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Science china(Technological sciences) 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, 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 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 29.7%―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

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 sciences, beijing Normal University, beijing 100875, china 2. institute of Geographic Science and natural resources research, beijing 100101, 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 1982—1998, soil moisture of all layers of soil-profile (0—1 m) in the Yellow River basin over the 17 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 1982 to 1988 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 17 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.

Relationships between tree-ring width index and NDVI of grassland in Delingha

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Chinese Science Bulletin 2006年第9期51卷 1106-1114页

作者： HE Jicheng1,3 & SHAO Xuemei1,21. institute of geographical sciences and natural resources research, Chinese Academy of sciences, beijing 100101, china 2. institute of Tibetan Plateau research, Chinese Academy of sciences, beijing 100085, china 3. Graduate School of Chinese Academy of sciences, beijing 100039, china institute of geographical sciences and natural resources research Chinese Academy of Sciences Beijing China Graduate School of Chinese Academy of sciences Beijing China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China

Using five well-replicated Qilian juniper (Sabina przewalskii Kom.) tree-ring width index se- ries, monthly normalized difference vegetation index (NDVI) of grassland, and climatic data from 1982 to 2001, the relationships between tree-ring width index, NDVI of grassland, and climatic data were analyzed firstly. Then, the relationship between tree-ring width index and NDVI of grassland was explored. The re- sults showed that: (1) Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha. (2) There were sig- nificant relationships between five tree-ring width index series (DLH1-DLH5) and monthly NDVI of grassland from June to September, with the most significant relationship being between tree-ring width index series and NDVI of grassland in August. (3) The PC1 (the first principal component derived from DLH1-DLH5 series) exhibited good agreement with monthly NDVI of grassland in the grass growth sea- son (from June to September) and the averaged NDVI in the growth season, which was attributed to their common responses to water-supply limit in Delingha. This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1.

关键词：圆柏祁连山 NDVI 草原年轮宽度指数

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 255049, china 2. institute of geographical sciences and natural resources research, Chinese Academy of sciences, beijing 100101, china Shandong University of Technology Zibo Shandong 255049 China institute of geographical sciences 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 1990s 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

Function of Agricultural Land Use and Its Evolvement in Peri-urban Area: A case Study of beijing

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Chinese Journal of Population,resources and Environment 2007年第2期5卷 67-71页

作者： Yuan Hong, Cai Jianming, Jiang Fang, Liu Shenghe institute of geographical sciences and natural resources research, Chinese Academy of sciences, beijing 100101, china institute of geographical sciences and natural resources research Chinese Academy of Sciences Beijing 100101 China

Rapid urbanization in beijing stimulates the urban land expansion and diminishes available agricultural land. Monofunctional agricultural land use can not meet the demand of the devel- opment of the multifunctional agriculture and urbanization any more, so multifunctional agricultural land use is going to be promoted in the city. This article proposes the evolvement of the land use change from 1992 to 2004 and discusses some evolvement views.

关键词： function agricultural land use peri-urban 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 sciences 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 sciences and natural resources,Chinese Academy of sciences,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.

CH_4 uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,china

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Science china Earth sciences 2010年第7期53卷 977-983页

作者： GENG YuanBo1, LUO GuangQiang1,2 & YUAN GuoFu1 1 institute of Geographic sciences and natural resources research, Chinese Academy of sciences, beijing 100101, china 2 Graduate University of Chinese Academy of sciences, beijing 100049, china 1. institute of Geographic sciences and natural resources research Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The influence of near ground atmosphere CH4 concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4 uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, china. The results showed that CH4 uptake flux was positively correlated with near ground atmosphere CH4 concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4 flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.52 (natural conditions, 1.51 (aboveground plants were excluded), and 2.00 mg m?2 d?1 (all plants were removed), respectively. The difference between the CH4 flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4 uptake flux is smaller than that of roots or roots-removing process. CH4 uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.36–7.86). The Leymus chinensis steppe acts as a sink for CH4, and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method

Influence of “Holiday Tourism Circle of beijing” on Chengde Tourism Spatial Alteration and Reconstruction

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Chinese Journal of Population,resources and Environment 2006年第4期4卷 38-42页

作者： Li Chen1,2,Cheng Shengkui2,Chen Yuansheng2,Zhang Yingqiu1 1.College of Arts&Science,beijing Union University,beijing 100083,china 2.institute of geographical Science and natural resources research,cas,beijing 100101,china College of Arts & Science Beijing Union University Beijing 100083 China institute of geographical Science and natural resources research CAS Beijing 100101 China Institute of Geographical Science and Natural Resources Research CAS Beijing 100101 China Institute of Geographical Science and Natural Resources Research CAS Beijing 100101 China College of Arts & Science Beijing Union University Beijing 100083 China

