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Aoyitake plagiogranite in western Tarim Block, NW China: Age, geochemistry, petrogenesis and its tectonic implications

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Science China Earth Sciences 2006年第11期49卷 1121-1134页

作者： ZHANG Chuanlin1,2, YU Haifeng3, YE Haimin2, ZHAO Yu2 & ZHANG Dongsheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 2. Nanjing institute of Geology and Mineral resources, Nanjing 210016, China 3. Tianjin institute of Geology and Mineral resources, Tianjin 300170, China 4. The 2nd Regional Geological Investigation Party, Xinjiang Bureau of Geology and Mineral resources, Changji 831100, China Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Nanjing institute of Geology and Mineral resources Nanjing China Tianjin institute of Geology and Mineral resources Tianjin China The 2nd Regional Geological Investigation Party Xinjiang Bureau of Geology and Mineral Resources Changji China

SHRIMPP U-Pb zircon age and geochemical and Nd isotopic data are reported for the Aoyitake plagiogranite in western Tarim Block, NW China. The plagiogranite intruded the Middle Pro- terozoic and Lower Carboniferous with an exposure area of ca. 60 km2 and crystallized at 330.7±4.8 Ma. Rock types mainly include tonalite, trondhjemite and minor amounts of diorite and quartz-diorite. Feldspars in the rocks are dominated by oligoclase-andesine, and minor perthite observed locally. The granites are sodic with Na/K ratios (molar) between 4 and 87. Total REE (50-220 ppm) show a clear positive correlation with SiO2. There is no LRRE/HREE fractionation (LaN/YbN=0.5-1.5), me- dium negative Eu anomalies (δ Eu=0.3-0.6), high Y content and low Sr/Y ratio (~1.0). These granites exhibit relatively juvenile Nd T2DM model ages of 470 to 580 Ma and positive εNd(331 Ma) values of 6.23 to 7.65. The aforementioned characteristics are similar to those of ocean island or ocean ridge plagiogranites. However, the regional geology, especially its scale, precludes that the plagiogranite pluton was derived directly from fractionational crystallization of mantle-derived basaltic magma. We interpreted that the primary magma of the pluton might be tonalitic in composition generated by ca. 50% partial melting of the juvenile basaltic crust. The primary magma experienced intensive frac- tionational crystallization, and intruded into the middle to upper crusts to form the granite pluton. In combination with the previous regional geological data, it is concluded that the plagiogranite pluton was emplaced within the Tarim Block in respond to the Carboniferous continental rifting along the Tianshan orogenic belt.

关键词： western Tarim, Aoyitake plagiogranite, age, geochemistry, tectonic implications.

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Response of Biomass Spatial Pattern of Alpine Vegetation to Climate Change in Permafrost Region of the Qinghai-Tibet Plateau,China

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Journal of Mountain Science 2010年第4期7卷 301-314页

作者： ZHANG Yu WANG Genxu WANG Yibo College of resources & environment Lanzhou UniversityLanzhou 730000China institute of Mountain Hazards and environment Chinese Academy of SciencesChengdu 610041China

Alpine ecosystems in permafrost region are extremely sensitive to climate *** determine spatial pattern variations in alpine meadow and alpine steppe biomass dynamics in the permafrost region of the Qinghai-Tibet Plateau,China,calibrated with historical datasets of above-ground biomass production within the permafrost region's two main ecosystems,an ecosystem-biomass model was developed by employing empirical spatialdistribution models of the study region's precipitation,air temperature and soil *** model was then successfully used to simulate the spatio-temporal variations in annual alpine ecosystem biomass production under climate *** a 0.44°C decade-1 rise in air temperature,the model predicted that the biomasses of alpine meadow and alpine steppe remained roughly the same if annual precipitation increased by 8 mm per decade-1,but the biomasses were decreased by 2.7% and 2.4%,respectively if precipitation was *** a 2.2°C decade-1 rise in air temperature coupled with a 12 mm decade-1 rise in precipitation,the model predicted that the biomass of alpine meadow was unchanged or slightly increased,while that of alpine steppe was increased by 5.2%.However,in the absence of any rise in precipitation,the model predicted 6.8% and 4.6% declines in alpine meadow and alpine steppe biomasses,*** response of alpine steppe biomass to the rising air temperatures and precipitation was significantly lesser and greater,respectively than that of alpine meadow biomass.A better understanding of the difference in alpine ecosystem biomass production under climate change is greatly significant with respect to the influence of climate change on the carbon and water cycles in the permafrost regions of the Qinghai-Tibet Plateau.

