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Wetland vegetation biomass estimation and mapping from Landsat ETM data: a case study of Poyang Lake

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Journal of Geographical Sciences 2002年第1期12卷 35-41页

作者： LI Ren-dong1, 2. LIU Ji-yuan2.(1. institute of Geodesy and geophysics, caS, Wuhan 430077, China 2. institute of Geographic Sciences and Natural Resources Research, caS, Beijing 100101 China) institute of Geodesy and geophysics CAS Wuhan China institute of Geographic Sciences and Natural Resources Research CAS Beijing China

Poyang Lake is the largest freshwater lake in China. This paper conducted a digital and rapid investigation of the lake’s wetland vegetation biomass using Landsat ETM data acquired on April 16, 2.00. First, utilizing the false color composite derived from the ETM data as one of the main references, the authors designed a reasonable sampling route for field measurement of the biomass, and carried it out on April 18–2., 2.00. Then after both the sampling data and the ETM data were geometrically corrected to an equal-area projection of Albers, linear relationships among the sampling data and some transformed data derived from the ETM data and the ETM 4 were calculated. The results show that the sampling data is best relative to the band 4 data with a high correlation coefficient of 0.86, followed by the DVI and NDVI data with 0.83 and 0.80 respectively. Therefore, a linear regression model, which was based on the field data and band 4 data, was used to estimate the total biomass of entire Poyang Lake, and then the map of the biomass distribution was compiled.

关键词： Poyang Lake biomass wetland vegetation Landsat ETM data

A new method for spatio-temporal prediction of rainfall-induced landslide

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Science China Earth Sciences 2006年第4期49卷 421-430页

作者： DING Jixin1,2. YANG Zhifa2. SHANG Yanjun2. ZHOU Shenghua1 & YIN Juntao3 1. China Non-ferrous Metals Resource Geological Survey, Beijing 100012. China 2. institute of Geology and geophysics, Chinese Academy of Sciences, Key Laboratory of Engineering Geomechanics, Beijing 10002., China 3. School of Geoscience & Environmental Engineering, Central South {2., Changsha 410083, China 1. China Non-ferrous Metals Resource Geological Survey Beijing 100012 China 2. institute of Geology and geophysics Chinese Academy of Sciences Key Laboratory of Engineering Geomechanics Beijing 100029 China 3. School of Geoscience & Environmental Engineering Central South University Changsha 410083 China

Geological condition and rainfall are two most principal conditions inducing landslides in the Chongqing region. By analyzing the forming conditions of rainfall-induced landslides, a new method for spatio-temporal prediction of rainfall-induced landslide is brought forward on the basis of grading and overlapping geological condition and rainfall factor in this paper. At first, semi-quantitative assessment and grading for the geological condition of a certain area or slope can be carried out with the multi-factor interactive matrix. Then the severity of rainfall in that area is grading according to the maximum daily rainfall and the total rainfall in a rainfall course. Finally, the “landslide probability judgement factor” can be worked out through grading and overlapping “geological condition influenc- ing factor” and “rainfall influencing factor”, by which the landslide can be graded into 4 grades, they are landslide extremely easily happening, landslide easily happening, landslide difficultly happening and landslide hardly ever happening respectively. More accurate spatio-temporal prediction of rain- fall-induced landslides can come true on the ground of detailed geological survey of some dangerous slopes in an area and more precise weather forecast. Finally, the reliability and feasibility of carrying out the spatio-temporal prediction of rainfall-induced landslides with the method of “two factors” grading and overlapping are validated by the example of Jipazi landslide.

关键词： rainfall-induced landslide, geological condition, rainfall, two factors, grading and overlapping, interactive matrix, spatio-temporal prediction.

Method of multi-level recursive and application to nonlinear dynamic deformation forecasting

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中国有色金属学会会刊：英文版 2005年第S1期15卷 172-175页

作者： LIU Guo-lin~(1, 2., ZHANG Lian-peng~2. OU Ji-kun~1 (1. institute of Geodesy and geophysics, Chinese Academy of Science, Wuhan, 430077,China 2. Shandong {2. of Science and Technology, Tai’an 2.1019, China) Chinese Acad Sci Inst Geodesy & Geophys Wuhan 430077 Peoples R China Shandong Univ Sci & Technol Tai An 271019 Peoples R China

The time-dependence bilinear mixed-regression deformation model and time-dependence bilinear dynamic system deformation model are established for deformation observation series. According to the multi- level recursive method, the time-dependence parameters are first traced and predicted, and then the dynamic system states. Due to the method considering time-dependence of deformation and having stronger adaptability to time-dependence system, it can improve forecast’s precision. It is very effective for data processing of nonlinear dynamic deformation monitoring to make multi-step forecasting.

