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Impact of land-use change on hydrological processes in the Maying River basin, china

Science china Earth sciences 2006年第10期49卷 1098-1110页

作者： WANG Genxu1,3, ZHANG Yu2. LIU Guimin2.& CHEN Lin3 1. Institute of Mountain Hazards and Environment, chinese academy of {2., Chengdu 610041, china 2. Cold and Arid Regions Environmental and Engineering Research Institute, chinese academy of {2., Lanzhou 730000, china 3. Resource and Environment School, Lanzhou university, Lanzhou 730000, china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Resource and Environment School Lanzhou University Lanzhou China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Since the 1960s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of china. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest china, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1965. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1967, has resulted in a mean annual runoff decrease of 2..12., a base flow decline of 35.32., a drop in the maximum peak discharge of 35.77%, and mean discharge decreases in spring and autumn of 36.05% and 2..87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73%-81%, and that to the influence of base flow reaching 62.-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying River.

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Architecture and application of integrated spatial information service platform for digital mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 706-711页

作者： ZHANG Jin1, XIAO Jie2.1. College of Mining, Taiyuan university of Technology, Taiyuan 03002., china 2. Institute of Geodesy and Geophysics, {2. academy of sciences, Wuhan 430077, china College of Mining Taiyuan University of Technology Taiyuan 030024 China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China

Using enterprise GIS platform, spatial databases and modern information technology, building geo-spatial information service platform of digital mine which has the features of the data exchange service, enterprise GIS services, directory services, logging services, is key technology and application infrastructure for digital mine. Based on the support of geospatial information service platform of digital mine, the professional GIS application service adapter can be developed and the application supports related to mining application system can be realized. Using high-resolution satellite remote sensing data, the mine functional partition map and geographic grids can be divided, and the geographic grid parts, status and events of important features of the surface object were investigated and defined. The system architecture and technical characteristics of integrated spatial information service platform were analyzed firstly, which guarantee service ability of digital mine. The methods and applications of functional partition map for integrated management service platform were discussed which are the services scheme of digital mine. The application results indicated that digital mine upgrades and enhances the capability and range of mine surveying and mapping, and is of great significance for guarantee of efficient, green and intensive exploitation of mine.

关键词： platform architecture web services application services digital mine

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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 Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, chinese academy of {2., Beijing 10002., china 2. Department of Atmospheric {2., Yunnan university, Kunming 650091, china 3. china Meteorological Administration Training Centre, Beijing 100081, china 4. Graduate School of chinese academy of {2., Beijing {12., china State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric sciences Yunnan University Kunming China Graduate School of chinese academy of {2. Beijing China china Meteorological Administration Training Centre Beijing 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 Indo{2. 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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Relative importance of water, energy, and heterogeneity in determining regional pteridophyte and seed plant richness in china

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Journal of Systematics and Evolution 2011年第2期49卷 95-107页

作者： 1,2.3 Sheng-Bin CHEN § 1 Gao-Ming JIANG 3 Zhi-Yun OUYANG 3 Wei-Hua XU 3 Yi XIAO 1 (State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, chinese academy of {2., Beijing 100093, china) 2.(Graduate university of the chinese academy of {2., Beijing 100049, china) 3 (State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental {2., chinese academy of {2., Beijing 100085, china) (State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate university of the chinese {2. of sciences Beijing 100049 China) (State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China)

Environmental variables, such as ambient energy, water availability, and environmental heterogeneity have been frequently proposed to account for species diversity gradients. How taxon-specific functional traits define large-scale richness gradients is a fundamental issue in understanding spatial patterns of species diversity, but has not been well documented. Using a large dataset on the regional flora from china, we examine the contrast spatial patterns and environmental determinants between pteridophytes and seed plants which differ in dispersal capacity and environmental requirements. Pteridophyte richness shows more pronounced spatial variation and stronger environmental associations than seed plant richness. Water availability generally accounts for more spatial variance in species richness of pteridophytes and seed plants than energy and heterogeneity do, especially for pteridophytes which have high dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a higher proportion of pteridophytes in regional vascular plant floras (pteridophyte proportion) in wet regions. Most of the variance in seed plant richness, pteridophyte richness, and pteridophyte proportion explained by energy is included in variation that water and heterogeneity account for, indicating the redundancy of energy in the study extent. However, heterogeneity is more important for determining seed plant distributions. Pteridophyte and seed plant richness is strongly correlated, even after the environmental effects have been removed, implying functional linkages between them. Our study highlights the importance of incorporating biological traits of different taxonomic groups into the studies of macroecology and global change biology.

关键词： habitat heterogeneity pteridophytes seed plants species richness water-energy hypothesis.

