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

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Science china(Technological sciences) 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 sciences, 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.

Designing regional pattern for ecosystem restoration:A case study

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Science china(Technological sciences) 2006年第z1期49卷 86-97页

作者： LI Guoqiang , MA Keming, FU Bojie & LIU Shiling state key lab of systems ecology, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china Department of Water Environment, china Institute of Water Resources and Hydropower research, beijing 100038, china School of environmental sciences, beijing Normal University, beijing 100875, china 1. state key lab of systems ecology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China 2. Department of Water Environment China Institute of Water Resources and Hydropower Research Beijing 100038 China 3. School of environmental sciences Beijing Normal University Beijing 100875 China

Designing regional pattern is challenging for ecosystem restoration both in theory and in practice. The present study proposed a new approach to design regional pattern for ecosystem restoration with a case in the arid valley of Upper Minjiang River, SW china. The procedures are: (1) Determine the regional pattern of main environmental factors based on the relationships between the important environmental factors and the main geographical factors generated from DEM data. (2) Overlay the maps of the main environmental factors. (3) Generate a lookup table according to the species selection rule we proposed to link the candidate restoration species to the main environmental factors.(4) Determine the regional pattern of ecosystem restoration by positioning the restoration species in the map of environmental factors according to the lookup table. The regional restoration pattern designed in this way would be applicable not only to restoring a region, but also to predicting the future landscape change.

关键词： environmental factors, GIS, restoration species, Upper Minjiang River Valley.

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

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Science china(Technological sciences) 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, china School of Forestry, Northeast Forestry University, Harbin 150040, china state key lab of systems ecology, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china Graduate University of chinese academy of sciences, beijing 100039, china 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.

Towards Sustainable Urban environmental Management in Jiangyin city, East china

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chinese Journal of Population,Resources and Environment 2004年第3期2卷 50-56页

作者： Hu Dan, Wang Rusong & Yuan Shaojun Department of the key lab of systems ecology, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china Department of the key lab of systems ecology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Dramatic economic and social changes have taken place in Jiangyin city due to rapid and uneven urbanization and industrialization. The environmental degradation has followed driven by these changes since the 1980's. With the pressures and effects of environmental deterioration, the city has implemented environmental management to hold back the trends of negative environmental changes. From the viewpoint of systems, DPSER is a good model for urban environmental changes to understand the causes, pressure, state, effect, existing responses and future action strategies. We took Jiangyin city, a developed city in South Jiangsu province, East china, as an example, and analyzed the characteristics of environmental changes and urban responses using DPSER model. Some operational strategies have been put forward to direct the city environmental management towards a sustainable road step by step.

关键词： DPSER analysis model Jiangyin city in East china Sustainable environmental management Urbanization

RHEOLOGICAL BEHAVIOR OF EPOXY RESIN WATERBORNE DISPERSIONS

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chinese Journal of Polymer Science 2001年第5期19卷 471-476页

作者： Zhen-zhong Yang Yuan-ze Xu De-lu Zhao state key laboratory of Polymer Physics & Chemistry, center for Molecular Science Institute of Chemistry, chinese academy of sciences, beijing 100080 china chinese Acad Sci Inst Chem State Key Lab Polymer Phys & Chem Ctr Mol Sci Beijing 100080 Peoples R China

The waterborne dispersions of epoxy resin were prepared by the phase inversion emulsification technique. Rheological behavior and its relationship with the structural change of the systems were studied. It was shown that the concentrated dispersions were highly viscoelastic and pseudoplastic, which was attributed to the formation of a physical network among the waterborne particles via hydrogen bond. The dilute dispersions were Newtonian fluids. The discrete clusters composed of small waterborne particles were found in diluted dispersions. With increasing solid content, there existed a structural transition via percolation through a cluster-cluster aggregation mode to form the physical network, which was qualitatively evidenced by the TEM morphologies.

关键词： epoxy resin waterborne dispersion rheological behavior cluster-cluster aggregation percolation transition

Retrospect and prospect of watershed hydrological model

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Communications in Nonlinear Science and Numerical Simulation 2001年第3期6卷 172-177页

作者： B. CHEN, L. Z. XIA, Z. F. YANG and G. Q. CHEN state key laboratory for Studies of Turbulence and Complex systems / center for environmental sciences, Peking University, beijing 100871, china Institute of environmental sciences, beijing Normal Universitg, state key lab. Studs. T./C.S. Center for Environmental Sciences Peking University Beijing 100871 China Institute of environmental sciences Beijing Normal University Beijing 100875 China

A brief review is presented of the development of watershed hydrological models. Conventional Hydrological Model, Grey Hydrological Model, Digital Hydrological Model and Intelligent Hydrological Model are analyzed. The frameworks of Fuzzy Cognitive Hydrological Model and Integrated Digital Watershed Hydrological Model are presented.

