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Biomass estimation and uncertainty analysis based on CBERS-02.CCD camera data and field measurement

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Science china(Technological sciences) 2005年第S2期48卷 116-128页

作者： CHEN Liangfu1,2, GAO Yanhua1,3, CHENG Yu1,3, WEI Zheng1,3, XIAO Qing1,4, LIU Qinhuo1, YU Tao1, LIU Qijing5, GU Xingfa1 & TIAN Guoliang1 1. State Key Laboratory of Remote Sensing Science, institute of Remote Sensing Applications, chinese academy of sciences, beijing 100101, china 2. Geography and Environment College, Jiangxi Normal University, Nanchang 330027, china 3. Graduate University of chinese academy of sciences, beijing 100039, china 4. beijing research institute of Uranium Geology, beijing 100875, china 5. institute of Geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, china State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Geography and Environment College Jiangxi Normal University Nanchang 330027 China Graduate University Chinese Academy of Sciences Beijing 100039 China beijing research {2. of Uranium Geology Beijing 100875 China institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing 100101 China

The study site is located in Qianyanzhou experimental station and the surrounding area. Based on CBERS-02.satellite data and field measurement, we not only discussed the relationship between NDVI and biomass of two species of coniferous plantations, namely, Pinus massoniana Lamb and Pinus elliottii Engelm, but also introduced the biomass models based on NDVI. The comparison between measured biomass in Qianyanzhou and biomass derived from CBERS-02.CCD data showed that it is feasible to estimate biomass based on NDVI. But its limitations cannot be ignored. This kind of model depends on the dominant vegetation species. There are some effect factors in estimating biomass based on NDVI. This paper analyzes these factors based on fine-resolution CBERS-02.CCD data and some conclusions are drawn: In Qianyanzhou, the area with good vegetation coverage, the nonlinearity of NDVI has little influence on scaling-up of NDVI. As a result of surface heterogeneity, scaling-up can cause NDVI within each pixel to change. Because scaling-up can cause pixel attribute to change, the applicability of biomass model is one of the sources of error in estimating biomass.

关键词： NDVI biomass scaling effect scaling-up.

Relationship between erosion and sediment yield in drainage basins of loess gully-hilly areas

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Journal of geographical sciences 2001年第1期11卷 71-79页

作者： CHEN Hao (institute of Geographic sciences and {2. resources research, CAS, beijing 100101, china) institute of Geographic sciences and {2. resources research CAS Beijing China

From a long-term point of view, the balance between erosion and sediment yield in a drainage system can basically realize, i.e., the delivery ratio can be close to 1. However, substantial variations among individual rainfall events or between annual delivery ratio exist, causing frequent sediment retaining or re-erosion and re-delivery of the retained sediments in a short period of time. Thus the delivery ratio will be 1. The sediment delivery ratio is closely related to the spatial distribution of rainfall and magnitude of rise and fall of peak flood and that of runoff depth in the drainage system. Delivery ratio of single event in a drainage system and changes of delivery capacity of silt-laden runoff in various classes of gullies can be expressed by transformation mechanism of shear force of a single rainstorm event with flood resulting from increase and decrease of peak flood per unit area.

关键词： delivery ratio interaction flood and geomorphology dynamic mechanism rainstorm flood

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, {2. 100081, china institute of Geographic sciences and natural resources research, chinese academy of sciences,{12., china Mathematics Department, Ocean University of china, Qingdao 2.6071, china Shanghai institute of Plant Physiology and Ecology, chinese academy of sciences, Shanghai 2.0032. china) chinese academy of Meteorological Science Beijing 100081 China institute of Geographic sciences and {2. 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, 2. m a.s.l., in the North china Plain) and at Lhasa (2.°41'N, 91°2.'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.

Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1 & GOU Chenhua1,2.1. institute of Engineering Thermophysics, chinese {2. of sciences, beijing 100080, china 2. Graduate School, chinese {2. of sciences, beijing 100080, china institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

Characteristics and geological significance of olivine xenocrysts in Cenozoic volcanic rocks from western Qinling

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Progress in natural Science:Materials International 2006年第12期16卷 1300-1306页

作者： SU Benxun~ 1,2.**, ZHANG Hongfu~1, XIAO Yan~ 1,2.and ZHAO Xinmiao~ 1,2.(1. State Key Laboratory of Lithospheric Evolution, institute of Geology and Geophysics, chinese {2. of sciences, beijing 10002., china 2. Graduate School of chinese {2. of sciences, beijing 100039, china) State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Graduate School of chinese academy of {2. Beijing 100039 China

Cenozoic volcanic rocks from the Haoti, Dangchang County of the western Qinling Mountains, contain a few clearly-zoned olivines. These olivines are relatively big in grain sizes and usually have cracks or broken features. Their cores have similar compositions （Mg#=90.4-91.0） to those for the peridotitic xenoliths entrained in host volcanic rocks and their rims are close to the compositions of olivine phenocrysts （Mg#=85.5-81.9）. The CaO contents in these zoned olivines are lower than 0.1%. These features demonstrate that the clearly-zoned olivines are xenocrysts and disaggregated from mantle peridotites. The zoned texture was the result of the interaction between the olivine and host magma. Available data show that the volcanic rocks would have been derived from the mantle source metasomatized by subducted hydrathermally-altered oceanic crust. The formation of these Cenozoic volcanic rocks was perhaps related to the rapid uplift of the Tibetan Plateau.

