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research on Jiuquan-Jiayuguan-Yumen Region's Dynamic Changing of Urbanization Based on Self-Organizing Model

chinese Journal of Population,resources and Environment 2005年第3期3卷 22-28页

作者： Li Ming 1,2 & Fang Chuanglin 2 1 Graduate School of the chinese academy of sciences, beijing 100039,china 2 institute of geographical sciences and natural resources research, CAS, beijing 100101, china Graduate School of the chinese academy of sciences Beijing 100039 China institute of geographical sciences and natural resources research CAS Beijing 100101 China

Based on the self-organizing modeling principle in the dissipative structure theory, the paper regards the migration coupling between the regions as the influence factor to create the model of regional urbanization simulation and prediction, which is more practical to simulate the space-time and dynamic evolvement characteristics of regional urbanization level. According to the historical data about the population and urbanization of Jiuquan, Jiayuguan andYumen cities, the past 50 years' dynamic evolvement trend is simulated and the following 50 years' dynamic evolvement trend is predicted with the urbanization dynamic evolvement model based on the self-organizing model. The analysis of effective factors such as economic increase, resources exploitation, ecosystem construction, traffic location, national policies, population migration are given, then the reasons of the dynamic evolvement differences of the three cities' urbanization are drawn. The study suggests that the self-organizing model is fit for the simulation of Jiuquan-Jiayuguan-Yumen regional urbanization level in the past 50 years, and the departure between the stimulant and the actual data is under 5%, so it can be used to predict the urbanization future of the three cities. The predicted results show that the regional population will reach 1.074 million and the regional urbanization level will be 72.56%.

关键词： self-organizing urbanization dynamic evolvement Jiuquan-Jiayuguan-Yumen region

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china's Regional Policies:Progress of the 11^(th) Five Year Plan Period and Prospect of the 12^(th) Five Year Plan Period

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chinese Journal of Population,resources and Environment 2011年第2期9卷 90-96页

作者： Chen Xuebin1,2 1.institute of geographic sciences and natural resources research,chinese academy of sciences,beijing 100101,china 2.National Development and Reform Commission,beijing 100824,china institute of geographic sciences and natural resources research Chinese Academy of Sciences Beijing 100101 China National Development and Reform Commission Beijing 100824 China

During the 11th Five Year Plan period,china improved its policy system for the overall strategy of regional development,and established and completed the policies intended for the promotion of regional cooperation and ***,regional development in china took on a series of positive changes such as the enhancement of *** the 12th Five Year Plan period,china will fully implement and continuously improve the policy measures for development in its four major regions,strengthen differentiated guidance to different regions in line with the planning for major function-oriented zones,and accelerate the establishment of basic systems that facilitate coordinated regional development.

关键词： regional policy progress prospect

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Origin Distribution Patterns and Floating Population Modeling:Yiwu City as a Destination

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chinese geographical Science 2012年第3期22卷 367-380页

作者： LI Hongsheng WANG Yingjie HAN Jiafu State Key Laboratoty of resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Existing quantitative migration studies are mainly at the inter-region or inter-province level for lacking of detailed geo-referenced migration ***,few of them integrate explorative spatial data analysis and spatial regression model into migration *** on aggregated registered floating population data from 2005 to 2008,the phenomena that population floating to Yiwu City in Zhejiang Province is analyzed at the provincial and county *** spatial layout of Yiwu's pull forces is proved as a V-shaped pattern excluding Sichuan Province based on map visualization *** the migration ratio in 2007 as an explanatory variable,two models are compared using ordinary least square,spatial error model and spatial lag model methods for county-level data in Jiangxi and Anhui *** model with migration stock provides an improved fitting over the model without migration stock according to the model fitting *** floating population flocking into Yiwu City from Jiangxi is determined mostly by migration stock while the determinant factors are migration stock and distance to Yiwu City for *** distance-decay effect is true for migration flow from Anhui to Yiwu City while the distance rule is not confirmed in Jiangxi with the best fitting *** correlation between per capita net income of rural labor forces and migration ratio is not significant in Jiangxi and significant but at the 0.1 level only in *** analysis shows that the distance,income and man-land ratio are important factors to explain population floating at earlier ***,as the dynamic population floating process evolves,the determinant factor would be migration stock.

关键词： floating population origin distribution visualization spatial regression model Yiwu City GIS

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Effective solutions to a global 3D visual system in networking environments

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Science china Earth sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2, ZHANG Yan3, YANG Chongjun2, LIU Suhong1, REN Yingchao2, RUI Xiaoping2 & LIU Donglin2 1. State Key Laboratory of Remote Sensing sciences, School of Geography and Remote Sensing, beijing Normal University, beijing 100875, china 2. State Key Laboratory of Remote Sensing sciences, institute of Remote Sensing Applications, chinese academy of sciences, beijing 101001, china 3. institute of geographical sciences and natural resources research, chinese academy of sciences, beijing 101001, china State Key Laboratory of Remote Sensing sciences School of Geography and Remote Sensing Beijing Normal University Beijing China chinese academy of sciences State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications China institute of geographical sciences and natural resources research Chinese Academy of Sciences China

The development of Web-based global 3D visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

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Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai

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Science china Earth sciences 2005年第7期48卷 939-949页

作者： SHAO Xuemei1, HUANG Lei1, LIU Hongbin2, LIANG Eryuan1, FANG Xiuqi3 & WANG Lili1 1. institute of geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, china 2. National Climate Center, beijing 100081, china 3. beijing Normal University, beijing 100875, china institute of geographic sciences Natural Resources Research Chinese Academy of Sciences Beijing 100101 China National Climate Center Beijing 100081 China beijing Normal University Beijing 100875 China

Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD1520—1633 and 1933—2001, whereas dry intervals in 1429—1519 and 1634—1741. In ad- dition, the magnitude in precipitation variation was lower before 1430 with about 15 mm, but it increased to 30 mm during the period of 1430 to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 21st century.

