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Spatial heterogeneity of the driving forces of cropland change in China

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 Natural 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 Natural 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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Sandy desertification trend in western Northeast China Plain in the past 10 years

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Journal of Geographical Sciences 2001年第2期11卷 179-186页

作者： LI Bao-lin~1,2. ZHOU Cheng-hu~1 (1. LREIS, institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China 2. institute of Remote Sensing Application, CAS, Beijing 100101, China) institute of Remote Sensing Application CAS LREIS Institute of Geographic Sciences and Natural Resources Research CAS LREIS Institute of Geographic Sciences and Natural Resources Research CAS

The west sandy land of the Northeast China Plain is located in the eastern huge sandy belt of mid-latitude in Eurasia and the eastern fringe of desertified land with best bio-climatic conditions in China. With rapid economic development, the deterioration of eco-environment has occurred and the desertification becomes very obvious. The first part of this paper studies the regional differences of landscape patterns and explores the regional differences of desertification. The second part aims to reveal the dynamics of desertification in the 1990s by using NOAA/AVHRR data and thematic data in GIS database. This work lays a scientific basis for the rehabilitation and development of the sandy lands.

关键词： west sandy land in Northeast China Plain landscape pattern regional difference remote sensing monitoring dynamic change

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Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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Chinese Science Bulletin 2012年第35期57卷 4617-4626页

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National Center for Atmospheric Research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模

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Digital image analysis of palaeoenvironmental records and applications

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Chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2. LIU Yu2.& TAN Ming31. South China Sea institute of Oceanology, Chinese Academy of Sciences. Guangzhou 510301, China 2. State Key Laboratory of Loess and Quaternary Geology, Earth Environmental institute, Chinese Academy of Sciences, Xi’an 710075, China 3. institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China South China Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key Laboratory of Loess and Quaternary Geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

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Influence of MB-value of Manufactured Sand on the Shrinkage and Cracking of High Strength Concrete

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 321-325页

作者：王稷良 Key Laboratory of Road Structure and Material Ministry of Communications (Beijing) Research Institute of Highway Ministry of Communication

The relation between methylene blue （MB） value of MS and its limestone dust content and clay content was investigated. The effects of MB value ranging from 0.35 to 2.5 on the workability of fresh concrete and crack propagation characteristics at the age of 2. hours, and effects on the mechanical properties, dry shrinkage of the harden concrete were tested. The experimental results show that the MB value is not related with the limestone dust content of MS, but in direct proportion to clay content. With the increase of MB value, the concrete workability decreases, and the flexural strength and 7 d compressive strength reduce markedly, whearas the 2. d compressive strength is not affected. When the MB-value is less than or equal to 1.35, the change of the MB-value has a little influence on early plastic cracking and dry shrinkage property of concrete, but when the MB-value is more than 1.35, the tendency of plastic cracking and dry shrinkage is remarkable.

关键词： manufactured sand methylene blue value high strength concrete anti-cracking shrinkage

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An analysis on the evolvement processes of lake eutrophication and their characteristics of the typical lakes in the middle and lower reaches of Yangtze River

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Chinese Science Bulletin 2006年第13期51卷 1603-1613页

作者： CHENG Xiaoying1,2.3 & LI Shijie1 1. Nanjing institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 2.0008, China 2. The Key Laboratory of Industrial Biotechnology, Ministry of Educa- tion, Southern Yangtze University, Wuxi 2.4036, China 3. School of Biotechnology, Southern Yangtze University, Wuxi 2.4036, China Nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing China The Key Laboratory of Industrial Biotechnology Ministry of Education Southern Yangtze University Wuxi China School of Biotechnology Southern Yangtze University Wuxi China

