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Gradient analysis of landscape spatial and temporal pattern changes in Beijing metropolitan area

Science China(Technological sciences) 2010年第S1期53卷 91-98页

作者： YANG YeTao1,ZHOU QiMing2.GONG JianYa3 & WANG YingYing4.1 Institute of Geophysics and Geomatics,China university of {2.,wuhan 4.0074.China 2.Department of Geography,Hong Kong Baptist university,Hong Kong 3 State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,wuhan university,wuhan 4.0074.China 4.Hubei Provincial Bureau of Meteorology,wuhan 4.0074.China 1. Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China2. Department of Geography Hong Kong Baptist University Hong Kong China3. State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430074 China4. Hubei Provincial Bureau of Meteorology Wuhan 430074 China

The gradient based landscape metrics analysis is now widely used to study the landscape pattern changes in respond to the *** order to discover the trend of spatio-temporal changes in Beijing metropolitan area during the past 15 years,several landscape metrics are computed using a moving window along a 96 km long transect across Beijing metropolitan area from west to ***,the spatial extent of sub-landscape,which is determined by the moving window’s size,is profoundly *** results show that the metrics varies smoothly and regularly along the selected transect when the window size is greater than 6 km×6 km,and irregularly fluctuated for the smaller window size,that the spatial and temporal landscape characteristics of Beijing city match the hypothetical framework of spatio-temporal urban sprawl in the form of alternating processes of diffusion and coalescence well,and that some new trends of the urban sprawl style in Beijing metropolitan area,such as leap-frog manner,are also detected by the gradient landscape analysis.

关键词： gradient analysis landscape metrics spatio-temporal urban expansion multi-extent

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Weathered Mantle Hosted Gold Deposit atShewushan, Hubei, Central China

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Journal of China university of geosciences 2001年第1期12卷 60-67页

作者： Hong Hanlie Wang Qinyan The Center for Material Research and Testing, wuhan university of Technology, wuhan 4.0070 Bian Qiujuan faculty of {4. sciences, China university of geosciences, wuhan 4.0074 The Center for Material Research and Testing Wuhan University of Technology faculty of earth {2. China University of Geosciences

A supergene gold deposit is located at Shewushan, south Hubei, Central China. The Au mass fraction of the supergene deposits ranges from 1.0.10-6 to 19.5 10-6, with an average of about 2.2.10-6. Primary gold mineralization is closely associated with the well developed faults and fractures mainly on the crest of the reverse anticline with gold mass fraction exceeding1.0 X 10-6(average 0.6 X 10-6 ), the gold occurs as small Ag-bearing particles in association with illite and kaolinite, and partly incorporated within the lattice of pyrite. Fluid inclusion studies on the gold mineralization yield trapping temperatures and pressures from 110 to 2.0 and 4.0 105 to 4.0 105 pa, respectively. The salinities of mineralization fluids range from 2. 6 % to 8. 4.% w(NaCl, equivalent). Calculated (18O) values and measured (D) data of the hypogene fluids indicate a meteoric origin. These fluids underwent extreme 18 O enrichment by reacting with country carbonate rock. Supergene gold minerali- zation is confined largely to the lower portion at the weathered mantle; the gold occurs as small native gold particles accompanied by clay minerals, kaolinite and illite and Mn and Fe oxides. Geochemical investigation shows that Au, together with As and Sb, decreases progressively from the top of ore body to some 2.kilometers away and define a lateral dispersion halo. It is proposed that the gold is mobilized by surficial leaching and concentrated at the lower portion of the weathering profile, and thio-sulfate may play an active role in gold dissolution and re-precipitation.

关键词： gold deposit weathering inclusion temperature stable isotopes Shewushan.

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Electroluminescent properties of three ternary europium complexes with different phenanthroline derivatives

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Science China Chemistry 2004年第4期47卷 326-334页

作者： BIAN Zuqiang1,2. GAO Deqing1, GUAN Min1, XIN Hao1, LI Fuyou1, HUANG Chunhui1, WANG Kezhi2.& JIN Linpei2.1. State Key Laboratory of Rare earth Materials Chemistry and Applications, Peking university, Beijing 100871, China 2. Department of Chemistry, Beijing Normal university, Beijing 100875, China 1. State Key Laboratory of Rare earth Materials Chemistry and Applications Peking University 100871 Beijing China 2. Department of Chemistry Beijing Normal University 100875 Beijing China

