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Relationship between Surface Pollen and Modern Vegetation in Southwestern china

Journal of Mountain Science 2010年第2期7卷 176-186页

作者： PAN Tao DAI Erfu and WU Shaohong institute of Geographic Sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 China Graduate University of chinese academy of Sciences BeO'ing 100049 China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China

Based on the pollen data obtained from thirty-five surface soil samples and investigated vegetation data from seven plant quadrats,the quantitative relationship between surface soil pollen and modern vegetation are studied in the longitudinal range-gorge region (LRGR) in Southwestern china.R-values (referring to pollen assemblages) are calculated with pollen percentage and plant *** coefficients of similarity between pollen and vegetation are *** results show that the pollen assemblages on surface soil of all vegetation zones can basically represent the native vegetation,but the pollen assemblages are not fully according with the *** is due to the influencing factors including pollen preservation ability,pollen production,amount of exotic pollen and pollen *** pollen representation in surface soil is different in families and *** pollen of woody plants such as Pinus,Tsuga,Alnus,Fagus and Castanopsis are over-representative,but those of Quercus,Carpinus Myrica,Elaeocarpaceae,Ericaceae,Theaceae and Llex are underrepresentative;the pollen of herbaceous plants such as Artemisia and Rubiaceae are over-representative,while those of others including Gramineae and Araliaceae are *** R-values of the same taxon pollen in different vegetation zones are different,depending on their distances from the pollen *** coefficients of the similarity between plant communities and pollen assemblages are mostly over 70%,which indicate again that the surface soil pollen and spores assemblages can represent the *** is concluded that there is a good corresponding relationship between surface pollen assemblages and native vegetation in LRGR,and it is of great significance for reconstructing the past vegetation and paleoclimate using quantitative fossil pollen data in this region.

关键词： Longitudinal range-gorge region (LRGR) Pollen assemblage Vegetation R-value Coefficient of similarity

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Monitoring of rice crop using ENVISAT ASAR data

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Science china Earth Sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2, SUN Guoqing1,3 & PANG Yong4 1. State Key Laboratory of Remote Sensing Science, institute of Remote Sensing Applications, chinese academy of Sciences, beijing 100101, china 2. Graduate University of chinese academy of Sciences, beijing 100039, china 3. Department of Geography, University of Maryland, College Park, MD 20742, USA 4. forest Remote Sensing Lab, research institute of forest Resource and information Technology, chinese academy of For-estry, beijing 100091, china State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China Graduate University of chinese academy of Sciences Beijing China Department of Geography University of Maryland College Park USA forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

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The roles of a decision support system in applying forest ecosystem management in Northeast china

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Science china(Technological Sciences) 2006年第z1期49卷 9-18页

作者： DAI Limin, ZHENG Bofu, Guofan Shao & ZHOU Li State Key Lab of Systems Ecology, research Center for Eco-Environmental Sciences, chinese academy of Sciences, beijing 100085, china institute of Applied Ecology, chinese academy of Sciences, Shenyang 110016, china Department of forestry and Natural resources, Purdue University, West Lafayette, IN 47907, USA Graduate University of chinese academy of Sciences, beijing 100101, china State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences institute of Applied Ecology Chinese Academy of Sciences Department of forestry and Natural resources Purdue University

forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in china is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, forestAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of forestAR.

关键词： forest functions, forested landscapes, forest services, forest models, geographic information systems.

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Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The research Center of Mineral resources Exploration , chinese academy of Sciences , beijing 100101, china 2. institute of Geology , chinese academy of Sciences , beijing 100029, china 3. institute of High Energy Physics , chinese academy of Sciences , beijing 100817 , china 4. beijing University of Science and Engineering , beijing 100083, china Corresponding author The research Center of Mineral resources Exploration Chinese Academy of Sciences Beijing China institute of Geology Chinese Academy of Sciences Beijing China institute of High Energy Physics Chinese Academy of Sciences Beijing China beijing University of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

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Reconstructing mean maximum temperature of growing season from the maximum density of the Schrenk Spruce in Yili,Xinjiang,china

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chinese Science Bulletin 2009年第13期54卷 2300-2308页