According to the study on the aquatic environment of the typical lakes in the middle and lower reaches of Yangtze River, lake eutrophication is a process in which the lake ecosystem degenerates, resulting in the deterioration of the water quality due to the enrichment of the nutrients. Moreover, the succession of lake ecosystem and change of water quality both couple well with the evolvement of tro- phic state. Then the conceptual model is mentioned and ten lake states are classified. Based on these, the authors analyzed the eutrophication processes of the typical lakes in the middle and lower reaches of Yangtze River. The large lakes with taking in - send- ing out water typical of Poyang Lake evolve from State 1 before the 1980s into State 2.after the 1980s, the large and medium lakes typical of Taihu Lake evolve from State 1-2.in the 1960s into State 8 in the 1980s then into State 9 in the 1990s, the medium and small shallow lakes typical of Honghu Lake evolve from State 1 in the 1960s into State 2.after the 1980s and the small city (suburban) lakes typical of Donghu Lake evolve from State 2.in the 1960s into State 9 after the 1970s. Further, the 1980s is the key con- version period of the lakes of various types typical of Poyang Lake, Honghu Lake and Taihu Lake con- verting into mesotrophic state, the 1990s is that of Taihu Lake into eutrophic state and the 1970s is thatof the small city (suburban) lakes typical of Donghu Lake into eutrophic state. The series of nutrient evolvement of different typical lakes are similar, but the processes are not synchronous, which is related to the various human and natural driving mechanisms in lake basins.

关键词：长江湖泊富营养化概念模型转变时期驱动机制

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Impact of the closure of Indonesian seaway on climate: A numerical modeling study

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Chinese Science Bulletin 2003年第S2期48卷 88-93页

作者： YU Yongqiang, ZHOU Zuyi & ZHANG Xuehong 1. LASG, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., China: 2. Laboratory of Marine Geology, Tongji University, Shanghai 2.0092.China Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100029 Peoples R China Tongji Univ Lab Marine Geol Shanghai 200092 Peoples R China

Using a global OGCM and its relevant coupledocean-atmosphere GCM with the contemporary, 6 MaBPand 14 MaBP oceanic topography, respectively, a series ofnumerical experiments are implemented in order to investi-gate the effect of the north shift of Australian continent onthe tropical oceanic circulation, especially the formation ofthe western Pacific warm pool. The numerical experimentsof the individual OGCM forced by the modern atmosphericcirculation indicate that the closure of Indonesian passageresults in warming in the tropical Pacific Ocean and coolingin the tropical Indian Ocean; furthermore, it also results inchange in source of the Indonesian Through Flow (ITF) wa-ter, e.g. ITF mainly originates from the south Pacific at 14MaBP, but it mainly originates from the north Pacific *** coupled model shows similar results as the individualOGCM qualitatively.

关键词： Indonesian Through Flow (ITF) Western Pacific Warm Pool Australian Plate Paleo-oceanography.

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Arable land increase in northern China: facts and findings

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Journal of Geographical Sciences 2002年第1期12卷 108-113页

作者： SONG Jin-ping1, LI Xiu-zhen2.(1. Dept. of Resources and Environment, Beijing Normal University, Beijing 100875, China 2. institute of Applied Ecology, CAS, Shenyang 110015, China) Dept. of Resources and Environment Beijing Nonnal University 北京 100875 institute of Applied Ecology CAS Shenyang 110015

Based on investigations between 1986 and 1996 in the four provinces of northern China, major problems on land reclamation were discovered. The increase of arable land was mainly low quality fields from barren land and was susceptible to disertification and water-induced soil erosion. In the meantime, large area of grassland and forestland was lost or degraded, and original fertile arable land was occupied for residential and industrial use. As a result the environment deteriorated. This change was mainly caused by economic development, population growth, inferior natural conditions, and irrational management strategies. Finally some positive measures were suggested to stop this negative cycle.