Three ternary Eu(III) complexes with general formula of Eu(DBM)3LN (DBM = dibenzoylmethanate, and LN (N = 1-3 ) stand for three different 1,10-phenanthroline derivatives) have been synthesized for vacuum deposition films-based electroluminescent devices. The complex Eu(DBM)3L3 (L3 = 2.phenyl-3-[3-(carbazol-9-yl)propyl]imidazo[4.5-f]1,10-phenan-throline) was designed with an effort to combine the electron-transporting phenanthroline platform and the hole-transporting carbazole group into one molecule expecting to improve both electron and hole transporting properties simultaneously. The results show that the variation of the neutral ligands in Eu(III) mixed ligand complexes is a simple and effective approach to the improvement in the thermal stability, PL and EL properties of materials. A double-layer device with the configuration of ITO/TPD (50 nm)/Eu(DBM)3L3 (50 nm)/Mg0.9Ag0.1 (2.0 nm)/Ag (100 nm) exhibited Eu(III)-based pure red emission with a maximum brightness of 561 cd/m2.at 16 V, and an onset driving voltage of 8 V. A device with the configuration of ITO/TPD (50 nm)/[Eu(DBM)3L3 (5 nm):BCP (5 nm)]4.BCP (2. nm)/AIQ (10 nm) Mg0.9Ag0.9 (110 nm)/Ag (100 nm) gave high efficient and pure red light emission with a luminance of 14.9 cd/m2. Keywords dibenzoylmethane - electroluminescence - lanthanide - N ligands

关键词： dibenzoylmethane electroluminescence lanthanide N ligands

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Effect of climatic change on snowmelt runoffs in mountainous regions of inland rivers in Northwestern China

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Science China earth sciences 2006年第8期49卷 881-888页

作者： WANG Jian1 & LI Shuo2.1. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of sciences, Lanzhou 730000, China 2. College of Geography, Nanjing Normal university, Nanjing 2.0097, China 1. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. College of Geography Nanjing Normal University Nanjing 210097 China

Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern China. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2.01. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4. were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4. warming scenario.

关键词： climatic changes, snowmelt runoff, SRM model, upper Heihe Watershed, simulating.

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Organic Geochemistry Characteristics in Ores and Host Rocks from Qixiashan Lead-Zinc Deposit, Nanjing, China

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Journal of China university of geosciences 2003年第2期14卷 127-136页

作者： Xie Shucheng Wang Hongmei Guo Jianqiu Liang Bin Zhou Xiugao faculty of earth {2., China university of {4., wuhan 4.0074 faculty of earth {2. China University of Geosciences Wuhan 430074

Organic matter, associated with ores, host rocks, ore source rocks and present in fluid inclusions in the Qixiashan lead zinc polymetallic deposit hosted in Upper Carboniferous dolomites and limestones in East China, was systematically analyzed using Fourier transform infrared spectroscopy, gas chromatography (GC), GC/mass spectrometry and proton induced X ray emission. The biomarker ratios of n C - 2. / n C + 2. alkanes, C 2. tricyclic/C 30 hopane and the tricyclic terpane parameters including C 2. /C 2. , C 19-2. /C 2.-2. and C 19-2. /C 2.-2. can effectively discriminate ores from host rocks. Extractable organic matter present in fluid inclusions displays similarities to those enclosed in the ore source rocks in the biomarker ratios, suggesting that a proportion of organic matter was introduced into the deposit from the ore source strata. The presence of copper and zinc in stage Ⅱ pyrobitumen indicates that some metals may have been transported by an organic fluid or removed from an aqueous fluid by organic matter.

关键词： biometallogenesis biomineralization mineral deposit molecular fossil.

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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 Academy of sciences, Beijing 100101, China 2. Graduate School of the Chinese Academy of sciences, Beijing 100039, China 3. College of Resources and Environment, Southwest Agricultural university, Chongqing 4.0716, China 4. The Ministry of Science and Technology, P. C. China, Beijing 100862. China 5. Chengdu Institute of Biology, Chinese Academy of sciences, Chengdu 61004., China 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese Academy of sciences 100039 Beijing China 3. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and Technology P. C. China 100862 Beijing China 5. Chengdu Institute of Biology Chinese Academy of Sciences 610041 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 9.4.%. 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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Soil Loss by Wind Erosion for Three Different Textured Soils Treated with Polyacrylamide and Crude Oil, Iraq

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Journal of China university of geosciences 2001年第2期12卷 113-116页

作者： Mushtak Talib Jabbar faculty of earth Resources, China {2. of geosciences, {4. 4.0074 faculty of earth Resources China University of Geosciences

The study is conducted to estimate the resistance of three soils (EL Hartha clay loam, Barjisiya sandy loam and the soil near the sand dunes in Sheikh sa'ad area sandy soil) to wind erosion, it is also aimed at getting full acquaintance of the relationship between the soil loss and the physical and chemical features of soil. In addition to the experiment of some soil stabilizers, polyacrylamide (PAM) concentration of 0.2.% and crude oil in concentration of 1 % in order to reduce or prevent wind erosion. The study shows that the amendment increased the dry soil aggregate >1 mm, mean weight diameter and soil moisture. It is clear that polyacrylamide had greater effect than that of crude oil, besides the great effectiveness of these amendments in decreasing bulk density and relations of soil loss.

