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Relative importance of water, energy, and heterogeneity in determining regional pteridophyte and seed plant richness in china

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Journal of Systematics and Evolution 2011年第2期49卷 95-107页

作者： 1,2.3 Sheng-Bin CHEN § 1 Gao-Ming JIANG 3 Zhi-Yun OUYANG 3 Wei-Hua XU 3 Yi XIAO 1 (State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, chinese academy of Sciences, {2. 100093, china) 2.(graduate university of the chinese academy of Sciences, beijing 100049, china) 3 (State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, chinese academy of Sciences, {2. 100085, china) (State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of the {2. academy of Sciences Beijing 100049 China) (State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China)

Environmental variables, such as ambient energy, water availability, and environmental heterogeneity have been frequently proposed to account for species diversity gradients. How taxon-specific functional traits define large-scale richness gradients is a fundamental issue in understanding spatial patterns of species diversity, but has not been well documented. Using a large dataset on the regional flora from china, we examine the contrast spatial patterns and environmental determinants between pteridophytes and seed plants which differ in dispersal capacity and environmental requirements. Pteridophyte richness shows more pronounced spatial variation and stronger environmental associations than seed plant richness. Water availability generally accounts for more spatial variance in species richness of pteridophytes and seed plants than energy and heterogeneity do, especially for pteridophytes which have high dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a higher proportion of pteridophytes in regional vascular plant floras (pteridophyte proportion) in wet regions. Most of the variance in seed plant richness, pteridophyte richness, and pteridophyte proportion explained by energy is included in variation that water and heterogeneity account for, indicating the redundancy of energy in the study extent. However, heterogeneity is more important for determining seed plant distributions. Pteridophyte and seed plant richness is strongly correlated, even after the environmental effects have been removed, implying functional linkages between them. Our study highlights the importance of incorporating biological traits of different taxonomic groups into the studies of macroecology and global change biology.

关键词： habitat heterogeneity pteridophytes seed plants species richness water-energy hypothesis.

Validation of three infiltration models on purple soil under simulated rainfall

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Progress in Natural Science:Materials International 2007年第9期17卷 1059-1066页

作者： Wang Yukuan1,2.Fu Bin1,3,Xu Pei1,2.Wang Daojie1,2.Wang Xiantuo1,3 and Wang Yongqiang1,3(1.Key Laboratory of Mountain Surface Process and Hazards,chinese academy of Seiences,Chengdu 610041,{2. 2.Institute of Mountain Hazards and Environment,chinese academy of Sciences,Chengdu 610041,{2. 3.graduate university of the chinese academy of Sciences,beijing 100049,{2.) Key Laboratory of Mountain Surface Process and Hazards Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China graduate university of the {2. academy of Sciences Beijing 100049 China

So as to find models suitable for the prediction of water infiltration in purple soil,infiltration rates simulated by three popular empirical infiltration models,Horton model,Kostiakov model,and the modified Kostiakov model,were compared by using those observed results on slope in purple soil under rainfall simulation.2. sets of infiltration data were divided into two parts for parameter estimation and validation *** performance of the three infiltration models was evaluated with the Nash and Sutcliffe efficiency *** results show that the percent for Nash and Sutcliffe efficiency greater than 0.7 is about 69.7% for the Horton model,and 48.48%,and 54.55% for the Kostiakov model and the modified Kostiakov model,*** model is better than Kostiakov model and the modified Kostiakov model in most rain events in the ***,Kostiakov model is still suitable for reasonable prediction of the infiltration in purple soil sloping farmland because fewer parameters are ***,rainfall intensity has significant effects on the parameter values used in the simulation *** simulation results can be improved by choosing suitable parameters according to the rainfall intensity.

