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

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 Resources Research,Chinese Academy of sciences,{2.,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,{2.,china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Department of Economics and Management Zhejiang Forestry University Linan China center for Chinese agricultural {2. Chinese Academy of Sciences Beijing 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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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 {3. {2.,Chinese Academy of sciences,beijing 100101,china 2.Institute of Geographic sciences 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 center for Chinese agricultural {2. Chinese Academy of Sciences Beijing China Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Research center of the Economy of the Upper Reaches of the Yangtze River Chongqing Technology and Business University Chongqing 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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Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2.3. WANG Pengxin4, YANG Hua1,2.3. LIU Shaomin1,2.3.& WANG Jindi1,2.3.1. Research center for Remote Sensing and GIS, School of Geography, beijing Normal University, beijing 100875, china 2. State Key Laboratory of Remote Sensing Science, beijing 100875, china 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875, china 4. Department of Information Management, College of Information and Electronic Engineering, china agricultural University, beijing 100083. china Research center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing China State Key Laboratory of Remote Sensing Science Beijing China beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing China Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

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Carbon isotope ratios of C_(4) plants in loess areas of North china

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Science china Earth sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2.3. HAN Jiamao 2. ZHOU Liping3. XIONG Xiaogang4, TAN Ming2. WU Zhenhai5 & PENG Jun6 1. Department of Plant Nutrition, {3. agricultural University, {2. 100094, {3. 2. Institute of Geology and Geophysics, Chinese Academy of sciences, {2. 10002., {3. 3. College of Environmental sciences, MOE Laboratory for Earth Surface Processes, Peking University, {2. 100871, {3. 4. Institute of Botany, Chinese Academy of sciences, {2. 100093. {3. 5. Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712.00, {3. 6. Network center, {3. agricultural University, {2. 100094, {3. Department of Plant Nutrition China Agricultural University Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China College of Environmental sciences MOE Laboratory for Earth Surface Processes Peking University Beijing China Institute of Botany Chinese Academy of Sciences Beijing China Northwest Sci-Tech University of Agriculture and Forestry Yangling China Network center China Agricultural University Beijing China

Carbon isotope ratios (δ^(13.C) of 89 C_4 plant samples were determined fromthe loess area in North china. δ^(13.C values vary between -10.5per thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13.C values of C_4 plants show a slight decreasingtrend. The δ^(13.C values of C_4 plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3.species.

关键词： C4 plants, carbon isotope ratios, loess area.

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Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

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Science china(Technological sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3. LI Xiaoying1,2.3. ZHANG Yong1,2.3. ZHAO Feng1,2.3. GU Xingfa1,3.4, ZHU Li1,2.3. WANG Pengxin5 & MIN Xiangjun6 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application, CAS, Bei- jing 100101, china 2. Graduate University of Chinese Academy of {2., beijing 10003., china 3. The center for National Spaceborne Demonstration, beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. College of Information and Electrical Engineering, china agricultural University, beijing 100083. china 6. china center for Resource Satellite Data and Application, beijing 10083., china State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application CAS Beijing 100101 China center for National Spaceborne Demonstration Beijing 100101 China Graduate University Chinese Academy of Sciences Beijing 100039 China Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France College of Information and Electrical Engineering China Agricultural University Beijing 100083 China china center for Resource Satellite Data and Application Beijing 100830 China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.

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Impacts of the Wenchuan Earthquake on the Giant Panda Nature Reserves in china

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Journal of Mountain Science 2010年第2期7卷 197-206页

作者： DENG Xiangzheng JIANG Qunou GE Quansheng YANG LinSheng Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China center for Chinese agricultural {2. Chinese Academy of Sciences Beijing 100101 China Graduate University of the ChineseAcademy of sciences Beijing 100049 China

The Wenchuan Earthquake that occurred in May of 2.08 caused damages to large areas of Sichuan,Gansu,and Shaanxi provinces in *** from local governments and related management agencies show that the giant panda nature reserves in the earthquake-hit areas were heavily *** estimates in this paper of the impacts of the earthquake on the giant panda in the earthquake-hit areas were made based on the interpretation of remote sensing images and information collected by field survey.A rapid assessment method was designed to estimate the damages of the earthquake on giant panda *** using visual interpretation methods,we decoded the remote sensing images of the disaster area in the 49 giant panda nature *** results showed that the Wenchuan Earthquake and the succeeding secondary geological disasters caused great damages to the giant panda nature reserves and disturbed the normal life of the giant pandas there (e.g.,landscape fragmentation increased significantly).Undoubtedly,the life of the giant pandas there was ***,although the earthquake caused certain impacts on the giant pandas,it did not really threat their *** so,we still strongly advocate for protection of the giant pandas,and have prioritized a couple of measures to be taken to restore the giant panda nature reserves in the earthquake-hit areas.

