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Digitally determining forest inventory units with an ecological classification system

Science china(Technological sciences) 2006年第z1期49卷 118-127页

作者： TANG Una, WANG Qingli, Guofan Shao, DAI Limin, WANG Shunzhong, LI Xiufen & XU Dong institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, china Graduate University of chinese academy of sciences, beijing 100101, china Department of Forestry and natural resources, Purdue University, West Lafayette, IN 47907, USA 1. institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. Graduate University of chinese academy of sciences Beijing 100101 China 3. Department of Forestry and natural resources Purdue University West Lafayette IN 47907 USA

Management-level forest resource data in china were obtained with a combination of two forest inventories. However, inconsistencies in the spatial attributes of forest data vary between the two inventory types and between two inventories of the same type. The inconsistencies make it inconvenient for long-term forest management planning with digital technologies. Ecological Land Types (ELTs) and Ecological Land Type Phases (ELTPs) have been mapped in selected forestry regions in northeast china, where important forest industries are located. The boundaries of ELTs are determined by geomorphic conditions, which are quantified by Digital Elevation Models (DEM); ELTPs are classified by overlaying ELTs with forest vegetation data layers that are obtained with both remotely sensed and ground data. The ELTPs represent the divisions of land in terms of both natural and human-induced forest conditions, and therefore they are reliable units for forest inventories and management. This paper introduces a case study for digitally determining forest inventory units in Benxi City, Liaoning Province, northeast china. The general objective of the study was to explain how a compatible forest inventory system should be designed and why the compatible forest inventory system was significant to digital forestry in china.

关键词： forest inventory, ecological classification, ELT mapping, ELTP mapping, geographic information systems, forest management.

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GIS and ANN model for landslide susceptibility mapping

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Journal of geographical sciences 2001年第3期11卷 374-381页

作者： XU Zeng-wang (State Key Laboratory of resources and Environment Information System, institute of geographic sciences and natural resources research, CAS, beijing 100101, china) State Key Laboratory of resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research CAS

Landslide hazard is as the probability of occurrence of a potentially damaging landslide phenomenon within specified period of time and within a given area. The susceptibility map provides the relative spatial probability of landslides occurrence. A study is presented of the application of GIS and artificial neural network model to landslide susceptibility mapping, with particular reference to landslides on natural terrain in this paper. The method has been applied to Lantau Island, the largest outlying island within the territory of Hong Kong. A three-level neural network model was constructed and trained by the back-propagate algorithm in the geographical database of the study area. The data in the database includes digital elevation modal and its derivatives, landslides distribution and their attributes, superficial geological maps, vegetation cover, the raingauges distribution and their 14.years 5.minute observation. Based on field inspection and analysis of correlation between terrain variables and landslides frequency, lithology, vegetation cover, slope gradient, slope aspect, slope curvature, elevation, the characteristic value, the rainstorms corresponding to the landslide, and distance to drainage Une are considered to be related to landslide susceptibility in this study. The artificial neural network is then coupled with the ArcView3.2 GIS software to produce the landslide susceptibility map, which classifies the susceptibility into three levels: low, moderate, and high. The results from this study indicate that GIS coupled with artificial neural network model is a flexible and powerful approach to identify the spatial probability of hazards.

关键词： GIS artificial neural network model landslide susceptibility mapping

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Material component to non-linear relation between sediment yield and drainage network development:an flume experimental study

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Journal of geographical sciences 2001年第3期11卷 271-281页

作者： JIN De-sheng, CHEN Hao, GUO Qing-wu (institute of geographic sciences and natural resources {5., CAS, beijing 100101, china) institute of geographic sciences and natural resources {5.

