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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, Beijing 100871, China 2. institute of geographical sciences and natural resources research, Chinese Academy of sciences, Beijing 100101, China 1. institute of Remote Sensing & GIS Peking University 100871 Beijing China 2. institute of geographical sciences 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 1970, 1986 and 1999 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 20%.

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

Hyperconcentrated flows as influenced by coupled wind-water processes

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Science China Earth sciences 2005年第11期48卷 1990-2000页

作者： XU Jiongxin institute of geographical sciences and natural resources research, Chinese Academy of sciences Key Laboratory of Water Cycle and Related Land Surface Processes, Chinese Academy of sciences, Beijing 100101, China 1. Key Laboratory of Water Cycle and Related Land Surface Processes Chinese Academy of Sciences Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Using data from more than 40 rivers in the middle Yellow River basin, a study has been made of the influence of coupled wind-water processes on hyperconcentrated flows. A simple “vehicle” model has been proposed to describe hyperconcentrated flows. The liquid phase of two-phase flows is a “vehicle”, in which coarse sediment particles are carried as solid-phase. The formation and characteristics of hyperconcentrated flows are closely related with the forma-tion and characteristics of this liquid-phase and solid-phase. Surface materials and geomorphic agents of the middle Yellow River basin form some patterns of combination, which have deep influence on the formation and characteristics of liquid- and solid-phases of hyperconcentrated flows. The combination of high percentages of relatively coarse material with low percentages of fine material appears in the area predominated by the wind process, where the supply of rela-tively coarse sediment is sufficient, but the supply of relatively coarse sediment is not. The com-bination of low percentages of relatively coarse material with high percentages of fine material appears in the area predominated by the water process, where the supply of fine sediment is sufficient, but the supply of fine sediment is not. In the area predominated by coupled wind-water processes appears the combination of medium percentages of coarse and fine materials, and thus both coarse and fine sediments are in relatively sufficient supply. The manner in which the mean annual sediment concentrations of liquid- and solid-phases vary with total suspended sediment concentration is different. With the increased total suspended sediment concentration, mean annual sediment concentration of liquid-phase increased to a limit and then remained constant; however, mean annual sediment concentrations of solid-phase in-creased continuously. Thus, the magnitude of total suspended sediment concentration depends on the supply conditions of relatively coarse sedime

关键词： river sediment, hyperconcentrated flows, liquid-solid two-phase flows, wind process, fluvial process, Yellow River

research on Jiuquan-Jiayuguan-Yumen Region's Dynamic Changing of Urbanization Based on Self-Organizing Model

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Chinese Journal of Population,resources and Environment 2005年第3期3卷 22-28页

作者： Li Ming 1,2 & Fang Chuanglin 2 1 Graduate School of the Chinese Academy of sciences, Beijing 100039,China 2.institute of geographical sciences and natural resources research, CAS, Beijing 100101, China Graduate School of the Chinese Academy of sciences Beijing 100039 China institute of geographical sciences and natural resources research CAS Beijing 100101 China

Based on the self-organizing modeling principle in the dissipative structure theory, the paper regards the migration coupling between the regions as the influence factor to create the model of regional urbanization simulation and prediction, which is more practical to simulate the space-time and dynamic evolvement characteristics of regional urbanization level. According to the historical data about the population and urbanization of Jiuquan, Jiayuguan andYumen cities, the past 50 years' dynamic evolvement trend is simulated and the following 50 years' dynamic evolvement trend is predicted with the urbanization dynamic evolvement model based on the self-organizing model. The analysis of effective factors such as economic increase, resources exploitation, ecosystem construction, traffic location, national policies, population migration are given, then the reasons of the dynamic evolvement differences of the three cities' urbanization are drawn. The study suggests that the self-organizing model is fit for the simulation of Jiuquan-Jiayuguan-Yumen regional urbanization level in the past 50 years, and the departure between the stimulant and the actual data is under 5%, so it can be used to predict the urbanization future of the three cities. The predicted results show that the regional population will reach 1.074 million and the regional urbanization level will be 72.56%.

关键词： self-organizing urbanization dynamic evolvement Jiuquan-Jiayuguan-Yumen region

Spatial distribution of surface rock fragment on hillslopes in a small catchment in wind-water erosion crisscross region of the Loess Plateau

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Science China Earth sciences 2008年第6期51卷 862-870页

作者： ZHU YuanJun1,2 & SHAO MingAn1 1 institute of Soil and Water Conservation, Chinese Academy of sciences and Ministry of Water resources, Northwest Agriculture and Forestry University, Yangling 712100, China 2.institute of geographical sciences and natural resources research, Chinese Academy of sciences, Beijing 100101, China 1. institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Northwest Agriculture and Forestry University Yangling 712100 China 2. institute of geographical sciences and natural resources research Chinese Academy of Sciences Beijing 100101 China

The cover and size distributions of surface rock fragment in hillslopes were investigated by using digital photographing and treating technique in a small catchment in wind-water erosion crisscross region of the Loess Plateau. The results indicated that the maximal cover of rock fragment was pre-sented at mid-position in steep hillslope. Rock fragment presented a general decreasing-trend along the hillslope in gentle hillslope. Rock fragment cover was positively related to gradient, rock fragment size decreased generally along the hillslope, and the size reduced with the gradient. The mean size of rock fragment was at a range of 6―20 mm in the steep hillslope, rock fragment size > 50 mm was rarely presented. The covers of rock fragment at different positions were markedly related to the quantities of rock fragment 2―50 mm accounted for 60% or more of the total area, dominating the distribution of rock fragment in the hillslopes.

