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Journal of Social Computing 2022年第1期3卷 38-56页

作者： Laura J.Ellyson the Department of Anthropology Washington State UniversityPullmanWA 99163USA terrestrial archaeology division SEARCH Inc.PensacolaFL 32503USA.

Although Gregory Johnson’s models have influenced social theory in archaeology,few have applied or built upon these models to predict aspects of social organization,group size,or *** have been limited to small case ***,the relationship between a society’s scale and its information-processing capacities has been explored using the Seshat ***,I apply multiple-linear regression analysis to the Seshat data using Turchin and colleagues’9“complexity characteristics”(CCs)to further examine the relationship between the hierarchy CC and the remaining 8 CCs which include both aspects of a polity’s scale and aspects of what Kohler et ***“collective computation”.The results support Johnson’s ideas that stratification will generally increase with increases in a polity’s scale(population,territory);however,stratification is also higher when polities increase their developments in information-processing variables such as texts.

关键词： hierarchy scalar stress Seshat Databank multiple imputation multiple regression

Influence of Soil Properties on Zinc Solubility Dynamics Under Different Redox Conditions in Non-Calcareous Soils

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Pedosphere 2017年第1期27卷 96-105页

作者： Michelle Anne Belen BUNQUIN Susan TANDY Sarah Johnson BEEBOUT Rainer SCHULIN Crop and Environmental Sciences division International Rice Research InstituteCollegeLos Banos Soil Protection Institute of Terrestrial EcosystemsETH Zurich

Zinc(Zn) deficiency in paddy soils is often a problem for rice *** can decrease metal availability in some noncalcareous soils through different mechanisms associated with soil redox *** experiments were performed in order to better understand the processes that governed the dynamics of Zn in non-calcareous paddy soils at varying redox potentials(Eh).Airdried non-calcareous soil samples collected from four different paddy field sites in the Philippines were submerged and incubated in a reaction cell with continuous stirring and nitrogen purging for 4 weeks,and then purged with compressed air for another week to reoxidize the *** Eh of the four soils started at 120 to 300 mV,decreased to —220 to —300 mV after 100 to 250 h of reduction,and was maintained at this low plateau for about 2 weeks before increasing again upon *** solubility showed contrasting patterns in the four soils,with two of the soils showing a decrease in soluble Zn as the Eh became low,probably due to zinc sulfide(ZnS) *** contrast,the other two soils showed that Zn solubility was maintained during the reduced phase which could be due to the competition with iron(Fe) for precipitation with *** in the relative amounts of S,Fe,and manganese(Mn) oxides in the four soils apparently influenced the pattern of Zn solubility after flooding.

关键词： microcosm paddy soil precipitation rice soil sulfide speciation Zn availability

Anisotropic Beam Model for the Spectral Observations of Radio Burst Fine Structures on 1998 April 15

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Chinese Journal of Astronomy and Astrophysics 2001年第5期1卷 475-482页

作者： V.G. LedenevE-mail:yyh@*** , Yi-Hua Yan, and Qi-Jun Fu (National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012) (Institute of Solar-terrestrial Physics, Siberian division of Russian Academy of Sciences 664033, Irkutsk, P. 0 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 Institute of Solar-terrestrial Physics Siberian Division of Russian Academy of Sciences 664033 Irkutsk P. O. Box 4026 Russia

A fine structure consisting of three almost equidistant frequency bands was observed in the high frequency part of a solar burst on 1998 April 15 by the spectrometer of Beijing Astronomical Observatory in the range 2.6-3.8 GHz. A model for this event based on beam-anisotropic instability in the solar corona is presented. Longitudinal plasma waves are excited at cyclotron resonance and then transformed into radio emission at their second harmonic. The model is in accordance with the observations if we suppose a magnetic field strength in the region of emission generation of about 200 G.

