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Assessment of soil erosion and sediment delivery ratio using remote sensing and GIS:a case study of upstream Chaobaihe River catchment, north china

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International Journal of Sediment Research 2008年第2期23卷 167-173页

作者： Weifeng ZHOU1 and Bingfang WU2.1 Doctor candidate,graduate school of the {2. academy of sciences(CAS),beijing 10003.,china 2.Prof.,Institute of Remote Sensing Applications,{2. academy of sciences(CAS),beijing 100101,china Doctor candidate Graduate School of the Chinese Academy of Sciences(CAS) Beijing 100039 China Prof. Institute of Remote Sensing Applications Chinese Academy of Sciences(CAS) Beijing 100101 China

Soil erosion in catchment areas reduces soil productivity and causes a loss of reservoir *** parametric models have been developed to predict soil erosion at drainage basins,hill slopes and field *** well-known Universal Soil Loss Equation(USLE) represents a standardized *** reservoir,which sits on Chaobaihe River,is the main surface source of drinking water for beijing,the capital of *** and soil loss are the main reasons for sediment to enter a *** yield is assessed using a version of the universal soil loss equation modified by chinese *** year 2.01 and 2.02.data for factors in the equation are obtained from remote sensing or collected to form an analysis *** factors are computed and mapped using Geographic Information System *** on the complex database,the modified model is *** pixel-based computing the sediment yield per hydrological unit is *** model does not consider sediment deposition occurring on *** soil loss is often higher than the sum of those measured at catchment *** sediment delivery ratio(SDR) per hydrological unit is also *** study analyzes the main contributions of sediment yields on sub-basins of the Chaobaihe River to the Miyun Reservoir,and discusses the possible reasons for the difference between SDRs in 2.01 and 2.02.at different *** result shows that in the upper basin of the Miyun Reservoir,in 2.01 the area of erosion that could be neglected was 8,2.2.76 km2.the area of low erosion 3,2.9.59 km2.the area of moderate erosion 3,400.97 km2.the area of high erosion 436.89 km2.the area of strong erosion 52.19 km2.and the area of severe erosion 3.13 *** highest soil loss was 70,353 t/*** in Fengning County in 2.01,followed by 64,418 t/*** by Chicheng County in *** SDR in 2.02.was lower than that in *** main reasons are the decreasing rainfall erosivity and total runoff.

关键词： Modified USLE Gross erosion Sediment delivery ratio

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Sequence analysis of mRNA polyadenylation signals of rice genes

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chinese Science Bulletin 2006年第9期51卷 1069-1077页

作者： LU Ying1, 2. GAO Chenxi1,2.3 & HAN Bin1,3,41. National Center for Gene Research, Shanghai Institutes for Biological sciences, chinese {2. of sciences, Shanghai 2.02.3, china 2. graduate school of the chinese academy of sciences, beijing 10003., china 3. Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological sciences, chinese {2. of sciences, Shanghai 2.0032. china National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200233 China graduate school of the {2. academy of sciences Beijing 100039 China Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

The formation of eukaryotic mRNAs involves the cleavage and polyadenylation of pre- mRNAs. To investigate the sequence requirement of putative polyadenylation signals (PASs), poly(A) sites and downstream elements (DUEs) in 3′-end-pro- cessing in rice, we compared expressed sequences tags (ESTs) with poly(A) extremity to full-length cDNA sequences and constructed a database of 12.69 pre- mRNA sequences in ?40―+40 nt surrounding the poly(A) sites, which were from 9953 genes. The al- ternative poly(A) sites were revealed in approxi- mately 2.% of mRNAs. Nearly 80% of pre-mRNAs showed stringent requirement of the YA (CA or UA) at poly (A) sites for polyadenylation. About 7.9% had the AAUAAA signals on ?40―?1 nt upstream of the poly(A) sites. Over 60% of mRNAs probably used the one- or two-base variants of AAUAAA hexamers as their PASs in 3′ fragments. The single-base variants of AAUGAA revealed the high frequency in 11.5% of 3′ fragments. The DUEs were detected in 90% of pre- mRNAs, especially more than half of the pre-mRNAs with multi-base variants of AAUAAA had the DUEs surrounding the poly(A) site. The location of DUE is also important for defining the cleavage site. Al- though most of the rice pre-mRNAs did not contain AAUAAA signal, the existence of downstream ele- ments ensured the efficiency of cleavage-polyade-

