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Coupling the hydrological and ecological process to implement the sustainable water resources management in Hanjiang River Basin

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science china(Technological sciences) 2009年第11期52卷 3240-3248页

作者： ZHANG Xiang1 & XIA Jun2 1 state key laboratory of Water Resources and Hydropower Engineering science, Wuhan University, Wuhan 430072, china 2 key laboratory of Water Cycle and Related Land Surface Processes, IGSNRR, chinese academy of sciences, beijing 100101, china state key laboratory of Water Resources and Hydropower Engineering science Wuhan University Wuhan China key laboratory of Water Cycle and Related Land Surface Processes IGSNRR Chinese Academy of Sciences Beijing China

Research on the combination of hydrological variation and ecological demands plays an important role in water availability assessment and sustainable management on basin scale. An integrative frame, consisting of hydrological regime modelling, ecological water demands estimation and renewable resources management, is given in this paper in order to support the implementation of the sustainable water resources management. The suggested integrative frame has been used to study the integrated water resources management in southern Hanjiang River Basin which is the water source of South-toNorth Water Transportation Project in china. SWAT (soil and water assessment tool) model was used to simulate the monthly averaging streamflow and the amounts of ecological water demands in stream were also estimated in order to evaluate the available water resources for the local users and the transportation project. Then we formed the developing scenarioes by coupling the available water resources, the recovering rate of water resources in natural water cycle, the local water use rate and the amounts of the water transported to North, and used the Scheafer model to analyze their evolving trajectories. Eventually, the sustainable water resources management measures were assembled by the comprehensive evaluation of the scenarioes. The research indicates that the integrative frame provided a new way for the integrated water resources management in river basin.

关键词： SWAT (soil and water assessment tool) Scheafer model ecological water demands water resources availability sustainable water resources management

Paeonia rotundiloba(***)***:A new status in tree peonies(Paeoniaceae)

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Journal of Systematics and Evolution 2011年第5期49卷 464-467页

作者： De-Yuan HONG(state key laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,beijing 100093,china) (state key laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

Paeonia decomposita Hand.-*** *** is here raised to the specific rank,***(***) ***,based on its distinctiveness of four diagnostic characters:number of carpels;height of disk;number of leaflets of the lower leaves,and shape of the terminal leaflets;and unpublished molecular *** rotundiloba differs distinctly from *** in having carpels mostly 3,less often 2 or 4,very rarely 5(*** always 5,very occasionally 4 or 3),disk 8-15 mm high(vs.4-9.6 mm),leaflets mostly 19-39(vs.29-63) in number,and ratio of length to width of the terminal leaflets 1.09-1.93(vs.1.81-2.99).

关键词： china new status Paeonia decomposita Paeonia rotundiloba Sichuan statistical analysis.

Interdecadal trend turning of global terrestrial temperature and precipitation during 1951-2002

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Progress in Natural science:Materials International 2008年第11期18卷 1383-1393页

作者： Xiaohui Shi Xiangde Xu state key laboratory of Severe Weather,chinese academy of Meteorological sciences,beijing 100081,china state key laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

A grid-by-grid counting of interdecadal trend turning(ITT)of annual mean surface air temperature(SAT)and total precipitation at 67,359 terrestrial grids in the period 1951-2002 is *** analysis of the last ITTs of SAT and total precipitation in the period,in the context of both occurrence time and linear trends after the breakpoint,indicates that a warming trend has become highly significant across most reagent of the world in the late 20th *** terrestrial grids have recorded an ITT of total precipitation in either the 1970s or 1980s,and 45.7% of the terrestrial grids in the study have seen a decreasing trend in total annual precipitation after the break- point,with the remaining 54.3% having experienced an increasing ***,global terrestrial regions have experienced either an increasingly warm and dry climate or an increasingly warm and wet *** analysis of ITT of regional mean SAT and total pre- cipitation in 22 regions shows that the Northern American continent has become increasingly warm and dry after the last interdecadal ***,the African continent has become increasingly warm and wet,with both Europe and most of Asia having the same *** South America and the West of Australia have experienced an opposite trend in climate,becoming increasingly cold and wet.