关键词： Permafrost change Qinghai-TibetanPlateau Alpine ecosystem Grassland biomass Climate change Response model

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Sequential Extraction of Natural Surface Coatings: Comparison with Single Stage Extraction and Its Application in Investigating Adsorption Characteristics of Surface Coating Components for Metals

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Chemical Research in Chinese Universities 2012年第1期28卷 41-46页

作者： HUA Xiu-yi, LIU Xiao-xue, DONG De-ming, LI Ming and LI Yao-rui Key Laboratory of Groundwater resources and environment, Ministry of Education, Key Lab of Water resources and Aquatic environment of Jilin Province, College of environment and resources, Jilin University, Changchun 130012, P. R. China College of environment and resources Jilin University Key Laboratory of Groundwater Resources and Environment Ministry of Education Key Lab of Water resources and Aquatic environment of Jilin Province Changchun 130012

Multistage sequential extraction with different sequences was applied to extracting natural surface coa tings（NSCs）, and the results were compared with those by single stage extraction technique. The optimal sequential extraction scheme with the best performance was selected and incorporated into the method of selective extraction followed by adsorption and statistic analyses to study the adsorption parameters of Fe oxides, Mn oxides and organic matters in NSCs for Pb and Cd, to validate the applicability of the sequential extraction scheme. The Langmuir ad sorption parameters of each component of surface coating estimated according to the adsorption data of single stage extraction of NSCs were all similar to those of sequential extraction of NSCs, and the maximum difference between the metal adsorption abilities of the components estimated via the two extraction techniques was only about 20%, in dicating that either extraction techniques could be used. The optimal sequential extraction scheme obtained was first extracted with NH2OH·HCl, then with Na2S2O4, and finally with oxalic acid.

关键词： Natural surface coating(NSC) Sequential extraction Single stage extraction Adsorption Component

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Human activity response and prevention strategies on soil and water loss in Sichuan Province

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Science China(Technological Sciences) 2003年第Z1期46卷 91-109页

作者： FANG Yiping & CHEN Guojie institute of Mountain Hazards and environment, Chinese Academy of Sciences and Ministry of Water resources, Chengdu 610041, China Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water resources Chengdu 610041 Peoples R China

Ten major factors have been selected to judge the degree of disturbance from human activity and the corresponding relationship of the impact on soil and water loss in Sichuan Province. Correlation analysis has demonstrated that stock-carrying capacity, percentage of land reclamation, population density, GDP per capita, mineral modulus and percentage of forest coverage are the 6 most relevant human activity factors. The analysis on the degree of disturbance has shown that population pressure, excessive or unreasonable activities in development of resources and destructive behavior of humans are the main causes of soil and water loss. Consequently, solving the various problems in the negative activity of humans and regulating human behavior are the first tasks that should be tackled in the conservation of water and soil. In the new era, the prevention and rectification of soil and water loss are measures based on the foundation of the ecosystem, which is a kind of management strategy for sustainable development. The foundation of this method is made up of the system innovations and breakthroughs in terms of aims, philosophy, measures, and aspects of the prevention and rectification of soil and water loss, simultaneous advance from the conceptual, policy, spatial, technical and mode levels and system integration on the treatment strategies.

关键词： Sichuan, degree of disturbance, soil and water loss, system innovation.

