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The roles of a decision support system in applying forest ecosystem management in Northeast china

science china(Technological {2.) 2006年第z1期49卷 9-18页

作者： DAI Limin, ZHENG Bofu, Guofan Shao & ZHOU Li State Key Lab of Systems Ecology, research center for Eco-Environmental {2., chinese academy of sciences, Beijing 100085, china Institute of applied Ecology, chinese academy of sciences, Shenyang 110016, china Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Graduate University of chinese academy of sciences, Beijing 100101, china 1. State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China2. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China3. Department of Forestry and Natural Resources Purdue University West Lafayette IN 47907 USA4. Graduate University of Chinese Academy of Sciences Beijing 100101 China

Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in china is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR.

关键词： forest functions, forested landscapes, forest services, forest models, geographic information systems.

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Synthesis,characterization,properties and crystal structure of heterometallic 1D coordination polymers {[CuLZn·CuLZn(H_2.)]·H_2.}_n

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science china Chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, CHENG Yanxiang2.& NIU Jingyang1 1. Chemistry and Chemical Engineering College of Henan University, Kaifeng 475001, china 2. Changchun Institute of applied Chemistry,{2., Changchun 13002., china 1. Chemistry and Chemical Engineering College of Henan University Kaifeng 475001 China 2. Changchun Institute of applied Chemistry Chinese Academy of Sciences Changchun 130022 China

Copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3-carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

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Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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science china(Technological {2.) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui Institute of applied Ecology, chinese academy of sciences, Shenyang 110016,{2. School of Forestry, Northeast Forestry University, Harbin 150040,{2. State Key Lab of Systems Ecology, research center for Eco-Environmental sciences, chinese academy of sciences, Beijing 100085,{2. Graduate University of chinese academy of sciences, Beijing 100039,{2. 1. Institute of applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. School of Forestry Northeast Forestry University Harbin 150040 China 3. State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 4. Graduate University of chinese academy of sciences Beijing 100039 China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of china (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was44.2., much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

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Simulation studies of high-latitude magnetospheric boundary dynamics

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science china(Technological {2.) 2004年第4期47卷 421-435页

作者： PU Zuyin1, SHI Quanqi1,3, XIAO Chijie1, FU Suiyan1, ZHANG Hui1,2. ZONG Qiugang2.& LIU Zhenxing3 1. School of Earth and space sciences, Peking University, Beijing 100871,{2. 2. center for space Physics, Boston University, 72. Commonwealth Avenue, Boston, MA 02.15, USA 3. center for space science and Application research, chinese academy of sciences, Beijing 100080,{2. 1. School of Earth and space sciences Peking University 100871 Beijing China 2. center for space {2. and Application research Chinese Academy of Sciences 100080 Beijing China 3. center for space Physics Boston University 725 Commonwealth Avenue 02215 Boston MA USA

Magnetic reconnection at the high-latitude magnetopause is studied using 2.5-dimensional Hall-MHD simulation. Concentric flow vortices and magnetic islands appear when both Hall effect and sheared flow are considered. Plasma mixing across the magnetopause occurs in the presence of the flow vortices. Reconnected structure generated in the vicinity of the subsolar point changes its geometry with increasing flow shear while moving to high latitudes. In the presence of flow shear, with the Hall-MHD reconnection a higher reconnection rate than with the traditional MHD is obtained. The out-of-plane components of flow and magnetic field produced by the Hall current are redistributed under the action of the flow shear, which makes the plasma transport across the boundaries more complicated. The simulation results provide some help in understanding the dynamic processes at the high latitude magnetopause.

关键词： magnetopause, entry layer, magnetic reconnection, vortex reconnection, Hall effect, flow shear.

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Relative position determination of a lunar rover using high-accuracy multi-frequency same-beam VLBI

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science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 571-578页

作者： LIU QingHui1, CHEN Ming1, XIONG WeiMing2. QIAN ZhiHan1, LI JinLing1, HAO WangHong1,4, WANG GuangLi1, ZHENG WeiMin1, GUAN Di3, ZHU RenJie1, WANG WeiHua1, ZHANG XiuZhong1, JIANG DongRong1, SHU FengChun1, PING JinSong1 & HONG XiaoYu11 Shanghai Astronomical Observatory, chinese academy of sciences, Shanghai 2.0030, china 2.{2., chinese academy of sciences, Beijing 100190, china 3 Lunar Explorer Engineering General Department, chinese academy of sciences, Beijing 100012. china 4 Beijing Institute of Tracking and Telecommunications Technology, Beijing 100094, china 1. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China2. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China4. Beijing Institute of Tracking and Telecommunications Technology Beijing 100094 China3. Lunar Explorer Engineering General Department Chinese Academy of Sciences Beijing 100012 China

Multi-frequency same-beam VLBI means that two explorers with a small separation angle are simultaneously observed with the main beam of receiving antennas. In the same-beam VLBI, the differential phase delay between two explorers and two receiving telescopes can be obtained with a small error of several picoseconds. The differential phase delay, as the observable of the same-beam VLBI, gives the separation angular information of the two explorers in the celestial sphere. The two-dimensional relative position on the plane-of-sky can thus be precisely determined with an error of less than 1 m for a distance of 3.8×105 km far away from the earth, by using the differential phase delay obtained with the four chinese VLBI stations. The relative position of a lunar rover on the lunar surface can be determined with an error of 10 m by using the differential phase delay data and the range data for the lander when the lunar topography near the rover and the lander can be determined with an error of 10 m.

