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SEDIMENT HAZARDS IN THE LOWER YELLOW RIVER

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International Journal of Sediment Research 1999年第2期14卷 25-30页

作者： SHI Changxing (Supported by the National natural science Foundation of China) (institute of Geography, Chinese Academy of sciences, China)

The main sediment hazards in the lower Yellow River are flooding, channel erosion, desertification of cultivated lands, waterlogging. and soil salinization. Some of the hazards are the direct results of sediment movement and the others are related with sediment movement by the special landforms which themselves are the results of sediment movement. On the one hand, the sediment hazards,such as flooding. bank erosion and soil salinization, are aggravated by serious sediment accumulation in the Yellow River channel and irrigation canals due to heavy sediment load of the rived On the other hand, the distribution of the sediment deposit of different grain sizes is also a main factor influencing flooding, desertification, waterlogging and soil salinization hazards. The paper suggests to change the distribution of sedimentation as a measure of mitigating sediment hazards.

关键词： Sediment hazard The lower Yellow Rived Mitigation of sediment hazard

An integrated approach to scaling issues in environmental change study

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Journal of geographical sciences 2000年第4期10卷 45-52页

作者： LIU Hong-hui, YANG Xiao-huan, WANG Nai-bin, LIU Hai-yan (Center for resources and Environmental Data, institute of geographic sciences and natural resources Research, Chinese Academy of sciences, Beijing 100101, China)

Global change research and sustainable development need to be addressed at larger scales in the light of small scale process studies. Much remains to be done before the small scale, process level understanding of ecosystem responses to global change can be reliably translated to larger scales. The paper reviews the status of scaling issues and tries to find how to extrapolate our observations and our findings at site scale up to regional scale and provide ecological information and interpretations at the regional scale. An integrated approach to scaling-up from site to region is proposed combining hierarchical theory, landscape ecology, remote sensing, geographical information system (GIS) with process/mechanistic modeling. Remote sensing and GIS will play key roles in spatial analysis, integration as well as cross scale modeling.

关键词： scale issue global change study scaling up integrated approach

Environmental emigration stress of slope farmland in the Three Gorges area

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Journal of geographical sciences 2002年第4期12卷 420-426页

作者： WANG Liming, GUAN Qingfeng, YANG Yanfeng(Inst. of geographic sciences and natural resources Research, CAS, Beijing 100101, China) Inst. of geographic sciences and natural resources Research CAS 北京 100101

The project of ‘grain for green’, to restore woodland and grass by retreating from slope farmland, as a fundamental measure of eco-environmental rehabilitation, is being conducted in the reservoir area of the Three Gorges gradually. However, the de-farming of slope farmland will reduce the amount of farmland in de-farmed areas, especially in the areas with concentrated slope farmland, which would cause the problems of environmental emigration. The people who cannot regain enough farmland by relocating farmlands within village after de-farming and have to emigrate to other places are called environmental emigrants or ecological emigrants. In the research, a de-farming stress index model and an environmental emigration model are developed based on GRID data, and the potential amount of environmental emigration caused by de-farming of slope farmland in the reservoir area is simulated aided with GIS. The simulation indicates that the potential emigration amount caused by de-farming is quite large. When the de-farming stress index reaches 40%, the amount is as large as 890,000 people, which is equivalent to the emigrants caused by the submergence of the Three Gorges reservoir. So it should be considered as a big problem during the eco-environmental rehabilitation in this area. Some suggestions are raised to tackle the problem. Firstly, the emigration plan should be included in the de-farming plan. Secondly, some provinces, especially those located in the lower reaches of the Yangtze River, should accommodate part of the environmental emigrants.

关键词： environmental emigration slope farmland de-farming Three Gorges

Diversity and geographical Pattern of Altitudinal Belts in the Hengduan Mountains in China

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Journal of Mountain science 2010年第2期7卷 123-132页

作者： YAO Yonghui ZHANG Baiping HAN Fang, PANG Yu institute of geographic sciences and natural resources Research Chinese Academy of Sciences Beo'ing 100101 China.

This paper analyses the diversity and spatial pattern of the altitudinal belts in the Hengduan Mountains in China. A total of 7 types of base belts and 26 types of altitudinal belts are identified in the study region. The main altitudinal belt lines, such as forest line, the upper limit of dark coniferous forest and snow line, have similar latitudinal and longitudinal spatial patterns, namely, arched quadratic curve model with latitudes and concave quadratic curve model along longitudinal direction. These patterns can be together ealled as ＂Hyperbolic-paraboloid model＂, revealing the complexity and speciality of the environment and ecology in the study region. This result further validates the hypnosis of a common quadratic model for spatial pattern of mountain altitudinal belts proposed by the authors. The spatial pattern of altitudinal belts is closely related with moisture-related exposure effect in the Hengduan Mountains. Different combinations （spectra） of altitudinal belts and different base belt types appear in windward and leeward flanks and even in the same flanks of different ranges. This is closely related with the parallel mountain ranges of the Hengduan Mountains, which, at nearly right angle with the moving direction of prevailing moisture-laden air masses from west and east, hold up the warm and humid monsoon wind from moving into the core region and result in different moisture conditions in windward and leeward flanks. However, how to quantitatively describe the moisture-related exposure effect needs further study. In addition, the data quality and data accuracy at present also affect to some extent the result of quantitative modeling and should be improved with RS/GIS in the future.

