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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, {4. 2. Graduate School of the Chinese Academy of Sciences, beijing 100039, {4. 3. College of resources and Environment, Southwest Agricultural University, Chongqing 4.0716, {4. 4. The Ministry of Science and Technology, P. C. {4., beijing 100862, {4. 5. Chengdu institute of Biology, Chinese Academy of Sciences, Chengdu 61004., {4. institute of Geographic Sciences and Natural resources research Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of Sciences Beijing China College of resources and Environment Southwest Agricultural University Chongqing China The Ministry of Science and Technology P. C. China Beijing China Chengdu institute of Biology Chinese Academy of Sciences 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 2000 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 2000, 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 2000, 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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Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South china: Implications for palaeocean temperature

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Progress in Natural Science:Materials International 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1,2, Jiang Shaoyong1, Ling Hongfei1, Yang Jinghong1 and Wan Defan3(1. State Key Laboatory for mineral Deposits research and Center for Marine Geochemistry research, Department of Earth Sciences, Nanjing University, Nanjing 210093, china 2. Tarim Oilfield Company Exploration & Development research institute, Ku’erle 84.000, china 3. institute of mineral resources, Chinese Academy of Geological Sciences, beijing 100037, china) State Key Laboratory for mineral Deposits research Department of Earth Sciences Nanjing University Nanjing 210093 China Exploration and Development research institute Tarim Oilfield Company Ku'erle 841000 China institute of mineral resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South china. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-23). The results showed that the δ30Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 16.8‰ and 17.0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (10.9‰—13.9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (25.4.26.3℃) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

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Southeastern extension of the Red River fault zone (RRFZ) and its tectonic evolution significance in western South china Sea

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Science china Earth Sciences 2006年第8期49卷 839-850页

作者： LIU Baoming1,2,3, XIA Bin1, LI Xuxuan1,3, ZHANG Minqiang1,3, NIU Binhua2, ZHONG Lifeng1, JIN Qinghuan1,4.& JI Shaocheng1,5 1. Key Laboratory of Marginal Sea Geology and resources, Chinese Academy of Sciences,Guangzhou 51064., china 2. china University of Geosciences (beijing), beijing 100083, china 3. research Center of Science & Technology Department, CNOOC, beijing 10002., china 4. Guangzhou Marine Geological Survey, Ministry of Land & resources, Guangzhou 510075, china 5. Ecole Polytechnique Montreal, H3C3A7, Canada Key Laboratory of Marginal Sea Geology and resources Chinese Academy of Sciences Guangzhou China china University of Geosciences (beijing) Beijing China research Center of Science & Technology Department CNOOC Beijing China Guangzhou Marine Geological Survey Ministry of Land & Resources Guangzhou China Ecole Polytechnique Montreal Canada

Recent geophysical surveys and basin modeling suggest that the No.1 fault in the Ying- gehai basin (YGHB) is the seaward elongation of the Red River fault zone (RRFZ) in the South china Sea (SCS). The RRFZ, which separates the South china and Indochina block, extends first along the Yuedong fault, offshore of Vietnam, and then continues southward and breaks off into two branches: the Lupar fault and the Tinjia fault. The southern extension of the Lupar fault dies out beneath the NW Borneo while the Tinjia fault extends southeast and reaches the Brunei-Sabah area. According to the gravity and geomagnetic data, and the tectonic evolution of the basins, there are different evolution histories between the Wan’an basin (WAB) and the basins in the Nansha block. The Tinjia fault may be the boundary between the Balingian block and the Nansha block. Hence, the line linking the Yue- dong fault and the Tinjia fault, which both are continental margin faults and strike-slip ones in the geological evolution histories, constitute the boundary between the Indochina and Nansha block. The Lupar fault, in contrast, is an intraplate fault within the Indochina block. The results provide new hints for reconstructing the tectonic evolution history of the RRFZ and the opening of the SCS, and also a framework for hydrocarbon prospecting in the region.

关键词： Red River fault zone, tectonic evolution, fault, extension, western South china Sea.

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Cesium accumulation by bacterium Thermus sp. TibetanG7:hints for biomineralization of cesium-bearing geyserite in hot springs in Tibet,china

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Chinese Science Bulletin 2007年第19期52卷 2680-2686页

作者： WANG HaiLei1,2,3, ZHENG MianPing1,2,3 & HUANG XiaoXing4.1 institute of mineral resources, Chinese Academy of Geological Sciences (CAGS), beijing 100037, {4. 2 R&D Center for Saline Lake and Epithermal Deposits, CAGS, beijing 100037, {4. 3 Open Laboratory of Saline Lake Resourses and Environment, CAGS, beijing 100037, {4. 4.Laboratory of Microbial resources, institute of Microbiology, Chinese Academy of Sciences, beijing 100081, {4. institute of mineral resources Chinese Academy of Geological Sciences (CAGS) Beijing China R&D Center for Saline Lake and Epithermal Deposits CAGS Beijing China Open Laboratory of Saline Lake Resourses and Environment CAGS Beijing China Laboratory of Microbial resources Institute of Microbiology Chinese Academy of Sciences Beijing China