关键词： arable land reclamation land resources land quality

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Dynamical framework with blocking topography coordinates for atmospheric GCM and its validation

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Chinese Science Bulletin 2003年第S2期48卷 9-17页

作者： LIN Zhaohui~1, ZHANG Ming~(1,2., LIANG Danqing~(1,2. WANG Aihui~1, ZHANG Dongling~1 & ZENG Qingcun~1 1. ICCES, institute of Atmospheric Physics, Chinese Academy of Sciences. Beijing 10002.. China 2. College of meteorology. PLA University of Science and Technology, Nanjing 2.1101. China Chinese Acad Sci Inst Atmospher Phys ICCES Beijing 100029 Peoples R China PLA Univ Sci & Technol Coll Meteor PLA Nanjing 211101 Peoples R China

The dynamical framework with Blocking To-pography Coordinates (hereafter, BTC), which is suited tohandle the steep topography for the atmospheric generalcirculation models, is presented in this paper, together withits validation results. The integral properties of both the dif-ferential and finite-difference equations for the BTC dy-namical core are: gross mass conservation, quadratic con-servation for advection terms, Coriolis force does not changethe kinetic energy, conservation of total available energy. Theimproved nonlinear iteration scheme is utilized for thetime-integration. The energy conservation for BTC dynami-cal core is validated by using the integration results from9-layer and 2.-layer version respectively. Comparison resultsshow that, the changes of the kinetic energy and total avail-able potential energy during the integration are quite closefor both the BTC dynamical framework and the dynamicalframework of IAP 9-level and IAP 2.-level AGCM, and thismay suggest that the BTC dynamical core can be used forlong-term integration with good computational ***, the BTC dynamical core has the advantageover the terrain following (sigma) coordinates in its betterrepresentation of the influence of the large-scale topographyon the atmospheric general circulation. Finally, the correct-ness and reasonableness of the BTC dynamical core has beenfurther proved by the numerical simulation of the topogra-phy influence on the quasi-stationary planetary wave with2.-layer version of BTC dynamical framework.

关键词： blocking topography coordinates atmospheric general circulation model dynamical framework.

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Immunization with autologous T cells enhances in vivo anti-tumor immune responses accompanied by up-regulation of GADD45β

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Cell Research 2006年第8期16卷 702-712页

作者： Li Wang~(1,2.*) Fang Du~(1,2.*) Qi Cao~(1,2. Huiming Sheng~(1,2. Baihua Shen~(1,2. Yan Zhang~(1,2. Yingna Diao~(1,2. Jingwu Zhang~(1,2. Ningli Li~(1,2. ~1Shanghai diao Tong UniversiO,School of medicine,2.0 Chongqing Road,Shanghai 2.002.,China ~2.hanghai institute of Immunology,2.0 Chongqing Road,Shanghai 2.002.,China Shanghai Jiao Tong University School of medicine Shanghai China Shanghai institute of Immunology Shanghai China

Immunization with inactivated autoreactive T cells may induce idiotype anti-idiotypic reactions to deplete autoreac-tire T cells,which are involved in autoimmune ***,it is unknown whether attenuated activated healthyautologous T-cell immunization could increase anti-tumor immune *** this end,C57B1/6 mice were immunizedwith attenuated activated autologous T *** splenocytes from immunized mice showed a higher proliferative abil-ity than that from naive *** special phenotype analysis showed that there were more CDS+T cells and CD62.+T cells in immunized mice after 2. h of culture with 10% fetal calf serum complete medium in vitro(Pmeasured by real-time *** results indicated that GADD45β transcription was higher in the splenocytes fromimmunized mice than that in the naive *** addition,the Fas expression showed a parallel higher,but FasL did notchange *** investigate the biologic functions induced by immunization in vivo,a tumor model was establishedby EL-4 tumor cell inoculation in C57/B1 *** receiving autologous T-cell immunization had significantly inhibitedtumor growth in vivo(P<0.01).This study implicated that immunization with attenuated activated autologous T cellsenhances anti-tumor immune responses that participate in tumor growth inhibition.

关键词： anti-tumor immunity immunization autologous T cells GADD45β AICD

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