. 2013. Stable isotopes as tracers of anthropogenic nitrogen sources, deposition, and impacts[J]. Elements, 9(5): 339−344. doi: 10.2113/gselements.9.5.339 CrossRef Google Scholar
[49]	Hauggaard−Nielsen H, Gooding M, Ambus P, Corre−Hellou G, Crozat Y, Dahlmann C, Dibet A, Von Fragstein P, Pristeri A, Monti M, Jensen E S. 2009. Pea–barley intercropping for efficient symbiotic N₂−fixation, soil N acquisition and use of other nutrients in European organic cropping systems[J]. Field Crops Research, 113(1): 64−71. doi: 10.1016/j.fcr.2009.04.009 CrossRef Google Scholar
[50]	Hoefs J. 2021. Stable Isotope Geochemistry[M]. BerLin: Springer International Publishing. Google Scholar
[51]	Hosono T, Alvarez K, Li I T, Shimada J. 2015. Nitrogen, carbon, and sulfur isotopic change during heterotrophic (Pseudomonas aureofaciens) and autotrophic (Thiobacillus denitrificans) denitrification reactions[J]. Journal of Contaminant Hydrology, 183: 72−81. doi: 10.1016/j.jconhyd.2015.10.009 CrossRef Google Scholar
[52]	Hu H W, Xu Z H, He J Z. 2014. Ammonia−oxidizing archaea play a predominant role inacid soil nitrification[J]. Advances in Agronomy, 125: 261−302. Google Scholar
[53]	Huang Qiaoqiao, Xu Hui, Fan Zhiwei, Hou Yuping. 2013. Effects of loblolly tree invasion on soil chemical properties of young black pine forest[J]. Journal of Ecology and Environment, 22(7): 119−1123 (in Chinese). Google Scholar
[54]	Huang T, Gao B, Hu X K, Lu X, Well R, Christie P, Bakken L R, Ju X T. 2014. Ammonia−oxidation as an engine to generate nitrous oxide in an intensively managed calcareous fluvo−aquic soil[J]. Scientific Reports, 4(1): 3950. doi: 10.1038/srep03950 CrossRef Google Scholar
[55]	Jeong Y J, Park H J, Jeon B J, Seo B S, Baek N, Yang H I, Kwak J H, Lee S M, Choi W J. 2022. Land use types with diferent fertilization management affected isotope ratios of bulk and water−extractable C and N of soils in an intensive agricultural area[J]. Soils Sediments, 22: 429−442. doi: 10.1007/s11368-021-03097-5 CrossRef Google Scholar
[56]	Jiang L L, Wang S P, Pang Z, Wang C S, Kardol P, Zhou X Q, Rui Y C, Lan Z C, Wang Y F, Xu X L. 2015. Grazing modifies inorganic and organic nitrogen uptake by coexisting plant species in alpine grassland[J]. Biology & Fertility of Soils, 52(2): 211−221. Google Scholar
[57]	Jiang Y Q, Xing J, Wang S X, Chang X, Liu S C, Shi A J, Liu B X, Sahu S K. 2021. Understand the local and regional contributions on air pollution from the view of human health impacts[J]. Frontiers of Environmental Science & Engineering, 15(5): 88. Google Scholar
[58]	Jung H J, Koh D C, Yun S K, Jeen S W, Lee J. 2020. Stable isotopes of water and nitrate for the identification of groundwater flowpaths: A review[J]. Water, 12(1): 138. doi: 10.3390/w12010138 CrossRef Google Scholar
[59]	Kaushal R, Hsueh Y H, Chen C L, Lan Y P, Wu P Y, Chen Y C, Liang M C. 2022. Isotopic assessment of soil N₂O emission from a sub−tropical agricultural soil under varying N−inputs[J]. Science of the Total Environment, 827: 154311. doi: 10.1016/j.scitotenv.2022.154311 CrossRef Google Scholar
[60]	Kellman L M. 2005. A study of tile drain nitrate−δ¹⁵N values as a tool for assessing nitrate sources in an agricultural region[J]. Nutrient Cycling in Agroecosystems, 71(2): 131−137. doi: 10.1007/s10705-004-1925-0 CrossRef Google Scholar
[61]	Kemmitt S J, Wright D, Goulding K W, Jones D L. 2006. pH regulation of carbon and nitrogen dynamics in two agricultural soils[J]. Soil Biology & Biochemistry, 38(5): 898−911. Google Scholar
[62]	Kendall C, Elliott E M, Wankel S D. 2007. Tracing anthropogenic inputs of nitrogen to ecosystems[J]. Stable Isotopes in Ecology and Environmental Science: 375−449. Google Scholar
[63]	Kendall C. 1998. Chapter 16−Tracing Nitrogen Sources and Cycling in Catchments. Isotope Tracers in Catchment Hydrology [M]. Elsevier Science, 519−576. Google Scholar
[64]	Kuypers M M M, Marchant H K, Kartal B. 2018. The microbial nitrogen−cycling network[J]. Nature Reviews Microbiology, 16: 263−276. doi: 10.1038/nrmicro.2018.9 CrossRef Google Scholar
[65]	Kwak J H, Lim S S, Chang S X, Lee K H. 2011. Potential use of δ¹³C, δ¹⁵N, N concentration, and Ca/Al of Pinus densiflora tree rings in estimating historical precipitation pH[J]. Soils Sediments, 11(5): 709−721. doi: 10.1007/s11368-011-0355-2 CrossRef Google Scholar
