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Effects of plant species richness on stand structure and productivity

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Journal of Plant Ecology 2009年第2期2卷 95-106页

作者： Luca Wacker Oksana Baudois Susann Eichenberger-Glinz Bernhard schmid Institute of Environmental Sciences University of ZurichWinterthurerstrasse 190CH-8057 ZurichSwitzerland

Aims Aboveground biomass production commonly increases with species richness in plant biodiversity *** is known about the direct mechanisms that cause this *** tested if by occupying different heights and depths above and below ground,and by optimizing the vertical distribution of leaf nitrogen,species in mixtures can contribute to increased resource uptake and,thus,increased productivity of the community in comparison with *** We grew 24 grassland plant species,grouped into four nonoverlapping species pools,in monoculture and 3-and 6-species mixture in spatially heterogeneous and uniform soil nutrient *** harvests of above-and belowground biomass,as well as leaf nitrogen and light measurements,were taken to assess vertical canopy and root space *** Findings The distribution of leaf mass was shifted toward greater heights and light absorption was correspondingly enhanced in *** ever,only some mixtures had leaf nitrogen concentration profiles predicted to optimize whole-community carbon gain,whereas in other mixtures species seemed to behave more‘selfish’.Nevertheless,even in these communities,biomass production increased with species *** distribution of root biomass below ground did not change from monocultures to three-and six-species mixtures and there was also no indication that mixtures were better than monocultures at extracting heterogeneously as compared to homogeneously distributed soil *** conclude that positive biodiversity effect on aboveground biomass production cannot easily be explained by a single or few common mechanisms of differential space ***,it seems that mechanisms vary with the particular set of species combined in a community.

关键词： biodiversity effects heterogeneous nutrient distribution leaf nitrogen allocation root biomass distribution spatial niche separation

Phases equilibrated with long-period stacking ordered phases in the Mg-rich corner of the Mg-Y-Zn system

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Journal of Materials Science & Technology 2021年第9期68卷 147-159页

作者： Yongxin Ruan Changrong Li Yuping Ren Xiaopan Wu schmid-Fetzer Cuiping Guo Zhenmin Du School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Institute of Metallurgy Clausthal University of TechnologyRobert-Koch-Str.42D-38678 Clausthal-ZellerfeldGermany

Phase equilibria involving the long-period stacking ordered phases including 14 H,18 R and 10 H in the Mg-rich corner of the Mg-Y-Zn system at 400 and 500℃ have been experimentally investigated by using X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM).The coexistence of 14 H and 18 R as well as 18 R and 10 H was confirmed from atomic *** phases 14 H,18 R and 10 H were all stable phases from 400 to 500℃.The experimentally proved three-phase equilibrium of14 H,18 R and α-Mg instead of 14 H,18 R and Mg_(24)Y_(5) were presented in the modified isothermal *** latter three-phase equilibrium was reported in the available *** modified isothe rmal sections are conducive to guide the composition design to obtain the alloys with favorable microstructure constituents and mechanical properties.

关键词： Mg-Y-Zn system LPSO phases solubility thermodynamic stability isothermal sections

Sulphite measurement and its influence on Hg behaviour in wet-limestone flue-gas desulphurization

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Clean Energy 2020年第4期4卷 360-371页

作者： Ida Masoomi Sophia Bruttel Marc Oliver schmid Günter Scheffknecht Univ.-Prof.Dr.techn.Günter Scheffknecht University of StuttgartInstitute of Combustion and Power Plant Technology—IFKPfaffenwaldring 23D-70569 StuttgartGermany

The most abundant and typical reducing agent for oxidized mercury in the slurry of wet flue-gas desulphurization(FGD)is the absorbed sulphur dioxide(SO_(2)),which is present as different species of bisulphite or sulphite,depending on the pH of the *** this study,two different measurement principles for continuous sulphite measurement in the slurry of lab-scale FGD were investigated to check their feasibility to be implemented in a wet *** first method is based on light absorbance at the characteristic wavelength of sulphite measurement using a spectrophotometer and,in the second method,sulphite is measured as sulphur dioxide using a gas *** addition,the correlation of sulphite concentration and mercury(Hg)in the slurry can be shown by measuring sulphite *** was concluded that using a spectrophotometer leads to distorted *** contrast,measuring sulphite as SO2 in the gas phase proved to be more *** implementation of the measurement technique in the lab-scale FGD showed promising results for sulphite ***,the correlation of Hg and sulphite concentration could be shown at different synthetic slurries containing different *** a slurry without halides demonstrated the ambivalent influence of sulphite in reactions involving Hg,in which sulphite acts as a ligand for Hg complexes as well as a reducing agent,depending on the existing ***,in the presence of halides,the role of sulphite was less significant.