关键词： Hengduan Mountains Altitudinal belt spectra Exposure effect Quadratic model

Current situation and trend of arable land change in China

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Journal of geographical sciences 2000年第3期10卷 28-34页

作者： Received date: 1999-11-02 MENG Xiang-jing1 , JIA Shao-feng 2 (1.institute of Population Research, People’s University of China, Beijing 100872, China 2. institute of geographic sciences and natural resources Research, Chinese Academy of sciences, Beiji 中国人民大学北京中科院地理科学与资源所北京

How to protect arable land in the process of economic development and urbanization is a critical issue in China. In this paper, an attempt is made to analyze the situation of arable land change in China and it's relationship with population growth, economic development and urbanization. In depth analysis is also made in different regions. Forecasting is conducted to show the trend of arable land change in China based on the results of correlation analysis. Some suggestions are put forward for the policy making of reasonable utilization and protection of arable land in the future.

关键词： arable land change population growth economic development urbanization

Edaphic factors determining variation of two ecotypes of Leymus chinensis in North China

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Progress in natural science:Materials International 2006年第11期16卷 1150-1155页

作者： ZHOU Chan~1 and YANG Yunfei~2**(1. MOE Key Laboratory of Environmental Change and natural Disasters, College of resources science and Technology, Beijing Normal University, Beijing 100875, China 2. Key Laboratory of Vegetation Ecology, Ministry of Education, institute of Grassland science, Northeast Normal University, Changchun 130024, China) [a]MOE Key Laboratory of Environmental Change and natural Disasters College of Resources Science and Technology Beijing Normal University Beijing China [b]Key Laboratory of Vegetation Ecology Ministry of Education Institute of Grassland Science Northeast Normal University Changchun China

To identify ecotypic variation of L. chinensis, the physiological characteristics and environmental factors were measured and assessed for grey-green and yellow-green ecotypes of L. chinensis grown in the salt-alkalized and aeolian sandy soils. Although both ecotypes presented a similar salt-alkaline tolerance under the experimental conditions, they differed in several aspects. The L. chinensis grown in the aeolian sandy soils had higher water potential and chlorophyll content and lower proline content in their leaves than those grown in the salt-alkalized habitat, and the grey-green ecotype of L. chinensis in both types of soils had higher water potential, chlorophyll and proline contents than the yellow-green ecotype. Besides, grey-green ecotypes had higher salt-alkaline tolerance than the yellow-green ecotype. The stepwise regression analysis showed that soil conductance and pH value were the main ecological factors affecting the physiology of L. chinensis. From the natural distribution of the two ecotypes, we considered that salt-alkaline in the soils is the leading factor in determining ecotypic variation of L. chinensis. The two ecotypes were first named grey-green and yellow-green ecotypes respectively.

关键词： L.chinensis ecotype adaptability variation ecological factor salt-alkaline in soil.

China's Regional Policies:Progress of the 11^(th) Five Year Plan Period and Prospect of the 12^(th) Five Year Plan Period

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Chinese Journal of Population,resources and Environment 2011年第2期9卷 90-96页

作者： Chen Xuebin1,2 1.institute of geographic sciences and natural resources Research,Chinese Academy of sciences,Beijing 100101,China 2.National Development and Reform Commission,Beijing 100824,China institute of geographic sciences and natural resources Research Chinese Academy of Sciences Beijing 100101 China National Development and Reform Commission Beijing 100824 China

During the 11th Five Year Plan period,China improved its policy system for the overall strategy of regional development,and established and completed the policies intended for the promotion of regional cooperation and ***,regional development in China took on a series of positive changes such as the enhancement of *** the 12th Five Year Plan period,China will fully implement and continuously improve the policy measures for development in its four major regions,strengthen differentiated guidance to different regions in line with the planning for major function-oriented zones,and accelerate the establishment of basic systems that facilitate coordinated regional development.

关键词： regional policy progress prospect

Vegetation and soil carbon storage in China

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science China Earth sciences 2004年第1期47卷 49-57页

作者： LI Kerang, WANG Shaoqiang & CAO Mingkuiinstitute of geographic sciences and natural resources Research, Chinese Academy of sciences, Beijing 100101, China Department of Geography, Maryland University, College Park,MD 20742, USA Correspondence should be addressed to Li Kerang Inst. of Geogr. Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China Department of Geography Maryland University College Park MD 20742 United States

This study estimated the current vegetation and soil carbon storage in China using a biogeochemical model driven with climate, soil and vegetation data at 0.5°latitude-longitude grid spatial resolution. The results indicate that the total carbon storage in China's vegetation and soils was 13.33 Gt C and 82.65 Gt C respectively, about 3% and 4% of the global total. The nationally mean vegetation and soil carbon densities were 1.47 kg C/m2 and 9.17 kg C/m2, respectively, differing greatly in various regions affected by climate, vegetation, and soil types. They were generally higher in the warm and wet Southeast China and Southwest China than in the arid Northwest China; whereas vegetation carbon density was the highest in the warm Southeast China and Southwest China, soil carbon density was the highest in the cold Northeast China and southeastern fringe of the Qinghai-Tibetan Plateau. These spatial patterns are clearly correlated with variations in the climate that regulates plant growth and soil organic matter decomposition, and show that vegetation and soil carbon densities are controlled by different climatic factors.

关键词： carbon storage, vegetation, soil, China.

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CONTINUOUS L-DOMAINS

Chinese Annals of Mathematics,Series B 1996年第3期17卷 263-270页

作者： LIANG JIHUA LIU YINGMING(institute of Mathematics, Sichuan University, Chengdu 610064, China.)(Project supported by the National natural science Foundation of China.) SICHUAN UNIV INST MATHCHENGDU 610064PEOPLES R CHINA

Two characterization theorems of continuous L-domain are given. Then a problem raisedby J. D. Lawson and M. Mislove is solved.

关键词： L-domain Continuous DCPO Domain theory