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Features and distribution patterns of chinese endemic seed plant species

Journal of Systematics and Evolution 2011年第2期49卷 81-94页

作者： 1,2,3 Ji-Hong HUANG 1,4.Jian-Hua CHEN 5 Jun-Sheng YING 1 Ke-Ping MA 1 (State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, chinese academy of sciences, Beijing 100093, china) 2 ({4. university of chinese academy of sciences, Beijing 10004., china) 3 (Center for Documentation and Information, Institute of Botany, chinese academy of sciences, Beijing 100093, china) 4.(Zhejiang Normal university, Jinhua 321004. china) 5 (Research Center of Systematic and Evolutionary Botany, Institute of Botany, chinese academy of sciences, Beijing 100093, china) (State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of chinese academy of {4. Beijing 100049 China) (Center for Documentation and Information Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Zhejiang Normal university Jinhua 321004 China) (Research Center of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

We compiled and identified a list of chinese endemic seed plant species based on a large number of published references and expert reviews. The characters of these seed plant species and their distribution patterns were described at length. china is rich in endemic seed plants, with a total of 14.939 species (accounting for 52.1% of its total seed plant species) belonging to 1584.genera and 191 families. Temperate families and genera have a significantly higher proportion of endemism than cosmopolitan and tropical ones. The most primitive and derived groups have significantly higher endemism than the other groups. The endemism of tree, shrub, and liana or vine is higher than that of total species; in contrast, the endemism of herb is lower than that of total species. Geographically, these chinese endemic plants are mainly distributed in Yunnan and Sichuan provinces, southwest china. Species richness and proportion of these endemic plants decrease with increased latitude and have a unimodal response to altitude. The peak value of proportion of endemism is at higher altitudes than that of total species and endemic species richness. The proportions of endemic shrub, liana or vine, and herb increase with altitude and have a clear unimodal curve. In contrast, the proportion of tree increases with altitude, with a sudden increase at ～4.00 m and has a completely different model. To date, our study provides the most comprehensive list of chinese endemic seed plant species and their basic composition and distribution features.

关键词： biodiversity conservation distribution pattern endemism flora of china seed plants.

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Evidence from isotopic geochemistry as an indicator of eutrophication of Meiliang Bay in Lake Taihu, china

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Science china Earth sciences 2006年第Z1期49卷 62-71页

作者： LIN Lin, WU Jinglu & WANG Sumin Nanjing Institute of Geography & Limnology, chinese academy of sciences, Nanjing 210008, china {4. university of the chinese academy of sciences, Beijing 100039, china Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing China graduate university of the chinese academy of {4. Beijing China

In this paper, Lake Taihu, a large shallow freshwater lake in china, is chosen as an example of reconstruction of eutrophication through the comparison between stable isotopes from dissolved nutrients and plants and water column nutrient parameters and integration of multiple proxies in a sediment core from Meiliang Bay including TN, TP, TOC, C/N, δ15N, δ13C, etc. Differences in aquatic plant species and trophic status between East Taihu Bay and Meiliang Bay are indicated by their variations in δ13C and δ15N of aquatic plants and δ15N of NH4.. A significant influence ofexternal nutrient inputs on Meiliang Bay is reflected in temporal changes in δ 15N of NH4. and hydro-environmental parameters. The synchronous change between δ13C and δ15N values of sedimented organic matter (OM) has been attributed to elevated primary production at the beginning of eutrophication between 1950 and 1990, then recent inverse correlation between them has been caused by the uptake of 15N-enriched inorganic nitrogen by phytoplankton grown under eutrophication and subsequent OM decomposition and denitrification in surface sediments, indicating that the lake has suffered from progressive eutrophication since 1990. Based on the use of a combination of stable isotopes and elemental geochemistry, the eutrophication of Meiliang Bay in Lake Taihu could be better traced. These transitions of the lake eutrophication respectively occurring in the 1950s and 1990s have been suggested as a reflection of growing impacts of human activities, which is coincident with the instrumental data.