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Emission Patterns under Alternative Congestion and Motor Vehicle Pollution Mitigation Policies in Shanghai

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Chinese Journal of Population,resources and environment 2007年第2期5卷 41-48页

作者： Chen Hongfeng1, Li Fen1, Li Xiangling2 1. School of environment and Natural resources, Renmin University of China, Beijing 100872, China 2. School of Natural resources and environment, Hefei University of Technology, Hefei Anhui 230009, China School of environment and Natural resources Renmin University of China Beijing 100872 China School of Natural resources and environment Hefei University of Technology Hefei Anhui 230009 China

As a megacity with thriving economy, Shanghai is experiencing rapid motorisation and confronted with traffic congestion problems despite its low car ownership. It is of value to look into the policies on emission control of motor vehicle and congestion reduction in such a city to explore how to reconcile mobility enhancement with the environment. Results of a dynamic simulation displayed time paths of emissions from motor vehicles in Shanghai over the period from 2000 to 2020. The simulation results showed that early policies on emission control of motor vehicle could bring about far-reaching effects on emission reduc- tion, and take advantage of available low-polluting technologies and technical innovation over time. Travel demand management would play an important role in curbing congestion and reducing motor vehicle pollution by calming down car ownership rise and deterring inefficient trips as well as reducing fuel waste caused by congestion.

关键词： dynamic simulation motorisation motor vehicle emission traffic congestion travel demand management low-polluting technologies

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Carbon and Oxygen Stable Isotope Values and Microfossils at 41.4-4.5ka BP in Tai Co,Tibet,China,and Their Paleoclimatic Significance

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1036-1050+1052-1056+1051页

作者： ZHENG Mianping~(1,2,*),LIU Junying~(1,3),MA Zhibang~(1,4),WANG Hailei~(1,2) and MA Nina~(1,2) 1 MLR Key Laboratory of Saline Lake resources and environment,institute of Mineral resources,CAGS, Beijing 100037,China 2 Research and Development Center for Saline Lakes and Epithermal Deposits,Chinese Academy of Geological Sciences,Beijing 100037,China 3 institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China 4 Key Laboratory of Cenozoic Geology and environment,Chinese Academy of Sciences,Beijing 100029, China MLR Key Laboratory of Saline Lake resources and environment Institute of Mineral Resources CAGS Beijing 100037 China Research and Development Center for Saline Lakes and Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Key Laboratory of Cenozoic Geology and environment Chinese Academy of Sciences Beijing 100029 China

Two sedimentary sections were measured at Tai Co(Co means lake in Tibetan) in western Tibet,*** two sections are almost all composed of clay carbonate beds except in their lower parts where there are carbonized plants at>10 cm depths and dark-colored carbonate clay and clay at 50-70 cm depths,yielding abundant gastropods,ostracods,and *** carbon and oxygen stable isotope values of carbonate,ostracods,and charophytes and ecological features of microfossil communities indicate the following climatic change in the area from 41.4 to 4.5 ka BP:at 41.4-26.2 ka BP,the climate was relatively wet;at 26.2-25.5 ka BP,it was slightly warm-dry;at 25.5-22.5 ka BP,it was warm-wet;at 22.5-21.0 ka BP,it was slightly cold-wet;at 20.5-17.5 ka BP,it became cold abruptly and slightly wet,implying the climate of the last glacial maximum;at 17.5-16.0 ka BP,it was slightly cold-dry;at 16.0-11.8 ka BP,it was slightly warm-wet;at 11.8-10.4 ka BP,it was relatively cold-dry, roughly equivalent to the climate of the Younger Dryas,and at 10.4 ka BP,the temperatures began to rise again;at 10.4-9.4 ka BP,it was slightly warm-wet;at 9.4-8.5 ka BP,there occurred short warm-wet oscillations;at 8.5-7.9 ka BP,it was slightly dry-cold,representing a strong temperature-lowering and drying event in the postglacial stage;at 7.8-6.3 ka BP,it was slightly warm-wet;at 6.3-4.5 ka BP,the climate tended to be cold-dry.4.5 ka BP recorded the maximum aridity since the late part of the late Pleistocene.