关键词： multi-level recursive dynamic monitoring timedependence parameters

The freeze-thaw metallogenic model of regenerated gold placers under cold low temperature conditions

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Chinese Science Bulletin 1999年第S2期44卷 11-13页

作者： ZHANG Baolin~1, WANG Chunhe~2. WANG Jie~1 and SONG Changchun~2.1. institute of Geology and geophysics, Chinese Academy of Sciences, Beijing 10002., China 2. Changchun institute of Geography, Chinese Academy of Sciences, Changchun 13002., China institute of Geology and geophysics Chinese Academy of Sciences Beijing 100029 China Changchun institute of Geography Chinese Academy of Sciences Changchun 130021 China

LOcaTED in the mined-out areas of primary gold placers, the regenerated gold placers in permafrost zonesare a kind of special low temperature deposit formed under modem cold climate conditions. Although theregeneration phenomenon was first discovered in South America, the scale and periodicity of the regeneration are more evident in permafrost environment of Northern Hemisphere.

关键词： regeneration gold placer freeze-thaw model.

Forcing mechanism of the Pleistocene east Asian monsoon variations in a phase perspective

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Science China Earth Sciences 2005年第10期48卷 1708-1717页

作者： TIAN Jun1,2. WANG Pinxian1, CHENG Xinrong1, WANG Rujian1 & SUN Xiangjun1,3 1. State Key Laboratory of Marine Geology, Tongji university, Shanghai 2.0092. China 2. institute of Geology and {2., Chinese Academy of Sciences, Beijing 10002., China 3. institute of Botany, Chinese Academy of Sciences, Beijing 100093, China State Key Laboratory of Marine Geology Tongji university Shanghai China institute of Geology and geophysics Chinese Academy of Sciences Beijing China institute of Botany Chinese Academy of Sciences Beijing China

The deep sea records from the ODP Sites 1143 and 1144 in the northern and southern South China Sea (SCS), including foraminiferal δ 18O and δ 13C, Opal% and pollen percentage, reveal that the variations of the east Asian monsoon have been closely correlated with the variations of the Earth’s orbital parameters (eccentricity, obliquity and precession) and the global ice volume on orbital scale. All the monsoonal proxies show strong 100 ka, 41 ka and 2. ka cycles. Although G. ruber δ 13C of Site 1143 is coherent with the ETP (ETP= normalized (eccentricity + obliquity-precession) at eccentricity, obliquity and precession bands, most of the coherent relationship focuses on the precession band, and the other monsoonal proxies are coherent with the ETP only at the precession band, which indicate that precession dominates the Pleistocene tropical climate changes. The phase relationship of the monsoonal proxies with the foraminiferal δ 18O implies that the global ice volume changes have played a significant role in modulating the east Asian monsoon climate, at least dominating the winter monsoon. This forcing mechanism of the east Asian monsoon is apparently different from that of the Indian ocean mon-soon. The variations of the east Asian monsoon at the precession band, at least that of the winter monsoon, have been controlled not only by the sensible heating but also by the latent heating of the surface water in the South China Sea.

关键词： South China Sea, ODP, east Asian monsoon, orbital forcing, global ice volume.

Oxygen isotope compositions of eclogites in Rongcheng,Eastern China

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Chinese Science Bulletin 2003年第4期48卷 372-378页

作者： CHU Xuelei1,2. GUO Jinghui1,2. FAN Hongrui1,2.& JIN Chengwei1 1. institute of Geology and geophysics, Chinese Academy of Sciences, Beijing 10002., China 2. Key Laboratory for Mineral Resources Research, Chinese Academy of Sciences, Beijing 100101, China Correspondence should be addressed to Chu Xuelei institute of Geology and geophysics Chinese Academy of Sciences Beijing 100029 China Key Laboratory for Mineral Resources Research Chinese Academy of Sciences Beijing 100101 China