This paper examines the experimental study on influence of material component to non-linear relation between sediment yield and drainage network development completed in the Lab. The area of flume drainage system is 81.2 m2, the longitudinal gradient and cross section slope are from 0.0348 to 0.0775.and from 0.0115.to 0.038, respectively. Different model materials with a medium diameter of 0.021 mm, 0.076 mm and 0.066 mm cover three experiments each. An artificial rainfall equipment is a sprinkler-system composed of 7 downward nozzles, distributed by hexagon type and a given rainfall intensity is 35.5. mm/***2. Three experiments are designed by process-response principle at the beginning the ψ shaped small network is dug in the flume. Running time spans are 720 m, 14.0 minutes and 5.0 minutes for Runs I, IV and VI, respectively. Three experiments show that the sediment yield processes are characterized by delaying with a vibration. During network development the energy of a drainage system is dissipated by two ways, of which one is increasing the number of channels (rill and gully), and the other one is enlarging the channel length. The fractal dimension of a drainage network is exactly an index of energy dissipation of a drainage morphological system. Change of this index with time is an unsymmetrical concave curve. Comparison of three experiments explains that the vibration and the delaying ratio of sediment yield processes increase with material coarsening, while the number of channel decreases. The length of channel enlarges with material fining. There exists non-linear relationship between fractal dimension and sediment yield with an unsymmetrical hyperbolic curve. The absolute value of delaying ratio of the curve reduces with time running and material fining. It is characterized by substitution of situation to time.

关键词： material component network sediment yield nonlinear relation experiment

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An integrated approach to scaling issues in environmental change study

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Journal of geographical sciences 2000年第4期10卷 45-52页

作者： LIU Hong-hui, YANG Xiao-huan, WANG Nai-bin, LIU Hai-yan (Center for resources and Environmental Data, institute of geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, china)

Global change research and sustainable development need to be addressed at larger scales in the light of small scale process studies. Much remains to be done before the small scale, process level understanding of ecosystem responses to global change can be reliably translated to larger scales. The paper reviews the status of scaling issues and tries to find how to extrapolate our observations and our findings at site scale up to regional scale and provide ecological information and interpretations at the regional scale. An integrated approach to scaling-up from site to region is proposed combining hierarchical theory, landscape ecology, remote sensing, geographical information system (GIS) with process/mechanistic modeling. Remote sensing and GIS will play key roles in spatial analysis, integration as well as cross scale modeling.

关键词： scale issue global change study scaling up integrated approach

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Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science china Earth sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2, KANG Shichang2,3,5. SUN Junying4,5. Paul A. Mayewski2 & QIN Dahe5.1. National Climate Center, china Meteorological Administration, beijing 100081, china 2. Climate Change institute, University of Maine, Orono, ME 04469, USA 3. institute of Tibetan Plateau {5., chinese academy of sciences, beijing 100085. china 4. chinese academy of Meteorological sciences, beijing 100081, china 5. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Environmental and Engineering {5. institute, chinese academy of sciences, Lanzhou 730000, china 1. National Climate Center China Meteorological Administration 100081 Beijing China 2. Climate Change institute University of Maine 04469 Orono ME USA 3. institute of Tibetan Plateau research Chinese Academy of Sciences 100085 Beijing China 4. Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 5. chinese academy of Meteorological sciences 100081 Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

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Quantifying soil erosion with GIS-based RUSLE under different forest management options in Jianchang Forest Farm

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中国科学：技术科学英文版 2006年第z1期49卷 160-166页

作者： ZHANG Hengming, WANG Qingli, DAI Limin, Guofan Shao, TANG Una, WANG Shunzhong & GU Huiyan institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, china Graduate University of chinese academy of sciences, beijing 100101, china Department of Forestry and natural resources, Purdue University, Lafayette IN47901, USA Northeast Forestry University, Harbin 15.040, china institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate University of chinese academy of sciences Beijing 100101 China Department of Forestry natural resources Purdue University Lafayette IN 47901 USA Northeast Forestry University Harbin 150040 China

Quantitatively estimating soil erosion with an integration of geographic information system (GIS) and the revised universal soil loss equation (RUSLE) under four different exposed soil proportion scenarios caused by forest management practices was studied at Jianchang Forest Farm. The GIS provided means of input data generation required by RUSLE model and allowed a spatial assessment of the erosion hazard over the study area. Four exposed soil proportion scenarios of 5., 10%, 20% and 30% were tested with the GIS-based RUSLE model to evaluate soil erosion hazard. The predicted soil erosion potentials were classified into five categories in order to provide valuable aids for management planning.

关键词： geographic information system, RUSLE, soil erosion, forest management.

