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Integrated management of crop residue and nutrient enhances new carbon formation by regulating microbial taxa and enzymes

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Journal of Integrative Agriculture 2022年第6期21卷 1772-1785页

作者： WU Hong-liang Cai An-dong XING Ting-ting HUai Sheng-chang ZHU Ping HAN Xiao-zeng XU Ming-gang lu chang-ai Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable LandBeijing 100081P.R.China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Institute of Agricultural Resources and Environment Jilin Academy of Agricultural SciencesChangchun 130033P.R.China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102P.R.China College of Resources and Environment Shanxi Agricultural UniversityTaiyuan 030031P.R.China

Although returning crop residue to fields is a recommended measure for improving soil carbon(C)stocks in agroecosystems,the response of newly formed soil C(NFC)to the integrated supply of residue and nutrients and the microbial mechanisms involved in NFC are not fully ***,an 84-day incubation experiment was conducted to ascertain the microbial mechanisms that underpin the NFC response to inputs of residue and nitrogen(N),phosphorus(P),and sulfur(S)in two black(Phaeozem)soils from experimental plots at Gongzhuling,Jilin Province and Hailun,Heilongjiang Province,*** results showed that adding residue alone accelerated microbial nutrient mining,which was supported by decreases of 8^(-1)6%in the ratios of C:N and C:P enzyme activities,relative to soils with nutrient *** NFC amounts increased from 1156 to 1722 mg kg^(−1) in Gongzhuling soil and from 725 to 1067 mg kg^(−1) in Hailun soil as the levels of nutrient supplementation *** regression tree analysis suggested thatβ-glucosidase(BG),acid phosphatase(AP),microbial biomass C(MBC),and Acidobacteria accounted for 27.8,18.5,14.7,and 8.1%,respectively,of the NFC in Gongzhuling soil and for 25.9,29.5,10.1,and 13.9%,respectively,of the NFC in Hailun *** analysis determined that Acidobacteria positively influenced NFC both directly and indirectly by regulating BG,AP,and MBC,in which MBC acquisition was regulated more by *** amount of NFC was lower in Hailun soil than in Gongzhuling soil and was directly affected by AP,indicating the importance of soil properties such as SOC and pH in determining ***,our results reveal the response of NFC to supplementation by N,P,and S,which depends on Acidobacteria and Proteobacteria,and their investment in BG and AP in residue-amended soil.

关键词： newly formed soil carbon extracellular enzyme activities gene abundance nutrient supplementation black soil

Increasing soil microbial biomass nitrogen in crop rotation systems by improving nitrogen resources under nitrogen application

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Journal of Integrative Agriculture 2022年第5期21卷 1488-1500页

作者： XING Ting-ting Cai An-dong lu chang-ai YE Hong-ling WU Hong-liang HUai Sheng-chang WANG Jin-yu XU Ming-gang LIN Qi-mei Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable LandBeijing 100081P.R.China College of Land Science and Technology China Agricultural UniversityBeijing 100094P.R.China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081P.R.China

Soil microbial biomass nitrogen(MBN)contains the largest proportion of biologically active nitrogen(N)in soil,and is considered as a crucial participant in soil N *** management practices such as crop rotation and monocropping systems,dramatically affect MBN in ***,the influence of crop rotation and monocropping in agroecosystems on MBN remains unclear.A meta-analysis based on 203 published studies was conducted to quantify the effect of crop rotation and mono-cropping systems on MBN under synthetic N fertilizer *** analysis showed that crop rotation significantly stimulated the response ratio(RR)of MBN to N fertilization and this parameter reached the highest levels in upland-fallow *** mono-cropping did not change the RR of MBN to N application,however,the RR of MBN to N application in paddy mono-cropping *** difference between crop rotation and mono-cropping systems appeared to be due to the various cropping management scenarios,and the pattern,rate and duration of N *** rotation systems led to a more positive effect on soil total N(TN)and a smaller reduction in soil pH than mono-cropping *** RR of MBN to N application was positively correlated with the RR of mineral N only in crop rotation systems and with the RR of soil pH only in mono-cropping *** the results of Random Forest(RF)model and structural equation model showed that the predominant driving factors of MBN changes in crop rotation systems were soil mineral N and TN,while in mono-cropping systems the main driving factor was soil ***,our study indicates that crop rotation can be an effective way to enhance MBN by improving soil N resources,which promote the resistance of MBN to low pH induced by intensive synthetic N fertilizer application.