关键词： flue-gas cleaning flue-gas desulphurization mercury re-emission sulphite measurement

Biodiversity effects and transgressive overyielding

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Journal of Plant Ecology 2008年第2期1卷 95-102页

作者： Bernhard schmid Andy Hector Prasenjit Saha Michel Loreau Institute of Environmental Sciences University of ZurichWinterthurerstrasse 190CH-8057 ZurichSwitzerland Physics Institute University of ZurichWinterthurerstrasse 190CH-8057 ZurichSwitzerland Department of Biology McGill University1205 ave Docteur PenfieldMontrealQuebecCanada H3A 1B1

Aims The potential for mixtures of plant species to produce more biomass than every one of their constituent species in monoculture is still controversially discussed in the *** we tested how this socalled transgressive overyielding is affected by variation between and within species in monoculture yields in biodiversity *** We use basic statistical principles to calculate expected maximum monoculture yield in a species pool used for a biodiversity *** a real example we show how between-and withinspecies variance components in monoculture yields can be *** the two components we estimate the importance of sampling bias in transgressive overyielding *** Findings The net biodiversity effect(difference between mixture and average monoculture yield)needed to achieve transgressive overyielding increases with the number of species in a mixture and with the variation between constituent species in monoculture *** there is no significant variation between species,transgressive overyielding should not be calculated using the best monoculture,because in this case the difference between this species and the other species could exclusively reflect a sampling *** sampling bias decreases with increasing variation between *** for transgressive overyielding require replicated species’***,it can be doubted whether such an emphasis on monocultures in biodiversity experiments is justified if an analysis of transgressive overyielding is not the major goal.

关键词： biodiversity experiments mixtures monocultures overyielding analysis sampling bias

Seasonal characteristics and determinants of tree growth in a Chinese subtropical forest

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Journal of Plant Ecology 2017年第1期10卷 4-12页

作者： Xiulian Chi Qiang Guo Jingyun Fang Bernhard schmid Zhiyao Tang Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface ProcessesPeking UniversityNo.5 Yiheyuan RoadHaidian DistrictBeijing 100871China National Resource Center for Chinese Materia Medica China Academy of Chinese Medical SciencesNo.16 NanxiaojieDongzhimennei AveneDongcheng DistrictBeijing 100700China Institute of Evolutionary Biology and Environmental Studies University of ZürichWinterthurerstrasse 190Zürich 8057Switzerland

Aims To quantify the seasonal differences in effects of leaf habit,species identity,initial diameter,neighborhood interaction and stand environment on tree absolute diameter growth rates in a subtropical forest in *** We used man-made dendrometer bands to record radial increments of all trees with diameter at breast height(DBH)≥5 cm and height≥3 m within 25 comparative study plots(30×30 m for each)of the‘Biodiversity-Ecosystem Functioning Experiment China’(BEF-China)in the Gutianshan National Nature Reserve,Zhejiang Province,*** measured stem circumferences twice a year from 2011 to 2014 to calculate absolute diameter growth rate of a warm and wet season(WWS,April to September)and a dry and cold season(DCS,October to the next March)for each individual tree:annual growth(GR_(year)),growth during the WWS(GR_(WWS))and growth during the DCS(GR_(DCS)).We firstly tested the differences in growth rates between different seasons using paired t-tests with Bonferroni *** we applied linear mixed models to explore the effects of leaf habit,species identity,initial diameter,neighborhood interaction(indicated by richness,density and total basal area of all neighboring trees within a radius of 5 m around target trees),stand age and topography(elevation,slope and aspect)on tree growth rates of the two different seasons in three deciduous and 14 evergreen *** Findings GR_(year),GR_(WWS)and GR_(DCS)varied between 0.04-0.50 cm year^(−1)(mean=0.21),0.03-0.46 cm season^(−1)(mean=0.18)and 0.01-0.05 cm season^(−1)(mean=0.03)across the 17 species,***_(WWS)was significantly higher than GR_(DCS)for all *** rates of faster growing species tended to have larger absolute differences between the WWS and *** growth rates of both seasons and of the year(GR_(year),GR_(WWS)and GR_(DCS))varied significantly among leaf habit and species,and increased allometrically with initial diameter,decreased with stand age,but were not significa

关键词： BEF-China deciduous trees evergreen trees neighborhood interaction species richness

Accuracy of training blood volume quantifi cation using a visual estimation tool

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World Journal of Emergency Medicine 2021年第3期12卷 174-178页