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Analysis and Modeling on the Spatial Structure of Urban Land Use: A Case of Jinan, china

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chinese Journal of Population,resources and Environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1, 3, Zhang Zulu2, Jiang Luguang 1 1. institute of geographical sciences and natural resources {5., chinese academy of sciences, beijing 100101, china 2. College of Population, resources and Environment, Shandong Normal University, Jinan Shandong 25.014. china 3. Graduate School of the chinese academy of sciences, beijing 100039, china institute of geographical sciences and natural resources {5. Chinese Academy of Sciences Beijing 100101 China Graduate School of the chinese academy of sciences Beijing 100039 China College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1986 and 2004, the spatial structure of Jinan is studied in this paper with the method of geographic Information System (GIS). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 5.%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1986 to 2004, great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure Jinan

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Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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chinese Science Bulletin 2012年第35期57卷 4617-4626页

作者： ZHANG Ran 1,JIANG DaBang 1,2,3,LIU XiaoDong 4 & TIAN ZhiPing 2,5.1 Climate Change research Center,chinese academy of sciences,beijing 100029,{5. 2 Nansen-Zhu International research Centre,institute of Atmospheric Physics,chinese academy of sciences,beijing 100029,{5. 3 Key Laboratory of Regional Climate-Environment research for Temperate East Asia,chinese academy of sciences,beijing 100029,{5. 4 State Key Laboratory of Loess and Quaternary Geology,institute of Earth Environment,chinese academy of sciences,Xi’an 710075.{5. 5.Graduate University of chinese academy of sciences,beijing 100049,{5. 1. Climate Change research Center Chinese Academy of Sciences Beijing 100029 China 2. Nansen-Zhu International research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Key Laboratory of Regional Climate-Environment research for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China 4. State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 5. Graduate University of chinese academy of sciences Beijing 100049 China

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National Center for Atmospheric research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模

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Urban land expansion and arable land loss of the major cities in china in the 1990s

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Science china Earth sciences 2005年第9期 166-174页

作者： TAN Minghong, LI Xiubin & LU Changhe institute of geographic sciences and natural resources {5., chinese academy of sciences, beijing 100101, china

Based on the land-use data in 1990 and 2000, determined by interpreting Landsat Thematic Mapper (TM) imagery, this paper defines the extent of urban construction land, and extracts patches of urban construction land of 14. cities with the largest areas in 1990 and arable land patches around these cities. With these data, this paper analyzes the characteristics of ur- ban construction land expansion and the consequent arable land loss in East, Middle and West china, and further identifies the social, economic and spatial factors of the urban land use changes, using GIS (geographical Information System) and multivariate regression approaches. The results show that total urban land of the 14. cities expanded by 39.8%, with about 70% of the new urban land converted from arable land in the 1990s. The urban land expansion varied among the three regions, with a value of 43.0% in the East, 33.1% in the West (33.1%) and 17.8% in the Middle. Moreover, mean urban construction land per capita increased by10.7% in the East, but it decreased by 7.7% in the Middle, 1.4% in the West. Statistical analysis indicated that total wages of staff and workers could best explain the differences of urban land expansion.

关键词： china urban construction land expansion arable land loss regional difference neighboring index [I(i)].

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Relationship Between Soil Properties and Different Fractions of Soil Hg

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Pedosphere 2001年第3期11卷 257-262页

作者： WU HONGTAO YU GUIFEN QING CHANGLE and CHEN TONGBIN Southwest Agricultural University, Chongqing 400716 (china) institute of geographic sciences and natural {5., the chinese academy of sciences, beijing 100101 (china) institute of Soil Science, th 西南农业大学重庆 400716 中科院南京土壤所江苏南京 210008 中科院地理科学与资源所北京 100101

Correlation and path analysis methods were used to study the relationship between soil properties and the distribution of different soil Hg fractions with nine representative soils from Chongqing, china. Results showed that clay (5.21, respectively. The positive effect of OM and negative effect of BSP on organic Hg were the most significant, with the direct path coefficients being 0.7614.and -0.85.7, respectively. The indirect effect of clay (< 2 μm) via BSP (path coefficient = 0.4186) was the highest, showing that the real influencing factor in the effect of clay (< 2 μm) on acid-soluble organic Hg was BSP. Since the available Hg fraction, water-soluble Hg, was positively affected by soil clay content, and the quite immobile and not bioavailable residual Hg by soil BSP, suitable reduction of clay content and increase of BSP would be of much help to reduce the Hg availability and Hg activity in Hg-contaminated soils.

关键词： different fractions soil Hg soil properties

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