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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,{2. 2.institute of geographical sciences and natural resources research, CAS, beijing 1.01.1. china Graduate School of the chinese academy of sciences Beijing 100039 China institute of geographical {2. 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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Rocky Land Desertification and its Driving Forces in the Karst Areas of Rural Guangxi,Southwest china

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Journal of Mountain Science 2008年第4期5卷 350-357页

作者： LIU Yansui WANG Jieyong DENG Xiangzheng institute of Geographic sciences and {2. resources research Chinese Academy of Science Beijing 100101 China institute of Geographic sciences and {2. resources research Chinese Academy of Science Beijing loolo~ ChinaGraduate University of Chinese Academy of Sciences Beijing 100039 China

With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst *** desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natural settings and human activities,because of which its eco-environment has been deteriorated in recent years,and farmland has been disappearing sharply at the same ***,in turn,has exacerbated the poverty level in the rural areas of the *** this study,we monitored the spatial distribution of rocky land desertification and its temporal evolution using Landsat TM/ETM images of 1985,1995,2.00 and *** also analyzed the driving forces of the desertification and its *** constructing regression models by using all the relevant variables and considering the lagged effects as well as fixed effects,we quantified the exact role of different factors causing rocky land desertification in the study area with some new *** new findings in this study are greatly helpful for preserving,restoring and reconstructing the degraded mountain environment in Guangxi and other karst areas in Southwest china,and also for alleviating poverty in the rural areas in the future.

关键词： Rocky land desertification karstmountain area rural poverty driving force Guangxi Southwest china

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Floating Population Increase and Its Influence on the Urban Population Situation:A Case Study in beijing

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chinese Journal of Population,resources and Environment 2005年第1期3卷 27-35页

作者： Wu Peilin 1,2.& Lu Qi 2.1. Shandong University of Technology, Zibo Shandong 2.5049, china 2. institute of geographical sciences and natural resources research,{2., beijing 1.01.1. china Shandong University of Technology Zibo Shandong 255049 China institute of geographical {2. and natural resources research Chinese Academy of Sciences Beijing 100101 China

Floating population is a special population group in china resulting from the implementation of household registration system. This paper uses a set of floating population survey data, population censuses data and statistical data to analyze the increase and influence of floating population on the urban population situations in beijing. It is found that beijing has experienced a rapid increase of floating population since the 1990s and that the increase of this group has become the key factor of the current population expansion in the city. Its distribution in the urban regions intensified and extended the suburbanization process of the capital. In addition, the population structures of sex, age, education and employment in beijing have changed to some extent due to the influx of floating population.

关键词： Floating population Household registration system (Hukou) Population expansion Suburbanization Population structure beijing

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A comparison between simulated and measured CO_2.and water flux in a subtropical coniferous forest

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Science china Earth sciences 2006年第S2期49卷 241-251页

作者： GU Fengxue, CAO Mingkui, WEN Xuefa, LIU Yunfen & TAO Bo institute of Geographic sciences and {2. resources research, chinese academy of sciences, beijing 1.01.1. china Graduate University of the chinese academy of sciences, beijing 100049, china institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing China Graduate University of the chinese academy of sciences Beijing China

Using data from eddy covariance measurements in a subtropical coniferous forest, a test and evaluation have been made for the model of Carbon Exchange in the Vegetation-Soil-Atmosphere (CEVSA) that simulates energy transfers and water, carbon and nitrogen cycles based on ecophysiological processes. In the present study, improvement was made in the model in calculating LAI, carbon allocation among plant organs, litter fall, decomposition and evapotranspiration. The simulated seasonal variations in carbon and water vapor flux were consistent with the measurements. The model explained 90% and 86% of the measured variations in evapotranspiration and soil water content. However, the modeled evapotranspiration and soil water content were lower than the measured systematically, because the model assumed that water was lost as runoff if it was beyond the soil saturation water content, but the soil at the flux site with abundant rainfall is often above water saturated. The improved model reproduced 79% and 88% of the measured variations in gross primary production (GPP) and ecosystem respiration (Re), but only 31% of the variations in measured net ecosystem exchange (NEP) despite the fact that the modeled annual NEP was close to the observation. The modeled NEP was generally lower in winter and higher in summer than the observations. The simulated responses of photosynthesis and respiration to water vapor deficit at high temperatures were different from measurements. The results suggested that the improved model underestimated ecosystem photosynthesis and respiration in extremely condition. The present study shows that CEVSA can simulate the seasonal pattern and magnitude of CO2.and water vapor fluxes, but further improvement in simulating photosynthesis and respiration at extreme temperatures and water deficit is required.

关键词： ecosystem CO2 and water flux CEVSA eddy covariance subtropical coniferous forest.