关键词： infiltration model sloping farmland purple soil rainfall simulation

Genesis of ^(2.0)Th excess in basalts from mid-ocean ridges and ocean islands:Constraints from the global U-series isotope database and major and rare earth element geochemistry

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Science china Earth Sciences 2010年第10期53卷 1486-1494页

作者： ZHANG GuoLiang1,2.& ZENG ZhiGang1 1 Key Laboratory of Marine Geology and Environment,Institute of Oceanology,chinese academy of Sciences,Qingdao 2.6071,{2. 2.graduate university of chinese academy of Sciences,beijing 100049,{2. Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao China graduate university of {2. academy of Sciences Beijing China

Based on 2.0Th-2.8U disequilibrium and major element data from mid-ocean ridge basalts(MORBs) and ocean island basalts(OIBs),this study calculates mantle melting parameters,and thereby investigates the origin of 2.0Th excess.(2.0Th/2.8U) in global MORBs shows a positive correlation with Fe8,Po,Na8,and Fmelt(Fe8 and Na8 are FeO and Na2. contents respectively after correction for crustal fractionation relative to MgO = 8 wt%,Po=pressure of initial melting and Fmelt=degree of melt),while 2.0Th excess in OIBs has no obvious correlation with either initial mantle melting depth or the average degree of mantle ***,compared with the MORBs,higher(2.0Th/2.8U) in OIBs actually corresponds to a lower melting *** suggests that the 2.0Th excess in MORBs is controlled by mantle melting conditions,while the 2.0Th excess in OIBs is more likely related to the deep garnet *** vast majority of calculated initial melting pressures of MORBs with excess 2.0Th are between 1.0 and 2.5 GPa,which is consistent with the conclusion from experiments in recent years that DU>DTh for Al-clinopyroxene at pressures of >1.0 *** initial melting pressure of OIBs is 2.2.3.5 GPa(around the spinel-garnet transition zone),with their low excess 2.6Ra compared to MORBs also suggesting a deeper mantle ***,excess 2.0Th in MORBs and OIBs may be formed respectively in the spinel and garnet stability *** addition,there is no obvious correlation of K2./TiO2.with(2.0Th/2.8U) and initial melting pressure(Po) of MORBs,so it is proposed that the melting depth producing excess 2.0Th does not tap the spinel-garnet transition *** and MORBs in both(2.0Th/2.8U) vs.K2./TiO2.and(2.0Th/2.8U) *** plots fall in two distinct areas,indicating that the mineral phases which dominate their excess 2.0Th are ***/Yb-Ce curves of fast and slow ridge MORBs are similar,while,in comparison,the Ce/Yb-Ce curve for OIBs shows more influence from *** mechanism

关键词： excess 2.0Th clinopyroxene garnet spinel-lherzolite mid-ocean ridge ocean island

Review on the study of entanglement in quantum computation speedup

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chinese Science Bulletin 2007年第16期52卷 2161-2166页

作者： DING ShengChao1,3 & JIN Zhi1,2.1 Institute of Computing Technology,chinese academy of Sciences,{2. 100080,china 2.academy of Mathematics and Systems Science,chinese academy of Sciences,{2. 100080,china 3.graduate university of chinese academy of Sciences,{2. 100080,china Institute of Computing Technology Chinese Academy of Sciences Beijing China graduate university of {2. academy of Sciences Beijing China academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

The role the quantum entanglement plays in quantum computation speedup has been widely disputed. Some believe that quantum computation's speedup over classical computation is impossible if entan-glement is absent,while others claim that the presence of entanglement is not a necessary condition for some quantum algorithms. This paper discusses this problem systematically. Simulating quantum computation with classical resources is analyzed and entanglement in known algorithms is reviewed. It is concluded that the presence of entanglement is a necessary but not sufficient condition in the pure state or pseudo-pure state quantum computation speedup. The case with the mixed state remains open. Further work on quantum computation will benefit from the presented results.