关键词： microbial biomass nitrogen crop rotation systems mono-cropping systems synthetic nitrogen fertilizer meta-analysis

Assessment of the contribution percentage of inherent soil productivity of cultivated land in China

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Journal of Integrative Agriculture 2019年第11期18卷 2619-2627页

作者： WANG Shi-chao WANG Jin-zhou ZHAO Ya-wen REN Yi XU Ming-gang ZHANG Shu-xiang lu chang-ai National Engineering Laboratory of Farmland Cultivation Technology/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China The National Agro-Tech Extension and Service Center Beijing 100125P.R.China

The contribution percentage of inherent soil productivity(CPISP)refers to the ratio of crop yields under no-fertilization versus under conventional fertilization with the same field *** is a comprehensive measure of soil *** study used 1086 on-farm trials(from 1984-2013)and 27 long-term field experiments(from 1979-2013)to quantify changes in ***,we present CPISP3 values,which reflect the CPISP states during the first three years after site establishment,for a series of sites at different locations in China collected in 1984-1990(the 1980s),1996-2000(the 1990s),and 2004-2013(the 2000s).The results showed that the average CPISP3 value for three crops(wheat,rice,and maize)was 53.8%.Historically,the CPISP3 in the 1990s(57.5%)was much higher than those in the 1980s(50.3%),and the 2000s(52.0%)(P≤0.05).Long-term no-fertilization caused CPISP levels to gradually decline and then stabilize;for example,in a mono-cropping system with irrigation,the CPISP values in Northwest and Northeast China declined by 4.5 and 4.0%,respectively,each year for the first ten years,but subsequently,the CPISP values *** contrast,the CPISP for upland crops in double-cropping systems continued to decrease at a rate of 1.1%per *** CPISP for upland-paddy cropping decreased very slowly(0.07%per year),whereas the CPISP for paddy cropping decreased sharply(3.1%per year,on average)for the first two years and then remained steady during the following ***,upland crops in double-cropping systems consume the most inherent soil productivity,whereas paddy fields are favourable for maintaining a high level of ***,our results demonstrate a need to further improve China’s CPISP3 values to meet growing productivity demands.

关键词： crop yield inherent soil productivity typical cropping system planting years cropspecies

The efficiency of long-term straw return to sequester organic carbon in Northeast China＇s cropland

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Journal of Integrative Agriculture 2018年第2期17卷 436-448页

作者： WANG Shi-chao ZHAO Ya-wen WANG Jin-zhou ZHU Ping CUI Xian HAN Xiao-zeng XU Ming-gang lu chang-ai Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable Land Beijing 100081 P.R.China Jilin Academy of Agricultural Sciences Changchun 130124 P.R.China Heilongjiang Academy of Agricultural Sciences Heihe 164300 P.R.China Northeast Institute of Geography and Agro-ecology Chinese Academy of Sciences Harbin 150081 P.R. China

Black soil is one of the most precious soil resources on earth because it has abundant carbon stocks and a relatively high production capacity. However, decreasing organic matter after land reclamation, and the effects of long-term inputs of organic carbon have made it less fertile black soil in Northeast China. Straw return could be an effective method for improving soil organic carbon（SOC） sequestration in black soils. The objective of this study was to evaluate whether straw return effectively increases SOC sequestration. Long-term field experiments were conducted at three sites in Northeast China with varying latitudes and SOC densities. Study plots were subjected to three treatments： no fertilization（CK）; inorganic fertilization（NPK）; and NPK plus straw return（NPKS）. The results showed that the SOC stocks resulting from NPKS treatment were 4.0 and 5.7% higher than those from NPK treatment at two sites, but straw return did not significantly affect the SOC stocks at the third site. Furthermore, at higher SOC densities, the NPKS treatment resulted in significantly higher soil carbon sequestration rates（CSR） than the NPK treatment. The equilibrium value of the CSR for the NPKS treatment equated to cultivation times of 17, 11, and 8 years at the different sites. Straw return did not significantly increase the SOC stocks in regions with low SOC densities, but did enhance the C pool in regions with high SOC densities. These results show that there is strong regional variation in the effects of straw return on the SOC stocks in black soil in Northeast China. Additional cultivations and fertilization practices should be used when straw return is considered as an approach for the long-term improvement of the soil organic carbon pool.