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Aridity/humidity status of land surface in china during the last three decades

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Science china Earth sciences 2005年第9期48卷 1510-1518页

作者： WU Shaohong1, YIN Yunhe1,2. ZHENG Du1 & YANG Qinye1 1. institute of geographical {2. and natural resources research, chinese academy of sciences (CAS), beijing 1.01.1. china 2. Graduate School of the CAS, beijing 100039, china institute of geographical {2. and natural resources research Chinese Academy of Sciences (CAS) Beijing China Graduate School of the CAS Beijing China

To clarify aridity/humidity status of land surface is helpful for studying environmental background and regional differences, seeking causes of environmental change, and providing a scientific basis for researches on climate change in the future. In this paper, the authors calcu- lated potential evapotranspiration of china using data from 616 meteorological stations during the period of 1971―2.00 with the Penman-Monteith model recommanded by FAO in 1998. Vy- sothkii’s model was used to calculate aridity/humidity index. Then the calculated results of sta- tions were interpolated to land surface using ArcGIS. Results show that the annual average po- tential evapotranspiration is 400―1500 mm in the whole country, 600―800 mm in most parts of it; and 350―1400 mm in growing season (April―Octobor), which is nearly 2.0 mm less than the annual average. According to the aridity/humidity indexes of 1.0, 1.5 and 4.0, the aridity/humidity status is categorized to four types, namely, humid, subhumid, semiarid and arid. A majority of stations (76%) are more humid in growing season than the annual average. Results of com- prisons between the distribution map of aridity/humidity index with that of precipitation and vegetation indicate a good consistence of aridity/humidity status with {2. environment. Therefore potential evapotranspiration calculated with modified FAO’s Penman-Monteith model in combination with aridity/humidity index that considers water balance can more reasonably explain the actual land surface aridity/humidity status of china.

关键词： potential evapotranspiration, aridity/humidity status, land surface, regional differences, Penman-Monteith.

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Seasonal and annual variation of CO_2.flux above a broad-leaved Korean pine mixed forest

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Science china Earth sciences 2006年第S2期49卷 63-73页

作者： ZHANG Junhui, YU Guirui, HAN Shijie, GUAN Dexin & SUN Xiaomin institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, {2. institute of Geographic sciences and natural resources research, chinese academy of sciences, beijing 1.01.1. china institute of Applied Ecology Chinese Academy of Sciences Shenyang China institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing China

Long-term measurement of carbon metabolism of old-growth forests is critical to predict their behaviors and to reduce the uncertainties of carbon accounting under changing climate. Eddy covariance technology was applied to investigate the long-term carbon exchange over a 2.0 year-old chinese broad-leaved Korean pine mixed forest in the Changbai Mountains (12.°2.’E and 42.2.’N, Jilin Province, P. R. china) since August 2.02. On the data obtained with open-path eddy covariance system and CO2.profile measurement system from Jan. 2.03 to Dec. 2.04, this paper reports (i) annual and seasonal variation of FNEE, FGPP and Re; (ii) regulation of environmental factors on phase and amplitude of ecosystem CO2.uptake and release Corrections due to storage and friction velocity were applied to the eddy carbon flux. Lal and soil temperature determined the seasonal and annual dynamics of FGPP and RE separately. VPD and air temperature regulated ecosystem photosynthesis at finer scales in growing seasons. Water condition at the root zone exerted a significant influence on ecosystem maintenance carbon metabolism of this forest in winter. The forest was a net sink of atmospheric CO2.and sequestered -449 g C·m-2.during the study period; -2.8 and -171 gC·m-2.for 2.03 and 2.04 respectively. FGPP and FRE over 2.03 and 2.04 were -1332. -12.4 g C·m-2. and 1054, 112. g C·m-2.respectively. This study shows that old-growth forest can be a strong net carbon sink of atmospheric CO2. There was significant seasonal and annual variation in carbon metabolism. In winter, there was weak photosynthesis while the ecosystem emitted CO2. Carbon exchanges were active in spring and fall but contributed little to carbon sequestration on an annual scale. The summer is the most significant season as far as ecosystem carbon balance is concerned. The 90 days of summer contributed 66.9, 68.9% of FGPp, and 60.4, 62.1% of RE of the entire year.

关键词： old-growth forest eddy-covariance carbon metabolism seasonal and annual dynamics

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geographical Agglomeration of chinese Manufacturing Industries

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chinese Journal of Population,resources and Environment 2007年第2期5卷 3-11页

作者： Zhang Hua 1, 2. Zheng Wei3 1. institute of geographical {2. and natural resources research, chinese academy of sciences, beijing 1.01.1. china 2. Graduate School of the chinese academy of sciences, beijing 100039, china 3. School of Geography, beijing Normal University, beijing 100875, china institute of geographical {2. and natural resources research Chinese Academy of Sciences Beijing 100101 China Graduate School of the chinese academy of sciences Beijing 100039 China School of Geography Beijing Normal University Beijing 100875 China

Based on the plant level data from the First National Census of Basic Units, the Second National Census of Basic Units, and the First National Economic Census of china, this paper ex- amines the geographical agglomeration of {2. manufacturing industries at a more disaggregated level both by industrial classi-fication and spatial unit analysis. Applying the agglomeration index proposed by Maurel and Sedillot, studies show that the most agglomerated industries are resource-intensive, and capital and technology intensive while industries demanding localized inputs or serving localized markets or favored by local governments are fairly dispersed. The more disaggregated industries are more spa- tially agglomerated. At the finer spatial scale, industries are more dispersed. Results indicate that within-county spillovers are stronger than nearby-county spillovers, and within-prefecture spillovers are stronger than nearby prefecture spillovers. Local- ized spillovers are still quite substantial at a range beyond that of counties. Comparing the agglomeration index of {2. manu- facturing industries in 1996, 2.01 and 2.04, agglomeration seems to be a general tendency. Results also indicate that some industries have experienced remarkable changes in their levels of agglom- eration in the period 1996–2.04.

