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The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, China

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science China Earth sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3 & WANG Lei2.1. institute of Tibetan Plateau research, Chinese Academy of {2.s, beijing 100085, China 2. Faculty of Earth {2.s and Mineral resources, China University of Geo{2.s, beijing 100083, China 3. Tianjin institute of Geology and Mineral resources, Tianjin 300170, China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China Faculty of Earth sciences and Mineral resources China University of Geosciences Beijing China Tianjin institute of Geology and Mineral resources Tianjin China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

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On the Laws and Causes of Socio-economic Territorial Differentiation in Minority Areas in China

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Chinese Journal of Population,resources and Environment 2009年第1期7卷 30-36页

作者： Xue Mei Dong Suocheng institute of geographical {2. and Resource research Chinese Academy of Sciences Beijing 100101 China Graduate University Chinese Academy of Sciences Beijing 100039 China

On the basis of applying quantitative and qualitative approaches as well as GIS technology, this paper established an index system to make a comprehensive evaluation on socio-economic development of minority areas in China. The result showed that socio-economic development in minority area presents a series of characteristics that the north is high and the south is low, center-margin pattern is obvious and the areas with middle and lower development indices are distributed centrally and continuously. However, the causes of the socio-economic characteristics mainly include natural conditions, economic development basic, population cultural quality, re-gional combination and development conditions of mineral and energy resources, informal institutional factors and distribution of major traffic lines..

关键词： minority areas socio-economic development laws of territorial differentiation

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Spatial heterogeneity of the driving forces of cropland change in China

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science China Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2. WANG Jinfeng1, LIU Mingliang4,1 & MENG Bin1,2.3 1. institute of Geographic sciences and {2. resources research, Chinese Academy of sciences, beijing 100101, China 2. Graduate School of the Chinese Academy of sciences, beijing 100039, China 3. College of Arts and sciences of beijing Union University, beijing 100083, China 4. School of Forestry and Wildlife sciences, Auburn University, Auburn, Alabama, AL36849, USA institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of sciences Beijing China School of Forestry and Wildlife sciences Auburn University Auburn Alabama USA College of Arts and sciences of beijing Union University Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2.00 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in China. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of China, natural condition changes and geographical background were the main constraints and drivers, while in Eastern China, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in China recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, China.

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Relationship between Surface Pollen and Modern Vegetation in Southwestern China

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Journal of Mountain science 2010年第2期7卷 176-186页

作者： PAN Tao DAI Erfu and WU Shaohong institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of sciences BeO'ing 100049 China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China

Based on the pollen data obtained from thirty-five surface soil samples and investigated vegetation data from seven plant quadrats,the quantitative relationship between surface soil pollen and modern vegetation are studied in the longitudinal range-gorge region (LRGR) in Southwestern China.R-values (referring to pollen assemblages) are calculated with pollen percentage and plant *** coefficients of similarity between pollen and vegetation are *** results show that the pollen assemblages on surface soil of all vegetation zones can basically represent the native vegetation,but the pollen assemblages are not fully according with the *** is due to the influencing factors including pollen preservation ability,pollen production,amount of exotic pollen and pollen *** pollen representation in surface soil is different in families and *** pollen of woody plants such as Pinus,Tsuga,Alnus,Fagus and castanopsis are over-representative,but those of Quercus,Carpinus Myrica,Elaeocarpaceae,Ericaceae,Theaceae and Llex are underrepresentative;the pollen of herbaceous plants such as Artemisia and Rubiaceae are over-representative,while those of others including Gramineae and Araliaceae are *** R-values of the same taxon pollen in different vegetation zones are different,depending on their distances from the pollen *** coefficients of the similarity between plant communities and pollen assemblages are mostly over 70%,which indicate again that the surface soil pollen and spores assemblages can represent the *** is concluded that there is a good corresponding relationship between surface pollen assemblages and native vegetation in LRGR,and it is of great significance for reconstructing the past vegetation and paleoclimate using quantitative fossil pollen data in this region.