关键词： soil organic carbon(SOC) SOC stock straw return soil sequestration rate straw-C sequestration efficiency black soil long-term experiments

Satellite and Ground Support Equipment for Space Solar Telescope

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Aerospace China 2003年第3期4卷 13-17页

作者： lu chang, Geng Lihong, ai Guoxiang, Jin Shengzhen

Space Solar Telescope (SST) is an astronomical satellite that will be traveling in the sun-synchro-nous polar circular orbit. It is expected to access creative new observation results of the solar magnetic field

关键词：太空太阳望远镜人造卫星地面设备运行轨道有效载荷发射地点

Preparation of Polyurea Elastomer with Flame Retardant, Insulation and Thermal Conductivity Properties

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 781-789页

作者：方今 DONG Yang lu Shangkai LIU Junbang ai Lianghui 刘平 State Key Laboratory of luminescent Materials and Devices Research Institute of Materials ScienceSouth China University of TechnologyGuangzhou 510640China

By using 6,6-((sulfonylbis(4,1-phenylene)bis(azanediyl))bis(thiophen-2-ylm-ethylene))bis6H-di-benzo[c,e][1,2]oxaphosphinine 6-oxide(DOPO-N)as phosphorus-nitrogen flame retardant,the polyurea(PUA)with flame retardant properties(PUA/DOPO-N)was *** addition,organically modified montmorillonite(OMMT)and magnesium hydroxide(MH)were used as co-effectors respectively,and the flame retardant PUA(PUA/DOPO-N/OMMT and PUA/DOPO-N/MH)were also *** properties,flame retardant properties,flame retardant mechanism and mechanical properties of PUA/DOPO-N,PUA/DOPO-N/OMMT and PUA/DOPO-N/MH were investigated by thermogravimetric(TG)analysis,limiting oxygen index(LOI),UL 94,cone calorimeter test,scanning electron microscopy(SEM),and tensile *** results show that the LOI value of PUA/20%DOPO-N,PUA/18%DOPO-N/2%OMMT and PUA/15%DOPO-N/5%MH are 27.1%,27.7%,and 28.3%,respectively,and UL 94 V-0 rating is *** with PUA,the peak heat release rate(pk-HRR),total heat release(THR)and average effective heat combustion(av-EHC)of PUA/20%DOPO-N,PUA/18%DOPO-N/2%OMMT and PUA/15%DOPO-N/5%MH decrease *** results indicate that the residual chars of PUA/20%DOPO-N,PUA/18%DOPO-N/2%OMMT and PUA/15%DOPO-N/5%MH are completer and more *** complex of DOPO-N/OMMT and DOPO-N/MH have synergistic flame *** mechanical properties of PUA can be improved by the addition of DOPO-N,DOPO-N/OMMT and DOPO-N/MH,*** insulation performance test shows that the volume resistivity of PUA/20%DOPO-N is 6.25×10^(16)Ω.***,by using modified boron nitride(MBN)as heat dissipating material,the complex of PUA/MBN was prepared,and the thermal conductivity of PUA/MBN was *** thermal conductivity of PUA/8%MBN complex coating at room temperature is 0.166 W/(M·K),which is a 163%improvement over pure PUA.

关键词： polyurea organic flame retardant inorganic flame retardant synergistic flame retardancy insulation thermal conductivity

The unique spontaneous polarization property and application of ferroelectric materials in photocatalysis

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Nano Research 2024年第5期17卷 3571-3585页

作者： Jinghua An chang Xu lu Li Bo Tang College of Chemistry Chemical Engineering and Materials ScienceKey Laboratory of Molecular and Nano ProbesMinistry of EducationCollaborative Innovation Center of Functionalized Probes for Chemical Imaging in University of ShandongInstitute of Molecular and Nano ScienceShandong Normal UniversityJinan 250014China Laoshan Laboratory 168 Wenhai Middle RdAoshanwei JimoQingdao 266237China