关键词：多聚腺苷酸序列分析 mRNA 水稻基因工程

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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 sciences and Natural Resources Research, chinese {2. of sciences, beijing 100101, china 2. graduate school of the chinese academy of sciences, beijing 10003., china 3. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716, china 4. The Ministry of Science and Technology, P. C. china, beijing 100862. china 5. Chengdu Institute of Biology, chinese {2. of sciences, Chengdu 610041, china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate school of the {2. academy of sciences Beijing China College of Resources and Environment Southwest Agricultural University Chongqing China The Ministry of Science and Technology P. C. China Beijing China Chengdu Institute of Biology Chinese Academy of Sciences 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 9.43%. 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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ON ASYMPTOTIC NORMALITY OF PARAMETERS IN LINEAR EV MODEL

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chinese Annals of Mathematics,Series B 2002年第4期23卷 495-506页

作者： ZHANG SANGUO CHEN XIRUHua Lee-Keng Institue for applied Mathematics and Information Science, graduate school of {2.academy of sciences, beijing 10003., china. Department of Mathematics, graduate school of {2. academy of sciences, Hua Lee-Keng Institue for applied Mathematics and Information Science Graduate School of Chinese Academy of Sciences Beijing 100039 China Department of Mathematics Graduate School of Chinese Academy of Sciences Beijing 100039 China

This paper studies the parameter estimation of one dimensional linear errors-in-variables(EV) models in the case that replicated observations are available in some experimental *** normality is established under mild conditions, and the parameters entering the asymptotic variance are consistently estimated to render the result useable in construction of large-sample confidence regions.

关键词： Errors-in-Variables model Asymptotic normality Replicated observations

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Antisense expression of a rice cellular apoptosis susceptibility gene (OsCAS} alters the height of transgenic rice

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Progress in Natural Science:Materials International 2007年第1期17卷 39-43页

作者： XU Chunxiao and HE Chaozu ( National Key Laboratory of Plant Genomics, Institute of Microbiology, chinese academy of {2., beijing 100080, china graduate University of chinese academy of {2., beijing 10003., china Shenzhen Laboratory of Superhybrid Rice Research, graduate {12. at Shenzhen, Tsinghua University, Shenzhen 518055, china) National Key Laboratory of Plant Genomics Institute of Microbiology Chinese Academy of Sciences Beijing 100080 China

Cellular apoptosis susceptibility (CAS) gene plays important roles in mitosis, development and export of importin a from the nucleus, but its function in plant is unknown. In this study, a rice CAS ortholog (OsCAS), which encodes a predicted protein of 983 amino acids with 62. similarity to human CAS, was identified. DNA gel blot analysis revealed a single copy of OsCAS in the rice genome. A 973 bp fragment at the 3' end of OsCAS cDNA was cloned from rice cDNA library and transferred into rice in the antisense direction under the control of CaMV 35S promoter via Agrobacterium-mediated transformation method, 105 transgenic lines were obtained. Expression of OsCAS was suppressed in the antisense transgenic lines as revealed by semi-quantitative RT-PCR. The antisense transgenic lines showed dwarf phenotypes. The results indicated that OsCAS was involved in culm development of rice.

关键词： antisense dwarf ortholog OsCAS rice.

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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, {2. Normal University, {2. 100875, china 2. State Key Laboratory of Remote Sensing sciences, Institute of Remote Sensing Applications, chinese academy of sciences, {2. 101001, china 3. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, {2. 101001, china 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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SUSPENDED SEDIMENT TRANSPORT IN THE OFFSHORE NEAR YANGTZE ESTUARY

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Journal of Hydrodynamics 2008年第3期20卷 373-381页

作者： CHEN Bin WANG Kai Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate University of the chinese {2. of sciences Beijing 100039 China

Based on the Estuarine, Coastal and Ocean Modeling System with Sediments （ECOMSED） model, a 3-D hydrodynamic-transport numerical model was established for the offshore area near the Yangtze Estuary in the East china Sea .The hydrodynamic module was driven by tide and wind. Sediment module included sediment resuspension, transport and deposition of cohesive and non-cohesive sediment. The settling of cohesive sediment in the water column was modeled as a fimction of aggregation （flocculation） and deposition. The numerical results were compared with observation data for August, 2.06. It shows that the sediment concentration reduces gradually from the seashore to the offshore area. Numerical results of concentration time series in the observation stations show two peaks and two valleys, according with the observation data. It is mainly affected by tidal current. The suspended sediment concentration is related to the tidal current during a tidal cycle, and the maximum concentration appears 1 h-4 h after the current maximum velocity has reached.

