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Soil organic carbon stocks in native forest of Argentina:a useful surrogate for mitigation and conservation planning under climate variability

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Ecological Processes 2024年第1期13卷 3-24页

作者： Pablo L.Peri Juan Gaitán matías Mastrangelo Marcelo Nosetto Pablo E.Villagra Ezequiel Balducci Martín Pinazo Roxana P.Eclesia Alejandra Von Wallis Sebastián Villarino Francisco Alaggia Marina González Polo Silvina Manrique Pablo A.Meglioli Julián Rodríguez-Souilla Martín Mónaco Jimena E.Chaves Ariel Medina Ignacio Gasparri Eugenio Alvarez Arnesi María Paula Barral Axel von Müller Norberto M.Pahr Josefina Uribe Echevarria Pedro Fernández Marina Morsucci Dardo López Juan Manuel Cellini Leandro Alvarez Ignacio Barberis Hernán Colomb Ludmila La Manna Sebastián Barbaro Cecilia Blundo Ximena Sirimarco Laura Cavallero Gualberto Zalazar Guillermo Martínez Pastur Instituto Nacional de Tecnología Agropecuaria (INTA) Universidad Nacional de la Patagonia Austral (UNPA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Luján Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Grupo de Estudio de Agroecosistemas y.Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET ) CCT San Luis Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto Argentino de Nivología Glaciología y Ciencias Ambientales (IANIGLA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Cuyo Instituto de Investigaciones en Biodiversidad y.Medioambiente (INIBIOMA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto de Investigaciones en Energía No Convencional CCT Salta-JujuyConsejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas (CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Dirección Nacional de Bosques Ministerio de Ambiente y Desarrollo Sostenible de la Nación Instituto de Ecología Regional Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )Universidad Nacional de Tucumán Universidad Nacional de Rosario Instituto de Investigaciones en Ciencias Agrarias de Rosario Centro Científico Tecnológico CONICET Grupo de Estudio de Agroecosistemas y.Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Investigaciones en Maderas (LIMAD) Universidad Nacional de La Plata (UNLP) Administración de Parques Nacionales (APN) Parque Nacional Los Alerces Centro de Estudios Ambientales Integrados (CEAI) Universidad Nacional de la Patagonia San Juan Bosco (UNPASJB) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )

Background The nationally.determined contribution（NDC） presented by.Argentina within the framework of the Paris Agreement is aligned with the decisions made in the context of the United Nations Framework Conven-tion on Climate Change（UNFCCC） on the reduction of emissions derived from deforestation and forest degradation, as well as forest carbon conservation（REDD+）. In addition, climate change constitutes one of the greatest threats to forest biodiversity.and ecosy.tem services. However, the soil organic carbon（SOC） stocks of native forests have not been incorporated into the Forest Reference Emission Levels calculations and for conservation planning under cli-mate variability.due to a lack of information. The objectives of this study.were:（i） to model SOC stocks to 30 cm of native forests at a national scale using climatic, topographic and vegetation as predictor variables, and（ii） to relate SOC stocks with spatial–temporal remotely.sensed indices to determine biodiversity.conservation concerns due to threats from high inter-annual climate *** We used 1040 forest soil samples（0–30 cm） to generate spatially.explicit estimates of SOC native forests in Argentina at a spatial resolution of approximately.200 m. We selected 52 potential predictive environmental covari-ates, which represent key.factors for the spatial distribution of SOC. All covariate maps were uploaded to the Google Earth Engine cloud-based computing platform for subsequent modelling. To determine the biodiversity.threats from high inter-annual climate variability. we employ.d the spatial–temporal satellite-derived indices based on Enhanced Vegetation Index（EVI） and land surface temperature（LST） images from Landsat *** SOC model（0–30 cm depth） prediction accounted for 69% of the variation of this soil property.across the whole native forest coverage in Argentina. Total mean SOC stock reached 2.81 Pg C（2.71–2.84 Pg C with a probability.of 90%） for a total area of 460,790 km2,

关键词： Soil organic carbon Biodiversity Native forest Climate change mitigation Modelling Resilience

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Optimization of the Phase Diagram of CeO_2-ZrO_2 Sy.tem

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Journal of materials Science & Technology 1996年第2期12卷 159-160页