关键词：量子论量子纠缠量子计算加速模拟

Confirmation of a natural hybrid species in Petrocosmea(Gesneriaceae) based on molecular and morphological evidence

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Journal of Systematics and Evolution 2011年第5期49卷 449-463页

作者： 1,3~Zhi-Jing QIU 2.Zu-Li YUAN 1~Zhen-Yu LI 1~Yin-Zheng WANG 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of Sciences,{2. 100093,china) 2.Henan Agricultural university,Zhengzhou 45002.china) 3.graduate School of the chinese academy of Sciences,{2. 100049,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate School of the chinese {2. of Sciences Beijing 100049 China) (Henan Agricultural university Zhengzhou 45002 China)

A natural hybrid species in Petrocosmea named Longianthera in Yanshan County,Yunnan Province is confirmed for the first time based on molecular and morphological *** character count procedure of the variable characters show that Longianthera populations are characteristic of the intermediate morphological traits between its putative parents Yanshan and Petrocosmea *** nuclear ribosomal internal transcribed spacer region and three chloroplast regions of matK,trnL-F,and trnT-L are sequenced in the putative hybrid and the related *** alignment of DNA sequences and the phylogenetic trees could exclude all the other species in Petrocosmea as the parental species except for Yanshan and *** haplotypes in the 31 internal transcribed spacer sequences and six haplotypes in 42.cpDNA sequences were found from 14 individuals of Longianthera *** analyses of DNA sequences,haplotypes,and phylogenetic trees indicate that Longianthera is likely a hybrid species between its putative parents Yanshan and ***,in which Yanshan might be the most possible maternal *** factors may contribute to the natural hybridization between these two parental species in Petrocosmea,such as the overlapped geographic distribution,habitats,flowering periods,and shared ***,the new species of Yanshan and the natural hybrid species of Longianthera are described.

关键词： chloroplast DNA Gesneriaceae ITS morphology natural hybridization Petrocosmea.

Pollen limitation and variation in floral longevity in gynodioecious Potentilla tanacetifolia

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Journal of Systematics and Evolution 2011年第6期49卷 539-545页

作者： 1,2.ong YAO 1Yi-Bo LUO 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of Sciences,{2. 100093,china) 2.graduate university of the chinese academy of Sciences,{2. 100049,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of the {2. academy of Sciences Beijing 100049 China)

Pollination limitation is common in flowering plants and is thought to be a factor driving the evolution of floral *** plasticity of floral longevity to pollination may be an adaptation of plants to pollen ***,this adaptation is less critical in short-lived *** evaluate pollen limitation and the plasticity of floral longevity to pollination in Potentilla tanacetifolia,a gynodioecious herb with short-lived flowers,we analyzed its breeding system,tested sex-differential pollen limitation,and compared variations in floral display size in natural populations in Duolun County,Inner Mongolia,*** pollination experiments and pollinator exclusion treatments revealed that *** is self-compatible and non-autonomously apomictic and shows sex-differential pollen *** plasticity of floral longevity to pollination was observed;the floral duration of female plants was prolonged by approximately 3-4 hours with pollination exclusion ***,the percentage of flowers displayed on female plants during pollination exclusion treatment was significantly higher than that during natural *** natural pollination conditions,the percentage of flowers displayed on female plants was significantly higher than on hermaphrodite ***,approximately 50%of the pollen grains spread out of the anthers of hermaphrodite flowers within 2.h of anthesis;the number of pollen grains adhering to the stigmas of hermaphrodite flowers was significantly higher than that adhering to female flowers when flowers shed their *** results indicate that variation in floral longevity may be an adaptive strategy to pollination conditions for gynodioecious ***.

关键词： floral longevity gynodioecy plasticity pollen limitation Potentilla tanacetifolia.

Comparative study of pollination biology of two closely related alpine Primula species,namely Primula beesiana and *** (Primulaceae)

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Journal of Systematics and Evolution 2010年第2期48卷 109-117页

作者： 1,2.hi-Kun WU 1Chang-Qin ZHANG 1(Kunming Institute of Botany,chinese academy of Sciences,Kunming 6502.4,{2.) 2.graduate School of chinese academy of Sciences,beijing 100049,{2.) (Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (graduate School of chinese {2. of Sciences Beijing 100049 China)

