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ANALYSIS OF DRIVING FORCES ON THE CHANGE OF HISTORICAL FARMLAND USE IN SHANDONG PROVINCE DURING THE QING DYNASTY (1.44-1.1.)

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chinese {1. Science 2003年第3期13卷 207-215页

作者： zhang Xue-in, GE Quan-heng, zheng Jing-un({2. of Geographic sciences and natural resources research, chinese Academy of sciences, beijing 100101, P. R. china) institute of Geographic {1. and {2. resources research Chinese Academy of Sciences Beijing P. R. China

How land-cover has been changed by human use over the last 300 years is oneof the five overarching questions guiding the Land-use/Cover Change (LUCC) Science/research *** has variety of historical documents providing unique data superiority. So the characteristicsof farmland area in Shandong Province during the Qing Dynasty (1.44-1.1.) are summarized firstly: 1.the rising trend of farmland area was striking; {1. farmland area had remarkable fluctuation; 3)farmland area per capita decreased dramatically; 4) wasteland reclamation index increased ***, the driving forces of farmland area change are analyzed. It is concluded that natural andhuman factors are jointly influential. Among the driving forces, human dimensions are the mainfactors of farmland area change, which direct the general tendency of the changes mentioned *** the natural factors influence the stability of farmland area as well. Variation of the naturalfactors would act as the major contributory factor to farmland area change during years or periodsof abrupt climatic changes, or during the intensive occurring periods of natural hazards. Besides,the passive aspects of human factors, such as war chaos also influenced the fluctuation of thefarmland area. This research indicates that it is feasible to study the land-use/cover change bychinese historical literatures, which has huge potential to provide a comprehensive picture of thegrowing dominance of human land-use and land-cover patterns that can be used in many global changeresearch projects.

关键词： farmland driving forces shandong province qing dynasty

Quantitative estimation of the shrub canopy LAI from atmosphere-corrected HJ-1.CCD data in Mu Us Sandland

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Science china Earth {1. 2010年第S1期53卷 26-33页

作者： CHEN wei1,2,CAO ChunXiang1,HE QiSheng1,2,GUO huaDong3,zhang Hao1,2,LI RenQiang4,zheng Sheng1,2,XU Min1,2,GAO MengXu1,2,ZHAO Jian1,2,LI Sha1,NI XiLiang1,2,JIA HuiCong1,JI wei1,TIAN Rong1,2,LIU Cheng1,2,ZHAO YuXing5 & LI JingLu6 1 State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the institute of Remote Sensing Applications of chinese Academy of sciences and beijing Normal University,beijing 100101,china 2 Graduate University of chinese Academy of sciences,beijing 100049,china 3 Center for Earth Observation and Digital Earth,chinese Academy of sciences,beijing 100190,china 4 china Key Laboratory of Ecological Network Observation and Modeling,institute of geographical sciences and natural resources research,chinese Academy of sciences,beijing 100101,china 5 Ordos Forestry Sand Control Science institute,Dongsheng 017000,china 6 Inner Mongolia Biomass Thermoelectricity Limited Company,Wushen 017300,china 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China 2. Graduate University of {1. Academy of sciences Beijing 100049 China 3. Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China 4. china Key Laboratory of Ecological Network Observation and Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 5. Ordos Forestry Sand Control Science institute Dongsheng 017000 China 6. Inner Mongolia Biomass Thermoelectricity Limited Company Wushen 017300 China

The leaf area index(LAI) is an important ecological parameter that characterizes the interface between vegetation canopy and the *** addition,it is used by most process-oriented ecosystem *** paper investigates the potential of HJ-1.CCD data combined with linear spectral unmixing and an inverted geometric-optical model for the retrieval of the shrub LAI in Wushen Banner of Inner Mongolia in the Mu Us ***(Moderate Resolution Atmospheric Radiance and Transmittance Model) was used for atmospheric *** was extracted using the threshold of the normalized difference vegetation index,with which water bodies and farmland were separated,in combination with a vegetation map of the People's Republic of china(1.1.00000).Using the geometric-optical model,we derive the per-pixel reflectance as a simple linear combination of two components,namely sunlit background and *** fraction of sunlit background is related to the shrub *** the support of HJ-1.CCD data,we employ linear spectral unmixing to obtain the fraction of sunlit background in an atmospherically corrected HJ *** addition,we use the measured shrub canopy structural parameters for shrub communities to invert the geometric-optical model and retrieve the pixel-based shrub *** total,1. sample plots collected in Wushen Banner of Inner Mongolia are used for *** results of the shrub LAI show good agreement with R{1.of 0.81. and a root-mean-squared error of 0.1.3.