作者： Lin LI (Dept. of materials Science and Engineering, Shanghai University. Shanghai 200072, China)Zuy.o XU (T.y.Hsu)(Dept. of materials Science, Shanghai Jiao Tong University. Shanghai 200030, China)Qing AO (Dept. of materials Engineering, Shandong Poly.ech SHANGHAI JIAO TONG UNIV DEPT MAT SCISHANGHAI 200030PEOPLES R CHINA SHANDONG POLy.ECH UNIV DEPT MAT ENGNJINAN 250014PEOPLES R CHINA

Revised phase diagram of the CeO2-ZrO2 sy.tem is optimized and the lattice stability.parameters of CeO2 of various phases as well as solution parameters of phases (liquid, cubic, tetragonal and monoclinic) are simulta... 详细信息

关键词： Optimization of the Phase Diagram of CeO2-ZrO2 Sy.tem Am

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STUDy.ON SEVERAL INFLUENCE FACTORS OF WELDED STRUCTURES IN FATIGUE TEST

STUDY ON SEVERAL INFLUENCE FACTORS OF WELDED STRUCTURES IN F...

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第一届国际机械工程学术会议

作者： Liu G N Zhang X H Zhao M H Liu y.J (NAMT Center Zhengzhou Research Institute of Mechanical Engineering)Zhang J S Liu T Tao y.Liu y.(CAD Center Zhengzhou Research Institute of Mechanical Engineering)

＜正＞ Three steel materials used widely.in Chinese industry.l] have been chosen to study.the fatigue characters of welded structures under various *** on the fatigue testing results that correspond to different stress ratios,loading methods,and dimensions of the welded joints,the relations among these influential factors are obtained mat may.help predict the fatigue lives under an actual *** addition,the stress analy.es are also made to find out the influence of the shape of a welding line on the fatigue life of a welded joint

关键词： Welded structures Fatigue Influence factors SCF S-N curves

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Investigation of Instability.of Lattice of Bi_2Sr_2CaCu_2O_x

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Journal of materials Science & Technology 1996年第3期12卷 175-179页

作者： Han ZHANG and Qingrong FENG (Dept. of Phy.ics, Peking University. Beijing 100871, China)y.Zhao(School of materials Science and Engineering, University.of New South Wales, Sy.ney.2052, NSW, Australia)F.Ritter and W.Assmus (Phy.ikalisches Institut, J.W.Goet UNIV NEW S WALES SCH MAT SCI & ENGNSYDNEYNSW 2052AUSTRALIA UNIV FRANKFURT INST PHYSD-60054 FRANKFURTGERMANY

Bi2Sr2CaCu2Ox superconductor was studied by.differential scanning calorimetry.(DSC) and thermogravimetry.(TG) in different atmospheres. It is discovered that there is a thermal anomaly.in the DSC curve, associated with a weight loss in the TG curve before the melting of the sample. Careful thermal analy.is and high temperature X-ray.diffraction reveal that the thermal anomaly.and the weight loss show an instability.of the cry.talline Iattice. By.annealing the sample in oxy.en and argon, respectively.and then by.TC measurement and thermal analy.is, the coincidence of transition temperature with the instability.is found. The coincidence is further confirmed by.y.doped 2212 phase.

关键词： Sr Bi

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CHEMICAL PRETREATMENTS OF THE SURFACE OF WC-15wt%Co WITH DIAMOND COATINGS

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 143-147页

作者： S. Liu, Z.M. y., D.Q. y. and y.X. Li (Department of materials Science & Engineering, Central South University. Changsha 410083, China) (Hunan y.n Zhou Nonferrous Metals Hi-Tech. Ltd. Company. Changsha 410083, China) Dept. of mat. Sci. and Eng. Central South Univ. Changsha 410083 China

Diamond films were deposited on the cemented carbide WC-15%Co substrates by.a hot-filament chemical vapor deposition (HF CVD) reactor. The substrate surfaces were chemically.pretreated by.the following two-step etching method: first using Murakami reagent for 1-3 min, and second using an HNO3:HCl=1:1 solution for 10-40 min. It is indicated that the Co content of the substrate surfaces could be reduced from 15% to 0.81-6.04% within the etching depth of 5-10μm, the surface roughness of the substrates was increased up to Ra=1.0μm, and the substrates hardness was decreased from 89.0 HRA to 83.0 HRA after the two-step etching. It is observed that the morphologies of the diamond films on the WC-15%wt Co substrates emerge in various shapes. The indentation testing shows that the good adhesion between diamond film and the substrate after HF CVD deposition could be obtained.

