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Polynomial analysis of canopy spectra and biochemical component content inversion

science china Earth sciences 2005年第10期48卷 1780-1791页

作者： YAN Chunyan1, LIU Qiang1, NIU Zheng1, WANG Jihua2. HUANG Wenjiang2.& LIU Liangyun 2.1. 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. National Engineering research Center for Information Technology in Agriculture, beijing 100089, china 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 china National Engineering research Center for Information Technology in Agriculture beijing{2.

A polynomial expression model was developed in this paper to describe directional canopy spectra, and the decomposition of the polynomial expression was used as a tool for re-trieving biochemical component content from canopy multi-angle spectra. First, the basic formula of the polynomial expression was introduced and the physical meaning of its terms and coeffi-cients was discussed. Based on this analysis, a complete polynomial expression model and its decomposition method were given. By decomposing the canopy spectra simulated with SAILH model, it shows that the polynomial expression can not only fit well the canopy spectra, but also show the contribution of every order scattering to the whole reflectance. Taking the first scattering coefficients a10 and a01 for example, the test results show that the polynomial coefficients reflect very well the hot spot phenomenon and the effects of viewing angles, LAI and leaf inclination angle on canopy spectra. By coupling the polynomial expression with leaf model PROSPECT, a canopy biochemical component content inversion model was given. In the simulated test, the canopy multi-angle spectra were simulated by two different models, SAILH and 4-SCALE re-spectively, then the biochemical component content was retrieved by inverting the coupled polynomial expression + PROSPECT model. Results of the simulated test are promising, and when applying the algorithm to measured corn canopy multi-angle spectra, we also get relatively accurate chlorophyll content. It shows that the polynomial analysis provides a new method to get biochemical component content independent of any specific canopy model.

关键词： polynomial expression, canopy spectra, decomposition, biochemical component content, inversion.

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Seismic wave propagating in Kelvin-Voigt homogeneous visco-elastic media

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science china Earth sciences 2006年第2期49卷 147-153页

作者： YUAN Chunfang1, PENG Suping1, ZHANG Zhongjie2.& LIU Zhenkuan3 1. china University of Mining & Technology, beijing 100083, china 2. institute of Geophysics, Chinese Academy of sciences, beijing 100101, china 3. Exploration and Development research institute of Daqing Oilfield, Daqing 163712. china 1. china University of Mining & Technology Beijing 100083 China 2. institute of Geophysics Chinese Academy of Sciences Beijing 100101 China 3. Exploration and Development research institute of Daqing Oilfield Daqing 163712 China

This paper studies, under a small disturbance, the responses of seismic transient wave in the visco-elastic media and the analytic solution of the corresponding third-order partial differential equation. A plane wave solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differ-ential equation with a pulse source is obtained. By the principle of pulse stacking of particle vibration, the result is extended to the solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differential equation with any source. The velocities of seismic wave propagating and the attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are discussed. The velocities of seismic wave propagating and the coefficient of attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are derived, expressed as functions of density of the media, elastic modulus and visco-elastic coefficient. These results can be applied in inversing lithology parameters in geophysical prospecting.

关键词： Kelvin-Voigt visco-elastic velocity attenuation seismic wave.

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Process and mechanism of arable land change in Hebei Province during the past 50 years

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Journal of geographical sciences 2001年第4期11卷 47-52页

作者： XU Yue-qing (institute of geographical {2.s and natural resources research, CAS, beijing 100101, china College of Resource and Environment {2., Hebei Normal University, Shijiazhuang 050016, china ) CAS Institute of Geographical Sciences and Natural Resources Research Beijing China (GRID:grid.9227.e) (ISNI:***) Hebei Normal University College of Resource and Environment Science Shijiazhuang China (GRID:grid.256884.5) (ISNI:***)

Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in china. The contradiction of land shortage sharpened by high-speed economic development with population growth has become a serious problem, which has restricted regional sustainable *** paper revealed the basic process, regional differences of change and the gravity center of arable land area according to the long-series statistical data of arable land during the past 50 years. On the basis of the above mentioned, the major driving forces that influence the changes of the arable land are discussed. The research results indicate that there is a trend of obvious fluctuating decrease in arable land area during the last 50 years. The changes of arable land area undergo the process from increase to sharp decrease to gently decrease. The regional disparity of change in arable land area is very notable and the gravity center of arable land area moves to the northeast 49.2. km. Regarding the decrease in arable land, the direct driving forces include adjustments of agricultural structure and reclamation, and indirect driving forces include advance in technology, economic interest and population growth etc.

