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Chronological record of the Early Mesozoic underplating in the northern margin of North china—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2**) Zhang Hongfu~2 Liu Xiaoming~3 Li Zhitong~4 (1.School of Earth and Space sciences,Peking University,beijing 100871,china 2.institute of Geology and Geophysics and Key Laboratory of Mineral resources,Chinese Academy of sciences,beijing 100029,china 3.Key Laboratory of Continental Dynamics,Northwestern University,Xi'an 710069,china 4.institute of Geology and Mineral resources of Shenyang,Shenyang 110032,china) [a]School of Earth and Space sciences Peking University Beijing China [b]Laboratory of Mineral resources Chinese Academy of Sciences Institute of Geology and Continental Dynamics Beijing China [c]Key Laboratory of Continental Dynamics Northwestern university Xi'an China [d]institute of Geology and Mineral resources of Shenyang Shenyang China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 254 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North china Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

Remote sensing based shrub above-ground biomass and carbon storage mapping in Mu Us desert,china

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Science china(Technological sciences) 2010年第S1期53卷 176-183页

作者： XU Min 1,2,CAO ChunXiang 1,TONG QingXi 1,LI ZengYuan 3,ZHANG Hao 1,HE QiSheng 1,2,GAO MengXu 1,2,ZHAO Jian 1,2,ZHENG Sheng 1,2,CHEN Wei 1,2 & ZHENG LanFen 1 1State 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 School of the Chinese Academy of sciences,beijing 100049,china 3 research institute of Forest resources and Information Techniques,Chinese Academy of Forestry,beijing 10009,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 School of the Chinese Academy of sciences Beijing 100049 China 3. research institute of Forest resources and Information Techniques Chinese Academy of Forestry Beijing 10009 China

The estimation of above-ground biomass(AGB) and carbon storage is very important for arid and semi-arid ***-1A/B satellite data combined with field measurement data was used for the estimation of shrub AGB and carbon storage in the Mu Us desert,*** correlations of shrub AGB and spectral reflectance of four bands as well as their combined vegetation indexes were respectively analyzed and stepwise regression analysis was employed to establish AGB prediction *** prediction equation based on ratio vegetation index(RVI)was proved to be more suitable for shrub AGB estimation in the Mu Us desert than *** AGB and carbon storage were mapped using the RVI based prediction model in *** statistics showed the western Mu Us desert has relatively high AGB and carbon storage,and that the gross shrub carton storage in Mu Us desert reaches 16 799 200 t,which has greatly contributed to the carbon fixation in northern china.

关键词： above-ground biomass carbon storage Mu Us desert HJ-1A/B remote sensing

A new iguanodontid (Jin-zhousaurus yangi *** ***.) from the Yixian Formation of western Liaoning,china

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Chinese Science Bulletin 2001年第19期46卷 1669-1672页

作者： WANG Xiaolin & XU Xing1. institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of sciences, beijing 100044, china 2. College of Earth sciences and resources, china University of Geo-sciences, beijing 100083, china institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China College of Earth sciences and resources China University of Geosciences Beijing China

A new iguanodontid, Jinzhousaurus yangi gen. et sp. nov., is erected based on the cranial and dental morphology of a specimen from the Yixian Formation of western Liaoning. Although a few primitive characteristics remain, Jinzhousaurus yangi display a number of characteristics similar to those seen in derived iguanodontids. Other interesting characteristics include the absence of antorbital fenestra and the frontal excluded from the participation in orbit, which are closer to the condition in hadrosaurids. The unusual combination of the characteristics provides important data for assessing morphological evolution toward hadrosaurs. The new discovery also represents the first reported large-sized dinosaur from Jehol fauna in western Liaoning, and increases the diversity of this famous fauna. Furthermore, the discovery of a derived iguanodontid from the Yixian Formation provides further evidence supporting a Cretaceous age of the Jehol fauna, which is consistent with an isotopic age.