[66]	Ladha J K, Tirol−Padre A, Reddy C K, Cassman K G, Verma S, Powlson D S, Kessel C V, Richter D B, Chakraborty D, Pathak H. 2016. Global nitrogen budgets in cereals: A 50−year assessment for maize, rice, and wheat production systems[J]. Scientific Reports, 6(1): 19355 doi: 10.1038/srep19355 CrossRef Google Scholar
[67]	Lai T V, Farquharson R, Denton M D. 2019. High soil temperatures alter the rates of nitrification, denitrification and associated N₂O emissions[J]. Journal of Soils and Sediments, 19(5): 2176−2189. doi: 10.1007/s11368-018-02238-7 CrossRef Google Scholar
[68]	Lang M, Li P, Ti C, Zhu S, Yan X, Chang S X. 2019. Soil gross nitrogen transformations are related to land−uses in two agroforestry systems[J]. Ecological Engineering, 127: 431−439. doi: 10.1016/j.ecoleng.2018.12.022 CrossRef Google Scholar
[69]	Lehmann M F. Email Author, Reichert P, Bernasconi S M, Barbieri A, McKenzie J A. 2003. Modelling nitrogen and oxygen isotope fractionation during denitrification in a lacustrine redox−transition zone[J]. Geochimica et Cosmochimica Acta, 67(14): 2529−2542. doi: 10.1016/S0016-7037(03)00085-1 CrossRef Google Scholar
[70]	Lewicka−Szczebak D, Well R, Koster J R , Fuß R, Senbayram M, Dittert K, Flessa H. 2014. Experimental determinations of isotopic fractionation factors associated with N₂O production and reduction during denitrification in soils[J]. Geochimica et Cosmochimica Acta, 134(1): 55−73. Google Scholar
[71]	Li C, Jiang Y B, Guo X Y, Cao Y, Ji H B. 2014. Multi−isotope (¹⁵N, ¹⁸O and ¹³C) indicators of sources and fate of nitrate in the upper stream of Chaobai River, Beijing, China[J]. Environmental Sciences: Processes and Impacts, 16(11): 2644−2655. doi: 10.1039/C4EM00338A CrossRef Google Scholar
[72]	Li Siliang, Liu Congqiang, Xiao Huayun. 2002. A review of studies on microbial action and isotope fractionation in nitrogen cycle in surface environment[J]. Geology−Geochemistry, 30(4): 40−45 (in Chinese with English abstract). Google Scholar
[73]	Li S, Gurmesa G A, Zhu W. 2019. Fate of atmospherically deposited NH₄⁺ and NO₃⁻ in two temperate forests in China: Temporal pattern and redistribution[J]. Ecological Applications: A Publication of the Ecological Society of America, 29(6): e01920. doi: 10.1002/eap.1920 CrossRef Google Scholar
[74]	Li Zhaolei, Zeng Zhaoqi, Tian Dashuan, Wang Jinsong, Wang Bingxue, Chen Han Y. H, Quan Quan, Chen Weinan, Yang Jilin, Meng Cheng, Wang Yi, Niu Shuli. 2020. Global variations and controlling factors of soil nitrogen turnover rate[J]. Earth−Science Reviews, 207: 103250. doi: 10.1016/j.earscirev.2020.103250 CrossRef Google Scholar
[75]	Liao H K, Li Y Y, Yao H Y. 2018. Fertilization with inorganic and organic nutrients changes diazotroph community composition and N−fixation rates[J]. Soils Sediments, 18(3): 1076−1086. doi: 10.1007/s11368-017-1836-8 CrossRef Google Scholar
[76]	Lin C Y, Wang Y X, Liu M H, Li Q, Xiao W F, Song X Z. 2020. Effects of nitrogen deposition and phosphorus addition on arbuscular mycorrhizal fungi of Chinese fir (Cunninghamia lanceolate)[J]. Scientific Reports, 10(1): 1−8. doi: 10.1038/s41598-019-56847-4 CrossRef Google Scholar
[77]	Lin Wei, Fang Fuli, Zhang Wei, Ding Junjun, Li Yuzhong, Xu Chunying, Li Qiaozhen. 2017. A review on development of stable isotope technique in the studies of N₂O formation mechanism[J]. Chinese Journal of Applied Ecology, 28(7): 2344−2352 (in Chinese with English abstract). Google Scholar
[78]	Liu D W, Zhu W X, Wang X B, Pan P, Wang C, Xi D, Bai E, Wang S, Han X G, Fang Y T. 2017. Abiotic versus biotic controls on soil nitrogen cycling in drylands along a 3200 km transect[J]. Biogeosciences Discussions, (6): 1−26. Google Scholar
[79]	Liu Junzheng. 2019. Soil Nitrogen Cycling Rate in Poyang Lake Wetland Under Different Drought Conditions[D]. Nanchang: Jiangxi Normal University, 1−64 (in Chinese with English abstract). Google Scholar
[80]	Liu Q Y, Wang H M, Xu X L. 2020. Root nitrogen acquisition strategy of trees and understory species in a subtropical pine plantation in southern China[J]. European Journal of Forest Research, 139(5): 791−804. doi: 10.1007/s10342-020-01284-6 CrossRef Google Scholar