关键词： decrease in arable land area changing process mechanism Hebei Province

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IMPACTS OF FLOOD EVENTS IN COARSE SEDIMENT-PRODUCING AREAS ON CHANNEL SILTATION AND FLUVIAL PROCESS OF THE LOWER YELLOW RIVER

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International Journal of Sediment research 2007年第2期22卷 142-149页

作者： Ou-yang ZHANG1, Xiufu FENG2.and Jiong-xin XU31 Bureau of Hydrology, Changjiang Water resources Commission, Hubei, Wuhan 430010, china2.Chengdu University of technology, Sichuan, Chengdu 610059, china3institute of geographic sciences and natural resources research, CAS, beijing 100101, china Changjiang Water resources Commiss Bureau Hydrol Wuhan 4310010 Peoples R China Chengdu Univ Technol Chengdu 610059 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China

The method of multiple regression is used to analyze the influences of flood events from the coarse sediment producing areas on the channel siltation and fluvial process of the lower Yellow River based on the flood events from 1950 to 1985. The results showed that the flood events from the coarse sediment producing areas carry larger amounts of sediment load and coarser particle sizes than from other source areas, which increases deposition in the lower river channel. And there exist good correlations between channel siltation of the lower reaches of the Yellow River and the coming water and sediment of flood events from the coarse sediment producing areas. Through these correlations, the amounts of sediment deposition in the lower river channel could be roughly estimated based on the runoff and sediment load of flood events from the coarse sediment producing areas. The sediment deposition caused the fluvial process. There exists a complex response of channel form change to the coming water and sediment load of flood events from the coarse sediment producing areas. When the sediment concentration is smaller than 2.0kg/m3, the ratio between wide-depth ratio after flood and wide-depth ratio before flood((B/h)a / (B/h)b) will increase with the increase of the maximum sediment concentration; when the sediment concentration is near 2.0kg/m3, (B/h)a / (B/h)b reaches the maximum value; and when the sediment concentration reaches the limits of hyperconcentrated flow, (B/h)a / (B/h)b will decrease with the increase of the maximum sediment concentration. Generally, flood events from the coarse sediment producing areas made channel form of the lower Yellow River deeper and narrower, but a large amount of sediment deposition simultaneously occurs. So, the impacts of flood events from the coarse sediment producing areas on the channel of the lower Yellow River are lessened.

关键词： Channel siltation Fluvial process Coarse sediment-producing areas Flood events Yellow River basin

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The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, china

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science china Earth sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3 & WANG Lei2.1. institute of Tibetan Plateau research, Chinese Academy of {2.s, beijing 100085, china 2. Faculty of Earth {2.s and Mineral resources, china University of Geo{2.s, beijing 100083, china 3. Tianjin institute of Geology and Mineral resources, Tianjin 300170, china 1. institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China 2. Faculty of Earth sciences and Mineral resources China University of Geosciences Beijing 100083 China 3. Tianjin institute of Geology and Mineral resources Tianjin 300170 China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

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Saline-alkali land in the Yellow River Delta: amelioration zonation based on GIS

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Journal of geographical sciences 2001年第3期11卷 313-320页

作者： GUAN Yuan-xiu, LIU Gao-huan, WANG Jin-feng (State Key Laboratory of resources and Environment Information System, institute of {2. sciences and natural resources research, CAS, beijing 100101, china) State Key Laboratory of resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research CAS

Soil salinization is one of the major land degradation types and has greatly influenced sustainable agricultural development. Zonation of saline-alkali land is the precondition for effective amelioration. The present situation of saline-alkali land is monitored by remote sensing image processing. Causes for land salinization are analyzed, especially the two key factors, ground water depth and its mineralization degree, are analyzed by using long-term observation data. Previously, zonation of saline-alkali soil was made descriptively and artificially. Based on the present situation of saline-alkali land, ground water depth and ground water mineralization degree, the zonation of saline-alkali land for amelioration in the Yellow River Delta was completed quantitatively. Four different types of saline-alkali land amelioration zones are delineated, namely, easy ameliorated zone, relatively difficult ameliorated zone, difficult ameliorated zone and unfavorable ameliorated zone. Countermeasures for ameliorating saline-alkali soils are put forward according to ecological conditions of different saline-alkali land zones.