作者： CHEN Jin1,2,3,WANG LiLi1,4,5,ZHU HaiFeng1 & WU Pu1 1 institute of Geographic Sciences and Natural resources research,chinese academy of Sciences,beijing 100101,china 2 Graduate University of chinese academy of Sciences,beijing 100049,china 3 institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of Sciences,beijing 100044,china 4 institute of Tibetan Plateau research,chinese academy of Sciences,beijing 100085,china 5 institute of Desert and Meteorology,china Meteorological Administration,ürümqi 830002,china institute of Geographic Sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 China Graduate University of chinese academy of Sciences Beijing 100049 China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China institute of Desert and Meteorology China Meteorological Administration Ürümqi 830002 China

To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TRW) were established with the Schrenk Spruce(Picea schrenkiana *** Mey) collected from six sites to analyze the characteristics and ability of response to climate *** results suggest that the MXD chronology of the Schrenk Spruce from different sampling sites responded to climate change well and were positively correlated with the mean maximum temperature and the mean temperature from April to August in the study *** mean maximum temperature anomaly from April to August,spanning the years from 1848 to 2000,was reconstructed by three MXD chronologies which were selected by stepwise *** reconstructed function was stable and explained 56.2% of the *** reconstructed results indicated a cold span of 153 years in spring and summer from the beginning of the 1950s to the beginning of the 1970s in the Yili *** strongly increasing tendency was detected in the mean maximum temperature anomaly from April to August during this reconstructed period.

关键词：平均最高气温伊犁谷地最大密度云杉胡杨生长季节新疆树木年轮宽度

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Formal analysis and design of multi-party fair exchange protocols

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Science in china(Series F) 2006年第2期49卷 155-174页

作者： QING Sihan1,2,3 & LI Gaicheng1,3 1. Engineering research Center for information Security Technology, institute of Software, chinese academy of Sciences, beijing 100080, china 2. beijing Zhongke Ansheng Corporation of information Technology, beijing 100080, china 3. Graduate School of the chinese academy of Sciences, beijing 100039, china Engineering research Center for information Security Technology Institute of Software Chinese Academy of Sciences beijing Zhongke Ansheng Corporation of information Technology Graduate School of the chinese academy of Sciences

Based on the origin of message items and channel combination between transacting parties, and events and relations among events, this paper presents a concise, precise, and hierarchical model for general fair exchange protocols, formally specifies various security requirements which are able to reflect inherent requirements for fair exchange protocols more rigorously, and partition these security requirements with fine granularity. This work helps analyze, debug, and design multi-party fair exchange protocols more effectively and elaborately,

关键词： fair exchange logical protocol formal model security requirement.

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GIS-based analysis of forest degradations in Baihe forestry Bureau,northeast china

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Science china(Technological Sciences) 2006年第z1期49卷 167-176页

作者： ZHOU Li, DAI Limin , Guofan Shao, XU Dong, WANG Hui & BAI Jianwei institute of Applied Ecology, chinese academy of Sciences, Shenyang 110016, china Graduate University of chinese academy of Sciences, beijing 100101, china Department of forestry and Natural resources, Purdue University, West Lafayette, IN 47907, USA Department of City Development, Jinan University, Jinan 250002, china academy of forest Inventory and Planning, State forestry Administration, beijing 100714, china institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China

forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast china. In order to strengthen forest resource management, this paper analyzed management-induced changes in forest structure, tree species composition and forest landscape pattern from 1987 to 2000 for Baihe forestry Bureau in Jilin Province based on digitized forest parcel maps and forest survey data. The results suggested that the area of Mature, High-Stocking, and Close-Canopy forests decreased by 31.4%, 55.9% and 10.7% respectively; volume of Mixed forest, the native forest vegetation type, decreased by 17.8%;the number of patches increased tremendously but the mean patch density decreased sharply for Mature, High-Stocking, Close-Canopy, and Mixed forests. All the changes in forest structure, species composition, and landscape pattern indicated severe degradations going on with the forests in Baihe forestry Bureau. Because of the effect of degradation to forest services, restoring forest resources and protecting biodiversity has become urgently important. The strategies of sustainable forest management need to be worked out and implemented.

关键词： geographic information system, forest management, Changbai Mountains, forest change, forest decline.