关键词： stable carbon isotope of OM, stable nitrogen isotope, eutrophication, Lake Taihu.

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Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4. HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 2. Department of Urban and Resources sciences, Nanjing university, Nanjing 210093, china 3. Department of Earth sciences, Nanjing university, Nanjing 210093, china 4. Department of Geography, Shaanxi Normal university, Xi’an 710062, china 5. Institute of Geology and Geophysics, chinese academy of sciences, Beijing 100029, china 6 Department of Geography, Qinghai Normal university, Xining 810008, china 7. graduate School of the chinese academy of sciences, Beijing 100039, china SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an China graduate School of the chinese academy of sciences Beijing China Department of Urban and Resources sciences Nanjing University Nanjing China Department of Earth sciences Nanjing University Nanjing China Department of Geography Shaanxi Normal University Xi’an China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Department of Geography Qinghai Normal University Xining China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the chineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4.Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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The gravitational gradient tensor’s invariants and the related boundary conditions

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Science china Earth sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2,3 & ZHAO DongMing4.1 College of Earth Science, graduate university of chinese academy of {4., Beijing 10004., china 2 Institute of Geodesy and Geophysics, chinese academy of {4., Wuhan 4.0077, china 3 State Key Laboratory of Astronautic Dynamics, Xi’an 71004., china 4.Zhengzhou Institute of Surveying and Mapping, Zhengzhou 4.0052, china College of Earth Science Graduate University of Chinese Academy of Sciences Beijing China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China State Key Laboratory of Astronautic Dynamics Xi’an China Zhengzhou Institute of Surveying and Mapping Zhengzhou China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2-term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2/2 T), which is approximately equivalent to O(T2). Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 200, and the models with regard to effect of J2-term have accuracies of 10-8 and the order can reach up to 280.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

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Taxonomic revision of Lepisorus(***.) Ching ***(Polypodiaceae) from china

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Journal of Systematics and Evolution 2009年第6期47卷 581-598页

作者： ~(1,2)Xin-Ping QI ~1Xian-Chun ZHANG~* 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,Beijing 100093,china) 2({4. university of chinese academy of sciences,Beijing 10004.,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 {4. Beijing 100049 China)

The taxonomy of Lepisorus(***.) Ching *** in china was revised based on herbarium specimen examinations,field observations,and microscopic study of rhizome scales,soral paraphyses,leaf epidermis, and *** a result,nine species were recognized:Lepisorus macrosphaerus(Baker) Ching,Lepisorus asterolepis (Baker) Ching,Lepisorus marginatus Ching,Lepisorus kuchenensis(***) Ching,Lepisorus megasorus(***.) Ching,Lepisorus kawakamii(Hayata) Tagawa,Lepisorus subsessilis Ching & ***,Lepisorus affinis Ching, and Lepisorus nudus(Hook.) *** kawakamii(Hayata) Tagawa was reinstated;Lepisorus gyirongensis Ching & *** and Lepisorus longus Ching were reduced to synonyms *** and ***,respectively. The subdivision ofLepisorus macrosphaerus was not *** scales and paraphyses are the most useful characters for species delimitation as well as for infrageneric *** of the leaf epidermis and spore ornamentation are usually stable and thus of great significance in understanding the relationships among groups within the genus.

关键词： china Lepisorus Lepisorus sect.Lepisorus Polypodiaceae taxonomic revision

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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,Beijing 100080,china 2 academy of Mathematics and Systems Science,chinese academy of sciences,Beijing 100080,china 3 graduate university of chinese academy of sciences,Beijing 100080,china Institute of Computing Technology Chinese Academy of Sciences Beijing China graduate university of chinese academy of {4. 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

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The deep thermal characteristic of continental margin of the northern South china Sea

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chinese Science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & WANG Jiyang1. graduate School, university of Science and Technology of china, chinese {4. of sciences, Beijing 100039, china 2. Institute of Geology, chinese {4. of sciences, Beijing 100029, china graduate School University of Science and Technology of China Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South china Sea. The analysis of heat flow value shows that margin heat flow in the northern South china Sea is relatively high setting, but the percentage of crustal heat flow is lower than 35% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South china Sea terrestrial heat flow thermal structures.