关键词： Sun: radio radiation Sun: activity - Sun: corona

Improvements of a Dynamic Global Vegetation Model and Simulations of Carbon and Water at an Upland-Oak Forest

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Advances in Atmospheric Sciences 2007年第2期24卷 311-322页

作者：毛嘉富王斌戴永久 F.I.WOODWARD P.J.HANSON M.R.LOMAS State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences School of Geography Beijing Normal University Centre for terrestrial Carbon Dynamics and Department of Animal and Plant Sciences University of Sheffield UK Environmental Sciences division Oak Ridge National Laboratory P.O.Box 2008Oak RidgeTennessee 37831-6422US

The interest in the development and improvement of dynamic global vegetation models （DGVMs）, which have the potential to simulate fluxes of carbon, water and nitrogen, along with changes in the vegetation dynamics, within an integrated system, has been increasing. In this paper, some numerical schemes and a higher resolution soil texture dataset were employed to improve the Sheffield Dynamic Global Vegetation Model （SDGVM）. Using eddy covariance-based measurements, we then tested the standard version of the SDGVM and the modified version of the SDGVM. Detailed observations of daily carbon and water fluxes made at the upland oak forest on the Walker Branch Watershed in Tennessee, USA offered a unique opportunity for these comparisons. The results revealed that the modified version of the SDGVM did a reasonable job of simulating the carbon and water flux and the variation of soil water content （SWC）. However, at the end of the growing season, it failed to simulate the effect of the limitations on the soil respiration dynamics and as a result underestimated this respiration. It was also noted that the modified version overestimated the increase in the SWC following summer rainfall, which was attributed to an inadequate representation of the ground water and thermal cycle.

关键词： dynamic global vegetation models terrestrial carbon and water fluxes Eddy covariance calibration

Exogenous nitrogen input skews estimates of microbial nitrogen use efficiency by ecoenzymatic stoichiometry

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Ecological Processes 2023年第1期12卷 625-631页

作者： Lifei Sun Daryl L.Moorhead Yongxing Cui Wolfgang Wanek Shuailin Li Chao Wang CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Environmental Sciences University of ToledoToledo 43606USA Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100871China division of terrestrial Ecosystem Research Center of Microbiology and Environmental Systems ScienceUniversity of ViennaDjerassiplatz 11030 ViennaAustria

Background Ecoenzymatic stoichiometry models(EEST)are often used to evaluate microbial nutrient use efficiency,but the validity of these models under exogenous nitrogen(N)input has never been ***,we investigated the effects of long-term N addition(as urea)on microbial N use efficiency(NUE),compared EEST and^(18)O-labeling methods for determining NUE,and evaluated EEST’s theoretical assumption that the ratios of standard ecoenzymatic activities balance resource availability with microbial *** We found that NUE estimated by EEST ranged from 0.94 to *** contrast,estimates of NUE by the^(18)O-labeling method ranged from 0.07 to *** large differences in NUE values estimated by the two methods may be because the sum ofβ-N-acetylglucosaminidase and leucine aminopeptidase activities in the EEST model was not limited to microbial N acquisition under exogenous N inputs,resulting in an overestimation of microbial NUE by *** addition,the acquisition of carbon by N-acquiring enzymes also likely interferes with the evaluation of NUE by *** Our results demonstrate that caution must be exercised when using EEST to evaluate NUE under exogenous N inputs that may skew standard enzyme assays.

关键词： Extracellular enzyme Resource allocation Nitrogen addition Microbial metabolism limitation Isotope labeling

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Response of the Ionospheric F_2-region Over Irkutsk and Hainan to Strong Geomagnetic Storms

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空间科学学报 2013年第5期33卷 494-500页

作者： E B Romanova G A Zherebtsov K G Ratovsky N M Polekh J K Shi X Wang G J Wang Institute of Solar-terrestrial Physics Siberian BranchRussian Academy of Sciences State Key Laboratory of Space Weather Center for Space Science and Applied ResearchChinese Academy of Sciences