关键词： Western Liaoning Lower Cretaceous Yixian Formation Jehol Biota Iguanodontid

Seasonal Changes of a and Pmax on Tibetan Plateau Alpine Meadow Ecosystem

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Seasonal Changes of a and Pmax on Tibetan Plateau Alpine Mea...

Petrogenesis and dating of the Kangding complex,Sichuan Province

第四届青藏高原国际学术研讨会

作者： Xu Lingling Zhang Xianzhou Li Shipei institute of geographical sciences and natural resources research, beijing 100101, china

The Alpine meadow is one of the vegetation types widely distributed on the Tibetan Plateau with the area about 1.2 million square kilometers. The dangxiong grass station located in hinterland of Tibetan Plateau is covered with this typical vegetation. The continuous carbon flux data measured with the open-path eddy covariance systems during growing season in 2003 were used to analyze the diurnal variation patterns of the Net Ecosystem carbon dioxide Exchange (NEE) and the seasonal changes of its apparent quantum yield αas well as maximum ecosystem assimilation P. Results showed that the Net Ecosystem carbon dioxide Exchange presented obvious diurnal variation patterns with single-peak of diurnal maximum carbon assimilation at 11: 00-12: 00 (local time).The diurnal maximum carbon assimilation was highest in exuberance period (-0.288 mg COms i.e.-6.538μmol COms) and lowest in withering period (-0.18mg COms i.e.-4.086μmol COms). During the daytime, NEE fitted fairly well with PAR in a rectangular hyperbola function, with apparent quantum yield declining in the order of exuberance period (0.0244μmolCO μmol PAR) >early exuberance period >seed maturing period > withering period (0.0098μmolCO μmol PAR). The maximum ecosystem assimilation didn’t change much during the first three period with an average of 0.433 mgCOms i.e.9.829μmolCOms. But during withering period, it was only 0.35 mg COms i.e.7.945μmolCOms.

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Science china Earth sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3 1. Faculty of Earth sciences and natural resources, china University of Geosciences, beijing 100083, china 2. Faculty of Earth sciences, china University of Geosciences, Wuhan 430074, china 3. beijing SHRIMP Center, institute of Geology, Chinese Academy of Geological sciences, beijing 100037, china 1. Faculty of Earth sciences and natural resources China University of Geosciences 100083 Beijing China 2. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China 3. beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 721 and 773 Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2468 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

A Study on Policy Demands and Designing Principles of Strategy of Dominant Function Zoning

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china City Planning Review 2008年第3期17卷 18-23页

作者： SI Jinsong,institute of geographical sciences and natural resources research,Chinese Academy of sciences,beijing,P.R.china.

In china’s Outline of the 11th Five-year Plan for National Economic and Social Development , Dominant Function Zoning was put forward as a

关键词： formulated balanced match rational concerned local

Estimation of soil organic carbon reservoir in china

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Journal of geographical sciences 2001年第1期11卷 3-13页

作者： WANG Shao-qiang1, ZHOU Cheng-hu1, LI Ke-rang1, ZHU Song-li2, HUANG Fang-hong1 (1.The State Key Laboratory of resources and Environment Information System, institute of Geographic sciences and natural resources research, cas, beijing 100101, china The State Key Laboratory of resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research CAS Beijing China institute of Environment Science Beijing Normal University Beijing China

The paper respectively adopted physio-chemical properties of every soil stratum from 2473 soil profiles of the second national soil survey. The corresponding carbon content of soils is estimated by utilizing conversion coefficient 0.58. In the second soil survey, the total amount of soil organic carbon is about 924.18xl08t and carbon density is about 10.53 kgC/m2 in china according to the area of 877.63x106hm2 surveyed throughout the country. The spatial distribution characteristics of soil organic carbon in china is that the carbon storage increases when latitude increases in eastern china and the carbon storage decreases when longitude reduces in northern china. A transitional zone with great variation in carbon storage exists. Moreover, there is an increasing tendency of carbon density with decrease of latitude in western china. Soil circle is of great significance to global change, but with substantial difference in soil spatial distribution throughout the country. Because the structure of soil is inhomogeneous, it could bring some mistakes in estimating soil carbon reservoirs. It is necessary to farther resolve soil respiration and organic matter conversion and other questions by developing uniform and normal methods of measurement and sampling.