关键词： industrial agglomeration manufacturing industries the MS index

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DESIGN OF FARMLAND GIS FOR PRECISION AGRICULTURE

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chinese geographical Science 2003年第1期13卷 20-24页

作者： AN Kai, XIE Gao-di, LENG Yun-fa, XIAO Yu (institute of geographical {2. and natural resources research, the chinese academy of sciences, beijing 1.01.1. P. R. china) institute of geographical {2. and natural resources research the Chinese Academy of Sciences Beijing 100101 P. R. China

Precision Agriculture, also known as Precision Farming, or Prescription Farming, is a modern agriculture technology system, which brings ' precision' into agriculture system. All concepts of Precision Agriculture are established on the collection and management of variable cropland information. As the tool of collecting, managing and analyzing spatial data, GIS is the key technology of integrated Precision Agriculture system. This article puts forward the concept of Farmland GIS and designs Farmland GIS into five modules, and specifies the functions of the each module, which builds the foundation for practical development of the software. The study and development of Farmland GIS will propel the spreading of Precision Agriculture technology in china.

关键词： precision agriculture farmland GIS site-specific crop management prescription map

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Seasonal variations and environmental control of water use efficiency in subtropical plantation

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Science china Earth sciences 2006年第S2期49卷 119-126页

作者： SONG Xia, YU Guirui, LIU Yunfen, SUN Xiaomin, LIN Yaoming & WEN Xuefa institute of Geographysic sciences and {2. resources research, chinese academy of sciences, beijing 1.01.1. china Graduate University of the chinese academy of sciences, beijing 100049, china institute of Geographysic sciences and {2. resources research Chinese Academy of Sciences Beijing China Graduate University of the chinese academy of sciences Beijing China

To understand the seasonal variations of water use efficiency (WUE) of coniferous plantation in the subtropical monsoon area, the experiment was conducted in 2.03 and 2.04 which presented two distinguished climatic conditions (severe summer drought in 2.03 and normal climatic condition in 2.04). The water stress influenced WUE greatly, which caused a special seasonal WUE pattern. WUE reached the minimum in summer drought and the maximum in winter, which was contrary to the variation of gross primary production (GPP) and canopy evaporation (Fw). In winter, GPP and Fw increased along with the increasing of air temperature and vapor pressure deficit (VPD), with the similar increasing rate. However, in drought summer, there was an adverse trend among GPP/Fw and air temperature and VPD, and the decreasing rate of GPP was far larger than that of Fw. In summer, the conservation of WUE was changed because of the environmental factors, resulting in the decreasing WUE. The photosynthesis and transpiration of vegetation were mainly controlled by the environmental factors in winter, and the impact of stomatal regulation was relatively weak. In summer, Fw was mainly controlled by the stomatal closure and GPP by both environmental factors and stomatal closure.

关键词： water use efficiency gross primary production canopy evapotransplratlon canopy conductance eddy covariance.

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Thresholds of geographic environmental elements in sediment yield of drainage basins

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Science china Earth sciences 2005年第2期48卷 230-240页

作者： CHEN Hao, ZHOU Jinxing, CAI Qiangguo, LU Zhongchen & LI Zhongyan institute of Geographic sciences and {2. resources research, chinese academy of sciences, beijing 1.01.1. china institute of Forestry Science, chinese academy of Forestry Science, beijing 100091, china research Center for Eco-Environment sciences, chinese academy of sciences, beijing 100085, china Computing institute of Science and Engineering, North china Electric Power University, beijing 102.06, china institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing China institute of Forestry Science Chinese Academy of Forestry Science Beijing China research Center for Eco-Environment sciences Chinese Academy of Sciences Beijing China Computing institute of Science and Engineering North China Electric Power University Beijing China

Threshold of environmental elements in drainage basin sediment yield refers to, under effect of climate, underlying surface and human activity, a turning point of abrupt changes in drainage sediment yield related to environmental element characteristics. Previous studies on threshold of sediment yield of relevant drainage basins were mainly concentrated on impact of natural zones with a few researches on impact of other environmental elements. Particularly studies on compound environmental element threshold in drainage basin sediment yield remain blank today. Studies indicate that sediment yield in drainage basins is affected by compound interactions and complex actions. Based on single element analysis, the present paper gives quantitatively compound threshold of environmental elements affecting sediment yield of the drainage basin between Hekouzhen and Tongguan in the middle Yellow River by the method of multi-variant, polynomial formula regression analysis.

关键词： middle Yellow River, environmental element, sediment, sediment delivery mudule, threshold.

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