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CH_4 uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,china

Science china Earth sciences 2010年第7期53卷 977-983页

作者： GENG YuanBo1, LUO GuangQiang1,2 & YUAN GuoFu1 1 institute of Geographic sciences and natural {3. research, chinese academy of sciences, beijing 100101, china 2 Graduate University of chinese academy of sciences, beijing 100049, china 1. institute of Geographic sciences and natural {3. research Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The influence of near ground atmosphere CH4 concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4 uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, china. The results showed that CH4 uptake flux was positively correlated with near ground atmosphere CH4 concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4 flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.52 (natural conditions, 1.51 (aboveground plants were excluded), and 2.00 mg m?2 d?1 (all plants were removed), respectively. The difference between the CH4 flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4 uptake flux is smaller than that of roots or roots-removing process. CH4 uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.3.–7.86). The Leymus chinensis steppe acts as a sink for CH4, and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method

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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 {3. research, chinese Acad emy of sciences, beijing 100101, P.R. china) institute of Geographic sciences and natural {3. 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

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Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in china

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Science china Earth sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1,2,3.HUANG JiKun 1,3.& DENG XiangZheng 1,3.1 institute of Geographic sciences and natural {3. research,chinese academy of sciences,beijing 100101,china 2 Department of Economics and Management,Zhejiang Forestry University,Linan 3.13.0,china 3.Center for chinese Agricultural Policy,chinese academy of sciences,beijing 100101,china 1. institute of Geographic sciences and natural {3. research Chinese Academy of Sciences Beijing 100101 China2. Department of Economics and Management Zhejiang Forestry University Linan 311300 China3. Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China

As a renewable energy,biofuel has attracted great attention in china and the rest of *** with the national food security,china recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote sensing data on land use,data on meteorological,soil and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in china's major Jatropha curcas production region,Southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation Southwest china

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Relationship between Surface Pollen and Modern Vegetation in Southwestern china

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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 {3. 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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Analysis and Modeling on the Spatial Structure of Urban Land Use: A Case of Jinan, china

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chinese Journal of Population,resources and Environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1, 3. Zhang Zulu2, Jiang Luguang 1 1. institute of geographical sciences and {3. resources research, chinese academy of sciences, beijing 100101, china 2. College of Population, resources and Environment, Shandong Normal University, Jinan Shandong 250014, china 3. Graduate School of the chinese academy of sciences, beijing 10003., china institute of geographical sciences and {3. resources research Chinese Academy of Sciences Beijing 100101 China Graduate School of the chinese academy of sciences Beijing 100039 China College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1986 and 2004, the spatial structure of Jinan is studied in this paper with the method of Geographic Information System (GIS). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 50%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1986 to 2004, great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure Jinan

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ANALYSIS OF DRIVING FORCES ON THE CHANGE OF HISTORICAL FARMLAND USE IN SHANDONG PROVINCE DURING THE QING DYNASTY (1644-1911)

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chinese geographical Science 2003年第3期13卷 207-215页

作者： ZHANG Xue-in, GE Quan-heng, ZHENG Jing-un(institute of Geographic sciences and natural {3. research, chinese academy of sciences, beijing 100101, P. R. china) institute of Geographic sciences and natural {3. research Chinese Academy of Sciences Beijing P. R. China

How land-cover has been changed by human use over the last 3.0 years is oneof the five overarching questions guiding the Land-use/Cover Change (LUCC) Science/research *** has variety of historical documents providing unique data superiority. So the characteristicsof farmland area in Shandong Province during the Qing Dynasty (1644-1911) are summarized firstly: 1)the rising trend of farmland area was striking; 2) farmland area had remarkable fluctuation; 3.farmland area per capita decreased dramatically; 4) wasteland reclamation index increased ***, the driving forces of farmland area change are analyzed. It is concluded that natural andhuman factors are jointly influential. Among the driving forces, human dimensions are the mainfactors of farmland area change, which direct the general tendency of the changes mentioned *** the natural factors influence the stability of farmland area as well. Variation of the naturalfactors would act as the major contributory factor to farmland area change during years or periodsof abrupt climatic changes, or during the intensive occurring periods of natural hazards. Besides,the passive aspects of human factors, such as war chaos also influenced the fluctuation of thefarmland area. This research indicates that it is feasible to study the land-use/cover change bychinese historical literatures, which has huge potential to provide a comprehensive picture of thegrowing dominance of human land-use and land-cover patterns that can be used in many global changeresearch projects.

关键词： farmland driving forces shandong province qing dynasty

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The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china Earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3. ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. institute of Geographic sciences and natural {3. research, chinese academy of sciences, beijing 100101, china 2. Department of Geography, Nanjing University, Nanjing 210093. china 3. School of Earth sciences and {3., china University of Geosciences, beijing 100083. china institute of Geographic sciences and natural {3. research Chinese Academy of Sciences Beijing 100101 China Department of Geography Nanjing University Nanjing 210093 China School of Earth sciences and resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (3.) and minor-scale (10-3.10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

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Continuous wavelet transform and discrete multi-resolution analysis of surface fluxes and atmospheric stability

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Progress in natural Science:Materials International 2006年第4期16卷 403-409页

作者： JIANG Zhaoyang, YU Qiang, WANG Tianduo, SUN Xiaomin and ZHANG Renhua Shanghai institute of Plant Physiology and Ecology, chinese academy of sciences, Shanghai 20003., china institute of Geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, china [a]Shanghai institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai China [b]institute of Geograhpic sciences and natural {3. research Chinese Academy of Sciences Beijing China

Variations of land surface fluxes of sensible heat (H), latent heat (LE), and CO2(F-CO2) obtained from the eddy-co-variance measurements above a winter wheat field from March 3. to April 24, 2001 have been studied at scales ranging from 10 minutes to days. Wavelet transform is used in the analysis of land surface fluxes and atmospheric stability (ξ) calculated from the measurements to reveal the changes in land surface fluxes in hours to days scales. The main results are: (1) Concise and compact information about the fluxes, net radiation (Rn), temperature ( T) and ξ in the scale-time domain are extracted from the data by continuous wavelet analysis, and 1 day, 0.5 day and short-period (shorter than 0.5 day) components are revealed. Continuous wavelet coefficients can be used to characterize periodic components of changes in fluxes and ξ. (2) Discrete-time multi-resolution analysis can be used to concentrate total energy variance of time series of the measurements to a small number of coefficients, plotting the relative energy distribution to get several meaningful characteristics of the data. (3. Under neutral atmospheric conditions, the relative energy distributions of the Haar multi-resolution analysis of the three non-dimensional coefficients ( T/T* , q/q * and c/c * ) display clear similarities.

关键词： atmospheric stability flux continuous wavelet transform multi-resolution wavelet analysis.

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

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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 10003.,china 2 {3. 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 {3. 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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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.{3. 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 {3. 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 {3., 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 {3. 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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