The comparative pollination biology of a population of Primula beesiana,a population of ***,and an overlapping population of these two species in Yulong Shan,Yunnan Province,china,was studied in 2.04 and *** results indicate that both *** and *** are typical heterostylous and obligate outcrossing species;the main pollinators of the two species were bees and *** the sites of all three populations,the main pollinating visitors of the two species showed preference for one of the two species,resulting in the ethological isolation of the two species by the *** ethological isolation contributes to the reproductive isolation of the two species,which supports the hypothesis that *** and *** are two distinct *** reproductive isolation of the two species (ethological isolation) is probably an important mechanism in maintaining species boundaries in the genus and has contributed to the species diversification of Primula in the *** addition,gene exchanges between *** and *** has occurred to some extent in the overlapping population,but whether natural hybridization has contributed to species diversification in Primula remains to be determined.

关键词： pollination biology Primula beesiana Primula bulleyana reproductive isolation

Autonomous satellite constellation orbit determination using the star sensor and inter-satellite links data

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 966-974页

作者： GAN QingBo1,2.MA JianBo1 & XU Jin1 1 Purple Mountain Observatory,chinese academy of Sciences,Nanjing 2.0008,{2. 2.graduate university of chinese academy of Sciences,beijing 100049,{2. Purple Mountain Observatory Chinese Academy of Sciences Nanjing China graduate university of {2. academy of Sciences Beijing China

A method of autonomous orbit determination for a satellite constellation using a star sensor combined with inter satellite links(ISLs) is *** types of simulated observation data,Three-Satellite Constellation ISLs and background stellar observations by a CCD star sensor,are first *** on these data,an observation equation is built for the constellation joint autonomous orbit determination,in which the simulations are *** accuracy of this method with different orbital determination models are analyzed and compared with regard to the effect of potential measurement *** results show that autonomous satellite constellation orbit determination using star sensor measurement and ISLs data is ***,this paper arrives at several conclusions which contribute to extending this method to a more general satellite constellation.

关键词： satellite constellation star sensor inter-satellite links autonomous orbit determination

Validating global hydrological models by ground and space gravimetry

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chinese Science Bulletin 2009年第9期54卷 1534-1542页

作者： ZHOU JiangCun1,2.3, SUN HePing1,2.& XU JianQiao1,2.1 Institute of Geodesy and Geophysics, chinese academy of Sciences, Wuhan 430077,{2. 2.Key Laboratory of dynamic geodesy, chinese academy of Sciences, Wuhan 430077,{2. 3.graduate university of chinese academy of Sciences, beijing 100049,{2. Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China Key Laboratory of dynamic geodesy Chinese Academy of Sciences Wuhan China graduate university of {2. academy of Sciences Beijing China

The long-term continuous gravity observations obtained by the superconducting gravimeters (SG) at seven globally-distributed stations are comprehensively analyzed. After removing the signals related to the Earth's tides and variations in the Earth's rotation, the gravity residuals are used to describe the seasonal fluctuations in gravity field. Meanwhile, the gravity changes due to the air pressure loading are theoretically modeled from the measurements of the local air pressure, and those due to land water and nontidal ocean loading are also calculated according to the corresponding numerical models. The numerical results show that the gravity changes due to both the air pressure and land water loading are as large as 100×10-9 m s-2.in magnitude, and about 10×10-9 m s-2.for those due to the nontidal ocean loading in the coastal area. On the other hand, the monthly-averaged gravity variations over the area surrounding the stations are derived from the spherical harmonic coefficients of the GRACE-recovered gravity fields, by using Gaussian smoothing technique in which the radius is set to be 600 km. Com-pared the land water induced gravity variations, the SG observations after removal of tides, polar mo-tion effects, air pressure and nontidal ocean loading effects and the GRACE-derived gravity variations with each other, it is inferred that both the ground- and space-based gravity observations can effec-tively detect the seasonal gravity variations with a magnitude of 100×10-9 m s-2.induced by the land water loading. This implies that high precision gravimetry is an effective technique to validate the re-liabilities of the hydrological models.

关键词：重力测量水文模型模型验证和空间地面重力变化季节性波动空气压力