[81]	Liu R, Hu H W, Suter H. 2016a. Nitrification is a primary driver of nitrous oxide production in laboratory microcosms from different land−use soils[J]. Frontiers in Microbiology, 7: 1373. Google Scholar
[82]	Liu X J, Zhang Y, Han W X, Tang A H, Shen J L, Cui Z L, Vitousek P, Erisman J W, Goulding K, Christie P, Fangmeier A, Zhang F S. 2013. Enhanced nitrogen deposition over China[J]. Nature, 494(7438): 459−462. doi: 10.1038/nature11917 CrossRef Google Scholar
[83]	Liu Y, He N P, Wen X F, Yu G R, Gao Y, Jia Y L. 2016b. Patterns and regulating mechanisms of soil nitrogen mineralization and temperature sensitivity in Chinese terrestrial ecosystems[J]. Agriculture Ecosystems & Environment, 215: 40−46. Google Scholar
[84]	Lu M Z, Cheng S L, Fang H L, Xu M, Yang Y, Li Y N, Zhang J B, Müller C. 2021. Organic nitrogen addition causes decoupling of microbial nitrogen cycles by stimulating gross nitrogen transformation in a temperate forest soil[J]. Geoderma, 385: 114886. doi: 10.1016/j.geoderma.2020.114886 CrossRef Google Scholar
[85]	Luo D H, Dong H, Luo H Y, Xian Y P, Wan J, Guo X D, Wu Y L. 2015b. The application of stable isotope ratio analysis to determine the geographical origin of wheat[J]. Food Chemistry, 174: 197−201. doi: 10.1016/j.foodchem.2014.11.006 CrossRef Google Scholar
[86]	Luo T, Ouyang X Q, Yang L T, Li Y R, Song X P, Zhang G M , Gao Y J, Duan W X. 2015a. Benefit to growth of micropropagated sugarcane plants following inoculation with Klebsiella plantica[J]. International Sugar Journal, 117(1400): 564−568. Google Scholar
[87]	Ma J, Bei Q C, Wang X J, Lan P, Liu G, Lin X W, Liu Q, Lin Z B, Liu B J, Zhang Y H. 2019. Impacts of Mo application on biological nitrogen fixation and diazotrophic communities in a flooded rice−soil system[J]. Science of the Total Environment, 649: 686−694. doi: 10.1016/j.scitotenv.2018.08.318 CrossRef Google Scholar
[88]	Ma Xiuyan, Jiang Lei, Song Yanyu, Sun Li, Song Changchun, Hou Aixin, Gao Jinli, Du Yu. 2021. Effects of temperature and moisture changes on functional gene abundance of soil nitrogen cycle in permafrost peatland[J]. Acta Ecologica Sinica, 41(17): 6707−6717 (in Chinese with English abstract). Google Scholar
[89]	Mao Chao, Qi Lianghua. 2015. Research advances on nitrogen transformation and cycling in forest soil[J]. World Forestry Research, 28(2): 8−13 (in Chinese with English abstract). Google Scholar
[90]	Martin T S, Casciotti K L. 2016. Nitrogen and oxygen isotopic fractionation during microbial nitrite reduction[J]. Limnology & Oceanography, 61(3): 1134−1143. Google Scholar
[91]	Martínez−Espinosa C, Sauvage S, Bitar A A, Green P A, Vörösmarty C J, Sánchez−Pérez J M. 2021. Denitrification in wetlands: A review towards a quantification at global scale[J]. Science of the Total Environment, 754: 142398. doi: 10.1016/j.scitotenv.2020.142398 CrossRef Google Scholar
[92]	Martins D S, Reis V M, Schultz N, Bruno J R A, Urquiaga S, Pereira W, Sousa S J, Boddey M R. 2020. Both the contribution of soil nitrogen and of biological N₂ fixation to sugarcane can increase with the inoculation of diazotrophic bacteria[J]. Plant and Soil, 454(1): 155−169. Google Scholar
[93]	Mason R E, Craine J M, Lany N K, Jonard M, Ollinger S V, Groffman P M, Fulweiler R W, Angerer J, Read Q D, Reich P B, Templer P H, Elmore A J. 2022. Evidence, causes, and consequences of declining nitrogen availability in terrestrial ecosystems[J]. Science, 376(6590): 261. Google Scholar
[94]	McLauchlan K K, Ferguson C J, Wilson I E, Ocheltree T W, Craine M J. 2010. Thirteen decades of foliar isotopes indicate declining nitrogen availability in central North American grasslands[J]. The New Phytologist, 187(4): 1135−1145. doi: 10.1111/j.1469-8137.2010.03322.x CrossRef Google Scholar
[95]	Miller A E, Bowman W D, Suding K N. 2007. Plant uptake of inorganic and organic nitrogen: Neighbor identity matters[J]. Ecology, 88(7): 1832−1840. doi: 10.1890/06-0946.1 CrossRef Google Scholar
[96]	Nardi P, Akutsu M, Pariasca−Tanaka J, Wissuwa M. 2013. Effect of methyl 3−4−hydroxyphenyl propionate, a Sorghum root exudate, on N dynamic, potential nitrification activity and abundance of ammonia–oxidizing bacteria and archaea[J]. Plant and Soil, 367(1/2): 627−637. Google Scholar