关键词： Western Qinling Dangchang Haoti Cenozoic volcanic rocks olivine xenocrysts zoned texture.

The Application of Multiple Evaluating Methods on the Comprehensive Evaluation of Urban-rural Interaction and Conjunctional Development of china

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chinese Journal of Population,resources and Environment 2005年第2期3卷 35-41页

作者： Duan Juan 1,2. Lu Qi 1 & Wen Yuyuan 31 institute of Geographic sciences and {2. resources research, chinese academy of sciences,beijing 100101, china2.Graduate School of chinese academy of sciences, beijing 100039,china3 institute of Regional Economics and Urban Management sciences, Renmin Univercity of china,beijing 100872. china institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing 100101 China Graduate School of chinese academy of {2. Beijing 100039 China institute of Regional Economics and Urban Management sciences Beijing 100872 China

Urban-rural interaction and conjunctionaldevelopment is the effective way of harmonizingurban-rural relationship and promoting urban-ruraldevelopment. However, there are differences in thelevel of urban-rural interaction and conjunctionaldevelopment of china. How to measure and reflectthe difference properly is a decision-makingfoundation for optimizing urban-rural developmentof different regions. The paper employs multiplemethods to evaluate and order the urban-ruralinteraction and conjunctional development of 31provinces (municipalities) in china. Kendall’s Wconsistency coefficient is employed to give a consistenttest for the evaluation result series, and the resultsof multiple methods are aggregated as the finalevaluation value. The results reflect the level ofregional urban-rural interaction and conjunctionaldevelopment in china.

关键词： Urban-rural interaction urban-ruralconjunctional development comprehensive evaluation consistency test.

Channel characteristics and formation mechanism of Ganjiang River

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Journal of geographical sciences 2000年第4期10卷 129-134页

作者： CHEN Zhi-qing (institute of Geographic sciences and {2. resources research, chinese academy of sciences, beijing 100101, china) 中科院地理科学与资源所北京

Relative straight channel of the middle and upper reaches of Ganjiang has been formed due to thecontraction of mountains and hills being composed of bedrocks on both banks of the river. But however, At the lower reaches, branching channel predominates due to limited contracting force of the river banks as the evolution and development of branching channels are closely related with locations and controle effect of nodal points. There are sufficient water containing less sediments in Ganjiang River where the sharp rise and fall of the flow discharge makes the grain size of the particles rather coars. Gravels mingled with sand dominate the channel bed and components of central bars are also much coarser than those in sandy bed of the middle and lower reaches of the Yangtze River.

关键词： channel characteristics genetic mechanism comparison with middle and lower Yangtze Ganjiang River

Regional container transportation system for Northeast Asia economic cooperation in the 2.^(st) century

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Journal of geographical sciences 2000年第4期10卷 59-66页

作者： JIN Feng-jun (institute of Geographic sciences and {2. resources research, chinese academy of sciences, beijing 100101, china) 中科院地理科学与资源所北京

In this paper, the roles of infrastructure development and transportation coordination for Northeast Asian economic cooperation are discussed. It would be necessary to establish an efficient transportation network as soon as possible. 'Hub-and-Spoke'transportation system and china-Korean peninsula railway container transportation system might be more significant for regional economic cooperation.

关键词： infrastructure economic cooperation transportation organization Hub-and-Spoke system high-speed transport

Improvement of Ecological Footprint Method and Application in Henan Province

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chinese Journal of Population,resources and Environment 2005年第1期3卷 44-48页

作者： Niu Shuhai, Jin Fengjun & Liu Yi institute of geographical {2. and natural resources research, CAS, beijing 100101, china institute of geographical {2. and natural resources research CAS Beijing 100101 China

The measure of sustainable development has always been an important and difficulty subject, and the major evaluation model has three types: indicators based on system theory and methods, indicators relied on economic valuation of the environment, sustainability indicators including biophysical assessments. The ecological footprint analysis initiated by William E. Rees, one of the indicators including biophysical assessments, gets rid of the defects of the other models. Ecological footprint has gradually become popular on account of the measuring indexes based on scientific theory, innovative thought-way and its wide adaptability. This paper introduces the conception and computation method, making a progress and making up for the method of ecological footprint, and finally, makes an application analyses through Henan province regional sustainable development.

关键词： sustainable development ecological footprint input/occupancy-output model integrated development degree