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Digital forestry research in china

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science china(Technological {2.) 2006年第z1期49卷 1-8页

作者： TANG Shouzheng, TANG Una, Guofan Shao & DAI Limin Research institute of Resource Information Techniques, chinese {2. of Forestry, beijing 100091, china institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, china Departmet of Forestry and natural resources, Purdue University, West Lafayette, IN 47907, USA Graduate University, chinese academy of sciences, beijing 100101, china Research institute of Resource Information Techniques Chinese Academy of Forestry Beijing 100091 China institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Department of Forestry natural resources Purdue University West Lafayette IN 47907 USA Graduate University Chinese Academy of Sciences Beijing 100101 China

Digital Forestry as a concept was developed after the Digital Earth program. The chinese scientists were not only among the pioneers who first proposed the concept of Digital Forestry, but also contributed a lot to the development of Digital Forestry. Digital Forestry is a digital framework to maintain forest planting, management, using, and protect. The synergetic use of computationally-intensive quantitative methods together with information technologies is the most important foundation for the development of Digital Forestry. Under this situation, the experience of Digital Forestry development in china is relatively rich. A number of academicians, scholars, and professional administrators were involved in discussing the Digital Forestry Construction Scheme. The Project of Digital Forestry Practicability approved by the State Forestry Administration is a major instance in developing Digital Forestry standard and key techniques. By introducing a case study of Digital Forestry, this paper reviews the concept of Digital Forestry, the way turning traditional forestry into Digital Forestry, and the future development of Digital Forestry.

关键词： Digital Forest, Digital Earth, Digital Forestry standard, Digital Forestry techniques.

DESIGN OF FARMLAND GIS FOR PRECISION AGRICULTURE

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chinese geographical {2. 2003年第1期13卷 20-24页

作者： AN Kai, XIE Gao-di, LENG Yun-fa, XIAO Yu (institute of geographical {2. and natural resources Research, the chinese academy of sciences, beijing 100101, P. R. china) institute of geographical {2. and natural resources Research the Chinese Academy of Sciences Beijing 100101 P. R. China

Precision Agriculture, also known as Precision Farming, or Prescription Farming, is a modern agriculture technology system, which brings ' precision' into agriculture system. All concepts of Precision Agriculture are established on the collection and management of variable cropland information. As the tool of collecting, managing and analyzing spatial data, GIS is the key technology of integrated Precision Agriculture system. This article puts forward the concept of Farmland GIS and designs Farmland GIS into five modules, and specifies the functions of the each module, which builds the foundation for practical development of the software. The study and development of Farmland GIS will propel the spreading of Precision Agriculture technology in china.

关键词： precision agriculture farmland GIS site-specific crop management prescription map

On coordinated development of oasis and environment in arid area

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Journal of geographical sciences 2001年第1期11卷 117-121页

作者： FU Xiao-feng, LI Zhe (institute of geographic {2. and natural resources Research, CAS, beijing 100101, china) institute of geographic {2. and natural resources Research CAS

Based upon the formation and evolution of oasis and the factors restricting the coordinated development of oasis economy and environment, this paper presents a goal of the development in coordination. It suggests that the sustainable survival and development of oasis could be ensured only if the oasis-desert and water source ecology are managed in a combined way to form a macro system. In light with the above mentioned, the approach to the development of economy and environment of oasis in arid area should depend upon the establishment of an oasis ecological and economic system, which suits the arid environment and promotes the efficiency of resource configuration, stabilizes economic increment and benefits ecological development.