关键词： GIS the Yellow River Delta saline-alkali land zonation

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GIAHS Project and Its Implementation in china

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Journal of resources and Ecology 2010年第1期1卷 94-96页

作者： MIN Qingwen~1,SUN Yehong~(1,2. and SHI Yuanyuan~1 1.institute of geographic {2.s and natural resources research,CAS,beijing 100101,china 2.Graduate University of Chinese Academy of {2.s,beijing 100049,china 1. institute of geographic {2.s and natural resources research CAS Beijing 100101 China 2. Graduate University of Chinese Academy of sciences Beijing 100049 China

GIAHS Project and Concept In 2.02.Food and Agriculture Organization of the United Nations(hereafter FAO)started an initiative for the conservation and adaptive management of Globally Important Agricultural Heritage Sy... 详细信息

关键词： GIAHS Project and Its Implementation in china Project

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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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science china Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3 & YE Xianren2.1. resources and Environmental School, Lanzhou University, Lanzhou 730000, china 2. Key Laboratory of Gas Geochemistry, {2. of Geology and Geophysics, Chinese Academy of sciences, Lanzhou 730000, china 3. College of resources science & Technology, beijing Normal University, beijing 100875, china 1. resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of resources science & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3He/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3He from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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Growth characteristics and response to climate change of Larix Miller tree-ring in china

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science china Earth sciences 2010年第6期53卷 871-879页

作者： SUN Yu1,4, WANG LiLi1,2.3, CHEN Jin5, DUAN JianPing1,4, SHAO XueMei1,2.& CHEN KeLong6 1 institute of geographic {2.s and natural resources research, Chinese Academy of {2.s, beijing 100101, china 2.institute of Tibetan Plateau research, Chinese Academy of {2.s, {12. 100085, china 3 institute of Desert and Meteorology, china Meteorological Administration, Urumqi 830002. china 4 Graduate University of Chinese Academy of {2.s, {12. 100049, china 5 institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of {2.s, {12. 100044, china 6 School of Life and Geography {2.s, Qinghai Normal University, Xining 810008, china 1. institute of geographic {2.s and natural resources research Chinese Academy of Sciences Beijing 100101 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China3. Institute of Desert and Meteorology China Meteorological Administration Urumqi 830002 China5. Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China6. School of Life and Geography Sciences Qinghai Normal University Xining 810008 China

As one of the earliest species used in dendrochronological studies, Larix responds sensitively to climate change. In this study, nine larch species and one variety from eleven sites were collected to study the growth characteristics of tree-ring width using dendrochronological methods. Ten residual tree-ring chronologies were developed to analyze their relationships with regional standardized anomaly series by Pearson’s correlation analysis. The results suggest that most of the chronologies had significantly positive correlations with the mean temperature and mean maximum temperature in May. The spring temperature evidently limited the radial growth of the larch species without precipitation control. The largest mean tree-ring width was found in Himalayan Larch in Jilong, whereas Master Larch in Si’er reflected the smallest mean value. Both species presented little climate information in this study. Chinese, Potanin, and Tibetan larches are significantly correlated with climate change, implying a huge potential for climate history reconstruction. The elevation of the sampling sites appears to be an important condition for tree-ring growth of larches responding to climate factors.

关键词： Larix Miller tree-ring climate change mean temperature in May

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Functionally assessing the sustainability of regional ecosystem services:a case study of Hohhot City

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research in Cold and Arid Regions 2010年第2期2卷 175-184页

作者： Ling Feng institute of geographic {2.s and natural resources research,Chinese Academy of {2.s,beijing 100101,china institute of geographic {2.s and natural resources research Chinese Academy of SciencesBeijing 100101China

"The value of the world’s ecosystem services and natural capital" by *** et *** 1997 is generally regarded as a monument to the research of valuing ecosystem ***,the classification of ecosystem services,the method of various services summation,and the purpose for static global value had many *** on a summary of these criticisms and suggestions,further study direction—on the sustainability of ecosystem services—is *** two basis indicators in ecology—productivity and biodiversity,respectively characterize the ability of producing and self-organizing—not only represent the internal function of ecosystem,but also can be proportioned to its external function of supporting and providing for human ***,the two indicators combined could physically assess the sustainability of ecosystem services based on the traditional procedure of Costanza’*** case study of Hohhot City in 1995-2.05 shows that the new model reflects the changes of ecosystem services at spatial and temporal scale,and the functionally adjusted assessment shows the sustainability of Hohhot City became gradually stronger during the study *** due to the enormous value per unit of water ecosystem,the minimal loss of water area leads to the final result being opposite to the processing analysis,which gives a clue to the further experimental testing research.

关键词： ecosystem services sustainability bio-productivity biodiversity

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