[97]	Nordin A, Högberg P, Näsholm T. 2001. Soil nitrogen form and plant nitrogen uptake along a boreal forest productivity gradient[J]. Oecologia, 129(1): 125−132. doi: 10.1007/s004420100698 CrossRef Google Scholar
[98]	Oulimata D, Dahl K E, Madjiguene D A, Rostgaard N L, Vlastimil N, Diaminatou S, Holst L K, Kehlet H J, Anders R. 2022. Leaf morphology and stable isotope ratios of carbon and nitrogen in Acacia senegal (L. ) Wild trees vary with climate at the geographic origin and ploidy level[J]. Trees, 36(1): 295−312. doi: 10.1007/s00468-021-02206-8 CrossRef Google Scholar
[99]	Pan B B, ZhangY S, Xia L L, Lam S K, Hu H W, Chen D L. 2022. Nitrous oxide production pathways in Australian forest soils[J]. Geoderma, 420: 115871. doi: 10.1016/j.geoderma.2022.115871 CrossRef Google Scholar
[100]	Pan Y P, Tian S L, Liu D W, Fang Y T, Zhu X Y, Zhang Q, Zheng B, Michalski G, Wang Y S. 2016. Fossil fuel combustion−related emissions dominate atmospheric ammonia sources during severe haze episodes: Evidence from ¹⁵N−stable isotope in size−resolved aerosol ammonium[J]. Environmental Science & Technology, 50(15): 8049−56. Google Scholar
[101]	Park H J, Baek N, Lim S S, Jeong Y G, Seo B S, Kwak J H, Lee S M, Yun S I, Kim H Y, Muhammad A. 2023. Coupling of δ¹³C and δ¹⁵N to understand soil organic matter sources and C and N cycling under different land−uses and management: A review and data analysis[J]. Biology and Fertility of Soils, 59(5): 487−499. doi: 10.1007/s00374-022-01668-3 CrossRef Google Scholar
[102]	Park S, Croteau P, Boering K A, Etheridge D M, Ferretti D, Fraser P J, Kim K R, Krummel P B, Langenfelds R L, van Ommen T D, Steele L P, Trudinger C M. 2012. Trends and seasonal cycles in the isotopic composition of nitrous oxide since 1940[J]. Nature Geoscience, 5(4): 261−265. doi: 10.1038/ngeo1421 CrossRef Google Scholar
[103]	Parnell A C, Inger R, Bearhop S, Jackson A L. 2010. Source partitioning using stable isotopes: Coping with too much variation[J]. PLoS One, 5(3): 1−5. Google Scholar
[104]	Phillips D L, Koch P L. 2002. Incorporating concentration dependence in stable isotope mixing models[J]. Oecologia, 130(1): 114−125. doi: 10.1007/s004420100786 CrossRef Google Scholar
[105]	Rittenberg D, Keston A S, Rosebury F, Schoenheimer R. 1939. Studies in protein metabolism Ⅱ The determinatson of nitro gen isotopes in organic compound[J]. The Jounal of Biological Chemistry, 127(1): 291−299. doi: 10.1016/S0021-9258(18)73841-6 CrossRef Google Scholar
[106]	Rohe L, Well R, Lewicka−Szczebak D. 2017. Use of oxygen isotopes to differentiate between nitrous oxide produced by fungi or bacteria during denitrification[J]. Rapid Communications in Mass Spectrometry, 31(16): 1297−1312. doi: 10.1002/rcm.7909 CrossRef Google Scholar
[107]	Rossiter−Rachor N A, Setterfield S A, Douglas M M, HutleyL B, Cook G D, Schmidt S. 2009. Invasive Andropogon gayanus (gamba grass) is an ecosystem transformer of nitrogen relations in Australian savanna[J]. Ecological Applications, 19(6): 1546−1560. doi: 10.1890/08-0265.1 CrossRef Google Scholar
[108]	Rui Y C, Wang S P, Xu Z H, Wang Y , Chen, C R, Zhou X Q, Kang X M, Lu S B, Hu Y G, Lin Q Y, Luo C Y. 2011. Warming and grazing afect soil labile carbon and nitrogen pools diferently in an alpine meadow of the Qinghai−Tibet Plateau in China[J]. Soils Sediments, 11(6): 903−914. Google Scholar
[109]	Sankoh A A, Derkyi N S A, Frazer−williams R A D, Laar C, Kamara I. 2022. A review on the application of isotopic techniques to trace groundwater pollution sources within developing countries[J]. Water, 14(35): 35. Google Scholar
[110]	Schwede D B, Simpson D, Tan J, Fu J S, Dentener F, Du E, deVries W. 2018. Spatial variation of modelled total, dry and wet nitrogen deposition to forests at global scale[J]. Environmental Pollution, 243: 1287−1301. doi: 10.1016/j.envpol.2018.09.084 CrossRef Google Scholar
[111]	Shen J X, Aubrey L Z, Mark W C. 2022. Nitrogen cycling and biosignatures in a hyperarid mars analog environment[J]. Astrobiology, 22(2): 127−142. doi: 10.1089/ast.2021.0012 CrossRef Google Scholar