关键词： Global terrene Surface air temperature Precipitation Interdecadal trend turning

Research on applying physical chaos generator to spacecraft information security

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science china(Technological sciences) 2009年第5期52卷 1463-1470页

作者： ZHAO HePing state key laboratory of Information Security,Graduate University of chinese academy of sciences,beijing 100049,china china academy of Space Technology,beijing 100094,china state key laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China china academy of Space Technology Beijing China

The effectiveness of a short-length message extension method based on physical chaos generator was analyzed and the entropy of the extended message was calculated in this *** analysis demon-strated that with the mentioned method the entropy of short-length messages,which are repeatedly used in spacecraft data systems,is obviously increased,and the security of transmission is enhanced as *** paper also presented an improvement of the protocol for secret key agreement presented by *** and *** of depending on characteristics of communication channel,this method takes advantage of the random data produced by physical chaos generator to preset the initial parameters of the procedure on both sides of communication,so that the procedure and quantity of cipher key can be precisely *** method can be used to cipher key management of se-cure communication between long life-span spacecraft and ground system.

关键词： physical chaos generator spacecraft information security message extension cipher key management

The theoretical research of basic function method in incompressible viscous flow and its simulations in three-dimensional aneurysms

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science china(Physics,Mechanics & Astronomy) 2009年第6期52卷 909-918页

作者： SHEN Fang1 & WU WangYi2 1 state key laboratory for Space Weather, Center for Space science and Applied Research, chinese academy of sciences, beijing 100190, china 2 state key laboratory of Turbulence and Complex Systems & Department of Mechanics and Engineering science, Peking University, beijing 100871, china state key laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China state key laboratory of Turbulence and Complex Systems & Department of Mechanics and Engineering science Peking University Beijing China

Basic function method is developed to treat the incompressible viscous flow. Artificial compressibility coefficient, the technique of flux splitting method and the combination of central and upwind schemes are applied to construct the basic function scheme of trigonometric function type for solving three-dimensional incompressible Navier-Stokes equations numerically. To prove the method, flows in finite-length-pipe are calculated, the velocity and pressure distribution of which solved by our method quite coincide with the exact solutions of Poiseuille flow except in the areas of entrance and exit. After the method is proved elementary, the hemodynamics in two-and three-dimensional aneurysms is researched numerically by using the basic function method of trigonometric function type and unstructured grids generation technique. The distributions of velocity, pressure and shear force in steady flow of aneurysms are calculated, and the influence of the shape of the aneurysms on the hemodynamics is studied.

关键词： basic function unstructured grid aneurysm viscous incompressible flow artificial compressibility flux splitting

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(Graduate University of chinese academy of sciences,beijing 100049,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)

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

Interfacial behaviors of PMMA-PEO block copolymers at the air/water interface

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science china Chemistry 2005年第6期48卷 567-573页

作者： CHENG Caixia1, JIAO Tifeng2, TANG Rupei1, LIU Minghua2 & XI Fu1 1. state key laboratory of Polymer Physics and Chemistry, Joint laboratory of Polymer science and Materials, Institute of Chemistry, chinese academy of sciences, beijing 100080, china 2. CAS key laboratory of Colloid and Interface science, Institute of Chemistry, chinese academy of sciences, beijing 100080, china state key laboratory of Polymer Physics and Chemistry Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences Beijing China CAS key laboratory of Colloid and Interface science Institute of Chemistry Chinese Academy of Sciences Beijing China

Diblock copolymer of PMMA291-b-PEO114 and triblock copolymer of PMMA120-b- PEO227-b-PMMA120 were synthesized and their interfacial properties at the air-water interface were investigated, where both blocks of polyethylene oxide (PEO) and poly(methyl methacrylate) (PMMA) are surface active but the former is soluble in water while the latter is not. Both the block copolymers could form monolayers with two obvious transition regions. The first transition point is around 10 mN/m, which could be assigned to the pancake-brush change of the PEO chains. The other is around 18 mN/m, which could be ascribed to the condensed packing of PMMA. The surface morphological changes during the compression of the Langmuir monolayers are inves-tigated by using the AFM and SEM methods for the films deposited at different surface pressure or molecular areas. At a lower surface pressure, a typical morphology of PEO-con- taining lipopolymers is observed. Upon compression, sphere-dominant morphologies were observed. While the diblock copolymer is easy to folding, the triblock copolymer is in favor of formation of circular domains through vesiculation.

