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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 {2. and Natural Resources Research, Chinese Academy of {2., Beijing 100101, China 2. Graduate {3. of the Chinese Academy of {2., Beijing 10003., China 3. College of Arts and {2. of Beijing Union University, Beijing 100083. China 4. school of forestry and wildlife sciences,{12. University,{12., alabama, al3.849, USA 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate school of the Chinese Academy of sciences 100039 Beijing China 3. school of {2. and {2. {3. Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of Beijing Union University 100083 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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Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2. 3. ZHANG Jin4.1. Institute of Geodesy and Geophysics, Chinese Academy of {2., Wuhan 4.0077, China 2. Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, Chinese Academy of {2., Wuhan 4.0077, China 3. Graduate {2. of Chinese Academy of {2., Beijing 10004., China 4. Department of Surveying and Mapping, Taiyuan University of Technology, Taiyuan 03.02.1} China Taiyuan Univ Technol Dept Surveying & Mapping Taiyuan 030024 Peoples R China Chinese Acad Sci Inst Geodesy & Geophys Key Lab Dynam Geodesy Wuhan 430077 Peoples R China Chinese Acad Sci Grad Sch Beijing 100049 Peoples R China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

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Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1,2. LI Anchun1, HU Ningjing2.3. FU Yongtao1& MA Zhibang4.1. Institute of Oceanology, Chinese Academy of {2., Qingdao 2.6071, China 2. Graduate school of the Chinese Academy of {2., Beijing 10003., China 3. Institute of Soil Science, Chinese Academy of {2., Nanjing 2.0008, China 4. Institute of Geology and Geophysics, Chinese Academy of {2., Beijing 10002., China 1. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate school of the Chinese Academy of sciences Beijing 100039 China 3. Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China 4. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

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Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural {2. 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2.3., LI Xiao-wei 2.3.. {2. of Information Engineering, Zhejiang forestry College, Hangzhou 3.13.0, Zhejiang, China 2. Institute of Computing Technology, Chinese Academy of {2., Beijing 100080, China 3. Graduate {2. of the Chinese Academy of {2., Beijing 10003., China school of Information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

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The onset and advance of the Asian summer monsoon

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Science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2.4. ZHANG Qingyun1, TAO Shiyan1 & JU Jianhua3.1. State Key Laboratory of Numeric{2. Modeling for Atmospheric Sci- ences and Geophysic{2. Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 10002., China 2. Department of Atmospheric sciences, Yunnan University, Kunming 650091, China 3. China Meteorologic{2. Administration Training Centre, Beijing 100081, China 4. Graduate {2. of Chinese Academy of sciences, Beijing 10003., China State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric sciences Yunnan University Kunming 650091 China Graduate school of Chinese Academy of sciences Beijing 100039 China China Meteorological Administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from National Oceanic and At- mospheric Administration (NOAA) satellites, the Cli- mate Prediction Center’s merged analysis of pre- cipitation (CMAP) data and the National Centers for Environmental Prediction/National Center for At- mospheric Research (NCEP/NCAR) reanalysis dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum analysis, band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- china Peninsula, the east coast of Bay of Bengal, the South China Sea and the Indian subcontinent are explored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indochina Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2.d pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.

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Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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Science China Earth sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2. WANG Qingfei1,2., HUANG Dinghua3., WAN Li4. YANG Liqiang1,2.& GAO Bangfei1,2.1. State Key Laboratory of Geologic{2. Processes and Miner{2. Resources, China University of Geosciences, Beijing 100083. China 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, China University of Geo- sciences, Beijing 100083. China 3. Faculty of Earth sciences, China University of Geosciences, Wuhan 4.0074. China 4. {4. of Mathematics and Information Science, Guangzhou University, Guangzhou 5104.5, China 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China 3. Faculty of Earth sciences China University of Geosciences Wuhan 430074 China 4. school of Mathematics and Information Science Guangzhou University Guangzhou 510405 China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

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Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1,2. , XIANG Jianhai 1*, WANG Bing 1,2. , LI Fuhua 1 and TONG Wei 3.1. Experimental Marine Biology Laboratory, Institute of Oceanology, Chinese Academy of {2., Qingdao 2.6071,China 2. Graduate school of the Chinese Academy of {2., Beijing 10003., China 3. Genomics & Bioinformatics Institute, Chinese Academy of {2., Beijing 1013.0, China) Chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China Chinese Acad Sci Grad Sch Beijing 100039 Peoples R China Chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 104.6 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4. of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors

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Construction of nonbinary quantum cyclic codes by using graph method

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Science in China(Series F) 2005年第6期48卷 693-702页

作者： LIU Tailin1,2.3. WEN Qiaoyan1 & LIU Zihui4.1. {2. of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China 2. State Key Laboratory of Integrated Services Network, Xidian University, Xi’an 710071,China 3. Shandong Finance Institute, Jinan 2.0014. China 4. {2. of Mathematical {2., Peking University, Beijing 100871, China 1. school of Science Beijing University of Posts and Telecommunications 100876 Beijing China 2. State Key Laboratory of Integrated Services Network Xidian University 710071 Xi’an China 3. Shandong Finance Institute 250014 Jinan China 4. school of Mathematic{2. sciences Peking University 100871 Beijing China

Using the graph method proposed by Schlingemann and Werner, this paper introduces a technique to construct nonbinary quantum cyclic codes and provides a specific example. We also construct the quantum codes [[8, 2. 4.... 详细信息

关键词： nonbinary quantum stabilizer codes quantum cyclic codes

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science China Earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2. CAI Qiangguo1, YUE Zhongqi3. LU Zhongchen4. LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic {2. and Natural Resources Re-search, Chinese Academy of {2., Beijing 100101, China 2. Institute of {3., Chinese Academy of {3. {2., Beijing 100091, China 3. Department of Civil Engineering, University of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, Chinese Academy of {2., Beijing 100085, China 5. College of Resources and Environment, Southwest Agricultural University, Chongqing 4.0716, China Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 53. mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4. less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 3.%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science China Earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3. ZHANG Yili1, BAI Wanqi1, LIU Yanhua4. BAO Weikai5, LIU Linshan1, 2.& ZHENG Du1 1. Institute of Geographic {2. and Natural Resources Research, Chinese Academy of {2., Beijing 100101, China 2. Graduate {3. of the Chinese Academy of {2., Beijing 10003., China 3. College of Resources and Environment, Southwest Agricultural University, Chongqing 4.0716, China 4. The Ministry of Science and Technology, P. C. China, Beijing 100862. China 5. Chengdu Institute of Biology, Chinese Academy of {2., Chengdu 61004., China 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate school of the Chinese Academy of sciences 100039 Beijing China 3. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and Technology P. C. China 100862 Beijing China 5. Chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.4.%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

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