关键词： same-beam VLBI differential phase delay relative position determination lunar rover

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Single crystal β-Ga_2._3: Cr grown by floating zone technique and its optical properties

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science china(Technological {2.) 2007年第1期50卷 51-56页

作者： ZHANG JunGang1, 2. LI Bin3, XIA ChangTai1, XU Jun1, DENG Qun4, XU XiaoDong1, WU Feng1, XU WuSheng4, SHI HongSheng4, PEI GuangQing1, 2.& WU YongQing1,2.1 Shanghai Institute of Optics and Fine Mechanics, chinese academy of sciences, Shanghai 2.1800, china 2.Graduate School of the chinese academy of sciences, Beijing 100039, china 3 Shanghai Institute of applied Physics, chinese academy of sciences, Shanghai 2.1800, china 4 GE (china) research and Development center Co. Ltd., Shanghai 2.12.3, china 1. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China 3. Shanghai Institute of applied Physics Chinese Academy of Sciences Shanghai 201800 China 4. GE (china) research and Development {2. Co. Ltd. Shanghai 201203 China

β-Ga2.3: Cr single crystals were grown by floating zone technique. Absorption spectra and fluorescence spectra were measured at room temperature. The values of field splitting parameter Dq and Racah parameter B were obtained by the peak values of absorption spectra. The value 10Dq/B=2..14 manifests that in β-Ga2.3 crystals Cr3+ ions are influenced by low energy crystal field. After high temperature annealing in air, the Cr3+ intrinsic emission was enhanced and the green lumines-cence disappeared. The strong and broad 691 nm emission was obtained at 42. nm excitation due to the electron transition occurred from 4T2.to 4A2. The studies manifest that the β-Ga2.3 crystals have the potential application for tunable laser.

关键词： β-Ga2.3: Cr single crystals floating zone technique tunable laser spectrum.

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Propagation of interplanetary shock excited ultra low frequency (ULF) waves in magnetosphere-ionosphere-atmosphere——Multi-spacecraft “Cluster” and ground-based magnetometer observations

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science china(Technological {2.) 2010年第9期53卷 2528-2534页

作者： WANG ChengRui1,2.ZONG QiuGang1,3 & WANG YongFu1 1 Institute of space Physics and applied Technology,Peking University,Beijing 100871,{2. 2.Sate Key Laboratory of space Weather,chinese academy of sciences,Beijing 100190,{2. 3 center for Atmospheric research,600 Suffolk Street,University of Massachusetts Lowell,MA 01854,USA 1. Institute of space Physics and applied Technology Peking University Beijing 100871 China2. Sate Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China3. Center for Atmospheric Research University of Massachusetts 600 Suffolk Street Lowell MA 01854 USA

The ultra low frequency (ULF) wave in magnetosphere can act as an important means for solar wind energy inward *** paper quantitatively analyzes the propagation process of the ULF wave triggered by the interplanetary shock propagating from inner magnetosphere equatorial plane along magnetic field lines to the top of the ionosphere and below ionosphere propagating process and establishes a relatively complete magnetosphere-ionosphere-atmosphere propagation model which can be used to study the relationship between the amplitude of the ULF waves triggered by the interplanetary shock wave in magnetospheric space and the magnetic effect caused by the ULF *** a comparison with recent observations,we found that: in the event during November 7,2.04 that an interplanetary shock wave interacted with the magnetosphere,Cluster satellites observed that electric field fluctuations and the band-pass filtered result of ground stations meridional component had similar *** with the geomagnetic measurement near the footprints,we found that the electric field disturbance in the magnetosphere spread along the ground magnetic field lines in the form of the ULF waves and changed into geomagnetic *** result reveals that the ULF wave is in contact with the ground geomagnetic *** ULF waves couple with ionized components in ionosphere and spread to the ground in the form of electromagnetic *** this research,we believe that the magnetosphere,ionosphere and ground magnetic effects caused by interplanetary shock wave are the same physical phenomena responding in different *** on the overall consideration of entire electromagnetic response to the interplanetary shock wave,we found that the correlation between CLUSTER multi-satellite observation and geomagnetic station observation is due to the ULF wave propagated in magnetosphere-ionosphere-atmosphere system,and we quantitatively interpreted this response process

关键词： ultra low frequency (ULF) wave magnetic storm ionosphere IRI model interplanetary shock

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Ecological hydrograph based on Schizothorax chongi habitat conservation in the dewatered river channel between Jinping cascaded dams

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science china(Technological {2.) 2011年第S1期54卷 54-63页

