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nitrogen transfer between N_2-fixing plant and non-N_2-fixing plant

Journal of Forestry Research 2000年第2期11卷 75-80页

作者：蒋三乃翟明普 Beijing Forestry University College of Resource and Environment Beijing P.R. China (GRID:grid.66741.32)

The transfer mechanisms. calculating methods and ecological significance of nitrogen transfer between legumes and non-legumes are briefly reviewed. There are three pathways 0f nitrogen transf6r from legumes to neighboring non-legumes: (1) the nitrogen pass in soluble form from the donor legume root into the soil solution, move by diffusion or/and mass flow to the receiver root and be taken up by the latter, (2) nitrogen pass into the soil solution as before, be taken up and transported by mycorrhizal hyphae attached to the receiver roots,(3) if mycorrhizal hyphae form connections (bridges) between the two root systems, the nitrogen could pass into the fungus within the donor root and be transported into the receiver root without ever being in the soil solution. The mechanisms of nitrogen transfer between N2-fixing plants and non-N2-fixing plants are reviewed in terms of indirect and direct pathways. The indirect N-transfer process is related to the release of nitrogen from legumes(donor plants), the possible interaction of this nitrogen with soil, the decomposition and mineralization of legumes and tumover of nitrogen, the nitrogen absorbing and competing abilities of the legume and the non-legume (receiver plant). The direCt nitrogen transfer process is generally considered to be related to the nitrogen gradient and physiological imbalance between legumes and non-legumes, and when the donor legume lies in stressful stage (i.e. removal of shoots or attacked by insects), the nitrogen transfer can be improved significantly. Themethods of deterrnining nitrogen transfer (lndirect 15N-isotope. dilution method and direct 15N determination method) are evaluated, and their advantages and shortcomings are shown in this review.

关键词： nitrogen transfer N_2-fixing plant Non-N_2-fixing plant

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Spatial patterns nitrogen transfer models of ectomycorrhizal networks in a Mongolian scotch pine plantation

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Journal of Forestry Research 2018年第2期29卷 337-344页

作者： Yanbin Liu Hongmei Chen Pu Mou College of Life Science Beijing Normal UniversityBeijing 100875People’s Republic of China Institute of Forestry Science Heilongjiang Academy of ForestryHarbin 150081People’s Republic of China Institute of Biology University of LeipzigJohannisallee 2104103 LeipzigGermany State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing 100875People’s Republic of China

Ectomycorrhizal(EM)networks provide a variety of services to plants and ecosystems include nutrient uptake and transfer,seedling survival,internal cycling of nutrients,plant competition,and so *** deeply their structure and function in ecosystems,we investigated the spatial patterns and nitrogen(N)transfer of EM networks usingN labelling technique in a Mongolian scotch pine(Pinus sylvestris *** Litv.)plantation in Northeastern *** August 2011,four plots(20 × 20 m)were set up in the plantation.125 ml 5 at.%0.15 mol/LNHNOsolution was injected into soil at the center of each *** and 2,6,30 and 215 days after theN application,needles(current year)of each pine were sampled along four 12 m sampling *** total N andN concentrations were *** observed needle N andN concentrations increased significantly over time afterN application,up to 31 and0.42%,*** was no correlation between needle N concentration andN/N ratio(R2=0.40,n=5,P=0.156),while excess needle N concentration and excess needleN/N ratio were positively correlated across different time intervals(R~2=0.89,n=4,P\0.05),but deceased with time interval ***/N ratio increased with time,but it was not correlated with ***/N ratio was negative with distance before and 6th day and 30th day,positive with distance at 2nd day,but the trend was considerably weaker,their slop were close to *** results demonstrated that EM networks were ubiquitous and uniformly distributed in the Mongolian scotch pine plantation and a random *** found N transfer efficiency was very high,absorbed N by EM network was transferred as wide as possible,we observed N uptake of plant had strong bias forN andN,namely N *** the structure and function of EM networks in ecosystems may lead to a deeper understanding of ecological stability and evolution,and thus provide new theoretical approaches to improve conservation practices for the ma

关键词： Ectomycorrhizal networks Spatial patterns nitrogen transfer Mongolian scotch pine plantation Stable isotope 15N labelling