[112]	Silva A, Franzini V I, Piccolla C D, Muraoka T. 2017. Molybdenum supply and biological fixation of nitrogen by two Brazilian common bean cultivars[J]. Revista Brasileira de Engenharia Agrícola e Ambiental, 21(2): 100−105. Google Scholar
[113]	Skjemstad J O, Taylor J A, Janik L J, Marvanek S P. 1999. Soil organic carbon dynamics under long−term sugarcane monoculture[J]. Australian Journal of Soil Research, 37: 151−164. doi: 10.1071/S98051 CrossRef Google Scholar
[114]	Song W, Liu X Y, Liu C Q. 2021. New constraints on isotopic effects and major sources of nitrate in atmospheric particulates by combining δ¹⁵N and Δ¹⁷O signatures[J]. Journal of Geophysical Research: Atmospheres, 126(16): 2169−897X. Google Scholar
[115]	Søvik A K, Mørkved P T. 2008. Use of stable nitrogen isotope fractionation to estimate denitrification in small constructed wetlands treating agricultural runoff[J]. Science of the Total Environment, 392(1): 157−165. doi: 10.1016/j.scitotenv.2007.11.014 CrossRef Google Scholar
[116]	Su C X, Kang R H, Zhu W X, Huang W T, Song L L, Wang A, Liu D W, Quan Z, Zhu F F, Fu P Q, Fang Y T. 2020. δ¹⁵N of nitric oxide produced under aerobic or anaerobic conditions from seven soils and their associated N isotope fractionations[J]. Journal of Geophysical Research: Biogeosciences, 125(9): 1−18. Google Scholar
[117]	Suzuki Y. 2021. Achieving Food Authenticity and Traceability using an Analytical Method Focusing on Stable Isotope Analysis[J]. Analytical sciences: The international journal of the Japan Society for Analytical Chemistry, 37(1): 189−199. Google Scholar
[118]	Tao K, Kelly S, Radutoiu S. 2019. Microbial associations enabling nitrogen acquisition in plants[J]. Current Opinion in Microbiology, 49: 83−89. doi: 10.1016/j.mib.2019.10.005 CrossRef Google Scholar
[119]	Taousa F, Amenzoua N, Marah H, Maia R, Maguas C, Bahmad L, Kelly S. 2020. Stable isotope ratio analysis as a new tool to trace the geographical origin of Argan oils in Morocco[J]. Forensic Chemistry, 17: 2468−1709. Google Scholar
[120]	Templer P H, Mack M C, Chapin III F S, Christenson L M, Compton J E, Crook H D, Currie W S, Curtis C J, Dail D B, D'Antonio C M, Emmet B A, Epstein H E, Goodale C L, Gundersen P, Hobble S E, Holland K, Hooper D U, Hungate B A, Lamontagne S, Nadelhoffer K J. 2012. Sinks for nitrogen inputs in terrestrial ecosystems: A meta−analysis of ¹⁵N tracer field studies[J]. Ecology, 93(8): 1816−1829. doi: 10.1890/11-1146.1 CrossRef Google Scholar
[121]	Tharayil N, Alpert P, Bhowmik P, Gerard P. 2013. Phenolic inputs by invasive species could impart seasonal variations in nitrogen[J]. Soil Biology and Biochemistry, 57: 858−867. doi: 10.1016/j.soilbio.2012.09.016 CrossRef Google Scholar
[122]	Thorpe A S, Callaway R M. 2011. Biogeographic differences in the effects of Centaurea stoebe on the soil nitrogen cycle: Novel weapons and soil microbes[J]. Biological Invasions, 13(6): 1435−1445. doi: 10.1007/s10530-010-9902-9 CrossRef Google Scholar
[123]	Tian H Q, Xu R T, Canadell J G, Thompson R L, Winiwarter W, Suntharalingam P, Davidson E A, Ciais P, Jackson R B, Janssens−Maenhout G, Prather M J, Regnier P, Pan N Q, Pan S F, Peters G P, Shi H, Tubiello F N, Zaehle S, Zhou F, Arneth A, Battaglia G, Berthet S, Bopp L, Bouwman A F, Buitenhuis E T, Chang J F, Chipperfield M P, Dangal S R S, Dlugokencky E, Elkins J W, Eyre B D, Fu B J, Hall B, Ito A, Joos F, Krummel P B, Landolfi A, Laruelle G G, Lauerwald R, Li W, Lienert S, Maavara T, MacLeod M, Millet D B, Olin S, Patra P K, Prinn R G, Raymond P A, Ruiz D J, van der Werf G R, Vuichard N, Wang J J, Weiss R F, Wells K C, Wilson C, Yang J, Yao Y Z. 2020. A comprehensive quantification of global nitrous oxide sources and sinks[J]. Nature, 586(7828): 248. doi: 10.1038/s41586-020-2780-0 CrossRef Google Scholar
[124]	Treibergs L A, Granger J. 2017. Enzyme level N and O isotope effects of assimilatory and dissimilatory nitrate reduction[J]. Limnology & Oceanography, 62(1): 272−288. Google Scholar
[125]	Van Deynze A, Zamora P, Pierre−Marc Delaux. 2018. Nitrogen fixation in a landrace of maize is supported by a mucilage−associated diazotrophic microbiota[J]. PLOS Biology, 16(8): e2006352. doi: 10.1371/journal.pbio.2006352 CrossRef Google Scholar