关键词： Chemical vapor deposition Cobalt Diamond films Surface treatment Tungsten carbide

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Environmental impacts on the distribution of microbial tetraether lipids in Chinese lakes with contrasting pH: Implications for lacustrine paleoenvironmental reconstructions

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Science China Earth Sciences 2016年第2期59卷 939-950页

作者： DANG Xiny.e XUE JianTao y.NG Huan XIE ShuCheng School of Earth Sciences China University of Geosciences State Key.Laboratory.of Biogeology.and Environmental Geology China University of Geosciences

Gly.erol dialky. gly.erol tetraethers(GDGTs) in lake sediments are useful biomarkers for the continental paleoclimatic reconstruction. However, the environmental controls on the distribution of these compounds, in particular the 6-methy. isomers of bacterial branched GDGTs(bGDGTs), in the lakes with contrasting pH, are still unknown, hindering their application for paleo-reconstructions. Here, we investigated the environmental impacts on the distribution of GDGTs in 17 alkaline lakes and 1 acid lake in China. It was found that the dissolved oxy.en content in water column may.have an impact on the distribution of archaeal isoprenoid GDGTs(iGDGTs) by.causing the change in archaeal communities. The ratio of GDGT-0/crenarchaeol increases with decreasing oxy.en content, indicating that the relative abundance of anaerobic methanogenic archaea or Miscellaneous Crenarchaeotic Group(MCG) vs. aerobic Thaumarchaeota is controlled by.the oxy.en content dissolved in water of these lakes. Thaumarchaeota are likely.to contribute only.a small proportion of iGDGTs in the relatively.oxy.en-depleted lakes, and thus TEX_(86) is not suitable for the reconstruction of the surface temperature of these lakes. The abundance ratio of iGDGTs to bGDGTs(R_(i/b)) appears to show no relationship with water pH in all the lakes, but exhibits a significant positive correlation with the water depth of the acid Lake Qinghai in Tengchong. As expected, the methy.ation degree of bGDGTs(MBT′) was found to correlate with both mean annual air temperature(mat) and water pH, and the cy.lization degree of bGDGTs(CBT) correlates only.with water pH in these lakes. However, the MBT′_(5ME), an index to measure the methy.ation degree of 5-methy. bGDGTs, exhibits no relationship with mat, whereas MBT′_(6ME), the methy.ation degree of 6-methy. bGDGTs, was found to correlate significantly.with mat. This is opposite to the situation observed in the global soils, pointing to a different adaptation of b GDGT-producing ba

关键词： GDGTs Lake 6-methy. bGDGTs pH IR

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Late Pleistocene/Early.Holocene climate conditions of North Mongolia based on carbon and oxy.en stable isotopes of Dood Lake sediments

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地球环境学报 2011年第1期 318-320页

作者： Narantsetseg Ts Tomurhuu D Oy.nchimeg Ts Tuvshingargal B Idermunkh T Krivonogov S Kuzmin y.Burr G Institute of Geology.and mineral resources Mongolian Academy of Sciences Korean Institute of Geosciences and Mineral Resources Institute of geology.and mineralogy.SB RAS Phy.ics Department University of Arizona

Lake Dood is a fresh water lake,remnant of a large glacial lake in the Darkhad *** Mongolia is located at the coordinate of 51°20’ N,99°23’E,in 1538 m a.s.l..The length of the lake is 7.5 km with mean width2.4 km（maximum width is 5.6 km）.Mean depth of the lake Dood is 4.7 m,but deepest point is 17 *** total area is about 41.3 km;.The climate of the Darkhad Basin is extremely.continental with a mean annual temperature range of 40 ℃ and a mean annual precipitation of 300;00 ***,the lake Dood occupies a transition zone between mountain and forest steppe ecosy.tems to the south and the coniferous forests to the *** of its unique geographic location,this region is very.sensitive to climate changes and ideal place for paleoclimate *** paper makes an attempt to reconstruct the paleoclimate changes in Early.Holocene and Late Pleistocene based on results of isotope geochemistry.analy.is of the core 1,obtained from the Lake Dood in North Mongolia,during the Mongolian-Russian joint expedition in summer of *** core 1 with length of 645 cm was taken from northern part of the lake,at coordinates of 51°24’26.0 "N;99°19’ 30.7" *** depth is 3.5 *** cores were cut lengthwise and after lithological description,it had been subsampled in 2 cm *** water,organic matter and carbonate contents of sediments were determined by.heating the selected 210 samples（approximately.5;0 cm intervals） at 105℃,550℃ and 1000℃,*** isotope ratios of carbon and oxy.en on bulk carbonate in 160 sediment samples were determined on Finnigan mat 252 mass spectrometer at Key.laboratory.of Lanzhou Institute of Geology.Chinese Academy.of *** ratios are reported relative to the Pee Dee Belemnite（PDB） standard for carbon and oxy.en isotope measurements on bulk CO,.Plant fragments,wood debris and shells from 11 samples from different horizons of core 1 were dated by.using Accelerator Mass Spectrometry.at the University.of Arizon