关键词： wind-water erosion crisscross region of the Loess Plateau small catchment hillslope surface rock fragment cover and size

Reconstruction of temperature series in China for the last 5000 years

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Progress in natural Science:Materials International 2006年第8期16卷 838-845页

作者： GE Quansheng, WANG Shunbing and ZHENG Jingyun (institute of geographical sciences and natural resources research, Chinese Academy of sciences, Beijing 100101, China Graduate School of the Chinese Academy of sciences, Beijing 100039, China) [a]Chinese Academy of sciences Institute of Geographical Sciences and Natural Resources Research Beijing China [b]Graduate School of the Chinese Academy of sciences Beijing China

A temperature series with a 100 year resolution for the last 5000 years in China has been reconstructed by using 31 longterm temperature proxy series selected from recent publications in the last 20 years. The proxy records include pollens, stalagmites, lake-sediments, peat, ice cores and historical documents. The result reveals that in the millennial scale temperature variation it was warm in 3050-250 BC and it was cold in 250 BC-1950 AD. In the above two periods there were many stages of sub-scale temperature fluctuations. The result also shows an obvious temperature discrepancy on the century to multi-century scale between the Eastern Monsoon Region, the Qinghai-Tibet Region and the Northwestern Region in 2850 BC, 2350 BC, 1350 BC, 950-350 BC, 50-250 AD, and 550 AD. A comparison between the reconstructed series of this paper and some North Hemisphere temperature series indicates that in the longterm scale change, the temperature change in China is in phrase with that of the Northern Hemisphere during the last 5000 years, while on the century to multi-century scale there are differences at the beginning and end times, which may imply that temperature change does not occur simultaneously in different regions.

关键词： temperature series the last 5000 years China.

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. institute of geographical sciences and natural resources research, Chinese Academy of sciences, Beijing 100101, China 2. Laboratory for Earth Surface Processes, Peking University, Beijing 100871, China 1. institute of geographical sciences 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 1952―2003 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952―1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 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, 16 t?a?1 and 11 t?a?1, which account for 92% of total transfer fluxes of HCHs isomers. There were approximately 253t 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 1984 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 1983, and this percentage may descend to 0.5% after 20 years by prediction.

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

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.

A prototype auto-human support system for spatial analysis

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Progress in natural Science:Materials International 2006年第9期16卷 954-966页

作者： LI Lianfa and WANG Jinfeng (State Key Laboratory of resources & Environmental Information System, institute of geographical sciences & natural resources research, Chinese Academy of sciences, Beijing 100101, China) [a]State Key Laboratory of resources & Environmental Information System Institute of Geographical Sciences & Natural Resources Research Chinese Academy Sciences Beijing China

Spatial analysis is a multidisciplinary field that involves multiple influential factors, variation and uncertainty, and modeling of geospatial data is a complex procedure affected by spatial context, mechanism and assumptions. In order to make spatial modeling easier, some scholars have suggested a lot of knowledge from exploratory data analysis (EDA), specification of the model, fitness and diagnosis of the model, to interpretation of the model. Also an amount of software has improved some functionalities of spatial analysis, e. g. EDA by the dynamic link (GeoDa) and robust statistical calculation (R). However, there are few programs for spatial analysis that can automatically deal with unstructured declarative issues and uncertainty in machine modeling using the domain knowledge. Under this context, this paper suggests a prototype support system for spatial analysis that can automatically use experience and knowledge from the experts to deal with complexity and uncertainty in modeling. The knowledge base component, as the major contribution of the system, in support of the expert system shell, codes and stores declarative modeling knowledge, e.g. spatial context, mechanisms and prior knowledge to deal with declarative issues during the modeling procedure. With the open architecture, the system integrates functionalities of other components, e.g. GIS’ visualization, DBMS, and robust calculation in an interactive environment. An application case of spatial sampling, design and implementation of spatial modeling with such a system is demonstrated.

关键词： spatial analysis automatic support system modeling of spatial data artificial inference for modeling.

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

Temperature variations recovered from tree-rings in the middle Qilian Mountain over the last millennium

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Science China Earth sciences 2005年第4期48卷 521-529页

作者： LIU Xiaohong1,2, QIN Dahe1, SHAO Xuemei , CHEN Tuo1 & REN Jiawen12 1. Cold and Arid Regions Environmental and Engineering research institute, Chinese Academy of sciences, Lanzhou 730000, China 2. institute of geographical sciences and natural resources research, Chinese Academy of sciences, Beijing 100101, China 1. Cold and Arid Regions Environmental and Engineering research institute Chinese Academy of Sciences 730000 Lanzhou China 2. institute of geographical sciences and natural resources research Chinese Academy of Sciences 100101 Beijing China

Based on the cross-dated tree-ring samples collected from the middle Qilian Moun- tain, a standard ring-width chronology had been developed, which covered the period AD 1000 to 2000. The correlations between the chronology and climatic records from the nearby meteorological stations indicated that temperature was the dominant climatic factor for tree growth at upper timberline, and the most important climatic factor for the tree growth in the area was the mean temperature from previous December to current April. The temperature variations recovered from the ring-width data showed a cold period during the “Little Ice Age” and the con- tinuous warming during the twentieth century. Comparison between the ring-width chronology and δ18O records from the Dunde ice core in the Qilian Mountain indicated that there was a con- sistent trend in both time series. A significant correlation existed between our ring-width chro- nology and the Northern Hemispheric temperature, suggesting that the climate changes in the Qilian Mountain were not only driven by regional factors, but also responsive to the global cli- mate.

关键词： middle Qilian Mountain, tree-ring width chronology, temperature variations.