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Process and mechanism of arable land change in Hebei Province during the past 50 years

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Journal of geographical sciences 2001年第4期11卷 47-52页

作者： XU Yue-qing (institute of geographical sciences and natural resources research, CAS, Beijing 100101, China College of resource and Environment Science, Hebei Normal University, Shijiazhuang 050016, China ) CAS Institute of Geographical Sciences and Natural Resources Research Beijing China (GRID:grid.9227.e) (ISNI:***) Hebei Normal University College of Resource and Environment Science Shijiazhuang China (GRID:grid.256884.5) (ISNI:***)

Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with population growth has become a serious problem, which has restricted regional sustainable *** paper revealed the basic process, regional differences of change and the gravity center of arable land area according to the long-series statistical data of arable land during the past 50 years. On the basis of the above mentioned, the major driving forces that influence the changes of the arable land are discussed. The research results indicate that there is a trend of obvious fluctuating decrease in arable land area during the last 50 years. The changes of arable land area undergo the process from increase to sharp decrease to gently decrease. The regional disparity of change in arable land area is very notable and the gravity center of arable land area moves to the northeast 49.22 km. Regarding the decrease in arable land, the direct driving forces include adjustments of agricultural structure and reclamation, and indirect driving forces include advance in technology, economic interest and population growth etc.

关键词： decrease in arable land area changing process mechanism Hebei Province

Improving the accuracy of image-based forest fire recognition and spatial positioning

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Science China(Technological sciences) 2010年第S1期53卷 184-190页

作者： JIANG LiLi 1,QI QingWen 1,ZHANG An 1,GUO ChaoHui 2 & CHENG Xi 1,3 1 institute of geographical sciences and natural resources research,Chinese Academy of sciences,Beijing 100101,China 2 China Center for resources Satellite Data and Applications,Beijing 100094,China 3Graduate University of Chinese Academy of sciences,Beijing 100049,China Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China China Ctr resources Satellite Data & Applicat Beijing 100094 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

Forest fires are frequent natural *** is necessary to explore advanced means to monitor,recognize and locate forest fires so as to establish a scientific system for the early detection,real-time positioning and quick fighting of forest *** paper mainly expounds methods and algorithms for improving accuracy and removing uncertainty in image-based forest fire recognition and spatial ***,we discuss a method of forest fire recognition in visible-light *** are four aspects to improve accuracy and remove uncertainty in fire recognition:(1)eliminating factors of interference such as road and sky with high brightness,red leaves,other colored objects and objects that are lit up at night,(2)excluding imaging for specific periods and azimuth angles for which interference phenomena repeatedly occur,(3)improving the thresholding method for determining the flame border in image processing by adjusting the threshold to the season,weather and region,and (4)integrating the visible-light image method with infrared image ***,we examine infrared-image-based methods and approaches of improving the accuracy of forest fire recognition by combining the spectrum threshold with an object feature value such as the normalized difference vegetation index and excluding factors of disturbance such as interference signals,extreme weather and high-temperature ***,a method of visible analysis to enhance the accuracy of forest fire positioning is examined and realized;the method includes decreasing the visual angle,selecting central points,selecting the largest spots,and judging the selection of fire spots according to the central *** studies are examined and the results are found to be satisfactory.

关键词： forest fire monitoring spatial positioning accuracy improvement

STUDY ON DEVELOPMENT STRATEGY OF SHIPPING CENTERS AND TRANSPORTATION NETWORKS IN THE YELLOW SEA RIM

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Chinese geographical Science 2003年第2期13卷 97-103页

作者： JIN Feng-jun (institute of Geographic sciences and natural resources research, Chinese Acad emy of sciences, Beijing 100101, P.R. China) institute of Geographic sciences and natural resources research Chinese Academy of Sciences Beijing 100101 P. R. China

It is very important to establish cooperative mechanism to guarantee allmembers to develop their e-conomies in the Yellow Sea Rim. In this paper, the development strategiesof shipping centers and transportation network are discussed based on economic globalizationtendency. The results argue that a united transportation network should be built in order to promotethe economic competition of Northeast Asia in the world. As a key component of the economiccooperation, a hierarchical shipping centers network should be established with Hong Kong, Shanghai,Pusan, Kobe, and Tokyo as cores. The authorities of China, Japan, R. 0. Korea and D. P. R. Koreashould make more efforts to build a set of cooperation institutions based on raising thetransportation efficiency.