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Oxygen and hydrogen isotopic compositions of coexistent minerals of the Tasigake alkali granite pluton,northern Xinjiang:constraints upon the cause of ^(18)O-D depletion and the ^(18)O/^(16)O exchange kinetics

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chinese Science Bulletin 1999年第12期44卷 1086-1093页

作者： LIU Wei, ZHAO Zhenhua ZHANG Fuqin research Center of Mineral resources Exploration, institute of Geophysics , chinese academy of Sciences , beijing 100101, china Guangzhou institute of Geochemistry, chinese academy of Sciences , Guangzhou 510640, china research Center of Mineral Resource Exploration Institute of Geophysics Chinese Academy of Science Beijing China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Oxygen and hydrogen isotopic compositions have been determined of three coexistent mineral triplets of alkali feldspar, quartz, arfvedsonite of 11 samples collected from the Tasigake alkali granite pluton, Ulungur River region, northern Xinjiang. Isotopic exchange with meteoric water during subsolidus cooling caused strong 18O-D depletion and the remarkable nonequilibrium 18O/16O relation between coexistent minerals. 18O/16O exchange kinetic effects of the three minerals are simultaneously and consistently modelled. Exsolution and microtextural reorganization of alkali feldspar, and infiltration of water have been mutually facilitated by each other. Shallow intrusion, and circulation of meteoric water throughout the pluton cool it effectively. As a result, the "heat engine" is rapidly extinguished, and the nonequilibrium 18O/16O relation is frosen.

关键词： 18O-D depletion isotopic exchange kinetics alkali granite Ulungur.

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Revision of seismic design codes corresponding to building damagesin the “5.12” Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 147-155页

作者： Wang Yayong institute of Earthquake Engineering, china academy of Building research, beijing 100013, china institute of Earthquake Engineering China Academy of Building Research Beijing 100013 China

A large number of buildings were seriously damaged or collapsed in the "5.12" Wenchuan earthquake. Based on field surveys and studies of damage to different types of buildings, seismic design codes have been updated. This paper briefly summarizes some of the major revisions that have been incorporated into the "Standard for classification of seismic protection of building constructions GB50223-2008" and "Code for Seismic Design of Buildings GB50011-2001." The definition of seismic fortification class for buildings has been revisited, and as a result, the seismic classifications for schools, hospitals and other buildings that hold large populations such as evacuation shelters and information centers have been upgraded in the GB50223-2008 Code. The main aspects of the revised GB50011-2001 code include: (a) modification of the seismic intensity specified for the Provinces of Sichuan, Shanxi and Gansu; (b) basic conceptual design for retaining walls and building foundations in mountainous areas; (c) regularity of building configuration; (d) integration of masonry structures and precast RC floors; (e) requirements for calculating and detailing stair shafts; and (f) limiting the use of single-bay RC frame structures. Some significant examples of damage in the epicenter areas are provided as a reference in the discussion on the consequences of collapse, the importance of duplicate structural systems, and the integration of RC and masonry structures.

关键词： Wenchuan earthquake earthquake damage to buildings revision of seismic design codes

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Comparative analysis of temperature and CO2 fluxes for winter wheat in Tibetan Plain and North china Plain using the EMD method

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Progress in Natural Science:Materials International 2006年第10期16卷 1066-1071页

作者： JIANG Zhaoyang, YU Qiang, LEI Shuhe, WANG Tianduo, SUN Xiaomin and ZHANG Renhua ( chinese academy of Meteorological Science, beijing 100081, china institute of Geographic Sciences and Natural resources research, chinese academy of Sciences, beijing 100101, china Mathematics Department, Ocean University of china, Qingdao 266071, china Shanghai institute of Plant Physiology and Ecology, chinese academy of Sciences, Shanghai 200032, china) chinese academy of Meteorological Science Beijing 100081 China institute of Geographic Sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 China Mathematics Department Ocean University of China Qingdao 266071 China Shanghai institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai 200032 China

Comparative study of spectral properties of temperature and CO2 fluxes measured by eddy covariance method at Yucheng (36°57'N, 116°36'E, 28 m a.s.l., in the North china Plain) and at Lhasa (29°41'N, 91°20'E, 3688 m a.s. 1., on the Tibetan Plateau) is described using the empirical mode decomposition (EMD) method. The main results are: (1) The intrinsic oscillation modes or intrinsic mode functions (IMFs) were extracted from data of temperature ( T) and CO2 fluxes (F) measured at Yucheng ( T1 and F1) and Lhasa ( T2 and F2) . (2) Hilbert transform was applied to these IMF components, then the Hubert-Huang spectra and the marginal spectra of these data were obtained. (3) Comparison of temperature and CO2 fluxes in North china Plain and on Tibetan Plain illustrated that the characteristic frequencies corresponding to T1, F1, T2 and F2 are 0.05 Hz, 0.03 Hz, 0.014 Hz and 0.005 Hz, respectively.

关键词： empirical mode decomposition (EMD) intrinsic mode function (IMF) flux Hilbert transform wheat Tibet.

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