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Use of ^(15)N stable isotope to quantify nitrogen transfer between mycorrhizal plants

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Journal of Plant Ecology 2009年第3期2卷 107-118页

作者： Xinhua He Minggang Xu Guo Yu Qiu Jianbin Zhou School of Life Sciences Yunnan Normal UniversityKunmingYunnan 650092China School of Plant Biology(M084) University of Western AustraliaCrawleyWestern Australia 6009Australia Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory for Environmental and Urban Sciences Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China College of Resource and Environmental Sciences Northwest A&F UniversityYanglingShaanxi 712100China

Aims Mycorrhizas(fungal roots)play vital roles in plant nutrient acquisition,performance and productivity in terrestrial *** mycorrhizas(AM)and ectomycorrhizas(EM)are mostly important since soil nutrients,including NH+4,NO3 and phosphorus,are translocated from mycorrhizal fungi to *** species,genera and even families of plants could be interconnected by mycorrhizal mycelia to form common mycorrhizal networks(CMNs).The function of CMNs is to provide pathways for movement or transfer of nutrients from one plant to *** the past four decades,both ^(15)N external labeling or enrichment(usually expressed as atom%)and ^(15)N naturally occurring abundance(d^(15)N,&)techniques have been employed to trace the direction and magnitude of N transfer between plants,with their own advantages and *** Findings The heavier stable isotope ^(15)N is discriminated against 14N during biochemical,biogeochemical and physiological processes,due to a greater atomic *** general,non-N2-fixing plants had greater d^(15)N values than N2-fixing(;0&)*** d^(15)N often varied by 5 to 10&in the order:non-mycorrhizas/AMs>EMs>ericoid *** in d^(15)N(&)or ^(15)N(atom%)values could thus provide N transfer information between plants.A range of between 0 to 80%of one-way N transfer had been observed from N2-fixing mycorrhizal to non-N2-fixing mycorrhizal plants,but generally less than or around 10%in the reverse ***-to-plant N transfer may provide practical implications for plant performance in N-limited *** that N translocation or cycling is crucial,and the potential benefits of N transfer are great in both agricultural and natural ecosystems,more research is warranted on either oneway or two-way N transfers mediated by CMNs with different species and under field conditions.

关键词： ^(15)N enrichment ^(15)N natural abundance(^(15)N) ^(15)N stable isotope common mycorrhizal networks(CMNs) nitrogen transfer

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Asymmetric electrode design with built-in nitrogen transfer channel achieving maximized three-phase reaction region for electrochemical ammonia synthesis

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Electron 2023年第1期1卷 50-58页

作者： Chao Wang Qiyang Cheng Mengfan Wang Sisi Liu Yanzheng He Chengwei Deng Yi Sun Tao Qian Na Xu Federico Rosei Chenglin Yan Collaborative Innovation Center of Suzhou Nano Science and Technology College of EnergySoochow UniversitySuzhouChina Aerospace Hydrogen Energy Technology(Shanghai)Co.Ltd. ShanghaiChina School of Chemistry and Chemical Engineering Nantong UniversityNantongChina Light Industry Institute of Electrochemical Power Sources SuzhouChina Institut National de la Recherche Scientifique VarennesQuebecCanada

Carbon-free electrochemical nitrogen reduction reaction(NRR)is an appealing strategy for green ammonia synthesis,but there is still a significant performance *** working electrode is usually flooded by the electrolyte during the NRR test,and only the surface material could get access to the nitrogen,which inevitably gives rise to sluggish reaction ***,an asymmetric electrode design is proposed to tackle this *** aerophilic layer is constructed on one face of the electrocatalyst-loaded electrode,while the other side maintains its original structure,aiming to achieve facilitated nitrogen transfer and electrolyte permeation within the conductive skeleton *** asymmetric architecture affords extensive threephase reaction region within the electrode as demonstrated by the combination of theoretical simulations and experimental measurements,which gives full play to the loaded *** expected,the proofof-concept asymmetric electrode delivers an NH_(3)yield rate of 40.81μg h^(−1)mg^(−1)and a Faradaic efficiency of 71.71%at−0.3 V versus the reversible hydrogen electrode,which are more than 4 and 7 times that of conventional electrode,*** work presents a versatile strategy for enhancing the interfacial reaction kinetics and is instructive to electrode design for gas-involved electrochemical reactions.