The unique spontaneous polarization property of ferroelectric material makes it to be a special catalyst in *** spontaneous polarization property can induce the formation of built-in electric field,which can improve the separation of photoelectrons and holes to affect photocatalytic *** internal electric field induced by spontaneous polarization can be influenced by multiple factors such as the morphology,the concentration of defect,the type of doped heteroatoms,as well as the composition of ***,the preparation method,pretreating temperature,the strength of prepolarized external electric field of ferroelectric-based photocatalysts as well as the strength of external mechanical force or external magnetic field in photocatalytic reactions can influence the photocatalytic effectivity via influencing spontaneous polarization-induced internal electric ***,it is urgently to unveil the mystery of structure-activity relationships for ferroelectric materials-based photocatalysts,which is usually *** this in mind,this review was provided for the role of various complex influencing factors on ferroelectric materials-based photocatalysis based on the latest advancement in the fields of new energy development,environmental *** the beginning,the basic structure and properties of ferroelectric material are ***,popular synthesis methods of ferroelectric-based photocatalysts are *** that,two main mechanisms of ferroelectric photocatalysis are *** research progress of ferroelectric photocatalysis is then given emphatically according to the classification of photocatalytic ***,the problems existing nowadays and the challenges facing in the future on the application of ferroelectric materials-based photocatalysts are outlined in the summary and outlook section.

关键词： spontaneous polarization photocatalysis ferroelectric separation of electrons and holes

Ion and electron motions in the outer electron diffusion region of collisionless magnetic reconnection

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Earth and Planetary Physics 2024年第3期8卷 472-478页

作者： Cong chang QuanMing lu San lu Kai Huang RongSheng Wang Deep Space Exploration Laboratory School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences(CAS)Center for Excellence in Comparative Planetology CAS Key Laboratory of Geospace EnvironmentHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China

Two-dimensional particle-in-cell simulations are performed to study the coupling between ion and electron motions in collisionless magnetic *** electron diffusion region(EDR),where the electron motions are demagnetized,is found to have a two-layer structure:an inner EDR near the reconnection site and an outer EDR that is elongated to nearly 10 ion inertial lengths in the outflow *** the inner EDR,the speed of the electron outflow increases when the electrons move away from the X *** the outer EDR,the speed of the electron outflow first increases and then decreases until the electrons reach the boundary of the outer *** the boundary of the outer EDR,the magnetic field piles up and forms a depolarization *** the perspective of the fluid,a force analysis on the formation of electron and ion outflows has also been *** the X line,the electrons are accelerated by the reconnection electric field in the out-of-plane *** the electrons move away from the X line,we find that the Lorentz force converts the direction of the accelerated electrons to the x direction,forming an electron *** electric field forces and electron gradient forces tend to drag the electron *** acceleration along the x direction is caused by the Lorentz force,whereas the pressure gradient force tends to decelerate the ion *** these two terms are important,their effects on ions are almost *** Hall electric field force does positive work on ions and is not *** ions are continuously accelerated,and the ion and electron outflow velocities are almost the same near the depolarization front.

关键词： collisionless magnetic reconnection electron diffusion region force analysis particle-in-cell simulation

A toroidal SAW gyroscope with focused IDTs for sensitivity enhancement

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Microsystems & Nanoengineering 2024年第2期10卷 47-56页

作者： lu Tian Haitao Zhao Qiang Shen Honglong chang Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an710072China

A surface acoustic wave(SAW)gyroscope measures the rate of rotational angular velocity by exploiting a phenomenon known as the SAW gyroscope *** a gyroscope is a great candidate for application in harsh environments because of the simplification of the suspension vibration mechanism necessary for traditional microelectromechanical system(MEMS)***,for the first time,we propose a novel toroidal standing-wave-mode SAW gyroscope using focused interdigitated transducers(FIDTs).Unlike traditional SAW gyroscopes that use linear IDTs to generate surface acoustic waves,which cause beam deflection and result in energy dissipation,this study uses FIDTs to concentrate the SAW energy based on structural features,resulting in better focusing performance and increased SAW *** experimental results reveal that the sensitivity of the structure is 1.51µV/(°/s),and the bias instability is 0.77°/s,which are improved by an order of magnitude compared to those of a traditional SAW ***,the FIDT component can enhance the performance of the SAW gyroscope,demonstrating its superiority for angular velocity *** work provides new insights into improving the sensitivity and performance of SAW gyroscopes.

关键词： angular deflection gyroscope