关键词： the yellow sea rim shipping center transportation network hub-and-spoke system

Optimization of mathematical models for thematic maps

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Science China(Technological sciences) 2010年第S1期53卷 15-24页

作者： QI QingWen1,ZHANG An1,JIANG LiLi1,ZOU XiuPing2,XU Li3 & CHENG Xi1,4 1 institute of geographical sciences and natural resources research,Chinese Academy of sciences,Beijing 100101,China 2.institute of Policy and Management,Chinese Academy of sciences,Beijing 100080,China 3 Taishan University,Taian 271021,China 4 Graduate University of Chinese Academy of sciences,Beijing 100049,China Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Chinese Acad Sci Inst Policy & Management Beijing 100080 Peoples R China Taishan Univ Tai An 271021 Shandong Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

The thematic map is a major class of maps designed to demonstrate particular features or concepts,functioning as an indispensable tool in geographical *** process of thematic mapping is one into which geographical research goes deeply and *** key activity and course of thematic map production is the use of mathematical models to create thematic data ***,the selection and optimization of mathematical models is in the forefront of thematic map *** theoretical foundations,mechanisms and methods of mathematical model optimization are expounded in this paper,including two approaches,the phase by phase mode and the multi-aim scheme balance *** studies in eco-environment mapping and emergency mapping are described and analyzed,with a hierarchical analysis method being used in the model optimization for eco-environment fragility and sensitivity assessment mapping in Beibuwan (Guangxi) District,the dynamic system (DS) method being used in the model optimization for ecological security adjustment mapping in Xishuang Banna,Yunnan province,and the multi-phase mode being used in the models for forest fire and infectious diseases mapping.

关键词： thematic map mathematic model optimization

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

geographical Agglomeration of Chinese Manufacturing Industries

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中国人口·资源与环境：英文版 2007年第2期5卷 3-11页

作者： Zhang Hua 1, 2, Zheng Wei3 1. institute of geographical sciences and natural resources research, Chinese Academy of sciences, Beijing 100101, 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 sciences 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 Chinese 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 Chinese manu- facturing industries in 1996, 2001 and 2004, 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 1996–2004.

关键词： industrial agglomeration manufacturing industries the MS index

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 natural resources research, CAS, Beijing 100101, China) institute of Geographic sciences and natural 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

Interannual and Interdecadal Variability of Atmospheric Water Vapor Transport in the Haihe River Basin

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Pedosphere 2005年第5期15卷 585-594页

作者： WEI Jie LIN Zhao-Hui XIA Jun TAO Shi-Yan institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 （China） institute of geographical sciences and natural resources research Chinese Academy of Sciences Beijing 100044（China）

The seasonal mean atmospheric precipitable water and water vapor transport over the Haihe River Basin （HRB） in North China with a focus on their interannual to interdecadal variability, and then the relationships of the interannual and interdecadal variability of the water cycle over the HRB to the Pacific Decadal Oscillation （PDO） and E1 Nino-Southern Oscillation （ENSO） phenomena were investigated using the observational and National Centers for Environmental Prediction （NCEP） reanalysis data. There was a strong interdecadal variability for the water cycle （such as precipitation and water vapor transport） over the region, with an abrupt change occurring mostly in the mid 1970s. The intensity of the East Asian summer monsoon largely affected the atmospheric water vapor transport. Generally, the net meridional convergence of the water vapor flux over the region was relatively large before 1965, and it declined gradually from then on with a further notable decrease since mid 1970s. Zonal water vapor transport was similar to meridional, but with a much smaller magnitude and no noteworthy turning in the mid 1970s. Results also suggested that the wind field played an important role in the water vapor transport over the HRB before the mid 1960s, and the interdecadal variability of the water cycle （precipitation, water vapor transport, etc.） in the summer was related to the PDO; however, interannual variation of the water vapor transport could also be related to the ENSO phenomena.

关键词： interannual variability interdecadal variability Haihe River Basin water vapor transport

Relationship between precipitation and the infiltration depth over the middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley

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Progress in natural Science:Materials International 2008年第9期18卷 1123-1128页

作者： Zhixin Hao a, Jingyun Zheng a, Quansheng Gea,, Xifeng Guoa,b a institute of geographical sciences and natural resources research, Chinese Academy of sciences, 11A, Datun Road Anwai, Chaoyang District, Beijing 100101, China b Graduate University of Chinese Academy of sciences, Beijing 100049, China institute of geographical sciences and natural resources research Chinese Academy of Sciences 11A Datun Road Anwai Chaoyang District Beijing 100101 China Graduate University of Chinese Academy of sciences Beijing 100049 China

The purpose of the paper is to extract and make the best use of rainfall information contained in the Chinese historical archives of Qing Dynasty, and reconstruct the precipitation series during *** study followed the Yu-Fen-Cun (rainfall infiltration depth) observation method in Qing Dynasty, to conduct soil infiltration experiment under the natural rainfall conditions during *** related parameters, such as precipitation, intensity, initial soil moisture content and infiltration depth have been measured at 10 stations (east of 105°E, 30°-40°N) with representative climatic conditions and soil physical texture in the middle and lower reaches of the Yellow River and Yangtze-Huaihe River *** statistical results indicate that precipitation is the primary infiuencing factor to infiltration depth and is positively correlated with the infiltration ***, the efiects of every factor on infiltration depth are significantly difierent between the middle and lower reaches of the Yellow River and Yangtze-Huaihe River ***, the relationship equations of precipitation and infiltration depth are established for each site, most of which can pass over 60% of the variance explanations and provide quantitative models to reconstruct the precipitation series using Yu-Fen-Cun records in Qing Dynasty.

关键词： Middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley Precipitation Infiltration depth Yu-Fen-Cun Climate reconstruction