关键词： northeastern part of the Qaidam Basin tree-ring width series of Qilian juniper precipitation reconstruction in 1000 years.

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Value of ecosystem services in china

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chinese Science Bulletin 2000年第10期45卷 870-876页

作者： CHEN Zhongxin & ZHANG XinshiLaboratory of Quantitative Vegetation Ecology, institute of Botany, chinese academy of sciences, beijing 100093, china Current address: institute of natural resources and Regional Planning, chinese academy of Agricultural sciences, beijing 100081, china Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing China

The function and services are the important components of the life-support system in theplanet, as well as the basic elements for sustainable development of environment and society. It is a must to evaluate it for incorporating it with the social-economic system. It is also an important approach to draw the public attention on the environmental and ecosystem conservation. In this study, the ecosystem function and services in china were estimated by employing the classification and economic parameters from Costanza et al. The type and area of terrestrial ecosystems were extracted from Vegetation Map of china (1:4 000 000), and then the distribution map of ecosystem services of china was drawn. According to our calculation, the total value of ecosystem services in china is 77 834.48×108 RMB yuan per annum. The value for terrestrial ecosystem is 56 098.46×108 yuan per annum, and that for marine ecosystem is 21 736.02×108 yuan per annum. The value of ecosystem services in china is 1.73 times bigger

关键词： ecosystem function service.

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A NEW STABILIZED FINITE ELEMENT METHOD FOR SOLVING THE ADVECTION-DIFFUSION EQUATIONS

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Journal of Computational Mathematics 2002年第1期20卷 57-64页

作者： Huo-yuan Duan (institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china) institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 北京 100080

Focuses on a study on the development of a stabilized finite element method for solving the advection-diffusion equations with a zero Dirichlet boundary condition. Problem formulation; Error analysis.

关键词： advection-diffusion equation stabilized finite element method

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Spatial and temporal variation of soil moisture near the interface of high/low stands

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Journal of geographical sciences 2000年第4期10卷 109-120页

作者： Liu Su-xia, Mo Xing-guo (institute of geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, P. R. china) 中科院地理科学与资源所北京

In order to explore the spatial variability of soil moisture near the interface of high/low stands, an experiment was conducted at Luancheng Experimental Station, chinese academy of sciences, Hebei, china from May to June, 1996. By analyzing the observed soil moisture data, it shows that there exists an obvious turning point of soil moisture pattern from one side of the interface to another. The effect of drier soil closer to the interface in winter wheat field is obvious, which is mainly due to the better ventilation condition near the interface in winter wheat filed than in alfalfa field. The irrigation in large scale is one of the most important factors to control the spatial pattern of soil moisture while the small scale human disturbing activity, such as the stealing event occurred during our observation, does not change the spatial pattern of soil moisture obviously. Latent heat, calculated by Bowen ratio method based on our observed micrometeorological data, is shown larger in alfalfa than that in winter wheat both at earring stage from May 8 to 10 and mature stage from June 11 to 14. This fact, together with the larger ground temperature and a little bit larger wind velocity in lower layer, explains that the soil is drier in alfalfa than in winter wheat from May 8 to 10. While for the period from June 11 to 14, irrigation's effect changes the natural interrelationship of soil moisture with meteorology and ground temperature.

关键词： soil moisture interface of alfalfa/winter wheat field

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FARMLAND AND URBAN AREA DYNAMICS MONITORING INchina USING REMOTE SENSING AND SPATIALSTATISTICS METHODOLOGY

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chinese geographical Science 2001年第1期11卷 42-49页

作者： LIU Ming-liang, ZHUANG Da-fang, LIU Ji-yuan (institute of Remote Sensing Applications, the chinese academy of sciences, beijing 100101, P. R. china institute of geographical sciences and natural resources research, the chinese academy of sciences, Beij institute of Remote Sensing Applications the Chinese Academy of Sciences Beijing P. R. China institute of geographical sciences and natural resources research the Chinese Academy of Sciences Beijing P. R. China

With the need in the global change research project for the land -use/land-cover change information, most international and regional research organization or groups have put amounts of efforts to improve of the dynamics monitoring and database updating techniques. With the pressure on nature environment from increasing population and decreasing farmland be- coming significant more and more in china, the farmland urban dynamics in historical and current times, even the change trends in the future, should be monitored and analyzed serving for regional and national social, economic and environmental sustain- able development in the long future. Based on spatial and temporal series of land -use/land-cover database resources, chinese academy of sciences designed a sampling framework for monitoring farmland and urban area dynamics in regional and national level. In order to test the accuracy of the sampling schema for national and regional level, we took two provinces area into overall covered change detecting process with TM images data through being inter’Preted by digitalization on the screen. The result shows that our stratified random sampling schema is suitable for monitoring land -use/land-cover change at national and regional level with quick response, high accuracy and low expenses. The land-use/land-cover change (LUCC) information can update the LUTEA database for global change research during certain period so that the forecasting process and evaluating analysis on land resources and environment under human and natural driving force will get essential data and produce valuable conclusions.

关键词： Land-use/Land-cover change spatial sampling scheme remote sensing

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Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, china

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Science china Earth sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2 1. institute of geographical sciences and natural resources research, chinese academy of sciences, beijing 100101, china 2. Laboratory for Earth Surface Processes, Peking University, beijing 100871, china institute of geographical sciences and natural resources research Chinese Academy of Sciences Beijing China Laboratory for Earth Surface Processes Peking University Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952―2003 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952―1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92% of total transfer fluxes of HCHs isomers. There were approximately 253t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983, and this percentage may descend to 0.5% after 20 years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

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