[126]	Wang A, Chen D X, Phillips O L, Gundersen P, Zhou X L, Gurmesa G A, Li S L, Zhu W X, Hobbie E A, Wang X Y, Fang Y T. 2021. Dynamics and multi−annual fate of atmospherically deposited nitrogen in montane tropical forests[J]. Global Change Biology 27(10): 2076−2087. Google Scholar
[127]	Wang A, Fang Y T, Chen D X, Phillips O, Koba K. 2018. High nitrogen isotope fractionation of nitrate during denitrification in four forest soils and its implications for denitrification rate estimates[J]. Science of the Total Environment, 633(1): 1078−1088. Google Scholar
[128]	Wang H, Yan Z F, Ju X T, Song X T, Zhang J B, Li S L, Barker X Z. 2023. Quantifying nitrous oxide production rates from nitrification and denitrification under various moisture conditions in agricultural soils: Laboratory study and literature synthesis[J]. Frontiers in Microbiology, 13: 1110151. doi: 10.3389/fmicb.2022.1110151 CrossRef Google Scholar
[129]	Wang J, Cheng Y, Zhang J B, Müeller C, Cai Z C. 2016. Soil gross nitrogen transformations along a secondary succession transect in the north subtropical forest ecosystem of southwest China[J]. Geoderma, 280(1): 88−95. Google Scholar
[130]	Wang J, Zhu B, Zhang J B, Müller C, Cai Z C. 2015. Mechanisms of soil N dynamics following long−term application of organic fertilizers to subtropical rain−fed purple soil in China[J]. Soil Biology & Biochemistry, 91: 222−231. Google Scholar
[131]	Wang Keyi, Liu Xiaohong, Zeng Xiaomin, Xu Guobao, Zhang Lingnan, Li Chunyue. 2021. Stable nitrogen isotope in tree rings: Progresses, problems and prospects[J]. Acta Geographica Sinica, 76(5): 1193−1205 (in Chinese with English abstract). Google Scholar
[132]	Wang L, Macko S A. 2011. Constrained preferences in nitrogen uptake across plant species and environments[J]. Plant, Cell & Environment, 34(3): 525−534. Google Scholar
[133]	Wang Liming, Wu Hao, Lin Guanghui. 2015. Progresses in applications of stable isotope technology to determining geographical origins of traditional Chinese medicines[J]. Journal of Isotopes, 28(4): 225−232 (in Chinese with English abstract). Google Scholar
[134]	Waser N A D, Harrison P J, Nielsen B, Calvert S E, Turpin D H. 1998. Nitrogen isotope fractionation during the uptake and assimilation of nitrate, nitrite, ammonium, and urea by a marine diatom[J]. Limnology and Oceanography, 43(2): 215−224. doi: 10.4319/lo.1998.43.2.0215 CrossRef Google Scholar
[135]	Well R, Eschenbach W, Flessa H, Heide C V D, Weymann D. 2012. Are dual isotope and isotopomer ratios of N₂O useful indicators for N₂O turnover during denitrification in nitrate−contaminated aquifers?[J]. Geochimica et Cosmochimica Acta, 90(1): 265−282. Google Scholar
[136]	Wells N S, Baisden W T, Clough T J. 2015. Ammonia volatilization is not the dominant factor in determining the soil nitrate isotopic composition of pasture systems[J]. Agriculture Ecosystems & Environment, 199: 290−300. Google Scholar
[137]	Widory D, Petelet−Giraud E, Brenot A, Bronders J, Tirez K, Boeckx P. 2013. Improving the management of nitrate pollution in water by the use of isotope monitoring: The δ¹⁵N, δ¹⁸O and δ¹¹B triptych[J]. Isotopes in Environmental & Health Studies, 49(1): 29−47. Google Scholar
[138]	Wrage−Mönnig N, Horn M A, Well R, Müller C, Velthof G, Oenema O. 2018. The role of nitrifier denitrification in the production of nitrous oxide revisited[J]. Soil Biology and Biochemistry, 123: A3−A16. doi: 10.1016/j.soilbio.2018.03.020 CrossRef Google Scholar
[139]	Wu Y L, Luo D H, Dong H, Wan J, Luo H Y, Xian Y P, Guo X D, Qin F F, Han W Q, Wang L, Wang B. 2015. Geographical origin of cereal grains based on element analyser−stable isotope ratio mass spectrometry (EA−SIRMS)[J]. Food Chemistry, 174: 553−557. doi: 10.1016/j.foodchem.2014.11.096 CrossRef Google Scholar
[140]	Xie Xianjun. 2019. Principles and Applications of Environmental Isotopes[M]. Beijing: Science Press (in Chinese). Google Scholar
[141]	Xiu L Q, Zhang W M, Wu D, Sun Y Y, Zhang H G, Gu W Q, Wang Y N, Meng J, Chen W F. 2021. Biochar can improve biological nitrogen fixation by altering the root growth strategy of soybean in Albic soil[J]. Science of the Total Environment, 773: 144564. doi: 10.1016/j.scitotenv.2020.144564 CrossRef Google Scholar
