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Land use and landscape pattern change: a linkage to the construction of the Qinghai-Xizang Highway

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Journal of geographical sciences 2002年第3期12卷 253-265页

作者： YAN Jianzhong, ZHANG Yili, LIU Linshan, LIU Yanhua2, ZHENG Du (1. Inst. of Geographic sciences and natural resources research, cas, beijing 100101, china 2. The Ministry of Science and Technology, beijing 100101, china 3. College of resources and Enviro Inst. of Geographic sciences and natural resources research CAS Beijing China College of resources andEnvironment Southwest Agricultural University Chongqing China The Ministry of Science and Technology Beijing China

Based on digital land use data from 1995 to 2000 and road data, the land use and landscape changes of Golmud, Qumaleb and Zhidoi are studied on a macro-scale. Land use and landscape changes in highway buffer zones and city expansion are special subjects. A new formula is used to define the exact degree of dynamic land use. To adequately define land use and landscape pattern changes, the buffer zones, illustrating the changes at different distances from the road, are recognized with ArcGIS 8.1 software. Prominent changes took place in land use and landscape patterns from 1995 to 2000, and the area of built-up land increased by 323.8%. The comprehensive degree of dynamic land use is 2.25, and the degree of dynamic land use of built-up land is the highest, followed by cultivated land. Woodland has the lowest value. The used degree index of land resources declined by 38.8 from 1995 to 2000. Landscape changed dramatically which influenced ecological processes immensely. Different from the corridor effect of other traffic routes, the corridor effect of this section of road is not obvious and its “point” radiation effect can be easily seen. The expanding range of Golmud City is confined to a 3 km buffer, while for Wudaoliang, it is 1 km. No land use change happened in the Nanshankou buffer.

关键词： land use change comprehensive index of the degree of land use diagnostic index of landscape degree of dynamic land use Qinghai-Xizang Highway

Origin Distribution Patterns and Floating Population Modeling:Yiwu City as a Destination

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Chinese geographical Science 2012年第3期22卷 367-380页

作者： LI Hongsheng WANG Yingjie HAN Jiafu State Key Laboratoty of resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Existing quantitative migration studies are mainly at the inter-region or inter-province level for lacking of detailed geo-referenced migration ***,few of them integrate explorative spatial data analysis and spatial regression model into migration *** on aggregated registered floating population data from 2005 to 2008,the phenomena that population floating to Yiwu City in Zhejiang Province is analyzed at the provincial and county *** spatial layout of Yiwu's pull forces is proved as a V-shaped pattern excluding Sichuan Province based on map visualization *** the migration ratio in 2007 as an explanatory variable,two models are compared using ordinary least square,spatial error model and spatial lag model methods for county-level data in Jiangxi and Anhui *** model with migration stock provides an improved fitting over the model without migration stock according to the model fitting *** floating population flocking into Yiwu City from Jiangxi is determined mostly by migration stock while the determinant factors are migration stock and distance to Yiwu City for *** distance-decay effect is true for migration flow from Anhui to Yiwu City while the distance rule is not confirmed in Jiangxi with the best fitting *** correlation between per capita net income of rural labor forces and migration ratio is not significant in Jiangxi and significant but at the 0.1 level only in *** analysis shows that the distance,income and man-land ratio are important factors to explain population floating at earlier ***,as the dynamic population floating process evolves,the determinant factor would be migration stock.

关键词： floating population origin distribution visualization spatial regression model Yiwu City GIS

Cosmogenic ^(21)Ne concentrations and exposure ages of summit bedrocks in the Grove Mountains,Antarctica

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Science china Earth sciences 2010年第4期53卷 518-521页

作者： KONG Ping1,2,DING Lin2,LAI QingZhou2 & HUANG FeiXin3 1 Key Laboratory of the Earth’s Deep Interior,institute of Geology and Geophysics,Chinese Academy of sciences,beijing 100029,china 2 Key Laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau research,Chinese Academy of sciences,beijing 100085,china 3 institute of Mineral resources research,china Metallurgical Geology Bureau,beijing 100025,china 1. Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China2. Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China3. Institute of Mineral Resources Research China Metallurgical Geology Bureau Beijing 100025 China

Various sources of 21Ne and 22Ne exist in surface rocks:cosmogenic,in situ nucleogenic from internal U and Th,trapped crustal nucleogenic and trapped *** paper reports the first measurement,in china,of cosmogenic 21Ne and 22Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 21Ne and ***-heating experiments show that concen-trations of cosmogenic 21Ne and 22Ne in summit bedrock samples R9202 and R9203 from Grove Mountains,Antarctica,are(3.83±0.87)×108 and(5.22±0.51)×108 atoms/g,*** corresponding minimum exposure ages are 2.2±0.5 and 3.0±0.3 *** indicates that the ice sheet in East Antarctica was uncovered the crest of Mount Harding,a typical nunatak in Grove Mountains,since at least mid-Pliocene.

