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Quantitative analysis of soil pores under natural vegetation successions on the Loess Plateau

Science china Earth sciences 2010年第4期53卷 617-625页

作者： ZHAO ShiWei1,ZHAO YongGang1,2 & WU JinShui3 1 State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest Agriculture & Forestry university,Yangling 712100,china 2 graduate university of chinese academy of sciences,beijing 1.0049,china 3 Institute of Subtropical Agriculture,chinese academy of sciences,Changsha 410125,china State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Northwest Agriculture & Forestry University Yangling China graduate university of chinese academy of sciences Beijing China Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha China

Soil pore is a key attribute of the soil structure that affects soil reservoir under natural vegetation recovery on the Loess *** study is to quantitatively analyze soil pore parameters,measured with Computed Tomography(CT) at 15-57 mm depths under five different vegetation succession stages using a concept of substituting "space" for "time" in the Ziwuling Forest Region of the Loess *** results showed that the soil pore parameters,such as pore number,porosity,circularity,and fractal dimension,increased significantly under the natural vegetation successions and varied with the pattern climax community stage>pioneering arbor community stage>scrub community stage>herbaceous community stage>abandoned farmland stage,indicating that natural vegetation recovery could remarkably improve soil pore *** the vegetation succession,this positive effect will be strengthened gradually,which means that the soil pore parameters may appear to be best at the climax community *** organic matter content increased linearly with the soil pore parameters(P<0.001).Increased organic matter accumulation was one of the major reasons for the changes in soil pore characteristics in natural vegetation succession.

关键词： Computed Tomography Loess Plateau natural vegetation succession soil pore soil organic matter

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Periodicity of Retzius lines in fossil Pongo from South china

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chinese Science Bulletin 2012年第7期57卷 790-794页

作者： HU Rong1,2,3, ZHAO LingXia1,2 & WU XinZhi2 1 Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, beijing 100044, china 2 Laboratory of Human Evolution, Institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, beijing 100044, china 3 graduate university of chinese academy of sciences, beijing 1.0049, china Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China Laboratory of Human Evolution Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

Periodicity of Retzius lines is a key factor in dental development. In this study, we examined the periodicity of Retzius lines in fossil Pongo from South china using polarized light microscope observation of dental ground sections. The periodicities all of the 15 teeth were 9 d. Comparisons of periodicity were made with extant primates, fossil apes and hominins. Periodicity of fossil Pongo from South china was relatively long but fell within the variation of extant Pongo, Gorilla and modern human, and longer than periodicity of Pan and other extant primates. Fossil Pongo from South china was similar to Lufengpithecus and Sivapithecus, shorter than Gigantopithecus and longer than European and African fossil apes and most early hominins in periodicity. Generally, the periodicities of Asian large-body fossil apes were longer than the periodicities of European and African large-body fossil apes in Miocene. Difference among species and trend of evolution in periodicity were analyzed and discussed. We found that periodicity might gradually increase from Proconsul in early Miocene to several fossil apes in Miocene and then Gigantopithecus in Pleistocene. In addition, this study made correlate analysis between periodicity and body mass respectively in males and females of six extant apes and five fossil apes, and found that periodicity positively correlated with body mass.

关键词：周期性变化中国南方大猩猩化石灵长类动物早中新世类人猿显微镜观察

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Regional soil moisture simulation for Shaanxi Province using SWAT model validation and trend analysis

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Science china Earth sciences 2010年第4期53卷 575-590页

作者： LI MingXing1,2,MA ZhuGuo1 & DU JiWen3 1 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,Institute of Atmospheric Physics,chinese academy of sciences,beijing 100029,china 2 graduate university of chinese academy of sciences,beijing 1.0049,china 3 Shaanxi Administration of Meteorology,Xi’an 710014,china Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China Shaanxi Administration of Meteorology Xi’an China

The soil moisture in Shaanxi Province,a region with complex topography,is simulated using the distributed hydrological model Soil Water Assessment Tool(SWAT).Comparison and contrast of modeled and observed soil moisture show that the SWAT model can reasonably simulate the long-term trend in soil moisture and the spatiotemporal variability of soil moisture in the *** to NCEP/NCAR and ERA40 reanalysis of soil moisture show that the trend of variability in soil moisture simulated by SWAT is more consistent with the *** model results suggested that high soil moisture in surface soil layers appears in the southern Shaanxi with high vegetation cover,and the Qinling mountainous region with frequent orographic *** deeper soil layers,high soil moisture appears in the river basins and *** regional soil moisture showed a generally decreasing trend on all soil layers from 1951 to 2004,with a stronger and significant decreasing trend in deeper soil layers,especially in the northern parts of the province.