Collected from the Rongcheng region, Shan-dong Province, the three types of eclogites suffering the UHP (i.e. ultra-high pressure) metamorphism have obviously dif-ferent oxygen isotope compositions. The eclogites occurring in regional orthogneisses and ultramafic rocks have the oxy-gen isotope compositions of normal eclogites in the world,but the eclogites existing in marbles are extremely enrichedin 18O. By applying oxygen isotope geothermometry, for theall types of eclogites, the temperature estimates of quartz-garnet pair, in principle, indicate the formation temperatures of eclogites, so that the peak-metamorphic temperatures are estimated to be averagely little higher than 800℃, which are consistent with the estimates by using other geothermome-ters according to cation partitioning between coexistingphases. The d 18O values of eclogitic inclusions hosted inmarbles from Yangguantun, Rongcheng region, are farhigher than the values of eclogites (including eclogitic inclu-sions in marbles) from the Dabieshan and other places of the Sulu. The oxygen isotope compositions of various mineralsindicate that the formation temperatures of eclogites fromthe Rongcheng region, in general, are higher than that from the Dabieshan and the southwestern part of the Sulu, but the dispersive temperatures estimated by different mineral pairs probably reflect that the UHP eclogites from the Rongcheng region generally suffered overprinted metamorphisms dur-ing the exhumation.

关键词：苏鲁超高压变质带 UHP 山东荣成榴辉岩氧同位素成分

Variation properties of ionospheric eclipse factor and ionospheric influence factor

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Progress in Natural Science:Materials International 2005年第6期15卷 573-576页

作者： ZHAO Chunmei 1,2.*, YUAN Yunbin1, OU Jikun1 and CHEN Jinping3(1. institute of Geodesy and geophysics, Chinese Academy of Sciences, Wuhan 430077, China 2. Graduate School of Chinese Academy of Sciences, Beijing 100039, China 3. Department of Precision Instrument and Mechanology, Tsinghua {2., Beijing 100084, China) institute of Geodesy and geophysics Chinese Academy of Sciences Wuhan 430077 China Graduate School of Chinese Academy of Sciences Beijing 100039 China Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The concepts and calculation methods of ionospheric eclipse factor (IEF) and ionospheric influence factor (IFF) are further illustrated. The temporal and spacial variation properties of IEF and IFF are studied, which shows that the properties are influenced by the geographic position and season. The possibility of improving the precision of using GPS data to determine ionospheric delay based on the above variation properties is also analysed.

关键词： GPS ionospheric eclipse factor ionospheric influence factor

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science China Earth Sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2.& LU Yang1,3 1. institute of Geodesy and geophysics, Chinese Academy of Sciences, Wuhan 430077, China 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 3. Unite Center for Astro-geodymics Research, Chinese Academy of Sciences, Shanghai 2.0030, China 1. institute of Geodesy and geophysics Chinese Academy of Sciences 430077 Wuhan China 2. Graduate School of the Chinese Academy of Sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 2.0 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

Tectonic setting of the Helong Block:Implications for the northern boundary of the eastern North China Craton

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Science China Earth Sciences 2005年第10期48卷 1599-1612页

作者： ZHANG Yanbin1, WU Fuyuan1, ZHAI Mingguo1 & LU Xiaoping1,2.1. institute of Geology and geophysics, Chinese Academy of Sciences, P.O. Box 982., Beijing 10002., China 2. Regional Geological and Mineral Resources Survey of Jilin Province, Changchun 130062. China institute of Geology and geophysics Chinese Academy of Sciences Beijing China Regional Geological and Mineral Resources Survey of Jilin Province Changchun China

LA-ICP-MS zircon U-Pb dating indicates that the Bailiping granitic pluton was em-placed during Late Paleozoic to Early Cretaceous (2.5―116 Ma) by four distinct magmatic epi-sodes, arguing against the previous thought that the Bailiping granites were emplaced during Archean, Proterozoic or Early Paleozoic. It is suggested that the so-called Archean Jincheng-dong granite-greenstone belt, mainly composed of Bailiping granites, should be broken down. Sr-Nd isotopic compositions of the Bailiping granites are similar to those of the Phanerozoic granites in the Xing’an-Mongolian orogenic belt, suggesting that their parental magmas were mainly derived from a juvenile crust with some contamination of ancient crustal materials during magma rising and/or emplacement. Therefore, the basement of the Helong Block is similar to that in the northern Xing’an-Mongolian Orogenic Belt, but different from that of the North China Craton. It is proposed that the Archean Jinchengdong complex in this area is probably an exotic slice from the North China Craton, which indicates that the Fu’erhe-Gudonghe Fault, located in northern part of the Helong area, is not the boundary between the North China Craton and the Xing’an-Mongolian Orogenic Belt. The possible boundary should be located further southward more than 50 km and near the Baitoushan volcano.

关键词： LA-ICPMS ziron U-Pb dating, Bailiping complex, Helong Block, North China Craton, Sr-Nd isotope.