关键词： 21Ne cosmogenic nuclide exposure age Antarctica Grove Mountains

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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Science china(Technological sciences) 2004年第z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, LIU Changming1, , WU Xianfeng2 2 & ZHAO Weimin3 1. Key Laboratory of Water Cycle & Related Land Surface Processes, institute of Geographic Science and natural resources research, Chinese Academy of sciences, beijing 100101, china 2. institute of Environmental Science, beijing Normal University, beijing 100875, china 3. Water resources Conservation Committee of Yellow River, Zhengzhou 450003, china Chinese Acad Sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China beijing Normal Univ Inst Environm Sci Beijing 100875 Peoples R China Water resources Conservat Comm Yellow River Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.

Quantitative estimation of the shrub canopy LAI from atmosphere-corrected HJ-1 CCD data in Mu Us Sandland

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Science china Earth sciences 2010年第S1期53卷 26-33页

作者： CHEN Wei1,2,CAO ChunXiang1,HE QiSheng1,2,GUO HuaDong3,ZHANG Hao1,2,LI RenQiang4,ZHENG Sheng1,2,XU Min1,2,GAO MengXu1,2,ZHAO Jian1,2,LI Sha1,NI XiLiang1,2,JIA HuiCong1,JI Wei1,TIAN Rong1,2,LIU Cheng1,2,ZHAO YuXing5 & LI JingLu6 1 State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the institute of Remote Sensing Applications of Chinese Academy of sciences and beijing Normal University,beijing 100101,china 2 Graduate University of Chinese Academy of sciences,beijing 100049,china 3 Center for Earth Observation and Digital Earth,Chinese Academy of sciences,beijing 100190,china 4 china Key Laboratory of Ecological Network Observation and Modeling,institute of geographical sciences and natural resources research,Chinese Academy of sciences,beijing 100101,china 5 Ordos Forestry Sand Control Science institute,Dongsheng 017000,china 6 Inner Mongolia Biomass Thermoelectricity Limited Company,Wushen 017300,china 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China 2. Graduate University of Chinese Academy of sciences Beijing 100049 China 3. Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China 4. china Key Laboratory of Ecological Network Observation and Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 5. Ordos Forestry Sand Control Science institute Dongsheng 017000 China 6. Inner Mongolia Biomass Thermoelectricity Limited Company Wushen 017300 China

The leaf area index(LAI) is an important ecological parameter that characterizes the interface between vegetation canopy and the *** addition,it is used by most process-oriented ecosystem *** paper investigates the potential of HJ-1 CCD data combined with linear spectral unmixing and an inverted geometric-optical model for the retrieval of the shrub LAI in Wushen Banner of Inner Mongolia in the Mu Us ***(Moderate Resolution Atmospheric Radiance and Transmittance Model) was used for atmospheric *** was extracted using the threshold of the normalized difference vegetation index,with which water bodies and farmland were separated,in combination with a vegetation map of the People's Republic of china(1:1000000).Using the geometric-optical model,we derive the per-pixel reflectance as a simple linear combination of two components,namely sunlit background and *** fraction of sunlit background is related to the shrub *** the support of HJ-1 CCD data,we employ linear spectral unmixing to obtain the fraction of sunlit background in an atmospherically corrected HJ *** addition,we use the measured shrub canopy structural parameters for shrub communities to invert the geometric-optical model and retrieve the pixel-based shrub *** total,18 sample plots collected in Wushen Banner of Inner Mongolia are used for *** results of the shrub LAI show good agreement with R2 of 0.817 and a root-mean-squared error of 0.173.

关键词： shrub leaf area index inversion HJ-1 data geometric-optical model MODTRAN Mu Us Sandland

中国科学院生态系统网络观测与模拟重点实验室CERN综合研究中心研究成果与发展

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自然资源学报 2010年第9期25卷 1458-1467页

作者： Synthesis research Center of Chinese Ecosystem research Network,cas(institute of Geographic sciences and natural resources research,cas,beijing 100101,china) 中国科学院地理科学与资源研究所北京100101

介绍了中国生态系统研究网络(CERN)综合研究中心成立以来的发展历程和主要研究成果,以及未来研究方向及预期发展。取得的代表性研究成果主要有:CERN动态监测数据与生态系统空间信息数据管理和共享系统的开发、陆地生态系统碳和水热通量... 详细信息

介绍了中国生态系统研究网络(CERN)综合研究中心成立以来的发展历程和主要研究成果,以及未来研究方向及预期发展。取得的代表性研究成果主要有:CERN动态监测数据与生态系统空间信息数据管理和共享系统的开发、陆地生态系统碳和水热通量观测研究、陆地生态系统碳储量的时空格局特征研究、陆地生态系统多尺度模拟综合集成研究和青藏高原生态系统格局与全球变化相互作用关系研究等。未来的研究方向主要集中在陆地生态系统碳氮水循环及其耦合,区域碳汇功能动态,生态敏感区、脆弱区和过渡区对全球气候变化的响应与适应,生态监测、模拟与生态信息应用以及全球气候变化主要因子对生态系统关键过程的影响。未来除了履行CERN综合研究中心的基本职能外,争取在以上研究方向取得有国际影响的开拓性研究成果。