关键词： SWAT soil moisture content simulation validation trend analysis

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Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

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chinese Science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2 & TANG XianChun2,3 1 Department of Earth sciences, Nanjing university, Nanjing 210093, china 2 Guangzhou Institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, china 3 graduate university of chinese academy of sciences, beijing 1.0049, china Department of Earth sciences Nanjing University Nanjing China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of chinese academy of sciences Beijing China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩

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A revision of Clematis ***(Ranunculaceae)

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Journal of Systematics and Evolution 2009年第6期47卷 552-580页

作者： ~(1,2)Wen-Jing YANG ~1Liang-Qian LI~* ~3Lei XIE 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,beijing 100093,china) 2(graduate university of chinese academy of sciences,beijing 1.0049,china) 3(Southwestern china Germplasm Bank of Wild Species,Kunming Institute of Botany chinese academy of sciences Kunming 650204,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of chinese academy of sciences Beijing 100049 China) (Southwestern china Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China)

Clematis *** is revised in this paper based on the examination of a large number of herbarium specimens,extensive field observations,and morphometric *** taxonomic history and geographical distribution of the section are given,the relationships among the species are discussed,and the evolutionary trends of some characters in the section are *** staminodes of the plants in this section may have evolved from the outer stamens with petaloid filaments and gradually disappearing ***,they may have evolved in two different *** possibility is that the staminodes elongate and become lanceolate,as long as sepals,and their apices turn into *** other is that the staminodes are spathulate,but not elongating,as long as stamens,and their apices turn into retuse from obtuse and *** evolutionary trend of sepals may be from thin to thick in texture,and the veins from non-prominent to *** a result,five new series are established and nine species, two subspecies and nine varieties(including three new ranks) are recognized in this *** identification key is provided,and each taxon is described and *** sibirica and Clematis ochotensis are treated as subspecies of Clematis alpina due to their subtle differences and lack of,or few,overlapping *** fusijamana and Clematisfauriei are recognized as varieties of *** *** for the continuous variation of the velutinous strips on the sepal *** iliensis is treated as variety of *** *** for the continuous variation of leaf division *** variations in sepal color and basal caruncle size support degrading Clematis chiisanensis as a variety of Clematis *** North American *** may be primitive,whereas *** may be the most advanced taxon in this *** and *** are closely related to each ***,the systematic position of se

关键词： Clematis sect.Atragene Ranunculaceae taxonomic revision

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Intrafloral differentiation of stamens in heterantherous flowers

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Journal of Systematics and Evolution 2009年第1期47卷 43-56页

作者： 1,2Zhong-Lai LUO 1,2Lei GU 1Dian-Xiang ZHANG 1(South china Botanical Garden, chinese academy of sciences, Guangzhou 510650, china) 2(graduate university of chinese academy of sciences, beijing 1.0049, china) South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China graduate university of chinese academy of sciences Beijing 100049 China

Flowers that have heteromorphic stamens (heterantherous flowers) have intrigued many researchers ever since the phenomenon was discovered in the 19th century. The morphological differentiation in androecia has been suggested as a reflection of "labor division" in pollination in which one type of stamens attracts pollinators and satisfies their demand for pollen as food and the other satisfies the plant’s need for safe gamete dispersal. The extent and patterns of stamen differentiation differ notably among taxa with heterantherous flowers. Seven species with heteromorphic stamens in three genera were sampled from Leguminosae and Melastomataceae, and the morphological difference of androecia, pollen content, pollen histochemistry and viability, pollen micro-morphology, as well as the main pollinators were examined and compared. Pollen number differs significantly between stamen sets of the same flower in most species investigated, and a correlation of pollen number and anther size was substantiated. Higher pollen viabilities were found in the long (pollinating) stamens of Senna alata (L.) Roxb. and S. bicapsularis (L.) Roxb. Dimorphic pollen exine ornamentation is reported here for the first time in Fordiophyton faberi Stapf. The height of stigma and anther tips of the long stamens in natural conditions was proved to be highly correlated, supporting the hypothesis that they contact similar areas of the pollinator’s body.

关键词： buzz pollination heteranthery labor division pollen micro-morphology pollen number pollination stamen differentiation

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Bio-regeneration of p-complexation desulfurization adsorbents

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Science china Chemistry 2005年第6期48卷 538-544页

作者： LI Wangliang1,2, XING Jianmin1, XIONG Xiaochao1,2, SHAN Guobin1,2 & LIU Huizhou1 1. Laboratory of Separation Science and Engineering, Institute of Process Engineering, chinese academy of sciences, beijing 100080, china 2. graduate School of the chinese academy of sciences,beijing 100039, china Laboratory of Separation Science and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing China graduate School of the chinese academy of sciences Beijing China