关键词： ammonia synthesis asymmetric electrode nitrogen reduction nitrogen transfer threephase reaction region

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Potential Impacts of Exogenous nitrogen Enrichment on Distribution and transfer of nitrogen in Plant-Soil System of Suaeda salsa Marsh in the Yellow River Estuary, China

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Journal of Ocean University of China 2023年第1期22卷 258-270页

作者： HU Xingyun SUN Zhigao YU Linying CHEN Bingbing Fujian Provincial Key Laboratory for Subtropical Resources and Environment Fujian Normal UniversityFuzhou 350007China Key Laboratory of Humid Subtropical Eco-Geographical Process(Fujian Normal University) Ministry of EducationFuzhou 350007China Institute of Geography Fujian Normal UniversityFuzhou 350007China

To determine the potential impacts of exogenous nitrogen(N)enrichment on distribution and transfer of N in Suaeda salsa marsh in the Yellow River Estuary,the variations of N in plant-soil system during the growing season were investigated by field N addition *** experiment included four treatments:NN(no N input treatment,0gNm^(−2) yr^(−1)),LN(low N input treatment,3.0 gNm^(−2) yr^(−1)),MN(medium N input treatment,6 gNm^(−2) yr^(−1))and HN(high N input treatment,12 gNm^(−2) yr^(−1)).Results showed that N additions generally increased the contents of total nitrogen(TN),ammonia nitrogen(NH_(4)^(+)-N)and nitrate nitrogen(NO_(3)^(−)-N)in different soil layers and the increasing trend was particularly evident in *** with the NN treatment,the average contents of TN in topsoil in the LN,MN and HN treatments during the growing season increased by 10.85%,30.14%and 43.98%,the mean contents of NH_(4)^(+)-N increased by 8.56%,6.96%and 14.34%,and the average contents of NO_(3)^(−)-N increased by 35.73%,45.99%and 46.66%,*** exogenous N import did not alter the temporal variation patterns of TN contents in organs,the N transfer and accumulation differed among tissues in different *** increasing N import,both the N stocks in soil and plant showed increasing trend and the values in N addition treatments increased by 9.43%–38.22%and 13.40%–62.20%,*** was worth noting that,compared with other treatments,the *** in the MN treatments was very likely to have special response to N enrichment since not only the period of peak growth was prolonged by about 20 days but also the maximum of TN content in leaves was advanced by approximately one *** paper found that,as N loading reached MN level in future,the growth rhythm of *** and the accumulation and transference of N in its tissues would be altered significantly,which might generate great impact on the stability and health of *** marsh ecosystem.

关键词： nitrogen import nitrogen transfer plant-soil system Suaeda salsa Yellow River Estuary

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transfer characteristics of nitrogen fixed by leguminous green manure crops when intercropped with maize in northwestern China

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Journal of Integrative Agriculture 2022年第4期21卷 1177-1187页

作者： LIU Rui ZHOU Guo-peng CHANG Dan-na GAO Song-juan HAN Mei ZHANG Jiu-dong SUN Xiao-feng CAO Wei-dong Institute of Soil and Fertilizer Qinghai Academy of Agriculture and Forestry Sciences/The Graduate SchoolQinghai UniversityXining 810016P.R.China Key Laboratory of Plant Nutrition and Fertilizer Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China College of Resources and Environmental Sciences Nanjing Agricultural UniversityNanjing 210095P.R.China Institute of Soil and Fertilizer and Water-saving Gansu Academy of Agricultural SciencesLanzhou 730070P.R.China