The ionospheric responses to two strong storms on 17-19 August 2003 and 22-23 January 2004 are studied,using the data from Irkutsk(52.5°N,104°E) and Hainan(19.5°N,109°E) ionospheric *** analysis of variations in relative deviations of the critical frequency △f_0F_2 revealed that at middle latitudes(Irkutsk) negative disturbances were observed in the summer ionosphere; positive and negative ones,in the winter ionosphere during the main and recovery phases *** low latitudes(Hainan),the disturbances were positive in all the cases considered. Mechanisms of the disturbances were analyzed with the aid of empirical models of the neutral atmosphere NRLMSISE-00 and thermospheric wind *** main factors determining △f_0F_2 variations at middle latitudes during the storms were demonstrated to be the disturbed equatorward thermospheric wind transporting the disturbed atmospheric composition,the increase in the atomic oxygen concentration,and the passage of internal gravity *** low latitudes,the effects associated with neutral composition variations are less significant than those of the thermospheric wind and electric fields.

关键词： Ionosphere Geomagnetic storm Thermospheric wind Drift

Grasshoppers （Orthoptera： Acrididae） select vegetation patches in local-scale responses to foliar nitrogen but not phosphorus in native grassland

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Insect Science 2011年第5期18卷 533-540页

作者： Viviana Loaiza Jayne L. Jonas Anthony Joern division of Biology Kansas State University Manhattan Kansas USA

Key elements such as nitrogen （N） and phosphorus （P） are often limiting relative to the nutritional needs of herbivores that feed on them. While N often limits insect herbivores in natural terrestrial ecosystems, the effect of P is poorly studied in the field, even though compelling hypotheses from the ecological stoichiometry literature predict its importance. We evaluated small-scale spatial distributions of, and herbivory by, grasshoppers among neighboring plots that vary in foliar-N and -P in tallgrass prairie. Grasshopper densities were 67% greater in N-fertilized plots but detected no effect to grasshopper densities from P-fertilizer. Leaf damage to the dominant grass Andropogon gerardii was 32% greater in N-fertilized plots, but no response to foliar-P was detected. Herbivore damage to a common forb, goldenrod （Solidago missouriensis）, was not strongly linked by fertilizer treatments, although there was increased leaf damage in N-fertilizer treatments when no P was applied （a significant N ~ P interaction）. Under field conditions at local scales, we conclude that spatially heterogeneous distributions of grasshoppers are primarily affected by foliar-N in host plants with little evidence that P-levels contribute to the spatial patterns.

关键词： Andropogon gerardii ecological stoichiometry insect herbivory Konza Prairie N-P fertilization experiment Solidago rnissouriensis

When Fleeing Matters:Differences in Escape Behaviours of Three Northeast Asian Anurans

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Asian Herpetological Research 2024年第1期15卷 41-48页

作者： Yoonjung YI Zoljargal PUREVDORJ Irina MASLOVA Yikweon JANG Amaël BORZÉE Laboratory of Animal Behaviour and Conservation College of Life SciencesNanjing Forestry UniversityNanjing 210037JiangsuChina division of EcoScience and Department of Life Sciences Ewha Womans UniversitySeoul 03760Republic of Korea Department of Biology School of MathematicsMongolian State University of EducationUlaanbaatar 210648Mongolia Department of Forest and Environmental Resources Chungnam National UniversityDaejeon 34134Republic of Korea Federal Scientific Center of the East Asia terrestrial Biodiversity Far Eastern Branch of Russian Academy of SciencesVladivostok 690022Russia

Prey species may have their own optimal escape strategy to balance predation risks and the energetic cost of *** species have an advantage when maintaining a short fleeing distance,while others may favour an earlier escape based on microhabitat,size,or body ***,we examined the escape behaviour of the three syntopic Northeast Asian anuran species:Mongolian toads(Strauchbufo raddei),Amur brown frogs(Rana amurensis),and Japanese treefrogs(Dryophytes japonicus)in Mongolia,Russia,China and DPR *** examined flight initiation distance(FID;the distance from a potential predator to the point when the individual starts to flee)and distance fled(DF;distance between flight initiation and flight termination points)of each species and the effects of microhabitat,sex,and body *** raddei and *** had a longer FID than ***,and *** also had a longer DF than *** trends remained similar when dividing FID and DF by a size proxy(snout-vent length)for all *** suggests that the treefrog *** used a strategy to stay immobile even when they were detected,and the toad *** reacted quicker and more sensitively to predators despite the presence of *** *** had a significantly longer FID than males suggesting that females are more sensitive to predation risk in this species,but body size was not significant for any of the three *** results indicate that the three sympatric species have different escaping strategies,likely related to differences in physiology and crypticity.

