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Science China Earth sciences 2005年第9期48卷 1501-1509页

作者： CHEN Junfeng1,2. LI Xiubin2.& ZHANG Ming2.1. institute of Remote Sensing & GIS, Peking University, {1. 100871, China 2. institute of geographical sciences and Natural resources Research, Chinese Academy of sciences, {1. 1.01.1. China 1. institute of Remote Sensing & GIS Peking University 100871 Beijing China 2. {1. of {1. {2. and Natural resources Research Chinese Academy of Sciences 100101 Beijing Chin

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1.70, 1.86 and 1.99 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%―80%, while that of land cover changes only 2.%.

关键词： climate variation, land-cover changes, Suomo Basin, CHARM model, SWAT model.

Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, China

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Science China Earth sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1. LIANG Tao1.& TAO Shu2.1. {1. of {1. {2. and Natural resources Research, Chinese Academy of {2., beijing 1.01.1. China 2. Laboratory for Earth Surface Processes, Peking University, beijing 1.0871. China 1. institute of {1. {2. and Natural resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1.5{1.{1.03 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1.5{1.1.83, the average input and output amount of HCHs through agricultural application and degradation are 1.0 t and 1.0 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1. 1. t?a?1.and 1. t?a?1. which account for 9{1. of total transfer fluxes of HCHs isomers. There were approximately {1.3t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1.84 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1.83, and this percentage may descend to 0.5% after {1. years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science China(Technological sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1.& LIU Changming1. 2.1. School of Environmental {1., {1. Normal University, {1. 1.0875, China 2. institute of Geographic Science and Natural resources Research, {1. 1.01.1. China beijing Normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1.82.1.98, soil moisture of all layers of soil-profile (0—1.m) in the Yellow River basin over the 1. years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1.82.to 1.88 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 1. years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

Aridity/humidity status of land surface in China during the last three decades

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Science China Earth sciences 2005年第9期48卷 1510-1518页

作者： WU Shaohong1. YIN Yunhe1.2. ZHENG Du1.& YANG Qinye1.1. {1. of {1. {2. and Natural resources Research, Chinese Academy of {2. (CAS), beijing 1.01.1. China 2. Graduate School of the CAS, beijing 1.0039, China 1. institute of {1. {2. and Natural resources Research Chinese Academy of Sciences (CAS) 100101 Beijing China 2. Graduate School of the CAS 100039 Beijing China

To clarify aridity/humidity status of land surface is helpful for studying environmental background and regional differences, seeking causes of environmental change, and providing a scientific basis for researches on climate change in the future. In this paper, the authors calcu- lated potential evapotranspiration of China using data from 61. meteorological stations during the period of 1.71.2.00 with the Penman-Monteith model recommanded by FAO in 1.98. Vy- sothkii’s model was used to calculate aridity/humidity index. Then the calculated results of sta- tions were interpolated to land surface using ArcGIS. Results show that the annual average po- tential evapotranspiration is 400―1.00 mm in the whole country, 600―800 mm in most parts of it; and 350―1.00 mm in growing season (April―Octobor), which is nearly 2.0 mm less than the annual average. According to the aridity/humidity indexes of 1.0, 1.5 and 4.0, the aridity/humidity status is categorized to four types, namely, humid, subhumid, semiarid and arid. A majority of stations (76%) are more humid in growing season than the annual average. Results of com- prisons between the distribution map of aridity/humidity index with that of precipitation and vegetation indicate a good consistence of aridity/humidity status with natural environment. Therefore potential evapotranspiration calculated with modified FAO’s Penman-Monteith model in combination with aridity/humidity index that considers water balance can more reasonably explain the actual land surface aridity/humidity status of China.

关键词： potential evapotranspiration, aridity/humidity status, land surface, regional differences, Penman-Monteith.

Floating Population Increase and Its Influence on the Urban Population Situation:A Case Study in beijing

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Chinese Journal of Population,resources and Environment 2005年第1期3卷 27-35页

作者： Wu Peilin 1,2.& Lu Qi 2.1. Shandong University of Technology, Zibo Shandong 2.5049, China 2. institute of {1. {2. and Natural resources Research, Chinese Academy of {2., beijing 1.01.1. China Shandong University of Technology Zibo Shandong 255049 China institute of {1. {2. and Natural resources Research Chinese Academy of Sciences Beijing 100101 China

Floating population is a special population group in China resulting from the implementation of household registration system. This paper uses a set of floating population survey data, population censuses data and statistical data to analyze the increase and influence of floating population on the urban population situations in beijing. It is found that beijing has experienced a rapid increase of floating population since the 1.90s and that the increase of this group has become the key factor of the current population expansion in the city. Its distribution in the urban regions intensified and extended the suburbanization process of the capital. In addition, the population structures of sex, age, education and employment in beijing have changed to some extent due to the influx of floating population.