作者： Janett Kreutziger Philip Puchner Stefan schmid Wolfgang Mayer Harald Prossliner Wolfgang Lederer Department of General and Surgical Intensive Care Medicine Medical University of InnsbruckInnsbruck 6020Austria Department of Anesthesiology and Critical Care Medicine Wels-Grieskirchen HospitalWels 4600Austria Department of Transfusion Medicine Medical University of InnsbruckInnsbruck 6020Austria Department of Anaesthesia and Intensive Care Medicine Medical University of InnsbruckInnsbruck 6020Austria

BACKGROUND:We investigated whether the use of a specially designed visual estimation tool may improve accuracy in quantifying blood volumes related to surface ***:A prospective,paired-control,single-blinded experimental study was performed at a medical *** and emergency medical personnel estimated various blood volumes on surfaces with varying absorptivity(carpet,towel,polyvinyl chloride,wooden fl ooring)in an experimental *** assessed the sensitivity of training blood volume quantifi cation using a self-designed visual estimation tool by comparing the accuracy of visual blood volume estimations before and after practical training with the ***:A total of 352 estimations by 44 participants were *** estimations improved significantly from pre-training to post-training(P<0.05).The sensitivity of blood volume quantifi cation was 33.0%after training with the visual estimation *** did not depend on age,profession,gender or years of the estimator’s professional ***:Training with a visual estimation tool by professional rescuers can improve the estimation accuracy of blood volumes spread on surfaces with varying absorptivity.

关键词： Academic training Emergency medicine Hemorrhage control Major bleeding

Comparison of a Reaction Front Model and a Finite Difference Model for the Simulation of Solid Absorption Process

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Journal of Thermal Science 1994年第2期3卷 136-141页

作者： Zikang Wu Arne Jakobsen Xiugan Yuan PWors e-schmid Group 505 Air-Conditioning and Refrigeration InstituteBeijing University of Aeronautics and AstronauticsBeijing 100083China Refrigeration Laboratory The Technical University of DenmarkDK-2800LyngbyDenmark

The purpose of this paper is to investigate the validity of a lumped model, i.e. a reaction front model,for the simulation of solid absorption process. A distributed model is developed for solid absorption process, and a dimensionless RF number is suggested to predict the qualitative shape of reaction degree profile. The simulation results from the reaction front model are compared with those from the distributed model solved by a finite difference scheme, and it is shown that they are in good agreement in almost all casest no matter whether there is reaction front or not.

关键词： solid absorption simulation reaction front RF number reaction degree profile.

Bibliometric analysis of Journal of Plant Ecology during 2017-2021

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Journal of Plant Ecology 2022年第6期15卷 1316-1323页

作者： Pu Wang Lijuan Liu Bi-Cheng Dong Wen-Hao Zhang Bernhard schmid Center for Documentation and Information Institute of BotanyChinese Academy of SciencesBeijing 100093China School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Department of Geography Remote Sensing LaboratoriesUniversity of Zurich8057 ZurichSwitzerland

Journal of Plant Ecology(JPE)was founded in *** is sponsored by the Botanical Society of China and the Institute of Botany,Chinese Academy of Sciences,and published by Oxford University Press,*** publishes diverse types of articles that fall into the broad scope of plant ecology,including plant ecophysiology,population ecology,community ecology,ecosystem ecology,landscape ecology,conservation ecology,evolutionary ecology,theoretical ecology and global change ecology.

关键词： landscape ecology. ecology

The first 10 years of JPE

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Journal of Plant Ecology 2018年第6期11卷 799-802页

作者： Bernhard schmid Pu Wang Lijuan Liu Shiqiang Wan Yao Huang Department of Geography University of ZurichWinterthurerstrasse 190CH-8057 ZurichSwitzerland Institute of Botany Chinese Academy of Sciences20 NanxincunXiangshanBeijing 100093China College of Life Sciences Hebei UniversityNo.180Wusidong RoadBaodingHebei 071002China

Ten years ago,the Botanical Society of China together with the Institute of Botany of the Chinese Academy of Sciences decided to launch the new international Journal of Plant Ecology,or in short JPE,to introduce the works of Chinese ecologists to the international community and promote ecological research in *** new journal,which could be considered as an off-spring of the corresponding Chinese-language journal,offers authors from all over the world,but also specifically from China,a platform to publish peer-reviewed original research and reviews in the broad field of plant *** initial discussions in the editorial board and with Oxford University Press,we decided that it would be best if the authors with their submissions are allowed to define the scope of the journal,because in this way we could gain a unique profile with least overlap with other international *** prime goal was to publish good and relevant science,which would produce long-term impact as a secondary result.

关键词： journal discussions decided