关键词： shrub leaf area index inversion HJ-1 data geometric-optical model MODTRAN Mu Us Sandland

Land use and landscape pattern change: a linkage to the construction of the Qinghai-Xizang Highway

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Journal of geographical {1. 2002年第3期12卷 253-265页

作者： YAN Jianzhong, zhang Yili, LIU Linshan, LIU Yan{1.2. {2. Du (1. Inst. of Geographic sciences and natural resources research, CAS, beijing 100101, china 2. The Ministry of Science and Technology, beijing 100101, china 3. College of resources and Enviro Inst. of Geographic sciences and {1. {2. research CAS Beijing China College of resources andEnvironment Southwest Agricultural University Chongqing China The Ministry of Science and Technology Beijing China

Based on digital land use data from 1.95 to 2.00 and road data, the land use and landscape changes of Golmud, Qumaleb and Zhidoi are studied on a macro-scale. Land use and landscape changes in highway buffer zones and city expansion are special subjects. A new formula is used to define the exact degree of dynamic land use. To adequately define land use and landscape pattern changes, the buffer zones, illustrating the changes at different distances from the road, are recognized with ArcGIS 8.1.software. Prominent changes took place in land use and landscape patterns from 1.95 to 2.00, and the area of built-up land increased by 32..8%. The comprehensive degree of dynamic land use is 2.2., and the degree of dynamic land use of built-up land is the highest, followed by cultivated land. Woodland has the lowest value. The used degree index of land resources declined by 38.8 from 1.95 to 2.00. Landscape changed dramatically which influenced ecological processes immensely. Different from the corridor effect of other traffic routes, the corridor effect of this section of road is not obvious and its “point” radiation effect can be easily seen. The expanding range of Golmud City is confined to a 3 km buffer, while for Wudaoliang, it is 1.km. No land use change happened in the Nanshankou buffer.

关键词： land use change comprehensive index of the degree of land use diagnostic index of landscape degree of dynamic land use Qinghai-Xizang Highway

Scale effects of leaf area index inversion based on environmental and disaster monitoring satellite data

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Science china Earth {1. 2010年第S1期53卷 92-98页

作者： zhang Hao1,LI XiaoWen1,2.CAO ChunXiang1,YANG hua2.GAO MengXu1,3,{2. Sheng1,3,XU Min1,3,XIE DongHui2.JIA HuiCong1,JI wei1,ZHAO Jian1,3,CHEN wei1,3 & NI XiLiang1,3 1 State Key Laboratory of Remote Sensing Science,Jointly Sponsored by institute of Remote Sensing Applications,chinese Academy of sciences and beijing Normal University,beijing 100101,china 2.State Key Laboratory of Remote Sensing Science,Jointly Sponsored by beijing Normal University and institute of Remote Sensing Applications of chinese Academy of sciences,beijing 100875,china 3 Graduate University of chinese Academy of sciences,beijing 100049,china 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China2. State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing 100875 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The spatial distribution of sub-pixel components has an impact on retrieval accuracy,and should be accounted for when inverting a three-dimensional adiative transfer model to retrieve leaf area index(LAI).To investigate this effect,we constructed three realistic scenarios with the same LAI values and other properties,except that the simulated plants had different *** implemented the radiosity method to subsequently produce synthetic bidirectional reflectance factor(BRF) datasets based upon these simulated *** inversion was conducted using these data,which showed that spatial distribution affects retrieval *** inversion was also conducted for LAI based on charge-coupled device(CCD) data from the Environment and Disaster Monitor Satellite(HJ-1.,which depicted both forest and drought-resistant crop land *** showed that heterogeneity in coarse-resolution remote sensing data is the main error source in LAI *** spatial distribution of global fractal dimension index,which can be used to describe the area of sub-pixel components and their spatial distribution modes,shows good consistency with the coarse resolution LAI inversion error.