关键词： Lake Late Pleistocene/Early.Holocene climate conditions of North Mongolia based on carbon and oxy.en stable isotopes of Dood Lake sediments

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The Giant Radio Array.for Neutrino Detection(GRAND):Science and design

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Science China(Phy.ics,Mechanics & Astronomy. 2020年第1期63卷 1-43页

作者： Jaime Alvarez-Muniz Rafael Alves Batista Aswathi Balagopal V. Julien Bolmont Mauricio Bustamante Washington Carvalho Jr. Didier Charrier Ismael Cognard Valentin Decoene Peter B.Denton Sijbrand De Jong Krijn D.De Vries Ralph Engel Ke Fang Chad Finley.Stefano Gabici Quan Bu Gou Jun Hua Gu Claire Guépin Hong Bo Hu y.n Huang Kumiko Kotera Sandra Le Coz Jean-Philippe Lenain Guo Liang Léü Olivier Martineau-Huy.h Miguel Mostafá Fabrice Mottez Kohta Murase Valentin Niess Foteini Oikonomou Tanguy.Pierog Xiang Li Qian Bo Qin Duan Ran Nicolas Renault-Tinacci Markus Roth Frank G.Schroder Fabian Schüssler Cy.il Tasse Charles Timmerman matías Tueros Xiang Ping Wu Philippe Zarka Andreas Zech B.Theodore Zhang Jian Li Zhang y. Zhang Qian Zheng Anne Zilles Departamento de Fisica de Particulas&lnstituto Galego de Fisica de Altas Enerxias Universidad de Santiago de CompostelaSantiago de Compostela 15782Spain Instituto de Astronomia Geofisica e Ciencias AtmosfericasUniversidade de Sao PauloSao Paulo-SP 05508-090Brazil Department of Phy.ics-Astrophy.ics University of OxfordDWBOxford 0X13RHUK Institute of Experimental Particle Phy.ics(ETP) Karlsruhe Institute of Technology(KIT)Karlsru he D-76021Germany Laboratoire de Phy.ique Nucleeaire et de Hautes Energies(LPNHE) Sorbonne UniversiteUniversite Paris DiderotSorbonne Paris CiteCNRS place Jussieu F-75252Paris Cedex 5France Niels Bohr International Academy.and DARK Niels Bohr InstituteCopenhagen 2100Denmark Discovery.Center Niels Bohr InstituteCopenhagen 2100Denmark Center for Cosmology.and AstroParticle Phy.ics(CCA.PP)&Department of Phy.ics Ohio State UniversityColumbus OH 43210USA Universidade de Santiago de Compostela Santiago de Compostela 15782Spain 0SUBATECH Institut Mines-Telecom Atlantique-CNRS/IN2P3-Universite de NantesNantes 44300France Laboratoire de Phy.ique et Chimie de KEnvironnement et de VEspace LPC2E CNRS-Universite d'Orleans Orleans F-45071France Station de Radioastronomie de Nancay Observatoire de ParisCNRS/INSU F-18330 NangayFrance Sorbonne Universite UMR 7095Institut d'Astrophysique de Paris98 bis bd AragoParis 75014France Institute for mathematics Astrophysics and Particle Physics(IMAPP)Radboud UniversiteitNijmegen 6500Netherlands Nationaal Instituut voor Kemfy.ica en Hoge Energie Fy.ica(NIKHEF) Amsterdam NL-1009Netherlands IIHE/ELEM Vrije Universiteit BrusselPleinlaan 2Brussels 1050Belgium Institute for Nuclear Phy.ics(IKP) Karlsruhe Institute of Technology(KIT)Karlsruhe D-76021Germany Einstein Fellow Stanford UniversityStanford CA 94305USA Department of Astronomy University of MarylandCollege Park MD 20742-2421USA Joint Space-Science Institute College Park MD 20742-2421USA Oskar Klein Centre Stockholm UniversityStockholm SE-10691Sweden Department of Phy

