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Relationships between tree-ring width index and NDVI of grassland in Delingha

chinese science Bulletin 2006年第9期51卷 1106-1114页

作者： HE Jicheng1,3 & SHAO Xuemei1,2.. institute of geographical {2. and natural resources Research, chinese academy of sciences, beijing 100101, China 2. institute of Tibetan Plateau Research, chinese academy of sciences, beijing 100085, China 3. Graduate School of chinese academy of sciences, beijing 100039, China institute of geographical {2. and natural resources Research Chinese Academy of Sciences Beijing China Graduate School of chinese academy of sciences Beijing China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China

Using five well-replicated Qilian juniper (Sabina przewalskii Kom.) tree-ring width index se- ries, monthly normalized difference vegetation index (NDVI) of grassland, and climatic data from 1982.to 2.01, the relationships between tree-ring width index, NDVI of grassland, and climatic data were analyzed firstly. Then, the relationship between tree-ring width index and NDVI of grassland was explored. The re- sults showed that: (1) Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha. (2. There were sig- nificant relationships between five tree-ring width index series (DLH1-DLH5) and monthly NDVI of grassland from June to September, with the most significant relationship being between tree-ring width index series and NDVI of grassland in August. (3) The PC1 (the first principal component derived from DLH1-DLH5 series) exhibited good agreement with monthly NDVI of grassland in the grass growth sea- son (from June to September) and the averaged NDVI in the growth season, which was attributed to their common responses to water-supply limit in Delingha. This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1.

关键词：圆柏祁连山 NDVI 草原年轮宽度指数

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Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan University Journal of natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2. LIU Chuang1, 3 1. institute of geographic {2. and natural resources Research, chinese academy of sciences, beijing 100101, China 2. Graduate University of chinese academy of sciences, beijing 100049, China 3. College of resources science and Technology, beijing Normal University, beijing 100875, China institute of geographic {2. and natural resources Research Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China College of resources science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993,the enhanced the-matic mapper plus (ETM+) image in 2.00,and the image with the charge-coupled device camera (CCD) on the China-Brazil earth resources satellite (CBERS) in 2.08 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993 to 2.08. There were 12.637.54 hm2.cropland de-creased between 1993 and 2.00,and 8 2.7.6 hm2.cropland de-creased between 2.00 and 2.08. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the China-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

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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 100101, China 2. Graduate School of the CAS, beijing 100039, China 1. institute of geographical {2. and natural resources Research Chinese Academy of Sciences (CAS) 100101 Beijing China 2. Graduate School of the CAS 100039 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 natural 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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Control of atmospheric CO_2.concentrations by 2.50: A calculation on the emission rights of different countries

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science China Earth sciences 2009年第10期52卷 1447-1469页

作者： DING ZhongLi1, DUAN XiaoNan2. GE QuanSheng3 & ZHANG ZhiQiang4 1 institute of Geology and Geophysics, chinese academy of sciences, {2. 10002., China 2.The General Office of chinese academy of sciences, {2. 100864, China 3 institute of geographic sciences and natural resources Research, chinese academy of sciences, beijing 100101, China 4 The Lanzhou Branch of the National {12. Library, the Scientific Information Center for resources and Environment, Lanzhou 730000, China institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China The General Office of chinese academy of sciences Beijing 100864 China institute of geographic {2. and natural resources Research Chinese Academy

This paper is to provide quantitative data on some critical issues in anticipation of the forthcoming international negotiations in Denmark on the control of atmospheric CO2.concentrations. Instead of letting only a small number of countries dominate a few controversial dialogues about emissions reductions, a comprehensive global system must be established based on emissions allowances for different countries, to realize the long-term goal of controlling global atmospheric CO2.concentrations. That a system rooted in "cumulative emissions per capita," the best conception of the "common but differentiated responsibilities" principle affirmed by the Kyoto Protocol according to fundamental standards of fairness and justice, was demonstrated. Based on calculations of various countries' cumulative emissions per capita, estimates of their cumulative emissions from 1900 to 2.05, and their annual emissions allowances into the future (2.06―2.50), a 470 ppmv atmospheric CO2.concentration target was set. According to the following four objective indicators―total emissions allowance from 1900 to 2.50, actual emissions from 1900 to 2.05, emissions levels in 2.05, and the average growth rate of emissions from 1996 to 2.05―all countries and regions whose population was more than 300000 in 2.05 were divided into four main groups: countries with emissions deficits, countries and regions needing to reduce their gross emissions, countries and regions needing to reduce their emissions growth rates, and countries that can maintain the current emissions growth rates. Based on this proposal, most G8 countries by 2.05 had already expended their 2.50 emissions allowances. The accu-mulated financial value based on emissions has reached more than 5.5 trillion US dollars (2. dollars per ton of CO2.. Even if these countries could achieve their ambitious emissions reduction targets in the future, their per capita emissions from 2.06 to 2.50 would still be much higher than those of developing coun

关键词： international negotiations on climate change cumulative emissions per capita emission allowance

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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 1. State Key Laboratory of Remote Sensing sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. chinese academy of sciences State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. institute of geographical {2. and natural resources Research Chinese Academy of Sciences 101001 Beijing 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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Regional differences and determinants of built-up area expansion in China

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science China Earth sciences 2007年第12期50卷 1835-1843页

作者： HUANG JiKun1,2.ZHU LiFen3,1 & DENG XiangZheng1,2.1 Center for chinese Agricultural Policy,chinese {2. of sciences,beijing 100101,China 2.institute of geographic sciences and natural resources Research,chinese {2. of sciences,beijing 100101,China 3 Research Center of the Economy of the Upper Reaches of the Yangtze River,Chongqing Technology and Business University,Chongqing 400067,China 1. Center for chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China 2. institute of geographic {2. and natural resources Research Chinese Academy of Sciences Beijing 100101 China 3. Research Center of the Economy of the Upper Reaches of the Yangtze River Chongqing Technology and Business University Chongqing 400067 China