关键词： oasis development environment arid area

The retrieval of two-dimensional distribution of the earth's surface aerodynamic roughness using SAR image and TM thermal infrared image

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science china Earth {2. 2004年第12期47卷 1134-1146页

作者： ZHANG Renhua 1 ,WANG Jinfeng 1 ,ZHU Caiying 1,2.,SUN Xiaomin 1 & ZHU Zhilin 1 1.institute of geographical {2. and natural resources,chinese academy of {2.,beijing 100101,china 2.institute of Surveying and Mapping,Information Engineering University of the chinese People’s Liberation Army,Zhengzhou 450052.china 1. chinese academy of sciences Institute of Geographical Sciences and Natural Resources 100101 Beijing China 2. Information Engineering University of the chinese People’s Liberation Army Institute of Surveying and Mapping 450052 Zhengzhou China

After having analyzed the requirement on the aerodynamic earth’s surface rough- ness in two-dimensional distribution in the research field of interaction between land surface and atmosphere, this paper presents a new way to calculate the aerodynamic roughness using the earth’s surface geometric roughness retrieved from SAR (Synthetic Aperture Radar) and TM thermal infrared image data. On the one hand, the SPM (Small Perturbation Model) was used as a theoretical SAR backscattering model to describe the relationship between the SAR back- scattering coefficient and the earth’s surface geometric roughness and its dielectric constant re- trieved from the physical model between the soil thermal inertia and the soil surface moisture with the simultaneous TM thermal infrared image data and the ground microclimate data. On the basis of the SAR image matching with the TM image, the non-volume scattering surface geo- metric information was obtained from the SPM model at the TM image pixel scale, and the ground pixel surface’s equivalent geometric roughness—height standard RMS (Root Mean Square) was achieved from the geometric information by the transformation of the typical to- pographic factors. The vegetation (wheat, tree) height retrieved from spectrum model was also transferred into its equivalent geometric roughness. A completely two-dimensional distribution map of the equivalent geometric roughness over the experimental area was produced by the data mosaic technique. On the other hand, according to the atmospheric eddy currents theory, the aerodynamic surface roughness was iterated out with the atmosphere stability correction method using the wind and the temperature profiles data measured at several typical fields such as bare soil field and vegetation field. After having analyzed the effect of surface equivalent geo- metric roughness together with dynamic and thermodynamic factors on the aerodynamic surface roughness within the working area, this paper first establishe

关键词： surface geometric roughness, aerodynamic surface roughness, SAR backscattering model, moisture retrieval model, roughness transformation model.

“Greatest lake period” and its palaeo-environment on the Tibetan Plateau

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Journal of geographical sciences 2001年第1期11卷 34-42页

作者： LI Bing-yuan, ZHU Li-ping (institute of geographic {2. and natural resources Research, CAS, beijing 100101, china) institute of geographic {2. and natural resources Research CAS Beijing China

The “greatest lake period” means that the lakes are in the stage of their maximum areas. As the paleo lake shorelines are widely distributed in the lake basins on the Tibetan Plateau, the lake areas during the “greatest lake period” may be inferred by the last highest lake shorelines. They are several, even tens times larger than that at present. According to the analyses of tens of lakes on the Plateau, most dating data fell into the range of 40-2. ka BP, some lasted to 2. ka BP. It was corresponded to the stage 3 of marine isotope and interstitial of last glaciation. The occurrence of maximum areas of lakes marked the very humid period on the Plateau and was also related to the stronger summer monsoon during that period.

关键词： Tibetan Plateau greatest lake period highest lake levels interstitial of last glaciation paleo-monsoon

Astronomical function and date of the Taosi observatory

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science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 151-158页

作者： WU JiaBi1, CHEN MeiDong2.& LIU CiYuan3 1 National Astronomical Observatories, chinese academy of sciences, beijing 100012.{2. 2.institute for the History of natural science, chinese academy of sciences, beijing 100010,{2. 3 National Time Service Center, chinese academy of sciences, Xi’an 710600,{2. 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China 2. institute for the History of natural {2. Chinese Academy of Sciences Beijing 100010 China 3. National Time Service Center Chinese Academy of Sciences Xi’an 710600 China