To ascertain the possibility of cultivating maize using biological nitrogen fixation(BNF)by leguminous green manure crops in maize/leguminous green manure intercropping systems,BNF and nitrogen(N)transfer were studied in Xining and Wuwei,two typical northwestern Chinese *** experimental treatments included monocultured maize,monocultured green manures(hairy vetch and common vetch),and their intercropping *** proportions of N derived from the atmosphere(%N_(dfa))in intercropping systems were not significantly different from that in monocultured green manure systems at either experimental site,except for that in hairy vetch(HV)in *** amount of N derived from the atmosphere(N_(dfa))of common vetch(CV)significantly decreased from 1.16 and 1.10 g/pot in monoculture to 0.77 and 0.55 g/pot when intercropped with maize,in Xining and Wuwei,respectively,and the N_(dfa) of HV when intercropped significantly decreased from 1.02 to 0.48 g/pot in *** the intercropping systems in Xining and Wuwei,the amounts of N transferred(N_(transfer))from CV to maize were 21.54 and 26.81 mg/pot,accounting for 32.9 and 5.9%respectively of the N accumulation in maize,and the values of N_(transfer) from HV to maize were 39.61 and 46.22 mg/pot,accounting for 37.0 and 23.3%,respectively,of the N accumulation in *** analysis showed that soil nutrient and green manure biomass were mainly related to N_(dfa),and thatδ^(15) N had a primary relationship with N_(transfer).We found that 5.9-37.0%of N accumulation in maize was transferred from green manures,and that the N transfer ability to maize of HV was higher than that of *** conclusion,intercropping with leguminous green manures provided a feasible way for maize to effectively utilize biologicallyfixed N.

关键词： green manure maize intercropping biological nitrogen fixation nitrogen transfer

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Photocatalytic divergent decarboxylative amination: a metal-free access to aliphatic amines and hydrazines

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Science China Chemistry 2021年第10期64卷 1756-1762页

作者： Xianli Shu Ruting Xu Saihu Liao Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) State Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou UniversityFuzhou 350108China Beijing National Laboratory for Molecular Sciences Beijing 100190China

nitrogen-containing motifs are widely present in natural products, bioactive molecules, and drugs. Accordingly, effective synthetic methods with high efficiency and diversity are highly desirable. Here, we present the invention of a facile, visible lightmediated decarboxylative C(sp^(3))–N bond-forming reaction by employing abundant carboxylic acids as the feedstock and a commercial diazirine as a nitrogen donor. This process is amenable to access both imines and diaziridines, as the corresponding masked amines and hydrazines, through a selectable single or double nitrogen transfer from the diazirine, respectively. This divergent approach works well in both directions with various alkyl carboxylic acids, including primary, secondary, and tertiary acids, as well as natural products and drugs, thus affording a rapid, metal-free approach to build nitrogen-containing molecule libraries with considerable structural diversity, which could thus benefit the related study in context of chemical biology and drug discovery.

关键词： decarboxylative amination divergent synthesis nitrogen transfer amines diazirines

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nitrogen rhizodeposition from corn and soybean,and its contribution to the subsequent wheat crops

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Journal of Integrative Agriculture 2024年第7期23卷 2446-2457页

作者： Sainan Geng Lantao Li Yuhong Miao Yinjie Zhang Xiaona Yu Duo Zhang Qirui Yang Xiao Zhang Yilun Wang College of Resources and Environment Henan Agricultural UniversityZhengzhou 450002China

nitrogen(N)is a key factor in the positive response of cereal crops that follow leguminous crops when compared to gramineous crops in rotations,with the nonrecyclable rhizosphere-derived N playing an important ***,quantitative assessments of differences in the N derived from rhizodeposition(NdfR)between legumes and gramineous crops are lacking,and comparative studies on their contributions to the subsequent cereals are *** this study,we conducted a meta-analysis of NdfR from leguminous and gramineous crops based on 34 observations published *** addition,pot experiments were conducted to study the differences in the NdfR amounts,distributions and subsequent effects of two major wheat(Triticum aestivum L.)-preceding crops,corn(Zea mays L.)and soybean(Glycine max L.),by the cotton wick-labelling method in the main wheat-producing areas of *** meta-analysis results showed that the NdfR of legumes was significantly greater by 138.93%compared to gramineous *** our pot experiment,the NdfR values from corn and soybean were 502.32 and 944.12 mg/pot,respectively,and soybean was also significantly higher than corn,accounting for 76.91 and 84.15%of the total belowground nitrogen of the plants,***,in different soil particle sizes,NdfR was mainly enriched in the large macro-aggregates(>2 mm),followed by the small macro-aggregates(2–0.25 mm).The amount and proportion of NdfR in the macro-aggregates(>0.25 mm)of soybean were 3.48 and 1.66 times higher than those of corn,respectively,indicating the high utilization potential of soybean *** the N accumulation of subsequent wheat,the contribution of soybean NdfR to wheat was approximately 3 times that of corn,accounting for 8.37 and 4.04%of the total N uptake of wheat,*** conclusion,soybean NdfR is superior to corn in terms of the quantity and distribution ratio of soil *** future field production,legume NdfR should be included in the nitrogen p