关键词： Yangtze Estuary sediment concentration sediment transport

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Chronology of Holocene lacustrine sediments in Co Ngoin, central Tibetan Plateau

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Science china Earth sciences 2006年第9期49卷 991-1001页

作者： WU Yanhong1, WANG Sumin1& HOU Xinhua1,3 1. Key Laboratory of Lake Sedimentation and Environment, Nanjing Institute of Geography and Limnology, chinese academy of {2., Nanjing 2.0008, china 2. Institute of Tibetan Plateau Research, chinese academy of {2., beijing 10085, china 3. graduate University of chinese academy of {2., beijing 10003., china Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China graduate University of chinese {2. of sciences Beijing China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14C, 2.0Pb and 137Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 14C age is always older than the actual age which is recognized as “reservoir effect”. Cs is a kind of active metal element, and easy to migrate vertically in the sediment that leads to the error of the time marker. 2.0Pb dating should make sure to select CIC model or CRS model. On the Tibetan Plateau, most of the lakes are alkaline closed lake where Cs is more moveable in the sediment and the reservoir effect caused by “dead carbon” on 14C dating is stronger. Based on the analysis on results of 14C, 2.0Pb and 137Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14C calendar ages, and establish the time sequence for cores CE-1 and CE-2.with result of 2.0Pb CRS model for the upper 35 cm and re-calculated 14C calendar age for sediments bellow 35 cm. Since 1400 cal. a BP, sedimentation inter-rupted for more than 1000 years. According to this time sequence, variations of environmental proxies confidently reflect the major climatic events in Holocene.

关键词： 14C, 2.0Pb and 137Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

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An improved imaging algorithm for fixed-receiver bistatic SAR

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Science china(Information sciences) 2010年第7期53卷 1461-1469页

作者： GENG XuPu1,2.3, HU YingHui1,2. YAN HongHui2.& WANG YanFei2.1graduate school of the {2. academy of sciences, beijing 10003., china 2.nstitute of Electronics, {2. academy of sciences, beijing 100190, china 3beijing Institute of Environment Features, beijing 100854, china graduate school of the {2. academy of sciences Institute of Electronics Chinese Academy of Sciences beijing Institute of Environment Features

Based on the signal model of fixed-receiver bistatic SAR, this paper analyzes the characteristics of azimuth-variant, which includes variation of range migration curve and variation of Doppler rate caused by different azimuth position of targets. Then, an extended nonlinear chirp scaling (NLCS) algorithm is proposed, with its flowchart and phase compensation functions being provided. Simulation results show that the algorithm is available for the characteristics of azimuth-variant of fixed-receiver bistatic SAR, and good focused radar images could be acquired.

关键词： synthetic aperture radar (SAR) bistatic SAR fixed-receiver characteristics of azimuth-variant range cell migration correction (RCMC)

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A Facile Synthetic Method for (3Z,6Z,9S,10R)-9,10-Epoxy-3,6-heneicosadiene,Sex Pheromone Component of Hyphantria Cunea (Drug)

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chinese Chemical Letters 2005年第4期16卷 468-470页

作者： Chao CHE, Zhong Ning ZHANG StateKey Laboratory IntegratedManagementofInsectsandRodents,Institute of Zoology, chinese academy of {2., beijing 100080 graduate school of the chinese academy of {2., beijing 10003. StateKey Laboratory ofIntegratedManagementofInsectsandRodents Institute of ZoologyChinese Academy of Sciences graduate school of the {2. academy of sciences

Total synthesis of (3Z, 6Z, 9S, 10R)-9, 10-epoxy-3, 6-heneicosadiene, sex pheromone component of Hyphantria cunea (Drug), was achieved using Sharpless AE kinetic resolution and alkylative epoxide rearrangement as ke... 详细信息

关键词： Sex pheromone Hyphantria cunea (Drug) Sharpless kinetic resolution asymmeric synthesis.

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