The coupling of adsorption desulfurization and biodesulfurization is a new approach to produce clean fuels. Sulfur compounds are firstly adsorbed on adsorbents, and then the ad-sorbents are regenerated by microbial conversion. p-Complexation adsorbent, Cu(I)-Y, was ob-tained by ion exchanging Y-type zeolite with Cu2+ and then by auto-reduction in helium at 450℃ for 3 h. Dibenzothiophene (DBT) was used as a model compound. The effects of cell concentra-tion, volume of oil phase, the ratio of aqueous phase to adsorbent on DBT desorption by a bac-terium were studied. The amounts of DBT desorbed and 2-HBP produced can be apparently increased with addition of n-octane. BDS activity can be improved by increasing cell concentra-tion and the ratio of water-to-adsorbent. 89% of DBT desorbed from the adsorbents can be converted to 2-HBP within 6 h and almost 100% within 24 h, when the volume ratio of oil-to-water was 1/5 mL/mL, the cell concentration was 60 g·L?1, and the ratio of adsorbent-to-oil was 0.03 g·mL?1. The amount of 2-HBP produced was strongly dependent on the volume ratio of oil-to- water, cell concentration and amount of adsorbent. Adsorption capacity of the regenerated ad-sorbent is 95% that of the fresh one after being desorbed with Pseudomonas delafieldii R-8, washed with n-octane, dried at 100℃ for 24 h and auto-reduced in He.

关键词： adsorption desulfurization p-complexation adsorbents bio-regeneration Pseudomonas delafieldii desorption.

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Explicit analytical solutions of the anisotropic Brinkman model for the natural convection in porous media(Ⅱ)

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 422-430页

作者： CAI Ruixian1, GOU Chenhua1, 2 & ZHANG Na1 1. Institute of Engineering Thermophysics, chinese academy of sciences, beijing 100080, china 2. graduate School, chinese academy of sciences, beijing 100080, china Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China graduate School Chinese Academy of Sciences Beijing China

Some algebraically explicit analytical solutions are derived for the anisotropic Brinkman model―an improved Darcy model―describing the natural convection in porous media. Besides their important theoretical meaning (for example, in analyzing the non-Darcy and anisotropic effects on the convection), such analytical solutions can be the benchmark solutions that can promote the development of computational heat and mass transfer. Some solutions considering the anisotropic effect of permeability have been given previously by the authors, and this paper gives solutions including the anisotropic effect of thermal conductivity and the effect of heat sources.

关键词： explicit analytical solution, porous medium, natural convection, Brinkman model, anisotropic.

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A puzzle of the radio-quiet quasar PG 1407+265:Are optical and X-ray emissions produced from a relativistic jet?

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Science china(Physics,Mechanics & Astronomy) 2011年第1期54卷 183-186页

作者： CHEN Liang 1,2,3 & BAI JinMing 1,2 1 National Astronomical Observatories/Yunnan Observatory,chinese academy of sciences,Kunming 650011,china 2 Key Laboratory for the Structure and Evolution of Celestial Objects,chinese academy of sciences,Kunming 650011,china 3 graduate university of chinese academy of sciences,beijing 1.0049,china National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming China graduate university of chinese academy of sciences Beijing China

PG 1407+265 is a radio quiet quasar that has a relativistic *** this report,we show some peculiar properties of its optical and X-ray emissions,which indicate possible non-thermal origins produced from the *** use a simple synchrotron + synchrotron self Compton (SSC) model to fit the emissions with different ratios of energy densities between the magnetic field and electrons (η≡U B/U e),which predicts a different γ-ray *** First LAT AGN Catalog (1LAC) did not include PG 1407+265,which indicates an upper limit of γ-ray *** upper limit constrains the ratio to be unreasonably large (η≥10 4-5).This inversely indicates that the optical and X-ray emissions may not be produced from the beaming *** discuss the physical implications of these results.

关键词： active galactic nuclei jet non-thermal emission PG 1407+265

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Structures and physical properties of rigid polyurethane foams with water as the sole blowing agent

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Science china Chemistry 2006年第4期49卷 363-370页

作者： LI Xiaobin1,2, CAO Hongbin1 & ZHANG Yi1 1. Institute of Process Engineering, chinese academy of sciences, beijing 100080, china 2. graduate School of the chinese academy of sciences, beijing 100039, china Institute of Process Engineering Chinese Academy of Sciences Beijing China graduate School of the chinese academy of sciences Beijing China

Rigid polyurethane foams blown by varying water level were prepared in this study. The structures and physical properties of rigid polyurethane foams blown by water were measured with FT-IR, universal testing machine (Instron3365), scanning electron microscope (SEM) and differential scanning calorimeter (DSC). The results show that polyurea and polybiuret were the typical charac- teristics, and the cream time and gel time were shorter for the fully water blown rigid foams than that for the fully cyclopentane blown foams. The density of foam samples decreased from 45.0 kg/m3 to 27.4 kg/m3 with the increase of water level from 3 pph to 7 pph. Compressive strength exhibited the similar behavior with density. The average cell size of foam samples ranged from 241 μm to 356 μm with the increase of water level from 3 pph to 7 pph, respectively. At the same time, poorer dimen- sional stability was encountered with the increase of average cell size due to fast diffusion rate of CO2 out of the foam. The results of thermal analysis show that the glass transition temperature (Tg) shifted to a higher temperature with the increase of isocyanate level when more water was used as chemical blowing agent.

关键词： polyether polyol, polyurethane rigid foam, compressive strength, dimensional stability, cell size, glass transition temperature.

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