The Taosi site in Xiangfen County,Shanxi Province,may be the capital of the King Yao. Archeologists recently discovered a large semi-circular stamped-earth platform, II FJT1,which has a clear and definite pounded-earth central core together with a curved wall perforated by twelve gaps. The platform is said to be an ancient observatory used to determine the seasons by watching the sunrise. Each feature of II FJT1 was precisely measured and the data are reproduced in this paper. An astronomical analysis of slots E2.and E12.was carried out using the azimuths of the slots' centerlines and the vertical angle of the mountain ridge opposite, above which the sun rises. The results show that at present the sun is close to the two slots but does not exactly enter them at summer and winter solstice sunrise. Using 14C analysis archeologists dated the site to about 2.00 BC. Because of the secular change in the obliquity of the ecliptic,at that date on the summer solstice the half-risen sun would have appeared inside slot E12.just to the right of the centerline,and on the winter solstice the sun would have been exactly on the centerline of slot E2. This result provides compelling proof that II FJT1 is an ancient observatory.

关键词： astro-archeology astro-chronology Taosi culture ancient observatory time service

Response synchronization: New progress in brain-visual information processing

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chinese science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry , institute of Atmospheric Physics , chinese academy of sciences , {2. 10002., china 2. Commission of the National natural science Foundation of china , {2. 100083, china 3. The Center of Information science , Peking University, {2. 100871, china 4. Open Laboratory of Visual Information Processing , institute of Biophysics , chinese academy of sciences , beijing 100101, china State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National natural science Foundation of{2. Beijing China The Center of Information science Peking University Beijing China Open Laboratory of Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

Value of ecosystem services in china

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chinese science Bulletin 2000年第10期45卷 870-876页

作者： CHEN Zhongxin & ZHANG XinshiLaboratory of Quantitative Vegetation Ecology, institute of Botany, chinese academy of sciences, {2. 100093, china Current address: institute of natural resources and Regional Planning, chinese academy of Agricultural sciences, {2. 100081, china Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing China

The function and services are the important components of the life-support system in theplanet, as well as the basic elements for sustainable development of environment and society. It is a must to evaluate it for incorporating it with the social-economic system. It is also an important approach to draw the public attention on the environmental and ecosystem conservation. In this study, the ecosystem function and services in china were estimated by employing the classification and economic parameters from Costanza et al. The type and area of terrestrial ecosystems were extracted from Vegetation Map of china (1:4 000 000), and then the distribution map of ecosystem services of china was drawn. According to our calculation, the total value of ecosystem services in china is 77 834.48×108 RMB yuan per annum. The value for terrestrial ecosystem is 56 098.46×108 yuan per annum, and that for marine ecosystem is 2. 736.02.108 yuan per annum. The value of ecosystem services in china is 1.73 times bigger

关键词： ecosystem function service.

Ecological hydraulic radius model to calculate instream flow requirements for transporting sediment in the western water transfer region

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science china(Technological {2.) 2009年第11期52卷 3401-3405页

作者： MEN BaoHui1 & LIU ChangMing2.1 Renewable Energy institute, North china Electric Power University, {2. 102.06, china 2.Key Laboratory of Water Cycle and Related Land Surface Process, institute of geographical sciences and natural resources Research, chinese academy of sciences, beijing 100101, china 1. Renewable Energy institute North China Electric Power University Beijing 102206 China 2. Key Laboratory of Water Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Transporting sediment is a natural function of the river. To maintain the normal evolution of the river certain amount of water flow is required, which is called the instream flow requirements for transporting sediment (IFRTS). We defined the permitting flow velocity by the conception of IFRTS, and also put forward the ecological hydraulic radius model (EHRM) to estimate IFRTS. The calculating process of EHRM is explained by the example of Daofu Hydrological Station on Xianshui branch of Yalong River in the west line first-stage construction of South-North Water Transfer Project. The result shows that the IFRTS occupied 2..7%―59.5% of annual mean discharge in flood season, the average of IFRTS was about 100.2.m3/s during 1966―1987, it is close to the IFRTS 90 m3/s calculated by IFRTS conception. Hence, it is feasible to use EHRM to calculate IFRTS.

关键词： ecological hydraulic radius model (EHRM) instream flow requirements for transporting sediment (IFRTS) permitting flow velocity ecological hydraulic radius for transporting sediment