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chinese forest Eco-Network System

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chinese forestry Science and Technology 2002年第1期1卷 26-32页

作者： PENG Zhenhuachinese academy of forestry, beijing 100091. china

Based on the current status of nature, economy and society, and in the light of interconnected patterns of material, energy and information flows, the forest Eco-Network System in china (CFENS) is to be established to harmonizes the development of human, nature and society in this country, which is of integrity, multi-function, high efficiency and operability, and views the whole mainland as an ecosystem with different big parches consisting of different types of forests, grasslands, flelds, barren hill...

关键词： forest eco-network system sustainable development

Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

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Progress in Natural Science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2 and Luo Zhexian2(1. institute of Atmospheric Physics, chinese academy of Sciences, beijing 100029, china 2. Nanjing University of information Sciences & Technology, Nanjing 210044, china) institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Nanjing University of information Sciences & Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 1200 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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Science china Earth Sciences 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2, DU Andao1, LU Jiren3, QU Wenjun1 & CHEN Jiangfeng2 1. National Research Center of Geoanalysis, beijing 100037, china 2. Laboratory for Earth Material Cycling, School of Earth and Space Sciences, University of Science and Technology of china, Hefei 230026, china 3. institute of Mineral resource, chinese academy of Geological Sciences, beijing 100037, china National Research Center of Geoanalysis beijing china Laboratory for Earth Material Cycling School of Earth and Space Sciences University of Science and Technology of China Hefei China institute of Mineral resource chinese academy of Geological Sciences beijing china

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 833 ± 35 Ma, initial 187Os/188Os ratio of 0.279 ± 0.018 (MSWD = 1.7) and γOs = 130 ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 827 ± 8 Ma (n=5, MSWD = 4.3). The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

Soil erosion types in the loess hill and gully area of china

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Journal of Environmental Sciences 1995年第3期7卷 266-272页

作者： Fu Bojie(Research Center for Eco-Environmental Sceiences, chinese academy of Sceiences, Seeijing 100085, china)Wang Xilin(Department of Water and Soil Conservation, beijing forestry University, beijing 100083, china)Hubert Gulinck(institute for Land and W

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关键词： soil erosion type geographical information system loess hill and gully area.

A study of spaceborne SAR raw data compression error based on a statistical model of quantization interval transfer probability

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Science china(information Sciences) 2010年第11期53卷 2352-2362页

作者： LI Xin1,2,3*, QI HaiMing1,2*, HUA Bin1,2,3, LEI Hong1 & YU WeiDong1 1institute of Electronics, chinese academy of Sciences, beijing 100190, china 2The National Key Laboratory of Microwave Imaging Technology, beijing 100190, china 3Graduate University, chinese academy of Sciences, beijing 100039, china 1. institute of Electronics Chinese Academy of Sciences Beijing 100190 China2. The National Key Laboratory of Microwave Imaging Technology Beijing 100190 China3. Chinese Academy of Sciences Graduate University Beijing 100039 China

SAR raw data signal to noise ratio (SNR) after compression is of great importance since the choice of compression ratio is dependent on it during SAR system design and application analysis. The signal to quantization noise ratio (SQNR) generally used may not precisely indicate the relationship between signal and noise. Considering the thermal noise, a statistical model of quantization interval transfer probability is proposed in this paper. SNR mapping between SAR raw data before analog to digital converter (ADC) and after block adaptive quantization (BAQ) over the whole set of saturation degree is obtained using this model. When the power of echo is small with low SNR, after 1, 2, 3 or 4 bits BAQ compression, SNR has tiny difference among the four compression levels. When the power of the echo is medium with higher SNR, the SNR degradation after BAQ is about 5 dB with each bit decreasing from 4 bits. If voltage of the echo is higher than the clipping point of ADC, SNR after ADC and BAQ degrades stepwise. The higher the saturation degree of SAR raw data, the worse the SNR is. Simulated Gaussian data and real SAR raw data are used to verify the theoretical results, which are useful in the choice of BAQ compression ratio and further application analysis.

关键词： SAR raw data compression SNR saturation

Revelation from Management System Reform of State-owned forests of Hessen State in Germany

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chinese forestry Science and Technology 2008年第1期7卷 31-35页

作者： LIU Yong LI Zhiyong YE Bing Research institute of forestry Policy and information, chinese academy of forestry, beijing 100091, P. R. china

The paper analyzes the management system reforms of state-owned forest in Hessen State of Germany based on the forestry situation, and draws conclusions which can be used for reference in management system reform of state-owned forest in china. The results are as follows: stepwise reform is the mode, ecology-centeredness is the principle, transparent property right is the precondition, detached function of government and forest industry groups is the key, and integrated law and regulation system is the guarantee.

关键词： state-owned forest management system reform Hessen state Germany

Next-generation sequencing technology:A technology review and future perspective

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Science china(Life Sciences) 2010年第1期53卷 44-57页

作者： ZHOU XiaoGuang1,REN LuFeng1,LI YunTao2,ZHANG Meng1,YU YuDe2 & YU Jun1 1 Key Laboratory of Genome Sciences and information,beijing institute of Genomics,chinese academy of Sciences,beijing 100029,china 2 institute of Semiconductors,chinese academy of Sciences,beijing 100083,china Key Laboratory of Genome Sciences and information Beijing Institute of Genomics Chinese Academy of Sciences Beijing China institute of Semiconductor Chinese Academy of Sciences Beijing China

As one of the most powerful tools in biomedical research,DNA sequencing not only has been improving its productivity at an exponential growth rate but has also been evolving into a new layout of technological territories toward engineering and physical disciplines over the past three *** this technical review,we look into technical characteristics of the next-generation sequencers and provide insights into their future development and *** envisage that some of the emerging platforms are capable of supporting the USD1000 genome and USD100 genome goals if given a few years for technical *** also suggest that scientists from china should play an active role in this campaign that will have a profound impact on both scientific research and societal healthcare systems.

关键词： genomics DNA sequencing next generation sequencing technologies sequencer

Practical Application of Participatory Approach in Land Conversion Project Planning: A Case in Quxian County, Sichuan Province

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chinese forestry Science and Technology 2003年第4期2卷 50-57页

作者： LI Weichang DENG HuafengResearch institute of forestry Policy and information. chinese academy of forestry. beijing 100091. china eiiine forestrv Universuty. Beiiine 100081. china

Application of participatory approaches in governmental forestry projects is a bran-new forestry design method. The purpose is to plan the utilization of land correctly, and to determine planting sites, planting species, participating households and management models, based on the projects' requirements and the farmers' demands. Participatory approaches are now practiced in some of the counties in Land Conversion Project. The paper presents the significance and necessity of practicing community mechanis...

关键词： participatory approaches Land Conversion Project planning

Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2,3 , ZHOU Wancun 1 ,ZHOU Jieming 4 , ZHU Mingcang 3,5 1. institute of Mountain Hazards and Environment, chinese academy of Sciences , Chengdu 610041, Sichuan, china 2. Graduate University of chinese academy of Sciences, beijing 100049, china 3. Sichuan institute of Land resource Management, Chengdu 610041, Sichuan , china 4. Department of resources and Environment Science, Sichuan Normal University , Chengdu 610061, Sichuan, china 5. College of information Engineering, Chengdu University of Technology, Chengdu 610059, Sichuan, china institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate University of chinese academy of Sciences Beijing China Sichuan institute of Land resource Management Chengdu Sichuan China Department of resources and Environment Science Sichuan Normal University Chengdu Sichuan China College of information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.