关键词： HJ-1 leaf area index scale effect spatial distribution

Health risks and sources of trace elements and black carbon in PM_(2.5)from 2.1. to 2.2. in beijing

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Journal of Environmental sciences 2024年第8期142卷 69-82页

作者： Chenjie hua {1. Ma Feixue {2. Yusheng zhang Jiali Xie Li Ma Boying Song Chao Yan Hongyan Li Zhen Liu Qian Liu Markku Kulmala Yongchun Liu Aerosol and Haze Laboratory Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China institute for Atmospheric and Earth System {1. Faculty of ScienceUniversity of HelsinkiHelsinki 00014Finland School of Environment and Safety Taiyuan University of Science and TechnologyTaiyuan 030024China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

A comprehensive health risk assessment of PM_(2.5)is meaningful to understand the current status and directions regarding further improving air quality from the perspective of human *** this study,we evaluated the health risks of PM_(2.5)as well as highly toxic inorganic components,including heavy metals(HMs)and black carbon(BC)based on longterm observations in beijing from 2.1. to *** results showed that the relative risks of chronic obstructive pulmonary disease,lung cancer,acute lower respiratory tract infection,ischemic heart disease,and stroke decreased by 4.07%-9.30%in 2.2. and 2.1.0}-6.70%in2.2. compared with ***,they were still at high levels ranging from 1.2. to 1.77,in particular,stroke showed the highest value in *** had the highest hazard quotient(HQ,from 2.1. to 2.56)for adults from 2.1. to 2.2.,while Ni,Cr,Pb,As,and BC showed high carcinogenic risks(CR>1.0×1.^(-6))for *** HQ values of Mn and As and the CR values of Pb and As showed constant or slight upwards trends during our observations,which is in contrast to the downward trends of other HMs and PM_(2.5).Mn,Cr,and BC are crucial toxicants in PM_(2.5).A significant shrink of southern region sourcesof HMs and BCshrank suggests the increased importance of local ***,dust,and biomass burning are the major contributors to the non-carcinogenic risks,while traffic emissions and industry are the dominant contributors to the carcinogenic risks in beijing.

关键词： PM_(2.5) Heavy metals Black carbon Health risk Source apportionment

Observation of spectral lines in the exceptional GRB 2.1.09A

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Science china(Physics,Mechanics & Astronomy) 2024年第8期67卷 187-206页

作者： Yan-Qiu zhang Shao-Lin Xiong Ji-Rong Mao S{1.ng-Nan zhang Wang-Chen Xue Chao zheng Jia-Cong Liu Zhen zhang Xi-Lu Wang Ming-Yu Ge Shu-Xu Yi Li-Ming Song zheng-{1. An Ce Cai Xin-Qiao Li Wen-Xi Peng Wen-Jun Tan Chen-wei Wang Xiang-Yang Wen Yue Wang Shuo Xiao Fan zhang Peng zhang Shi-Jie zheng Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of chinese Academy of {1. Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China College of Physics and Hebei Key Laboratory of Photophysics research and Application Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China

As the brightest gamma-ray burst ever observed,GRB 2.1.09A provided a precious opportunity to explore spectral line *** this article,we performed a comprehensive spectroscopy analysis of GRB 2.1.09A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption *** the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems,and identified prominent emission lines in multiple time *** central energy of the Gaussian emission line evolves from about 37 to 6 MeV,with a nearly constant ratio(about 1.%)between the line width and central ***,we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of–1.and–2.*** suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 51. ke V *** find that a standard high latitude emission scenario cannot fully interpret the observation,thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the *** this scenario,we can use the emission line to directly,for the first time,measure the bulk Lorentz factor of the jet(Γ)and reveal its time evolution(i.e.,Γ~t^(-1.)during the prompt ***,we find that the flux of the annihilation line in the co-moving frame keeps *** discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.