The bacterium Thermus sp. TibetanG7, isolated from hot springs in Tibet, china, was examined for the ability to accumulate cesium from solutions. Environmental conditions were simulated and the effects of pH, K+, Na+ and K+-regimes were then studied to determine the possible role of the bacterium in the formation of cesium-bearing geyserite around these hot springs. In despite of the inhibition of K+ and Na+, the bacterium Thermus sp. TibetanG7 revealed noticeable accumulation of cesium from solutions, with maximum accumulations of 53.4. and 4..4. μmol Cesium/g cell dry weight in Na+ and K+ inhibition experiments, respectively. The accumulation of cesium by this microorganism is rapid, with 4.%―50% accumulated within the first 5 min. K+-deficient cells showed a much higher capacity of cesium accu- mulation compared with K+-sufficient cells. It is evident that the bacteria within the genus thermus play a significant role in the cesium assembly. The formation of cesium-bearing geyserite is also considered.

关键词：铯元素沉积物硅华生物矿化

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mineralization episode of porphyry copper deposits in the Jinshajiang-Red River mineralization belt: Re-Os dating

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Science china Earth Sciences 2005年第2期48卷 192-198页

作者： WANG Denghong, QU Wenjun, LI Zhiwei, YIN Hanlong4.& CHEN Yuchuan institute of mineral resources, Chinese Academy of Geological Sciences, beijing 100037, {4. National Center of Rock and mineral Analysis, Chinese Academy of Geological Sciences, beijing 100037, {4. Resource Assessment Center of Yunnan, Kunming 650011, {4. institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100101, {4. Chinese Academy of Geological Sciences, beijing 100037, {4. institute of mineral resources Chinese Academy of Geological Sciences Beijing China National Center of Rock and mineral Analysis Chinese Academy of Geological Sciences Beijing China Resource Assessment Center of Yunnan Kunming China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Chinese Academy of Geological Sciences Beijing China

Re-Os isotopic dating for the molybdenites from the porphyry copper deposits of the Jinshajiang-Red River mineralization belt in Yunnan Province yields isochron ages of 33.9±1.1 Ma for the Machangqing deposit and 34.4.0.5 Ma for the Tongchang deposit. This result shows that both the Machangqing and the Tongchang porphyry Cu-Mo deposits from two different ore-fields formed simultaneously. This new data and the published Re-Os model ages of molybdenite (35.4.Ma, 35.9 Ma, 36.2 Ma) of the Yulong porphyry copper deposit in Tibet, which is located in the same Jinshajiang-Red River mineralization belt as the Machangqing deposit and the Tongchang deposit, suggest that these three Cenozoic porphyry copper deposits in the Jinshajiang-Red River mineralization belt were contemporary for their mineralization episode. That is to say, even their present locality is far away and nearly iso-distantly distributed, these three porphyry Cu(Mo) deposits belong to the same mineralization episode at the end of Eocene.

关键词： Re-Os isotopic dating, porphyry Cu deposits, Cenozoic, mineralization episode.

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Response of remotely sensed Normalized Difference Water Deviation Index to the 2006 Drought of eastern Sichuan Basin

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Science china Earth Sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2, GAO ZhiQiang3 & PENG Jian4.1 School of Water Resource and Hydropower, Sichuan University, Chengdu 610065, china 2 National Satellite Meteorological Center, china Meteorological Administration, beijing 100081, china 3 {4. of Geographic Sciences and Natural resources research, Chinese Academy of Sciences, beijing 100101, china 4.School of Environmental Sciences, Peking University, beijing 100871, china School of Water Resource and Hydropower Sichuan University Chengdu China National Statellite Meteorological Center China Meteorological Administration Beijing China institute of Geographic Sciences and Natural resources research Chinese Academy of Sciences Beijing China School of Environmental Sciences Peking University Beijing China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2006 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2001―2006 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2006 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

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Study on real working performance and overload safety factor of high arch dam

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Science china(Technological Sciences) 2008年第S2期51卷 48-59页

作者： ZHANG GuoXin,LIU Yi & ZHOU QiuJing Department of Structures and Materials,china institute of Water resources and Hydropower research,{4. 100038,china Department of Structures and Materials China Institute of Water Resources and Hydropower Research Beijing China

Considering the fact that high arch dams have problems such as complicated stress,high cost,and hazards after being damaged,this paper intends to study the effects of load,material strength,and safety analysis method on dam safety and working performance of arch *** this article,the effects of temperature,self weight exaction way and water loading on structure response are first discussed,and a more reasonable way of considering is then put *** taking into consideration the mechanical property of materials and comparing the effects of different yield criteria on overloading safety of high arch dams,this paper concludes that brittle characteristics of concrete should be fully considered when conducting safety assessment for high arch dams to avoid overestimating the bearing capacity of the *** comparing several typical projects,this paper works out a safety assessment system of multiple safety and relevant engineering analogical analysis methods,which is closer to the actual situation,and thus is able to assess the response of high arch dam structure in a more comprehensive way,elicit the safety coefficients in different situations,and provide a new way of considering the safety assessment of high arch dams.