关键词： PMMA-PEO, block copolymers, monolayer, Langmuir-Blodgett films, AFM.

Biosystematic studies on Adenophora potaninii ***(Campanulaceae) V.A taxonomic treatment

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Journal of Systematics and Evolution 2010年第6期48卷 445-454页

作者： Song GE De-Yuan HONG(state key laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,beijing 100093,china) (state key laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

Adenophora is an extremely variable genus,and its taxonomy is very *** the genus,Adenophora potaninii complex,including ***,***,***,***,***,***,and *** ***,is a typical group with different taxonomical treatments due to high level of morphological *** carried out extensive biosystematic studies based on population sampling,transplantation experiments and offspring tests,cluster analysis,and a crossing *** results reveal four main findings.(i) Leaf forms of the *** complex were extremely polymorphic;the leaf form of *** and ***,and that of *** and *** could be found,respectively,on a single population or among the offsprings of a single plant.(ii) Cluster analysis and a crossing experiment indicated that *** and *** could not be separated from ***,nor *** from ***.(iii) Adenophora potaninii and *** were gradational in morphology and their compatibility value was slightly reduced compared to that within each entity.(iv) Adenophora lobophylla was distinct from the other members of the complex in shape and size of corolla,relative length of style,and shape of *** species was incompatible reproductively with the other members of the complex,but partly compatible with ***,a species in another ***,we recognized only one species with two subspecies in the complex,*** *** and ***,moved *** out of the complex,and reduced all the other names as new synonyms.

关键词： Adenophora potaninii biosystematics populations species complex taxonomy.

Polynomial analysis of canopy spectra and biochemical component content inversion

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science china Earth sciences 2005年第10期48卷 1780-1791页

作者： YAN Chunyan1, LIU Qiang1, NIU Zheng1, WANG Jihua2, HUANG Wenjiang2 & LIU Liangyun 2 1. state key laboratory of remote sensing science, Jointly Sponsored by the Institute of remote sensing Applications of chinese academy of sciences and beijing Normal University, beijing 100101, china 2. National Engineering Research Center for Information Technology in Agriculture, beijing 100089, china Jointly Sponsored by the Institute of remote sensing Applications of chinese academy of sciences and beijing Normal University National Engineering Research Center for Information Technology in Agriculture

A polynomial expression model was developed in this paper to describe directional canopy spectra, and the decomposition of the polynomial expression was used as a tool for re-trieving biochemical component content from canopy multi-angle spectra. First, the basic formula of the polynomial expression was introduced and the physical meaning of its terms and coeffi-cients was discussed. Based on this analysis, a complete polynomial expression model and its decomposition method were given. By decomposing the canopy spectra simulated with SAILH model, it shows that the polynomial expression can not only fit well the canopy spectra, but also show the contribution of every order scattering to the whole reflectance. Taking the first scattering coefficients a10 and a01 for example, the test results show that the polynomial coefficients reflect very well the hot spot phenomenon and the effects of viewing angles, LAI and leaf inclination angle on canopy spectra. By coupling the polynomial expression with leaf model PROSPECT, a canopy biochemical component content inversion model was given. In the simulated test, the canopy multi-angle spectra were simulated by two different models, SAILH and 4-SCALE re-spectively, then the biochemical component content was retrieved by inverting the coupled polynomial expression + PROSPECT model. Results of the simulated test are promising, and when applying the algorithm to measured corn canopy multi-angle spectra, we also get relatively accurate chlorophyll content. It shows that the polynomial analysis provides a new method to get biochemical component content independent of any specific canopy model.

关键词： polynomial expression, canopy spectra, decomposition, biochemical component content, inversion.