关键词： GRB GRB 2.1.09A emission line

Detector performance of the Gamma-ray Transient Monitor onboard DRO-A satellite

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Science china(Physics,Mechanics & Astronomy) 2024年第11期67卷 75-90页

作者： Pei-Yi Feng zheng-{1. An Da-Li {2. Chen-wei Wang Chao zheng Sheng Yang Shao-Lin Xiong Jia-Cong Liu Xin-Qiao Li Ke Gong Xiao-Jing Liu Min Gao Xiang-Yang Wen Ya-Qing Liu Xiao-Yun Zhao Fan {2. Xi-Lei Sun Hong Lu Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of chinese Academy of {1. Beijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The Gamma-ray Transient Monitor(GTM) is an all-sky monitor onboard the Distant Retrograde Orbit-A(DRO-A) satellite with the scientific objective of detecting gamma-ray transients ranging from 2. ke V to 1.MeV. The GTM was equipped with five Gamma-ray Transient Probe(GTP) detector modules utilizing a NaI(Tl) scintillator coupled with a SiPM array. To reduce the SiPM noise, GTP uses a dedicated dual-channel coincident readout design. In this work, we first studied the impact of different coincidence times on the detection efficiency and ultimately selected a 0.5 μs time coincidence window for offline data processing. To test the performance of the GTPs and validate the Monte-Carlo-simulated energy response, we conducted comprehensive ground calibration tests using the Hard X-ray Calibration Facility(HXCF) and radioactive sources, including the energy response, detection efficiency, spatial response, bias-voltage response, and temperature dependence. We extensively present the ground calibration results and validate the design and mass model of the GTP detector, thus providing the foundation for in-flight observations and scientific data analysis.

关键词： NaI(Tl)detector energy response ground calibration gamma-ray detector DRO-A satellite

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森林生态系统的水源涵养功能及其计量方法

生态学杂志 2009年第3期28卷 529-534页

作者：张彪李文华谢高地肖玉中国科学院地理科学与资源研究所北京100101 中国科学院研究生院北京100039

为全面认识与正确评价森林生态系统的水源涵养功能,本文探讨了其概念、表现形式及其计量方法,认为:1.森林的水源涵养功能是一个动态、综合的概念,随着人们对森林水文作用认识的不断深入,其内涵不断丰富扩大,因此森林的水源涵养功能概念... 详细信息

为全面认识与正确评价森林生态系统的水源涵养功能,本文探讨了其概念、表现形式及其计量方法,认为:1.森林的水源涵养功能是一个动态、综合的概念,随着人们对森林水文作用认识的不断深入,其内涵不断丰富扩大,因此森林的水源涵养功能概念存在狭义和广义之分;2.森林的水源涵养功能(广义)有多种表现形式,包括拦蓄降水、调节径流、影响降雨和净化水质等,不过其具体表现形式与研究对象、研究目的以及研究尺度有关;3)目前森林拦蓄降水功能的计量方法主要有土壤蓄水能力法、水量平衡法、年径流量法和多因子回归法等8种,不过这些方法都存在一定的局限性,实际应用中需要综合考虑。

关键词：森林生态系统水源涵养功能表现计量方法

Atom-referenced and stabilized soliton microcomb

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Science china(Physics,Mechanics & Astronomy) 2024年第2期67卷 2-8页

作者： Rui Niu Shuai Wan Tian-Peng hua {2.-Qiang Wang zheng-Yu Wang Jin Li Zhu-Bo Wang Ming Li Zhen Shen Yu Robert Sun Shui-Ming Hu Brent ELittle Sai Tak Chu {2. Zhao Guang-Can Guo Chang-Ling Zou Yun-Feng Xiao Wen-Fu zhang Chun-hua Dong State Key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China University of chinese Academy of {1. Beijing 100049China Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Department of Physics and Materials Science City University of Hong KongHong Kong 999077China State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China

For the applications of the frequency comb in microresonators,it is essential to obtain a fully frequency-stabilized microcomb laser *** this study,we present a system for generating a fully atom-referenced stabilized soliton *** pump light around 1.60.48 nm is locked to an ultra-low-expansion(ULE)*** pump light is then frequency-doubled and referenced to the atomic transition *** repetition rate of the soliton microcomb is injection-locked to an atomic-clockstabilized radio frequency(RF)source,leading to mHz stabilization at 1.*** a result,all comb lines have been frequencystabilized based on the atomic reference and the ULE cavity,achieving a very high precision of approximately 1. Hz at 1.s,corresponding to the frequency stability of 9.5×1.^(-1.).Our approach provides a fully stabilized microcomb experiment scheme with no requirement of f-2. technique,which could be easily implemented and generalized to various photonic platforms,thus paving the way towards the ultraprecise optical sources for high precision spectroscopy.

关键词： microcavity frequency comb dissipative Kerr solitons fully stabilized microcomb