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A revision of Clematis ***(Ranunculaceae)

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Journal of Systematics and Evolution 2009年第6期47卷 552-580页

作者： ~(1,2.Wen-Jing YANG ~1Liang-Qian LI~* ~3Lei XIE 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of {2.,Beijing 100093,china) 2.Graduate university of chinese academy of {2.,Beijing 100049,china) 3(Southwestern china Germplasm Bank of Wild Species,Kunming Institute of Botany chinese academy of {2. Kunming 6502.4,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate university of chinese {2. of sciences Beijing 100049 China) (Southwestern china Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China)

Clematis *** is revised in this paper based on the examination of a large number of herbarium specimens,extensive field observations,and morphometric *** taxonomic history and geographical distribution of the section are given,the relationships among the species are discussed,and the evolutionary trends of some characters in the section are *** staminodes of the plants in this section may have evolved from the outer stamens with petaloid filaments and gradually disappearing ***,they may have evolved in two different *** possibility is that the staminodes elongate and become lanceolate,as long as sepals,and their apices turn into *** other is that the staminodes are spathulate,but not elongating,as long as stamens,and their apices turn into retuse from obtuse and *** evolutionary trend of sepals may be from thin to thick in texture,and the veins from non-prominent to *** a result,five new series are established and nine species, two subspecies and nine varieties(including three new ranks) are recognized in this *** identification key is provided,and each taxon is described and *** sibirica and Clematis ochotensis are treated as subspecies of Clematis alpina due to their subtle differences and lack of,or few,overlapping *** fusijamana and Clematisfauriei are recognized as varieties of *** *** for the continuous variation of the velutinous strips on the sepal *** iliensis is treated as variety of *** *** for the continuous variation of leaf division *** variations in sepal color and basal caruncle size support degrading Clematis chiisanensis as a variety of Clematis *** North American *** may be primitive,whereas *** may be the most advanced taxon in this *** and *** are closely related to each ***,the systematic position of se

关键词： Clematis sect.Atragene Ranunculaceae taxonomic revision

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Birthrates and delay times of Type Ia supernovae

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Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 586-590页

作者： WANG Bo1,2.3, LIU ZhengWei1,2.3, HAN YunKun1,2.3, LEI ZhenXin1,2.3, LUO YangPing1,2.3 & HAN ZhanWen1,2.1National Astronomical Observatories/Yunnan Observatory, chinese academy of {2., Kunming 650011, china 2.ey Laboratory for the Structure and Evolution of Celestial Objects, chinese academy of {2., Kunming 650011, china 3Graduate university of chinese academy of {2., Beijing 100049, china National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming China Graduate university of chinese {2. of sciences Beijing China

Type Ia supernovae (SNe Ia) play an important role in diverse areas of astrophysics, from the chemical evolution of galaxies to observational cosmology. However, the nature of the progenitors of SNe Ia is still unclear. In this paper, according to a detailed binary population synthesis study, we obtained SN Ia birthrates and delay times from different progenitor models, and compared them with observations. We find that the Galactic SN Ia birthrate from the double-degenerate (DD) model is close to those inferred from observations, while the birthrate from the single-degenerate (SD) model accounts for only about 1/2.2.3 of the observations. If a single starburst is assumed, the distribution of the delay times of SNe Ia from the SD model is a weak bimodality, where the WD + He channel contributes to the SNe Ia with delay times shorter than 100 Myr, and the WD + MS and WD + RG channels to those with age longer than 1 Gyr.

关键词： binaries: close stars: evolution supernovae: general white dwarfs

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Effective solutions to a global 3D visual system in networking environments

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Science china Earth sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2. ZHANG Yan3, YANG Chongjun2. LIU Suhong1, REN Yingchao2. RUI Xiaoping2.& LIU Donglin2.1. State Key Laboratory of Remote Sensing sciences, School of Geography and Remote Sensing, Beijing Normal university, Beijing 100875,{2. 2. State Key Laboratory of Remote Sensing sciences, Institute of Remote Sensing Applications, chinese academy of sciences, Beijing 101001,{2. 3. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, Beijing 101001,{2. State Key Laboratory of Remote Sensing sciences School of Geography and Remote Sensing Beijing Normal University Beijing China chinese academy of {2. State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications China Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences China

The development of Web-based global 3D visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

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Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

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Progress in Natural Science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2.and Luo Zhexian2.1. Institute of Atmospheric Physics, chinese academy of {2., Beijing 10002., china 2. Nanjing university of Information {2. & Technology, Nanjing 2.0044, china) Institute of Atmospheric Physics Chinese Acad. of Sci. Beijing 100029 China Nanjing university of Information sciences and Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 12.0 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation

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Analysis and Modeling on the Spatial Structure of Urban Land Use: A Case of Jinan, china

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chinese Journal of Population,Resources and Environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1, 3, Zhang Zulu2. Jiang Luguang 1 1. Institute of Geographical sciences and Natural Resources Research, chinese {2. of sciences, Beijing 100101, china 2. College of Population, Resources and Environment, Shandong Normal university, Jinan Shandong 2.0014, china 3. Graduate School of the chinese {2. of sciences, Beijing 100039, china Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the chinese academy of {2. Beijing 100039 China College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1986 and 2.04, the spatial structure of Jinan is studied in this paper with the method of Geographic Information System (GIS). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 50%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1986 to 2.04, great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure Jinan

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Monitoring of rice crop using ENVISAT ASAR data

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Science china Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2. SUN Guoqing1,3 & PANG Yong4 1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, chinese academy of {2., Beijing 100101, china 2. Graduate university of chinese academy of {2., Beijing 100039, china 3. Department of Geography, university of Maryland, College Park, MD 2.742. USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information Technology, chinese academy of For-estry, Beijing 100091, china State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China Graduate university of chinese {2. of sciences Beijing China Department of Geography University of Maryland College Park USA Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

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