[142]	Xue D M, Botte J, De Baets B, Accoe F, Nestler A, Taylor P, Van Cleemput O, Berglund M, Boeckx P. 2009. Present limitations and future prospects of stable isotope methods for nitrate source identification in surface−and groundwater[J]. Water Research, 43(5): 1159−1170. doi: 10.1016/j.watres.2008.12.048 CrossRef Google Scholar
[143]	Yang L P, Han J P, Xue J L, Zeng L Z, Shi J C, Wu L S, Jiang Y H. 2013. Nitratesource apportionment in a subtropical watershed using Bayesian model[J]. Science of the Total Environment, 463−464(13): 340−347. Google Scholar
[144]	Yang W H, McDowell A C, Brooks P D, Silver W L. 2014. New high precision approach for measuring ¹⁵N−N₂ gas fluxes from terrestrial ecosystems[J]. Soil Biology & Biochemistry, 69: 234−241. Google Scholar
[145]	Yao Fanyun, Zhu Biao, Du Enzai. 2015. Use of ¹⁵N natural abundance in nitrogen cycling of terrestrial ecosystems[J]. Chinese Journal of Plant Ecology, 36(4): 346−352 (in Chinese with English abstract). Google Scholar
[146]	You Chongshao, Li Yugui, Liu Donglai, Hu Yimin, Ling Mingde. 1965. Mass spectrometry analysis of ¹⁵N in biological samples. Atomic Energy, 6: 535−542 (in Chinese). Google Scholar
[147]	Yun S I, Ro S I, Choi W J, Han G H. 2011. Interpreting the temperature−induced response of ammonia oxidizing microorganisms in soil using nitrogen isotope fractionation[J]. Journal of Soils & Sediments, 11(7): 1253−1261. Google Scholar
[148]	Yun S I, Ro S I. 2014. Can nitrogen isotope fractionation reveal ammonia oxidation responses to varying soil moisture?[J]. Soil Biology & Biochemistry, 76: 136−139. Google Scholar
[149]	Zan Qilin, Lai Xiaoming, Zhu Qing, Wang Weiguang, Li Liuyang, Liu Ya. 2022. Study on factors Influencing spatial variation of soil ¹⁵N Natural Abundance on Global Scale[J]. Soils, 54(5): 920−927 (in Chinese). Google Scholar
[150]	Zendehbad M, Cepuder P, Loiskandl W, Stumpp C. 2019. Source identification of nitrate contamination in the urban aquifer of Mashhad, Iran[J]. Journal of Hydrology: Regional Studies, 25: 100618. doi: 10.1016/j.ejrh.2019.100618 CrossRef Google Scholar
[151]	Zhang J B, Müller C, Cai Z C. 2015b. Heterotrophic nitrification of organic N and its contribution to nitrous oxide emissions in soils[J]. Soil Biology & Biochemistry, 84: 199−209. Google Scholar
[152]	Zhang J B, Wang L, Zhao W, Hu H F, Feng X J, Müller C, Cai Z C. 2016a. Soil gross nitrogen transformations along the Northeast China Transect (NECT) and their response to simulated rainfall events[J]. Scientific Reports, 6(3): 22830−22830. Google Scholar
[153]	Zhang J, Cai Z, Müller C. 2018. Terrestrial N cycling associated with climate and plant specific N preferences: A review[J]. European Journal of Soil Science, 69(3): 488−501. Google Scholar
[154]	Zhang Jinbo, Dai Shenyan, Wen Teng, Cai Zucong. 2022. Principle and Application of Stable Isotope Tracer of Carbon and Nitrogen[M]. Beijing: Science Press (in Chinese). Google Scholar
[155]	Zhang L Y, Zhang M L, Huang S Y, Li L J, Gao Q, Wang Y, Zhang S Q, Huang S M, Yuan L, Wen Y C, Liu K L, Yu X C, Li D C, Zhang L, Xu X P, Wei H L, He P, Zhou W, Philippot L, Ai C. 2022. A highly conserved core bacterial microbiota with nitrogen−fixation capacity inhabits the xylem sap in maize plants[J]. Nature Communications, 13(1): 1−13. doi: 10.1038/s41467-021-27699-2 CrossRef Google Scholar
[156]	Zhang W, Li Y Z, Xu C Y, Li Q Z, Lin W. 2016b. Isotope signatures of N₂O emitted from vegetable soil: Ammonia oxidation drives N₂O production in NH₄⁺−fertilized soil of North China[J]. Scientific Reports, 6: 29257. doi: 10.1038/srep29257 CrossRef Google Scholar
[157]	Zhang Y S, Zhang J B, Zhu T B, Müller C, Cai Z C. 2015a. Effect of orchard age on soil nitrogen transformation in subtropical China and implications[J]. Acta Scientiae Circumstantiae, (8): 10−19. Google Scholar
[158]	Zhang Y, Li F D, Zhang Q Y, Li J, Liu Q. 2014. Tracing nitrate pollution sources and transformation in surface and ground−waters using environmental isotopes[J]. The Science of the Total Environment, 490: 213−222. doi: 10.1016/j.scitotenv.2014.05.004 CrossRef Google Scholar
[159]	Zhang Y, Shi P, Song J X, Li Q. 2019. Application of nitrogen and oxygen isotopes for source and fate identification of nitrate pollution in surface water: A review[J]. Applied Sciences, 9(1): 18. Google Scholar