作者： LI RuoNan 1,CHEN QiuWen 1,2.& Duan Chen 1,3 1 research center for Eco-environmental {2.,chinese academy of sciences,Beijing 100085,china 2.7} Three Gorges University,Yichang 443002.china 3 Hydraulics Department,Changjiang River Scientific research Institute,Wuhan 430010,china 1. research center for Eco-environmental {2. Chinese Academy of Sciences Beijing 100085 China 2. china Three Gorges University Yichang 443002 China 3. Hydraulics Department Changjiang River Scientific Research Institute Wuhan 430010 China

Hydropower development changes the river hydrological regime,thereby altering river ecosystem *** important measure for reducing degradation of ecosystem is to determine ecological flow and implement it by reservoir *** paper described a method to calculate river ecological flow based on fish habitat conservation and applied it to Jinping River Bend of Yalong *** chongi was selected as target species,and the fish habitat model coupling with water environmental model was developed according to the relationship between fish and water environment ***,improved hydraulic habitat suitability index(IHHS) and habitat fragment index(HFI) varying with discharge were discussed in this *** area representing average annual flow was taken as a reference,and then ecological hydrographs under different habitat conservation levels were calculated considering season variation and life stages of *** to the natural condition,the model results indicated that the reservoir operation clearly influenced the habitat of the target *** was proposed to ensure flow releases to maintain 70%-90% habitat in section after joint while about 60% before joint.

关键词： river habitat habitat assessment ecological flow ecological hydrograph

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Ecological Behavior of Linear Alkylbenzene Sulfonate (LAS) in Soil-Plant Systems

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Pedosphere 2005年第2期15卷 216-224页

作者： JIALiang-Qing OUZi-Qing OUYANGZhi-Yun researchcenterforEco-Environmental{2. ChineseAcademyofSciencesBeijing100085（China）／／AnhuiAcademyofEnvironmentalSciencesHefei230061（China） InstituteofappliedEcology ChineseAcademyofSciencesShenyang100016（China） researchcenterforEco-Environmental{2. ChineseAcademyofSciencesBeijing100085（China）

More and more linear alkylbenzene sulfonate (LAS) has contaminated the water and soil ma pollution discharge, making it important to identify the ecological behavior and toxicity of LAS so as to carry out measures that will reduce its negative effects on the ecosystem. The ecological behavior of LAS. including degradation, migration, and plant uptake, in both soil-paddy rice and soil-soybean systems was studied. Reduction of LAS in pot and field plots followed the first order reaction kinetics with degradation half-lives of 35-50 days with LAS decreasing to very low concentrations after a season of crop growth. Strong migration ability for LAS was found and the breakthrough time in a 1.5 in soil monolith was significantly shortened to 2. days by preferential flow. Leachate volumes of soil-paddy and soil-soybean systems at preferential breakthrough were much different, while the leachate volumes at equilibrium governed by soil adsorption/desorption processes were very similar. Significant uptake of LAS in both paddy rice and sovbeans was observed in pot and field experiments (P 2. μg mL-1 and above of LAS significantly inhibited the growth of paddy seedlings (P < 0.05). The critical concentration for LAS in soil inhibiting the growth and yield of paddy was 160 μg g-1; when higher, there was a strong negative influence, with decreases in height, spike length, and production, when lower than 80 μg g-1, paddy growth was stimulated. There was little effect of LAS on soybeans.

关键词： degradation ecological behavior linear alkylbenzene sulfonate migration preferential flow

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Bifurcations and Chaos in a Discrete Predator-prey System with Holling Type-IV Functional Response

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Acta Mathematicae Applicatae Sinica 2005年第1期21卷 157-176页

作者： Ji-cai Huang Department of applied Mathematics, College of science,{2. Agriculture University academy of Mathematics and Systems science, chinese academy of sciences, Beijing 100080,{2. Department of applied Mathematics College of Science China Agriculture University academy of Mathematics and Systems science Chinese Academy of Sciences Beijing 100080 China

A discrete predator-prey system with Holling type-IV functional responseobtained by the Euler method is first investigated. The conditions of existence for foldbifurcation, flip bifurcation and Hopf bifurcation are derived by using the center manifold theoremand bifurcation theory. Furthermore, we give the condition for the occurrence of codimension-twobifurcation called the Bogdanov-Takens bifurcation for fixed points and present approximateexpressions for saddle-node, Hopf and homoclinic bifurcation sets near the Bogdanov-Takensbifurcation point. We also show the existence of degenerated fixed point with codimension three atleast. The numerical simulations, including bifurcation diagrams, phase portraits, and computationof maximum Lyapunov exponents, not only show the consistence with the theoretical analysis but alsoexhibit the rich and complex dynamical behaviors such as the attracting invariant circle,period-doubling bifurcation from period-2.3,4 orbits, interior crisis, intermittency mechanic, andsudden disappearance of chaotic dynamic.

关键词： predator-prey system bifurcations Bogdanov-Takens bifurcation chaos

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