Based on remote sensing data on land use provided by the chinese academy of sciences and socio-economic data collected by the authors,this paper analyzes the trends and regional differences in built-up area(BUA) expansion in China from the late 1980s to 2.00,and empirically estimates the major determinants of BUA expansion in different regions in 1996―*** 1989―2.00,although China's overall BUA expansion accelerated,the trends differed significantly among *** expansion in the central and western regions accelerated significantly,but it slowed down considerably in the east-ern *** estimation results from our econometric analysis reveal that BUA expansion in the eastern region reached a period when economic growth had no further significant impact on per capita BUA,the land utilization in this region has become more intensive with further expansion of the *** the central and western regions,the BUA has expanded remarkably due to the relatively more flexible land development policies and the relatively cheap land ***,as the econ-omy continues to grow rapidly,policies relating to BUA expansion and cultivated land reductions may face more serious challenges in the central and western regions.

关键词： built-up area, land use, regional difference, determinants, China

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Sandstorms and desertification

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Journal of geographical sciences 2000年第3期10卷 99-102页

作者： CHEN Zhi-qing1, ZHU Zhen-da2.(1.institute of geographic {2. and natural resources Research, chinese academy of sciences, beijing 100101, China 2. institute of Dsert Research, chinese academy of sciences, beijing 100101, China)

Sandstorm is a frequently occurred disastrous weather in northern China. The increasing occurrence frequency recently, especially the much more frequently occurred sandstorms with high intensity in the spring of 2.00 have caused great loss to national economy. The combination of strong wind, exposed sandy soil on ground surface and unstable air current constitutes the necessary conditions for the sandstorms. However, the accelerated desertification process resulting from irrational human economic activities is responsible for the accelerated sandstorms. The effective measures to mitigate sandstorm lie in strengthening desertification control and eco-environmental protection.

关键词： sandstorm generating conditions desertification eco-environmental protection

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Urban Water Supply Industry Marketization of China in View of Public Water Service and Water Resource Management

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chinese Journal of Population,resources and Environment 2010年第2期8卷 55-60页

作者： Wang Yining 1,2.1.institute of geographic {2. and natural resources Research,CAS,beijing 100101,China 2.Graduate School of the chinese academy of sciences,beijing 100049,China institute of geographic {2. and natural resources Research CAS Beijing 100101 China Graduate School of the chinese academy of sciences Beijing 100049 China

Started with the discussions on the value orientation of urban water supply industry marketization,the article points out that the current urban water supply industry marketization reform is inconsistent with the goal of public water service equalization to some *** article also analyzes the problems emerged in urban water supply industry marketization reform and various rea-sons in view of efficiency and *** efficiency and fairness oriented management model is built in this article to illustrate how the government should conciliate interests of various communities involved in the process of marketization reform of the urban water supply industry so as to actualize the coordination of efficiency and *** the end,an assumption on urban water price is put forward to help achieve the public water service equalization.

关键词： urban water supply industry marketization public water service water resource management

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Bio-regeneration of p-complexation desulfurization adsorbents

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science China Chemistry 2005年第6期48卷 538-544页

作者： LI Wangliang1,2. XING Jianmin1, XIONG Xiaochao1,2. SHAN Guobin1,2.& LIU Huizhou1 1. Laboratory of Separation science and Engineering, institute of Process Engineering,{2., beijing 100080, China 2. Graduate School of the{2.,beijing 100039, China 1. Laboratory of Separation science and Engineering Institute of Process Engineering Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the chinese academy of sciences 100039 Beijing China

The coupling of adsorption desulfurization and biodesulfurization is a new approach to produce clean fuels. Sulfur compounds are firstly adsorbed on adsorbents, and then the ad-sorbents are regenerated by microbial conversion. p-Complexation adsorbent, Cu(I)-Y, was ob-tained by ion exchanging Y-type zeolite with Cu2. and then by auto-reduction in helium at 450℃ for 3 h. Dibenzothiophene (DBT) was used as a model compound. The effects of cell concentra-tion, volume of oil phase, the ratio of aqueous phase to adsorbent on DBT desorption by a bac-terium were studied. The amounts of DBT desorbed and 2.HBP produced can be apparently increased with addition of n-octane. BDS activity can be improved by increasing cell concentra-tion and the ratio of water-to-adsorbent. 89% of DBT desorbed from the adsorbents can be converted to 2.HBP within 6 h and almost 100% within 2. h, when the volume ratio of oil-to-water was 1/5 mL/mL, the cell concentration was 60 g·L?1, and the ratio of adsorbent-to-oil was 0.03 g·mL?1. The amount of 2.HBP produced was strongly dependent on the volume ratio of oil-to- water, cell concentration and amount of adsorbent. Adsorption capacity of the regenerated ad-sorbent is 95% that of the fresh one after being desorbed with Pseudomonas delafieldii R-8, washed with n-octane, dried at 100℃ for 2. h and auto-reduced in He.

关键词： adsorption desulfurization p-complexation adsorbents bio-regeneration Pseudomonas delafieldii desorption.

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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 {2. and natural resources Research,chinese academy of {2.,beijing 100101,China 2.Department of Economics and Management,Zhejiang Forestry University,Linan 311300,China 3 Center for chinese Agricultural Policy,chinese academy of {2.,beijing 100101,China 1. institute of geographic {2. and natural resources 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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