Chengde City,famous for its cultural sightseeing tourism industry,and is located in china's"Capital Holiday Tourism Circle".This location is advantageous,because of the recent boom in china's national tourism *** industry has gone through several structural and development changes with in the past several years.A result of these restructuring patterns is the great changes concerning competitive and cooperative relations among tourism destinations,which have precipitated the decline of the traditional sightseeing pattern. Northern china's"Capital Holiday Tourism Circle"is one of nine key areas within the Chinese tourism industry under development during the Eleventh Five-Year *** the present article the method of"Distance Decline of The Tourist Flow"was used to define the flow of tourists in the Capital Holiday Tourism Circle and its influence upon Chengde's tourism spatial distribution.3 aspects will be discussed:(1)The transformation from sightseeing to leisure markets makes the change possible in Chengde's tourism spatial pattern.(2)The location advantage(adjacent to beijing and Tianjin) also leads to the change in Chengde tourism spatial pattern.(3)The establishment of freeways also contributes to a great degrees of change. The rapid development of leisure tourism might lead to the change from nucleus model to a diversified one within Chengde's ***,Chengde is developing the tourism industry with the central heritage area as the nucleus and the northern forest, pasture,southern mountain,and rivers as its periphery.

关键词： china Capital Holiday Tourism Circle Chengde city tourism space

Urban Water Supply Industry Marketization of china in View of Public Water Service and Water Resource Management

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Chinese Journal of Population,resources and Environment 2010年第2期8卷 55-60页

作者： Wang Yining 1,2 1.institute of Geographic Science and natural resources research,cas,beijing 100101,china 2.Graduate School of the Chinese Academy of sciences,beijing 100049,china institute of Geographic Science and natural resources research CAS Beijing 100101 China Graduate School of the Chinese Academy of sciences Beijing 100049 China

Started with the discussions on the value orientation of urban water supply industry marketization,the article points out that the current urban water supply industry marketization reform is inconsistent with the goal of public water service equalization to some *** article also analyzes the problems emerged in urban water supply industry marketization reform and various rea-sons in view of efficiency and *** efficiency and fairness oriented management model is built in this article to illustrate how the government should conciliate interests of various communities involved in the process of marketization reform of the urban water supply industry so as to actualize the coordination of efficiency and *** the end,an assumption on urban water price is put forward to help achieve the public water service equalization.

关键词： urban water supply industry marketization public water service water resource management

STATISTICAL RELATIONS BETWEEN GEOMORPHIC PARAMETERS——A casE STUDY OF THE YUNNAN REACH OF THE LANCANGJIANG RIVER IN SOUTHWESTERN china

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International Journal of Sediment research 2007年第2期22卷 131-141页

作者： Suiji WANG1, Shaohong WU2 and Erfu DAI31,3 Key Laboratory of Water Cycle and Related Land Surface Processes, institute of geographical sciences and natural resources research, Chinese Academy of sciences, beijing, 100101, china, 2 Key Laboratory of Water Cycle and Related Land Surface Processes, institute of geographical sciences and natural resources research, Chinese Academy of sciences, beijing, 100101, china, Chinese Acad Sci Inst Geog Sci & Nat Resources Res Key Lab Water Cycle & Related Land Surface Proc Beijing 100101 Peoples R China

The properties of rivers and their catchments can be expressed by statistical relationships between geomorphic parameters. These statistical relationships may reveal some inherent differences in geomorphic evolution for different reaches or different order tributaries of a river basin. A case study was undertaken of the Yunnan reach of the Langcangjiang River. The catchment area, channel length and gradient of the first-, second- and third-order tributaries all with catchment areas larger than 100 km2 in the Yunnan reach were the main geomorphic parameters evaluated. The correlation between catchment area and channel length as well as between catchment area and channel gradient with respect to the total tributaries, different reach tributaries, and different order tributaries were revealed using statistical methods. In general, the channel length as a function of catchment area, was best expressed by a quadratic function where channel length increases with increasing catchment area (half parabola), while the channel gradient as a function of catchment area is best expressed by an exponential decay function. Comparison of the best-fit formulas revealed the following phenomena: the lower Yunnan reach tributaries and the first-order tributaries have a dominant effect on geomorphic parameters of the total tributaries. In addition, the statistical relationships indicate that the river geomorphic system in the upper and lower Yunnan reaches evolved differently. This study method used to differentiate river characteristics by determining statistical relationships between geomorphic parameters may be extended to other rivers and their catchments.

关键词： River catchment Geomorphic parameter Correlation River characteristics