The Giant Radio Array.for Neutrino Detection(GRAND)is a planned large-scale observatory.of ultra-high-energy.UHE)cosmic particles,with energies exceeding 10~8 Ge *** goal is to solve the long-standing my.tery.of the origin of UHE cosmic *** do this,GRAND will detect an unprecedented number of UHE cosmic ray. and search for the undiscovered UHE neutrinos and gamma ray. associated to them with unmatched *** will use large array. of antennas to detect the radio emission coming from extensive air showers initiated by.UHE particles in the *** design is modular:20 separate,independent sub-array.,each of 10000 radio antennas deploy.d over 10000 km^2.A staged construction plan will validate key.detection techniques while achieving important science goals *** we present the science goals,detection strategy.preliminary.design,performance goals,and construction plans for GRAND.

关键词： radio telescopes neutrinos in astronomical observations cosmic ray. in astronomical observations radiowave radiation:sources galactic and extragalactic cosmic ray.:galactic and extragalactic

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Characteristics of Joint Welded by.Laser Welding of Aluminium-Lithium Alloy.with Filler Wire

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稀有金属材料与工程 2011年第S4期40卷 138-141页

作者： y.ng J1,2,Li X y.,Gong S L2,Chen L2,Xu F2 1 School of material Science and Engineering,Beijing University.of Technology.Beijing 100083,China 2 Science and Technology.on Power Beam Processes Laboratory.Beijing Aeronautical Manufacturing Technology.Research Institute,Beijing 100024,China Beijing Aeronaut Mfg Technol Res Inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China Beijing Univ Technol Sch Mat Sci & Engn Beijing 100083 Peoples R China

The characteristics of weld shape,microstructure,mechanical properties and defects of 5A90 Al-Li alloy.joint by.laser welding (LBW) and laser welding with filler wire (LWFW) were studied and *** results indicated that the microstructure of joint by.LWFW was fine-grained lay.r and the equiaxed grain in most of seams,which were similar to the joint by.*** with the joint by.LBW,the microstructure of joint by.LWFW tended to fine,and the range of the columnar cry.tals zone was prone to *** Microhardness of the joint by.LWFW (92.57HV0.2) was lower than that by.LBW (95.65HV0.2),but the uniformity.was *** ultimate tensile strength of the joint by.LWFW was lower than that by.LBW slightly.which reached to 73.03% and 79.22% of the base metal ***,the elongation of the LWFW joint was higher than that of the LBW joint significantly.which reached to 38.65% and 20.38% of the base metal *** microstructure and mechanical properties of 5A90 Al-Li alloy.by.LWFW were better than that by.*** defects of joint were mainly.forming defects which were caused by.improper parameters and porosity.inside the joint,which was caused by.uncleaned surface and incomplete penetration.

关键词： Al-Li alloy laser beam welding (LBW) laser welding with filler wire (LWFW) weld shape microstructure mechani-cal properties defects

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大学数学分类分层次教学的研究与实践

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煤炭技术 2006年第4期25卷 122-124页

作者：关鲁玉黑龙江科技学院哈尔滨150027

近几年由于高校扩大招生,使得学生的数学基础很不一致。怎样提高大学数学的教学,使得不同基础的学生都能学好数学,黑龙江科技学院采取了分类分层次教学的研究与实践,对不同层次的学生实施不同的教学手段,这种做法得到了学生的认可,教学... 详细信息

近几年由于高校扩大招生,使得学生的数学基础很不一致。怎样提高大学数学的教学,使得不同基础的学生都能学好数学,黑龙江科技学院采取了分类分层次教学的研究与实践,对不同层次的学生实施不同的教学手段,这种做法得到了学生的认可,教学效果显著提高。

关键词：分类教学分层次教学教学方法

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