关键词： Longitudinal range-gorge region (LRGR) Pollen assemblage Vegetation R-value Coefficient of similarity

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IMPACTS OF FLOOD EVENTS IN COARSE SEDIMENT-PRODUCING AREAS ON CHANNEL SILTATION AND FLUVIAL PROCESS OF THE LOWER YELLOW RIVER

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International Journal of Sediment research 2007年第2期22卷 142-149页

作者： Ou-yang ZHANG1, Xiufu FENG2.and Jiong-xin XU31 Bureau of Hydrology, Changjiang Water resources Commission, Hubei, Wuhan 430010, China2.Chengdu University of technology, Sichuan, Chengdu 610059, China3institute of Geographic {2.s and natural resources research, cas, beijing 100101, China Changjiang Water resources Commiss Bureau Hydrol Wuhan 4310010 Peoples R China Chengdu Univ Technol Chengdu 610059 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China

The method of multiple regression is used to analyze the influences of flood events from the coarse sediment producing areas on the channel siltation and fluvial process of the lower Yellow River based on the flood events from 1950 to 1985. The results showed that the flood events from the coarse sediment producing areas carry larger amounts of sediment load and coarser particle sizes than from other source areas, which increases deposition in the lower river channel. And there exist good correlations between channel siltation of the lower reaches of the Yellow River and the coming water and sediment of flood events from the coarse sediment producing areas. Through these correlations, the amounts of sediment deposition in the lower river channel could be roughly estimated based on the runoff and sediment load of flood events from the coarse sediment producing areas. The sediment deposition caused the fluvial process. There exists a complex response of channel form change to the coming water and sediment load of flood events from the coarse sediment producing areas. When the sediment concentration is smaller than 2.0kg/m3, the ratio between wide-depth ratio after flood and wide-depth ratio before flood((B/h)a / (B/h)b) will increase with the increase of the maximum sediment concentration; when the sediment concentration is near 2.0kg/m3, (B/h)a / (B/h)b reaches the maximum value; and when the sediment concentration reaches the limits of hyperconcentrated flow, (B/h)a / (B/h)b will decrease with the increase of the maximum sediment concentration. Generally, flood events from the coarse sediment producing areas made channel form of the lower Yellow River deeper and narrower, but a large amount of sediment deposition simultaneously occurs. So, the impacts of flood events from the coarse sediment producing areas on the channel of the lower Yellow River are lessened.

关键词： Channel siltation Fluvial process Coarse sediment-producing areas Flood events Yellow River basin

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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 {12. 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 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 China Graduate University of Chinese Academy of sciences Beijing China Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing China China Key Laboratory of Ecological Network Observation and Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Ordos Forestry Sand Control science institute Dongsheng China Inner Mongolia Biomass Thermoelectricity Limited Company Wushen 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

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Spatial pattern of land cover change in China's semiarid environment

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Journal of Arid Land 2009年第1期1卷 16-25页

作者： BaoLin LI1 and QiMing ZHOU2.1 State Key Laboratory of Environment and resources Information System, institute of {2. sciences and resources research, Chinese Academy of sciences, beijing 100101, China 2.Department of Geography, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China State Key Laboratory of Environment and resources Information System Institute of Geographical Sciences and Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Geography Hong Kong Baptist University Kowloon Tong Hong Kong

This study seeks a routine to quantify spatial pattern of land cover changes in semiarid environment of China based on post-classification comparison method. The method consists of three major steps: (1) the image classification and unification of classified results based on two-level land cover classification themes, (2. the establishment of land cover change classes based on an unification land cover classification theme, (3) the reclassification and mapping of land cover change classes with three overall classes including no-change, gain and loss based on the unification land cover class. This method was applied to detect the spatial pattern of land cover changes in Yinchuan Plain, one of famous irrigation agricultural zones of the Yellow River, China. The results showed the land cover had undergone a remarkable change from 1991 to 2.02.in the study area (the changed area was over 30%). Rapid increase of cropland (12.5%), built-up area (131.4%) and rapid decrease of bare ground (51.7%) were alarming. The spatial pattern of land cover changes showed clear regional difference in the study area and was clearly related to human activities or natural factors. Thus, it obtained a better understanding of the human impact on the fragile ecosystem of China’s semiarid environment.