关键词： Wenchuan earthquake Remote sensing Giant panda Giant panda nature reserve Rapid assessment method

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Identification of AtENT3.as the main transporter for uridine uptake in Arabidopsis roots

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Cell Research 2006年第4期16卷 377-388页

作者： Kun Ling Chen~(1,2.*) Min Xin Xu~(2.3.*) Guang Yong Li~(2.3.*) Hui Liang~2.Zong Liang Xia~(2.3. Xin Liu~2.Ji Shu Zhang~1 Ai Min Zhang~2.Dao Wen Wang~2.~1School of Life sciences,Northwest agricultural and Forestry University,Yangling 712.00,{2. ~2.3. for Plant Gene Research({13.)and the State Kev Laboratory of Plant Cell and Chromosome Engineering,Institute of Genetics and Developmental Biology,Chinese Academy of sciences,Datun Road,Chaovang District,beijing 100101,{2. ~3.raduate School of the Chinese Academy of sciences,Yuquan Road,Shijingshan District,{13. 10003.,{2. School of Life sciences Northwest Agricultural and Forestry University Yangling China center for Plant Gene Research (beijing) and the State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology Chinese Academy of Sciences Datun Road Chaoyang District Beijing China Graduate School of the Chinese Academy of sciences Yuquan Road Shijingshan District Beijing China

Previous studies have shown that Arabidopsis equilibrative nucleoside transporters （AtENTs） possess transport activitieswhen produced in yeast cells and are differentially expressed in Arabidopsis ***,we report further analysis onthe nucleoside transport activities and transcriptional patterns of AtENT *** recombinant proteins of AtENTs3.6,and 7,but not those of AtENTs 1,2.4,and 8,were found to transport thymidine with high *** to previ-ous suggestion that AtENT1 may not transport uridine,this work showed that recombinant AtENT1 was a pH-dependentand high-affinity transporter of *** grown on MS plates,the AtENT3.knockout plants were more tolerant tothe cytotoxic uridine analog 5-fluorouridine than wild-type plants and the knockout plants ofAtENT 1 or ***-sistent with this observation,the AtENT3.knockout line exhibited a significantly decreased ability to take up [3.]uridinevia the roots when compared with wild-type plants and the plants with mutated AtENT 1 or *** indicates thatAtENT3.but not AtENTs 1 and 6,is the main transporter for uridine uptake in Arabidopsis *** transcription ofAtENTs 1,3.4,6,7,and 8 was regulated in a complex manner during leaf development and *** contrast,thesix AtENT members were coordinately induced during seed *** work provides new information on thetransport properties of recombinant AtENT proteins and new clues for future studies of the in vivo transport activitiesand physiological functions of the different ENT proteins in Arabidopsis plants.

关键词： Arabidopsis equilibrative nucleoside transporter expression pattern nucleoside transport functional analysis

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2.5-dimensional angle potential field algorithm for the real-time autonomous navigation of outdoor mobile robots

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Science china(Information sciences) 2011年第10期54卷 2100-2112页

作者： QIU Quan 1,3.& HAN JianDa 2.1 beijing Research center of Intelligent Equipment for Agriculture,beijing 100097,china 2.State Key Laboratory of Robotics,Shenyang Institute of Automation,Chinese Academy of sciences,Shenyang 110016,china 3.National Research center for Intelligent agricultural Equipment,beijing 100097,china beijing Research center of Intelligent Equipment for Agriculture Beijing China National Research center for Intelligent agricultural Equipment Beijing China State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang China

A new real-time algorithm for the autonomous navigation of mobile robots equipped with laser scanners is proposed in this *** from the existing algorithms designed for 2.dimensional navigation problems,the new algorithm introduces the height information of the obstacles into the guidance process and behaves as a 2.5-dimensional angle potential field algorithm (2.5D-APF) to fulfill the navigation requirements under complex outdoor terrain ***,one laser scan is partitioned into two kinds of function sectors: guidance sector and inspecting ***,the guidance sector and the inspecting sectors are reconstructed to form a virtual guidance scan,where the 2.5D information is taken into ***,the conventional APF is improved to analyze the virtual guidance scan and generate the navigation *** new algorithm is tested on a tracked mobile robot,and the experimental results validate the proposed algorithm.

关键词： robot 2.5-dimensional outdoor real-time autonomous navigation

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Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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Science china(Technological sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2. HUANG GuanHua1,2.& QU ZhongYi3.1 center for Agriculture Water Research, {3. {2. University, beijing 100083. {3. 2.Chinese-Israeli International center for Research and Training in Agriculture, {3. {2. University, beijing 100083. {3. 3.Water Conservancy and Civil Engineering College, Inner Mongolia {2. University, Hohhot 010018, {3. center for Agriculture Water Research China Agricultural University Beijing China Chinese-Israeli International center for Research and Training in Agriculture China Agricultural University Beijing China Water Conservancy and Civil Engineering College Inner Mongolia Agricultural University Hohhot China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

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The new interpretation of support vector machines on statistical learning theory

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Science china Mathematics 2010年第1期53卷 151-164页

作者： ZHANG ChunHua 1 , TIAN YingJie 2.& DENG NaiYang 3.1 School of Information, Renmin University of china, beijing 100872. china 2.Research center on Fictitious Economy and Data Science, Chinese Academy of sciences, beijing 100080, china 3.College of Science, china agricultural University, beijing 100083. china School of Information Renmin University of China Beijing China Research center on Fictitious Economy and Data Science Chinese Academy of Sciences Beijing China College of Science China Agricultural University Beijing China

This paper is concerned with the theoretical foundation of support vector machines (SVMs). The purpose is to develop further an exact relationship between SVMs and the statistical learning theory (SLT). As a representative, the standard C-support vector classification (C-SVC) is considered here. More precisely, we show that the decision function obtained by C-SVC is just one of the decision functions obtained by solving the optimization problem derived directly from the structural risk minimization principle. In addition, an interesting meaning of the parameter C in C-SVC is given by showing that C corresponds to the size of the decision function candidate set in the structural risk minimization principle.

关键词： C-support vector classification the minimization principle of the structural risk KKT conditions

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