关键词： watershed hydrological model digital watershed complex system

Temporal and Spatial Patterns of Throughfall under Eucommia ulmoides Forest

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Temporal and Spatial Patterns of Throughfall under Eucommia ...

Comparative Analysis of Two-component Signal Transduction System in Two Streptomycete Genomes

第三世界生态高峰会

作者： CAO Yun OUYANG Zhiyun ZHENG Hua HUANG Zhigang WANG Xiaoke MIAO Hong state key laboratory of systems ecology.research center for eco-environmental sciences,chinese academy of sciences,beijing 100085.china

As an important hydrological process in rainfall redistribution, throughfall is responsible for the transfer of rainfall from a tree canopy to the soil and clearly influences the soil and water conservation in forest *** of spatial distribution of throughfall are of significance of *** under Eucommia ulmoides forest was measured from July 2004 to September 2005 at the ecological Benefit Monitoring Station of the Yangtze River Protection Forest,which is located in Cili County,Hunan Province(29°30′N, 110°10′E).Results show that:The correlation between throughfall and rainfall was *** the whole measurement period,the volume of throughfall accounted for 71.6% of gross *** maximal volume of throughfall occurred in July 2004 and the minimal throughfall relative to rainfall occurred in November *** spatial variation in throughfall was observed below the canopy of Eucommia ulmoides ***,throughfall among different sampling sites differed significantly(P<0.05)and the CV of throughfall decreased with increasing rainfall depth and rainfall intensity. Throughfall percentage at sampling sites of 5th,8th,21st and 23nd differed significantly(P<0.05)from above 80% of total sampling sites and cluster analysis showed the tbroughfall variation among all sampling *** under the canopy had evident rainfall ***,there were throughfall percentage values above 100 in 50% of all sampling sites and 28.8% of total rainfall cases In addition,the canopy characteristics had influence on the spatial distribution of *** was a significantly negative correlation between canopy height,coverage and throughfall ***,there was a significantly positive correlation between distances from the sampling site to the nearest tree trunk,trunk angle inclination and throughfall percentage.

关键词： Throughfall Rainfall redistribution Spatial variability Temporalpattern Eucommia ulmoides forest

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Acta Biochimica et Biophysica Sinica 2007年第5期39卷 317-325页

作者： WU WEI~(1,3#), Weihua WANG~(2#), Zhiwei CAO~(3#), Hong YU~3, Xiaojing WANG~1, Jing ZHAO~3, Hao TAN~3, Hao XU~3, Weihong JIANG~(2*), and Yixue LI~(1,3*) 1 Bioinformation center, key lab of systems Biology, Shanghai Institutes for Biological sciences, chinese academy of sciences, Graduate School of the chinese academy of sciences, Shanghai 200031, china 2 laboratory of Molecular Microbiology, Institute of Plant Physiology and ecology, Shanghai Institutes for Biological sciences, chinese academy of sciences, Graduate School of the chinese academy of sciences, Shanghai 200032, china 3 Shanghai center for Bioinformation Technology, Shanghai 200235, china Bioinformationcenter KeyLabofSystemsBiologyShanghaiInstitutesforBiologicalSciencesChineseAcademyofSciencesGraduateSchooloftheChineseAcademyofSciencesShanghai200031China

Species of the genus Streptomyces are major bacteria responsible for producing most natural antibiotics. Streptomyces coelicolor A3(2) and Streptomyces avermitilis were sequenced in 2002 and 2003, respectively. Two-component signal transduction systems (TCSs), consisting of a histidine sensor kinase (SK) and a cognate response regulator (RR), form the most common mechanism of transmembrane signal transduction in prokaryotes. TCSs in S. coelicolor A3(2) have been analyzed in detail. Here, we identify and classify the SK and RR of S. avermitilis and compare the TCSs with those of S. coelicolor A3(2) by computational approaches. Phylogenetic analysis of the cognate SK-RR pairs of the two species indicated that the cognate SK-RR pairs fall into four classes according to the distribution of their orthologs in other organisms. In addition to the cognate SK-RR pairs, some potential partners of non-cognate SK-RR were found, including those of unpaired SK and orphan RR and the cross-talk between different components in either strain. Our study provides new clues for further exploration of the molecular regulation mechanism of streptomycetes with industrial importance.

关键词： Streptomyces two-component system cross-talk phylogenetic analysis

research on the SCS-CN initial abstraction ratio using rainfall-runoff event analysis in the Three Gorges Area,china

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Research on the SCS-CN initial abstraction ratio using rainf...