关键词： CERN 综合研究中心研究成果陆地生态系统

Accurate Quantification of Grassland Cover Density in an Alpine Meadow Soil Based on Remote Sensing and GPS

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Pedosphere 2005年第6期15卷 778-783页

作者： LIU Yan-Sui HU Ye-Cui PENG Liu-Ying institute of Geographic sciences and natural resources research Chinese Academy of Sciences Beijing 100101 （China） Graduate School of Chinese Academy of sciences Beijing 100039 （China）

The principles of remotely estimating grassland cover density in an alpine meadow soil from space lie in the synchronous collection of in situ samples with the satellite pass and statistically linking these cover densities to their image properties according to their geographic coordinates. The principles and procedures for quantifying grassland cover density from satellite image data were presented with an example from Qinghai Lake, china demonstrating how quantification could be made more accurate through the integrated use of remote sensing and global positioning systems (GPS). An empirical model was applied to an entire satellite image to convert pixel values into ground cover density. Satellite data based on 68 field samples was used to produce a map of ten cover densities. After calibration a strong linear regression relationship (r2 = 0.745) between pixel values on the satellite image and in situ measured grassland cover density was established with an 89% accuracy level. However, to minimize positional uncertainty of field samples, integrated use of hyperspatial satellite data and GPS could be utilized. This integration could reduce disparity in ground and space sampling intervals, and improve future quantification accuracy even more.

关键词： alpine meadow soil grassland cover density quantitative remote sensing Qinghai Lake

CHARACTERISTICS AND RATIONAL EXPLOITATION OF LAND resources IN XIZANG

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Chinese geographical Science 1996年第4期6卷 321-331页

作者： Li Mingsen (Commission for Integrated Survey of natural resources,the Chinese Academy of sciences, beijing 100101, PRC) Commission for Integrated Survey of natural resources the Chinese Academy of Sciences Beijing PRC

There is vast land in Xizang (Tibet), but the land suitable for agriculture is less and concentrated. There is a large quantity of land suitable for animal husbandry, but great differentiation in quality. The land suitable for forestry is in large quantity and high quality. The land in high, cold and dry region is very difficult for use. An of these chacteristics determine the Pedctive structure and scale and the distribution of agriculture, forestry and animal husbandry in Xizang. At present, the exploitation level of land resources in Xizang is low, the commodity production is backward and some of the land is in degradation. The exploitstion should be combined with the conservation of several kinds of land resources. Per unit pleduction of land staid be enhanced, the improvement of the grassland and the construction of artificial grassland should be carried out. They are the strategy and effective countermeasures for the improcement of economy, production conditions and the eco-environment in Xizang.

关键词： land resources productive potentiality Xizang land exploitation

Study of attenuation depths for MODIS bands in the Bohai Sea in china

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Acta Oceanologica Sinica 2009年第5期28卷 39-48页

作者： LIU Ying LI Guosheng institute of Geographic sciences and natural resources research Chinese Academy of Science Beijing 100101 China Xinjiang institute of Ecology and Geogrphy Chinese Academy of Science Urumqi 830011 China

An attenuation depth is defined for remote sensing purposes as a depth above which 90% of the arising light leaving the water surface is originated. The deeper the attenuation depth, the more information of water is detectable by remote sensing, then the more precise information of water is extracted. Meanwhile, the attenuation depth is helpful to know water layer （by its thickness） from which remote sensing will be able to extract information. A number of investigators are using the moderate resolution imaging spectroradiometer （or MODIS） for remote sensing of ocean color. It is necessary to have a rough idea of the effective attenuation depth of imagery in each of the spectral bands employed by the MODIS. The attenuation depth is directly determined from MODIS data. Though analyzing the spectral distribution of the attenuation depth on 7 August 2003 and the seasonal variation of the attenuation depth （551 nm） in the Bohai Sea indicated that： the spectral distribution of the attenuation depth for the spectral range between 400 to 700 nm is single-peak curve, and it’s similar and difference in different regions is consistent with other scholars’ results of zoning, moreover, it supports the Bohai Sea is case 2 water; the maximum attenuation depth shifts toward longer wavelengths, liking the red shift, with increase of turbidity of water, just like the maximum attenuation depth in the outside of the northwest coast of the Bohai Sea and the Bohai Strait is at 531nm, in the central of the Bohai Sea is at 551nm, in the region controlled by the Huanghe （Yellow） River, the region impacted by the old Huanghe River, the western side of the Liaodong Bay and the eastern side of the Liaodong Bay is at 555 nm; the seasonal change of the attenuation depth is the largest in the summer, followed by the fall, and the ranking of winter and spring in different regions is distinct. The attenuation depth in different regions is dissimilar： the order of the attenuation depth in different

关键词： attenuation depth MODIS Bohai Sea