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SUSPENDED SEDIMENT TRANSPORT IN THE OFFSHORE NEAR YANGTZE ESTUARY

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Journal of Hydrodynamics 2008年第3期20卷 373-381页

作者： CHEN Bin WANG Kai Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate university of the chinese academy of {4. Beijing 100039 China

Based on the Estuarine, Coastal and Ocean Modeling System with Sediments （ECOMSED） model, a 3-D hydrodynamic-transport numerical model was established for the offshore area near the Yangtze Estuary in the East china Sea .The hydrodynamic module was driven by tide and wind. Sediment module included sediment resuspension, transport and deposition of cohesive and non-cohesive sediment. The settling of cohesive sediment in the water column was modeled as a fimction of aggregation （flocculation） and deposition. The numerical results were compared with observation data for August, 2006. It shows that the sediment concentration reduces gradually from the seashore to the offshore area. Numerical results of concentration time series in the observation stations show two peaks and two valleys, according with the observation data. It is mainly affected by tidal current. The suspended sediment concentration is related to the tidal current during a tidal cycle, and the maximum concentration appears 1 h-4.h after the current maximum velocity has reached.

关键词： Yangtze Estuary sediment concentration sediment transport

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Study on the atmospheric photochemical reaction of CF_3 radicals using ultraviolet photoelectron and photoionization mass spectrometer

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Science china Chemistry 2008年第4期51卷 316-321页

作者： YAO Li1,2, DU Lin1,2, YIN Shi1,2 & GE MaoFa1 1 Beijing National Laboratory for Molecular sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, chinese academy of sciences, Beijing 100080,{4. 2 graduate university of chinese academy of sciences, Beijing 100080,{4. Beijing National Laboratory for Molecular sciences (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing China graduate university of chinese academy of {4. Beijing China

A study of the atmospheric photochemical reaction of CF3 radical with CO and O2 was performed by using a homemade ultraviolet photoelectron spectrometer-photoionization mass spectrometer (PES- PIMS). The electronic structures and mechanism of ionization and dissociation of CF3OC(O)OOC(O)- OCF3 were investigated. It was indicated that the two bands on the photoelectron spectrum of CF3OC(O)OOC(O)OCF3 are the result of ionization of an electron from a lone pair of oxygen and a fluo- rine lone pair of CF3 group. The outermost electrons reside in the oxygen lone pair. The experimental and theoretical first vertical ionization energy is 13.21 and 13.178 eV, respectively, with the PES and OVGF method. They are in good agreement. The photo ionization and dissociation processes were discussed with the help of theoretical calculations and PES-PIMS experiment. After ionization, the parent ions prefer the dissociation of the C-O bond and giving the fragments CF3OCO+ and CF3+. It demonstrated that the ultraviolet photoelectron and photoionization mass spectrometer could be ap- plied widely in the study of atmospheric photochemical reaction.

关键词： photochemical reaction CF3 radical ultraviolet photoelectron and photoionization mass spectroscopy transient species

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Spatial heterogeneity of the driving forces of cropland change in china

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Science china Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2, WANG Jinfeng1, LIU Mingliang4.1 & MENG Bin1,2,3 1. Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101,{4. 2. graduate School of the chinese academy of sciences, Beijing 100039,{4. 3. College of Arts and sciences of Beijing Union university, Beijing 100083,{4. 4. School of Forestry and Wildlife sciences, Auburn university, Auburn, Alabama, AL3684., USA Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate School of the chinese academy of sciences Beijing China School of Forestry and Wildlife sciences Auburn University Auburn Alabama USA College of Arts and sciences of Beijing Union university Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2000 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in china. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of china, natural condition changes and geographical background were the main constraints and drivers, while in Eastern china, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in china recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, china.

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