关键词： Floating population Household registration system (Hukou) Population expansion Suburbanization Population structure beijing

N_2. emissions from agricultural soils in the North China Plain: the effect of chemical nitrogen fertilizer and organic manure

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Journal of Environmental sciences 2000年第4期12卷 463-468页

作者： DONG Yun\|she 1.2.3 , Dieter Scharffe 2. Manfred Domroes 3, QI Yu chun 1. ZHANG Shen 1.(1. institute of Geographic {1. and Natural {2. Research, Chinese Academy of {1., beijing 1.01.1. China E\|mail: dongys@*** 2. M 中科院地理科学与资源所北京 1 0 0 1 0 Max- Planck-institute of Chemistry 德国 Mainz 550 2 0 Mainz University 德国 Mainz 550 99

An enclosed chamber technique was used to measure N 2. emissions from intensively agricultural soils of the North China Plain during the periods of 1.95—1.96 and 1.97—1.98, to reflect distinct components of winter wheat and summer maize growing seasons. The results showed that the continuous application of fertilizer in agricultural soils increased N\-2. emissions by a factor of 2..1.2..1. the calculated annual chemical N fertilizer\|transformed N\-2.\|N emissions was 0.67%. Our results indicated that the application of organic manure also had a significant influence on soil N 2. emissions, which combined with the use of chemical N increased about 2.% in a year. It was calculated that there were about 0.1.% N of organic manure transformed as N 2. N. Annual mean N 2. emission from our study area of fertilized soils was estimated to be 57.1.μgN 2./(m 2.h). A weak correlation was also found between N 2. emissions and soil available nitrogen content NH + 4.

关键词： N_2. emissions the North China Plain agricultural soils chemical nitrogen organic manure

Estimation of annual actual evapotranspiration from nonsaturated land surfaces with conventional meteorological data

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Science China Earth sciences 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2. MIAO Qilong1 & YU Qiang2.1. Department of Geography, Nanjing institute of Meteorology, Nanjing 2.0044, China 2. institute of Geographic {2. and Natural resources Research, Chinese Academy of {2., beijing 1.01.1. China Nanjing Inst Meteorol Dept Geog Nanjing 210044 Peoples R China Chinese Acad Sci Inst Geog Sci Beijing 100101 Peoples R China Chinese Acad Sci Nat Resources Res Beijing 100101 Peoples R China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 30 years data from 432.weather stations and 51.0}hydrological stations in China, the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of 1.%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.

Numerical study on scanning radiation acoustic field in formations generated from a borehole

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Science China(Physics,Mechanics & Astronomy) 2005年第2期48卷 247-256页

作者： CHE Xiaohua1. ZHANG Hailan1. QIAO Wenxiao2.& JU Xiaodong2.1. institute of Acoustics, Chinese Academy of {1., {2. 1.0080, China 2. Faculty of Natural resources & Information Technology, University of Petroleum, {2. 1.2.49, China institute of Acoustics Chinese Academy of Sciences Beijing 100080 China Faculty of Natural resources & Information Technology University of Petroleum Beijing 102249 China

Numerical study on scanning radiation acoustic field in formations generated by linear phased array transmitters in a fluid-filled borehole is carried out using a real axis integration (RAI) method. The main lobe width of the acoustic beams and the incident angle on the borehole wall can be controlled by means of adjusting parameters, such as the element number and the delay time between the neighboring array elements of linear phased array transmitter. The steered angle of longitudinal waves generated in the formation satisfies the Snell’s law for plane waves when the incident angle on the borehole wall is less than the first critical angle. When the lobe width of the acoustic beams is narrow and the steered angle is less than the first critical angle, the acoustic field in the formation can be approximately calculated given that the linear phased array is put in the formation without borehole. The technique of scanning radiation acoustic field can be applied to enhancing investigation resolution and signal-to-noise ratio in crosswell seismic survey and borehole acoustic reflection imaging.

关键词： formation, linear phased array transmitter, steered angle, RAI, scanning radiation.

Effective solutions to a global 3D visual system in networking environments

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Science China Earth sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2. ZHANG Yan3, YANG Chongjun2. LIU Suhong1, REN Yingchao2. RUI Xiaoping2.& LIU Donglin2.1. State Key Laboratory of Remote Sensing sciences, School of Geography and Remote Sensing, {1. Normal University, {1. 100875, China 2. State Key Laboratory of Remote Sensing sciences, institute of Remote Sensing Applications, Chinese Academy of sciences, {1. 101001, China 3. institute of geographical sciences and Natural {1.} Research, Chinese Academy of sciences, {1. 101001, China 1. State Key Laboratory of Remote Sensing sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. Chinese Academy of {1. State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. institute of {1. {2. and Natural resources Research Chinese Academy of Sciences 101001 Beijing China

The development of Web-based global 3D visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1. 2., ZHANG Youshui 3 1. {1. of Mountain Hazards and Environment, Chinese Academy of {1., Chengdu 61.041. Sichuan, China 2. Graduate University of Chinese Academy of {1., beijing 1.0049, China 3. {1. of geographical {1. and Natural resources Research, Chinese Academy of {1., beijing {1.} China institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of Chinese Academy of sciences 100049 Beijing China institute of {1. {2. Natural resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)