关键词： three location in Iraq stabilizers wind erosion soil physical properties.

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Hydrocarbon Accumulation Condition and Exploration Direction in the Deepwater Area of Qiongdongnan Basin,Northern South China Sea

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地学前缘 2009年第S1期16卷 147-148页

作者： Jun Xiao,Hua Wang,Hua Jiang faculty of earth Resources,China {2. of geosciences({4.),{4. 4.0074.China.

The deepwater area of southern Qiongdongnan Basin is a hydrocarbon exploration frontier and mainly located on the continental slope in the northwestern South China *** tectonic and depositional evolution is similar to the typical marginal deepwater areas abroad where oils have been *** hydrocarbon conditions in this area are as follows:(1) three sets of source rocks (including lacustrine mudstone of Eocene,coastal plain coal-bearing strata and semi-closed shallow sea mudstone of Oligocene,and marine mudstone

关键词： Qiongdongnan Basin deepwater area condition of hydrocarbon reservoir forming hydrocarbon exploration

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Retrogressive Microstructures: A Key to Post-Collisional Uplift and Extension Tectonics of Ultrahigh-Pressure Metamorphic Rocks from Dabie Orogenic Belt, China

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Journal of earth Science 1999年第3期18卷 200-206页

作者： You Zhendong Suo Shutian Zhong Zengqiu Zhang Zeming Wei Bize(faculty of earth {2., China university of {4., wuhan 4.0074. faculty of earth {2. China University of Geosciences Wuhan 430074

A wealth of retrogressive microstructures have been discovered from the UHP metamorphic rocks in Dabie orogenic belt, namely, the ultrahigh-pressure (URP) eclogites, jadeite quartzites and kyanite-zoisite-quartz vein. The most important are pseudomorphic replacements of UHP minerals like coesite, the corona reaction textures iuduced by solid-solid reactions as well as the corona and symplectites induced by reactions involving fluid. According to the textural relationships the sequence of mineral Paragenesis and the metamorphic stages in the UHP eclogites can be delineated; the mineral geobarothermometry of the various stages of retrograde metamorphism is studied and a clockwise, nearly isothermal decompressive metamorphic PT-trajectory for the UHP eclogites can be reconstructed. In terms of the PT-trajectory the two stage post collision uplirt and exhumation processes are reflected. When the UHP metumorphic rocks extruded to the lower-middle crust partial melting happened which bad in turn caused tke crustal extension and the further exhumation or the UHP metomorphic rocks. Based on the field strain analysis combined with geochronological data a scenario or post collision uplift aud exhumation model is presented.

关键词： retrogressive microstructure ultrahigh-pressure metamorphism Dabie orogenic belt

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A Comparison about Metamorphism among the Oldest-Rock Units from Orogenic Belts of Dabie,Eastern Qinling and Eastern Kunlun of Central Mountain Ranges,China

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Journal of earth Science 1998年第3期17卷 10-15页

作者： Chen Nengsong Zhang Kexin Wang Guocan Hou Guangjiu Zhu Yunhai faculty of earth {2., China university of {4., wuhan 4.0074

The Dabie orogen, Eastern Qinling orogen and Eastern Kunlun orogen are the major components of the Central Mountain Ranges of China and each has distinctively metamorphic processes in their oldest rock units. The Dabie orogen oldest rock units had experienced an intermediate-higher pressure, upper amphibolite to lower granulite facies metamorphism in the Indosinian intracontinental subduction collision event. The clockwise pt path, synchronous attainment of t max and p max and a segment of high slope retrograde path suggest a tectono driven rapid exhumation of the oldest rock units to upper middle crustal level following the end of the subduction collision process. The oldest rock units, also called Qinling Group, of Eastern Qinling Mountains suffered intensively collisional metamorphism at an immature plate tectonic framework during Jinningian movement about 1 000 Ma ago. The clockwise pt path with reach of t max following several hundreds of MPa decreasing from p max suggests that the denudation of the deeply burial rock units was due essentially to isostatic relaxation. During the Caledonian stage, the highly metamorphosed oldest rock units suffered from a high t thermal event in arc environment and superimposed by contact metamorphism. After thermal peaks, the rock units were exhumed in a short distance and cooled down isobarically. No regional metamorphism higher than upper greenschist facies condition since 300 Ma has been traced within exposed rocks in the eastern portion of Northern Qinling orogen. The oldest rock units in the Eastern Kunlun orogen were metamorphosed to upper amphibolite facies to lower granulite facies rocks early or during the Luliang movement (some 1 800 Ma ago). The high grade metamorphic rock units had a long resident time at the deep crustal level, and were exhumed to middle upper crustal level during the Caledonian to Hercynian tectonometamorphic events. Shallow erosion of

关键词： the oldest metamorphic rock units pt path geodynamics of metamorphism Dabie orogen Eastern Qinling orogen Eastern Kunlun orogen Central Mountain Ranges of China.

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