[160]	Zhang Y, Zhao J, Huang X Q, Cheng Y, Cai Z C, Zhang J B, Müller C. 2021. Microbial pathways account for the pH effect on soil N₂O production[J]. European Journal of Soil Biology, 106: 103337. doi: 10.1016/j.ejsobi.2021.103337 CrossRef Google Scholar
[161]	Zhang Y, Zhao W, Zhang J B, Cai Z C. 2017. N₂O production pathways relate to land use type in acidic soils in subtropical China[J]. Journal of Soil & Sediments, 17(2): 306−314. Google Scholar
[162]	Zhang Yanhui, Hu Tianlong, Wang Hui, Jin Haiyang, Liu Benjuan, Liu Hongtao, Liu Qi, Lin Zhibin, Lin Xingwu, Xie Zubin. 2021. Effects of rice planting on nitrogen fixation amount and activity in paddy field using ¹⁵N₂ direct labeling method[J]. Soils, 53(4): 739−745 (in Chinese with English abstract). Google Scholar
[163]	Zhang Zhijun, Qin Shuping, Yuan Haijing, Zhang Yuming, Hu Chunsheng. 2018. Advance in soil dinitrogen emission[J]. Chinese Journal of Eco−Agriculture, 26(2): 182−189 (in Chinese with English abstract). Google Scholar
[164]	Zheng Yongfei, Chen Jiangfeng. 2000. Stable Isotope Geochemistry [M]. Beijing: Science Press (in Chinese). Google Scholar
[165]	Zhou J, Shao G D, Kumar A, Shi L, Kuzyakov Y, Pausch J. 2022. Carbon fuxes within tree−crop−grass agroforestry system: ¹³C labeling and tracing[J]. Biology and Fertility of Soils, 58(7): 733−743. doi: 10.1007/s00374-022-01659-4 CrossRef Google Scholar
[166]	Zhou M X, Yan G Y, Xing Y J, Chen F, Zhang X, Wang J Y, Zhang J H, Dai G H, Zheng X B, Sun W J. 2019. Nitrogen deposition and decreased precipitation does not change total nitrogen uptake in a temperate forest[J]. Science of the Total Environment, 651(1): 32−41. Google Scholar
[167]	Zhu F F, Dai L M, Hobbie E A. 2019. Uptake patterns of glycine, ammonium, and nitrate differ among four common tree species of northeast china[J]. Frontiers in Plant Science, 10: 799. doi: 10.3389/fpls.2019.00799 CrossRef Google Scholar
[168]	Zong Yi, Huang Qiaoqiao, Li Xiaoxia, Fan Zhiwei, Shen Yide. 2015. Spread and explosion of Merremia boisiana on physical and chemical properties and enzyme activity in soil ecosystem[J]. Guangdong Agricultural Sciences, 42(1): 42−45 (in Chinese with English abstract). Google Scholar
[169]	曹亚澄, 张金波, 温腾. 2018. 稳定同位素示踪技术与质谱分析在土壤、生态、环境研究中的应用[M]. 北京: 科学出版社. Google Scholar
[170]	冯晓敏, 高翔, 臧华栋, 胡跃高, 任长忠, 郝志萍, 吕慧卿, 曾昭海. 2023. 燕麦−绿豆间作效应及氮素转移特性[J]. 植物学报, 58(1): 122−131. doi: 10.11983/CBB22176 CrossRef Google Scholar
[171]	黄乔乔, 许慧, 范志伟, 侯玉平. 2013. 火炬树入侵黑松幼林过程中对土壤化学性质的影响[J]. 生态环境学报, 22(7): 1119−1123. doi: 10.3969/j.issn.1674-5906.2013.07.005 CrossRef Google Scholar
[172]	李思亮, 刘丛强, 肖化云. 2002. 地表环境氮循环过程中微生物作用及同位素分馏研究综述[J]. 地质地球化学, 30(4): 40−45. Google Scholar
[173]	林伟, 房福力, 张薇, 丁军军, 李玉中, 徐春英, 李巧珍. 2017. 稳定同位素技术在土壤N₂O溯源研究中的应用[J]. 应用生态学报, 28(7): 2344−2352. Google Scholar
[174]	刘君政. 2019. 不同干旱条件下鄱阳湖湿地土壤氮循环速率[D]. 南昌: 江西师范大学, 1−64. Google Scholar
[175]	马秀艳, 蒋磊, 宋艳宇, 孙丽, 宋长春, 侯爱新, 高晋丽, 杜宇. 2021. 温度和水分变化对冻土区泥炭地土壤氮循环功能基因丰度的影响[J]. 生态学报, 41(17): 6707−6717. Google Scholar
[176]	毛超, 漆良华. 2015. 森林土壤氮转化与循环研究进展[J]. 世界林业研究, 28(2): 8−13 Google Scholar
[177]	王可逸, 刘晓宏, 曾小敏, 徐国保, 张凌楠, 李春越. 2021. 树轮稳定氮同位素记录的进展与展望[J]. 地理学报, 76(5): 1193−1205. doi: 10.11821/dlxb202105011 CrossRef Google Scholar
[178]	王黎明, 吴浩, 林光辉. 2015. 稳定同位素技术在中药产地溯源方面的应用研究进展[J]. 同位素, 28(4): 225−232. doi: 10.7538/tws.2015.28.04.0225 CrossRef Google Scholar
[179]	谢先军. 2019. 环境同位素原理与应用[M]. 北京: 科学出版社. Google Scholar
[180]	姚凡云, 朱彪, 杜恩在. 2015. ¹⁵N自然丰度法在陆地生态系统氮循环研究中的应用[J]. 植物生态学报, 36(4): 346−352. Google Scholar
[181]	尤崇杓, 李玉桂, 刘东来, 胡铁民, 凌明德. 1965. 生物样本中¹⁵N的质谱分析[J]. 原子能, 6: 535−542. Google Scholar
[182]	昝麒麟, 赖晓明, 朱青, 王卫光, 李柳阳, 刘亚. 2022. 全球尺度上土壤¹⁵N自然丰度空间变化的影响因素[J]. 土壤, 54(5): 920−927. Google Scholar
[183]	张金波, 戴沈燕, 温腾, 蔡祖聪. 2022. 碳氮稳定同位素示踪原理与应用[M]. 北京: 科学出版社. Google Scholar
[184]	张燕辉, 胡天龙, 王慧, 靳海洋, 刘本娟, 刘红涛, 刘琦, 林志斌, 蔺兴武, 谢祖彬. 2021. 利用¹⁵N₂直接标记法研究水稻种植对稻田固氮量和固氮活性的影响[J]. 土壤, 53(4): 739−745. Google Scholar
[185]	张志君, 秦树平, 袁海静, 张玉铭, 胡春胜. 2018. 土壤氮气排放研究进展[J]. 中国生态农业学报, 26(2): 182−189. Google Scholar
[186]	郑永飞, 陈江峰. 2000. 稳定同位素地球化学[M]. 北京: 科学出版社. Google Scholar
[187]	纵熠, 黄乔乔, 李晓霞, 范志伟, 沈奕德. 2015. 金钟藤蔓延成灾对土壤理化性质及土壤酶活性的影响[J]. 广东农业科学, 42(1): 42−45. doi: 10.3969/j.issn.1004-874X.2015.01.010 CrossRef Google Scholar