关键词： crop rotation nitrogen rhizodeposition meta-analysis soil aggregates nitrogen transfer

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Influence of welding parameters on nitrogen content in welding metal of 32Mn-7Cr-1Mo-0.3N austenitic steel

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Journal of Central South University of Technology 2005年第1期12卷 22-26页

作者：付瑞东邱亮王存宇王青峰郑炀曾 Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China School of Materials Science and Engineering Yanshan University Qinhuangdao 066004 China

The transfer behavior of nitrogen into the welding metal during gas tungsten arc welding process of 32Mn-7Cr-1Mo-0.3N steel was investigated. The effects of gas tungsten arc welding process variables, such as the volume fraction of nitrogen in shielding gas, arc holding time and arc current on the nitrogen content in the welding metal were also evaluated. The results show that the volume fraction of nitrogen in gas mixture plays a major role in controlling the nitrogen content in the welding metal. It seems that there exhibits a maximum nitrogen content (depending) on the arc current and arc holding time. The optimum volume fraction of nitrogen in shielding gas is 4% or so. The role of gas tungsten arc welding processing parameters in controlling the transfer of nitrogen is further (confirmed) by the experimental results of gas tungsten arc welding process with feeding metal.

关键词： nitrogen transfer welding parameter high manganese austenitic steel deposit gas tungsten arc welding

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Better tillage selection before ridge–furrow film mulch can facilitate root proliferation, and increase nitrogen accumulation,translocation and grain yield of maize in a semiarid area

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Journal of Integrative Agriculture 2023年第6期22卷 1658-1670页

作者： ZHANG Miao-miao DANG Peng-fei LIYu-ze QIN Xiao-liang Kadambot H.M.SIDDIQUE College of Agronomy/Key Laboratory of Crop Physio-ecology and Tillage Science in Northwestern Loess Plateau Northwest A&F UniversityYangling 712100P.R.China The UWA Institute of Agriculture and School of Agriculture&Environment The University of Western AustraliaPerth WA 6001Australia

Plastic film mulch systems are used widely in arid areas, and the associated tillage measures affect soil properties, root and crop growth, and nutrient uptake. However, much debate surrounds the most suitable tillage method for plastic film mulch systems. We conducted a two-year field experiment to explore the impact of three tillage treatments-rotary tillage before ridge–furrow plastic film mulch(MR), no-tillage before ridge–furrow plastic film mulch(MZ), and plow tillage before ridge–furrow plastic film mulch(MP)-on soil total nitrogen, available nitrogen, root stratification structure,nitrogen transfer and utilization, and maize yield. The results showed that MP had better soil quality than either MR or MZ over 2019 and 2020, with higher nitrate-nitrogen and total nitrogen in the 0–40 cm soil layer. MP improved the soil physicochemical properties more than the other treatments, producing significantly higher root numbers and root biomass for the aerial and underground nodal roots than MR and MZ. At harvest, MP had the highest root biomass density,root length density, and root surface area density in the different soil layers(0–20, 20–40, and 0–40 cm). Significant correlations occurred between root biomass and aboveground nitrogen accumulation during maize growth. During grain filling, MP had the greatest nitrogen transfer amount, significantly increasing root and aboveground nitrogen transfer by 19.63–45.82% and 11.15–24.56%, respectively, relative to the other treatments. MP significantly produced 1.36–26.73%higher grain yields and a higher grain crude protein content at harvest than MR and MZ. MP also had higher values for the nitrogen harvest index, nitrogen uptake efficiency, and partial factor productivity of nitrogen fertilizer than MR and *** conclusion, plow tillage combined with a ridge–furrow plastic film mulch system facilitated maize root development and improved nitrogen utilization, thereby increasing maize yield more than the other treatments.

关键词： maize tillage plastic film mulch root nitrogen transfer

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