关键词： change detection spatial pattern land cover semiarid zone of China remote sensing human activities

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Effect of Sprinkler and Border Irrigation on Topsoil Structure in Winter Wheat Field

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Pedosphere 2010年第4期20卷 419-426页

作者： SUN Ze-Qiang KANG Yao-Hu JIANG Shu-Fang Soil and Fertilizer institute Shandong Academy of Agricultural Sciences Jinan 250100 (China) institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing 100101 (China)

A two-year experiment was carried out on the effect of sprinkler irrigation on the topsoil structure in a winter wheat field. A border-irrigated field was used as the control group. The total soil porosity, pore size distribution, pore shape distribution, soil cracks and soil compaction were measured. The sprinkler irrigation brought significant changes to the total soil porosity, capillary porosity, air-filled porosity and pore shape of topsoil layers in comparison with the border irrigation. The total porosity and air-filled porosity of the topsoil in the sprinkler irrigation were higher than those in the border irrigation. The changes in the air-filled and elongated pores were the main reasons for the changes in total porosity. The porosities of round and irregular pores in topsoil under sprinkler irrigation were lower than those under border irrigation. Sprinkler irrigation produced smaller soil cracks than border irrigation did, so sprinkler irrigation may restrain the development of macropore flow in comparison with border irrigation. The topsoil was looser under sprinkler irrigation than under border irrigation. According to the conditions of topsoil structure, it is preferable for crops to grow under sprinkler irrigation than under border irrigation.

关键词： macropore flow soil compaction soil crack soil pore shape soil porosity

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Discussion on the dispersion & agglomeration of aircraft industry

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Journal of Pharmaceutical Analysis 2009年第3期21卷 192-197,208页

作者： Bo Chu1,2.. institute of Geographic sciences and {2. resources research,cas,beijing 100101 2. Graduate School of the Chinese Academy of sciences,beijing 100049,China. institute of Geographic sciences and {2. resources research CAS Beijing 100101 Graduate School of the Chinese Academy of sciences Beijing 100049 China

The aircraft industry is crucial to the economy and security of a nation. In this paper,the spatial characteristics and patterns of the aircraft industry are analyzed on different spatial scales. It is found that there is a ’Matthew effect’ in the global aircraft industry and the spatial evolution of the industry is consistent with the industrialization process of the whole country. It is also revealed that the spatial evolution of the country is driven by both the centripetal forces including capital,talents,technology and agglomeration economies and the centrifugal forces including the comparative advantage,cost & risk sharing,emerging markets,development policy for less-developed regions and the military imperative. These forces have both market-stabilizing and market-disrupting effects on the spatial evolution of the aircraft industry. The study suggests that lessons drawn from the experiences in the United States and France are expected to be conducive to the rise of China’s aircraft industry in the future.

关键词： aircraft industry dispersion agglomeration spatial evolution

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Relationship between precipitation and the infiltration depth over the middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley

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Progress in natural science:Materials International 2008年第9期18卷 1123-1128页

作者： Zhixin Hao a, Jingyun Zheng a, Quansheng Gea,, Xifeng Guoa,b a institute of geographical {2.s and natural resources research, Chinese Academy of {2.s, 11A, Datun Road Anwai, Chaoyang District, beijing 100101, China b Graduate University of Chinese Academy of {2.s, beijing 100049, China institute of geographical {2.s and natural resources research Chinese Academy of Sciences 11A Datun Road Anwai Chaoyang District Beijing 100101 China Graduate University of Chinese Academy of sciences Beijing 100049 China

The purpose of the paper is to extract and make the best use of rainfall information contained in the Chinese historical archives of Qing Dynasty, and reconstruct the precipitation series during *** study followed the Yu-Fen-Cun (rainfall infiltration depth) observation method in Qing Dynasty, to conduct soil infiltration experiment under the natural rainfall conditions during *** related parameters, such as precipitation, intensity, initial soil moisture content and infiltration depth have been measured at 10 stations (east of 105°E, 30°-40°N) with representative climatic conditions and soil physical texture in the middle and lower reaches of the Yellow River and Yangtze-Huaihe River *** statistical results indicate that precipitation is the primary infiuencing factor to infiltration depth and is positively correlated with the infiltration ***, the efiects of every factor on infiltration depth are significantly difierent between the middle and lower reaches of the Yellow River and Yangtze-Huaihe River ***, the relationship equations of precipitation and infiltration depth are established for each site, most of which can pass over 60% of the variance explanations and provide quantitative models to reconstruct the precipitation series using Yu-Fen-Cun records in Qing Dynasty.

关键词： Middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley Precipitation Infiltration depth Yu-Fen-Cun Climate reconstruction

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