关键词： amphibian distance fled escape behaviour flight initiation distance predation

Tree-based ecosystem services supply and multifunctionality of church forests and their agricultural matrix near Lake Tana,Ethiopia

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Forest Ecosystems 2023年第6期10卷 656-667页

作者： Ferehiwot Mequanint Tobias Fremout Diederik Strubbe Alemayehu Wassie Shimelis Aynalem Enyew Adgo Jan Nyssen Amaury Frankl Luc Lens Bart Muys Department of Wildlife and Ecotourism Management Bahir Dar UniversityBahir DarEthiopia terrestrial Ecology Unit Ghent UniversityGhentBelgium division Forest Natureand LandscapeKU LeuvenLeuvenBelgium Alliance Biodiversity International–CIAT LimaPeru Organization for Rehabilitation and Development in Amhara Bahir DarEthiopia Department of Natural Resource Management Bahir Dar UniversityBahir DarEthiopia Department of Geography Ghent UniversityGhentBelgium INRAE AMAPIRDCIRADCNRSUniversity MontpellierBld de La Lironde34398Montpellier Cedex 5France

Ecosystem services(ES)are the connection between nature and society,and are essential for the well-being of local communities that depend on *** Ethiopia,church forests and the surrounding agricultural matrix supply numerous ***,the ES delivered by both land use types have not yet been assessed *** we surveyed both church forests and their agricultural matrices,aiming to quantify,compare and unravel the drivers underlying tree-based ES supply,density and *** found that almost all church forests and half of the agricultural matrices provided high ES *** multifunctionality was higher in the agricultural matrices,suggesting that people deliberately conserve or plant multifunctional tree ***,the supply of all categories of ES was positively correlated with church forest age(p-value<0.001)in the agricultural matrix,while the extent of church forest was positively correlated with the density of all categories ecosystem services score in the church forests(p-value<0.001).Our results can be used to prioritize conservation efforts at sites that provide high levels of ES supply,ES density and ES multifunctionality,and to prioritize restoration efforts at sites with low levels thereof.

关键词： Church forest Remnant forest Provisioning service Regulating service Cultural service Multifunctionality Key informant interview Agricultural matrix

Observations of the step-like accelerating processes of cold ions in the reconnection layer at the dayside magnetopause

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Science Bulletin 2018年第1期63卷 31-37页

作者： Qinghe Zhang Michael Lockwood John C.Foster Qiugang Zong Malcolm W.Dunlop Shunrong Zhang Joran Moen Beichen Zhang Shandong Provincial Key Laboratory of Optical Astronomy and Solar-terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Department of Meteorology University of ReadingReading RG6 6BBUK MIT Haystack Observatory WestfordMA 01886USA School of Earth and Space Sciences Peking UniversityBeijing 100087China Space Sciences division SSTDRutherford Appleton LaboratoryDidcot OX11 OQXUK Department of Physics University of OsloBlindern 0316OsloNorway SOA Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China

Cold ions of plasmaspheric origin have been observed to abundantly appear in the magnetospheric side of the Earth's magnetopause. These cold ions could affect the magnetic reconnection processes at the magnetopause by changing the Alfvén velocity and the reconnection rate, while they could also be heated in the reconnection layer during the ongoing reconnections. We report in situ observations from a partially crossing of a reconnection layer near the subsolar magnetopause. During this crossing, step-like accelerating processes of the cold ions were clearly observed, suggesting that the inflow cold ions may be separately accelerated by the rotation discontinuity and slow shock inside the reconnection layer.

关键词： Cold ions Magnetic reconnection Ion accelerations Magnetopause