关键词： high arch dam real working performance safety load strength safety assessment method

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Soil erosion and sediment transport in the gullied Loess Plateau:Scale effects and their mechanisms

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Science china(Technological Sciences) 2009年第5期52卷 1283-1292页

作者： LI TieJian1,WANG GuangQian1,XUE Hai2,3 & WANG Kai4.1 State Key Laboratory of Hydroscience and Engineering,Tsinghua University,beijing 100084.china 2 Yellow River Engineering Consulting Co.,Ltd.,Zhengzhou 4.0003,china 3 North china {4. of Water Conservancy and Hydropower,Zhengzhou 4.0008,china 4.china {4. of Water resources and Hydropower research,beijing 100038,china State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing China Yellow River Engineering Consulting Co. Ltd. Zhengzhou China North china institute of Water Conservancy and Hydropower Zhengzhou China china institute of Water resources and Hydropower research Beijing China

Scale effects exist in the whole process of rainfall-3-runoff-3-soil erosion-3-sediment transport in river basins. The differences of hydrographs and sediment graphs in different positions in a river basin are treated as basic scale effects, which are more complex in the gullied Loess Plateau, a region notorious for high intensity soil erosion and hyper-concentrated sediment-laden flow. The up-scaling method of direct extrapolation that maintains dynamical mechanism effective in large scale application was chosen as the methodology of this paper. Firstly, scale effects of hydrographs and sediment graphs were analyzed by using field data, and key sub-processes and their mechanisms contributing to scale effects were clearly defined. Then, the Digital Yellow River Model that integrates sub-models for the subprocesses was used with high resolution to simulate rainfall-3-runoff-3-soil erosion-3-sediment transport response in Chabagou watershed, and the distributed results representing scale effects were obtained. Finally, analysis on the simulation results was carried out. It was shown that gravitational erosion and hyper-concentrated flow contribute most to the spatial variation of hydrographs and sediment graphs in the spatial scale. Different spatial scale distributions and superposition of different sub-processes are the mechanisms of scale effects.

关键词： scale effect soil erosion hyper-concentrated sediment-laden flow the Loess Plateau

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Combination of drainage, water supply and environmental protection as well as rational distribution of water resource in Zhengzhou mining district

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Science china Earth Sciences 2005年第10期48卷 1768-1779页

作者： WU Qiang1, LI Duo1,2, DI Zhiqiang3, MIAO Ying3, ZHAO Suqi4.& GUO Qiwen5 1. Resource Exploitation Engineering College, CUMT, beijing 100083, china 2. Shijiazhuang Engineering College, University of Economics, Shijiazhuang 050031, china 3. Shenyang institute of Geology and {4. resources, Shenyang 110032, china 4. State Adminstration of Coal Mine Safety, beijing 100013, china 5. Zhengzhou Coal Mine Company (Group), Zhengzhou 4.2371, china Resource Exploitation Engineering College CUMT University of Economics Shenyang institute of Geology and mineral resources State Adminstration of Coal Mine Safety Zhengzhou Coal Mine Company (Group)

The geological condition of coalfield is much complex in china. With increasing in mining depth and drainage amount, the contradiction of drainage, water supply and environ-mental protection is becoming more and more serious. However, the contradiction can be solved by the scientific management of optimizing combination of drainage, water supply and environ-mental protection. The Philip multiple objectives simplex method used in this article has searched for a possible solution at the first step, and then it goes on searching to find out whether there is a weight number that can lead the solution to the biggest. It can reduce the randomness and diffi-culty of traditional weight method which determine the weight number artificially. Some beneficial coefficients are vague and the number is larger in the model of water resource dispatch. So the vague layer analysis method can consider these vague factors fully, combining the qualitative and quantitative analysis together. Especially, this method can quantify the experiential judge-ment of policy decider, and it will turn to be more suitable if the structure of objective factors is complex or the necessary data are absent. In the paper, the two methods above are used to solve the plans of drainage, water supply and optimizing distribution of water resource in the Zhengzhou mining district.

关键词： combination of drainage, water supply and environmental protection, Philip multiple objective simplex method, vague layer analysis method, distribution of water resource.

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Thermodynamics of Cu-Y-I (I=Sn, Zn, Pb) Liquid Solutions

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Journal of Materials Science & Technology 1994年第3期10卷 217-220页

作者： Ting DU and Guodong LI(Central Iron and Steel research institute, Ministry of metallurgical Industry, beijing, 100081, {4.) Central Iron and Steel research Inst Ministry of Metallurgical Industry Beijing China

The isoactivity of [Y] of samples was obtained in multiple- hole graphite crucibles by controlling the oxygen potential through the reaction 2 [Y]+3CO = Y2O3+3C. The activity interaction coefficients between Y and Sn. Zn, Pb alloying elements were determined by using coniugate gradient method of solving ill-conditioned equations. The equilibrium constant of the reaction 2 [Y]+3 [O] = Y2O3 and the standard free energy of formation of Y2O3 in liquid Cu were obtained at 1200℃

关键词： Pb Liquid Solutions I=Sn Thermodynamics of Cu-Y-I Zn I Cu

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