关键词： terrestrial ecosystem global change soil carbon reservoir carbon cycle

Ecological response to the climate change on the northern slope of the Tianshan Mountains in Xinjiang

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Science china Earth sciences 2005年第6期48卷 765-777页

作者： CHEN Xi1, LUO Geping1, XIA Jun2, ZHOU Kefa1, LOU Shaoping3 & YE Minquan4 1. Xinjiang institute of Ecology and Geography, Chinese Academy of sciences, Urumqi 830011, china 2. institute of geographical and resources sciences, Chinese Academy of sciences, beijing 100101, china 3. Urumqi Meteorological-satellite Land Station, Urumqi 830011, china 4. Seismological Bureau of Xinjiang Uygur Autonomous Region, Urümqi 830011, china Correspondence should be addressed to Chen Xi 1. Xinjiang institute of Ecology and Geography Chinese Academy of Sciences 830011 Urumqi China 2. institute of geographical and resources sciences Chinese Academy of Sciences 100101 Beijing China 3. Urumqi Meteorological-satellite Land Station 830011 Urumqi China 4. Seismological Bureau of Xinjiang Uygur Autonomous Region 830011 Urümqi China

The Tianshan Mountains is a high and huge mountain body lying across the central part of Xinjiang, china, and is also the main area where the runoff forms in Xinjiang. In this paper, a set of RS-based study methods is put forward for deriving the information about the natural change of the ecology in arid areas, and the relationship between the climate change trend and the corresponding ecological response on the northern slope of the Tianshan Mountains since recent 40 years is analyzed from the scales of the land cover ecosystems and landscapes based on the observed data of climate, hydrology, modern glaciers and lakes on the northern slopes of the Tianshan Mountains since recent 40 years and the satellite RS data since recent 10 years by using the RS and GIS technologies. The results are as follows: (1) The overall trend of climate change on the northern slope of the Tianshan Mountains since recent 40 years is that both air temperature and precipitation are increased, especially the increase amplitudes of air tempera-ture, precipitation and annual runoff volume are high since the decade of the 1990s; (2) the in-tegrated indexes of the vegetation in all the geographical divisions on the northern slope of the Tianshan Mountains are obviously increased since recent 10 years, especially in the artificial oases and the foothill belts, such a change trend is advantageous for improving the vegetation ecology; and (3) the vegetation ecology in the arid areas is extremely sensitive to the climate change, the vegetation coverage and the biomass on the northern slope of the Tianshan Moun-tains are continuously increased because of the climate change since recent 10 years, their in-crease amplitudes in the plains and during the late stage are obviously higher than that in the mountainous regions and during the early stage.

关键词： north slope of the Tianshan Mountains, climate change, hydrological change, natural change of ecology,RS and GIS, vegetation index.

The challenge of wide application of information and communication technologies to traditional location theory

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Journal of geographical sciences 2013年第2期23卷 315-330页

作者： SONG Zhouying LIU Weidong Key Laboratory of Regional Sustainable Development Modeling of the Chinese Academy of sciences institute of Geographic sciences and natural resourcesResea—rch CASBeijing100101China

The wide application of information and communication technologies （ICTs） has been argued to be critical to spatial transformation of firms. Recent advances in the studies along this line have challenged traditional location theory. The existing literature, however, focuses mainly on the impacts of ICTs on Iocational conditions and industrial spatial distribution. The dynamics behind such changes have not yet been given sufficient attention by geographers. Given this background, this paper investigates the impact of new ICTs on traditional location theory and the dynamics of industrial re-location that are enabled by new ICTs, based on data collected from an investigation of 178 firms. The paper argues that the application of new ICTs has been a key location factor in the information age, and that the time-cost is becoming critical to the spatial organization of firms, particularly as a result of a shorter product life and mass customization, among other dynamics.

关键词： information and communication technologies location factor time-cost