关键词： sedimentary environment index paleoclimatic changes late Pleistocene-Holocene(41.4-4.5 ka BP) Tai Co Tibet

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Effect of sediment on concentration of dissolved phosphorus in the Three Gorges Reservoir

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International Journal of Sediment Research 2011年第1期26卷 87-95页

作者： CAO Zhijing~1,ZHANG Xinbao~2,and AI Nanshan~3 institute of Architecture and environment,Sichuan University,Chengdu 610065,China, institute of Mountain Hazards and environment,Chinese Academy of Sciences,Chengdu 610041, China, institute of Architecture and environment,Sichuan University,Chengdu 610065,China, Lecturer Institute of Architecture and Environment Sichuan University Chengdu 610065 China Prof. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Prof. Institute of Architecture and Environment Sichuan University Chengdu 610065 China

Eutrophication and algal bloom has been occurring in the Three Gorges Reservoir ever since the reservoir’s impoundment in *** concentration of dissolved phosphorus(DP) is one of the main controlling factors for algal *** sediment adsorbs DP thereby affecting the concentration of DP. The effect of the sediment reduction on the DP concentration of the Three Gorges Reservoir is discussed in this *** were taken from the Yangtze River and its tributaries,*** Minjiang River and the Tuojiang *** DP concentration of the water samples and the available phosphorus,total phosphorus,and phosphorus-fixing capacity of the sediment samples were *** amount of phosphorus adsorbed by the sediment was about 3%of the total DP load in the Yangtze *** experiment was done in the lab simulating the DP concentration,sediment concentration,and turbulence. The results showed that quite a high amount of DP was adsorbed by the *** adsorption capacity of the sediment was 135 mg/kg and the highest rate of adsorption was 29 mg/kg·*** Xiluodu Dam is located at nearly 1,100 km upstream of the Three Gorges *** Xiloudu Dam will trap sediment and thence reduce the sediment load entering the Three Gorges Reservoir after impoundment in *** is estimated that the sediment reduction due to the Xiluodu Dam may result in an increase of the DP concentration in the Three Gorges Reservoir by 6.8%.

关键词： Dissolved phosphorus Sediment load reduction Three Gorges Reservoir Adsorption capacity Eutrophication

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Characteristics of the Lower Yellow River channel shrinkage and its discriminant parameters

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Science China(Technological Sciences) 2010年第5期53卷 1374-1386页

作者： HU ChunHong1 & ZHANG GuoGang2 1 China institute of Water resources and Hydropower Research,Beijing 100038,China 2 Guangdong Electric Power Design institute,Guangzhou 510663,China China institute of Water resources and Hydropower Research Beijing China Guangdong Electric Power Design institute Guangzhou China

This paper analyzes the changing trends of the Lower Yellow River(LYR) transverse profile parameters and their aberrance points by the time series analysis *** results show that there has been a trend of changes in the LYR channel transverse profile parameters since the *** main river channel has a tendency of shrinkage year by year and the trend will be continued in the *** main features of the LYR channel shrinkage are remarkable reductions of bankfull dis-charges and bankfull areas,corresponding decreases of bankfull widths,average bankfull water depths and maximal bankfull water depths,as well as increases of bankfull water levels and width-depth ratios *** discriminant parameters for threshold of the LYR main channel shrinkage were put *** indicates that the LYR main channel began to shrink in the 1970s and has entered into a serious phase of channel shrinkage since the *** incompatible index of discharged water-sediment processes of the Sanmenxia Reservoir was introduced,which revealed that there was a trend of increasing in the incompatibility between water flow and sediment *** relations between the LYR main channel shrinkage parameters and discharged water-sediment processes of the Sanmenxia Reservoir were founded,which indicate that the LYR main channel shrinkage can be mitigated and improved through the regulation of discharged water-sediment processes of the reservoir,especially through the regulation of water-sediment incompatible *** LYR channel for water and sediment transportation can be restored and maintained.

关键词： Lower Yellow River time series analysis main river channel shrinkage discriminant parameters of channel shrinkage water-sediment incompatible index

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A COUPLED MODEL OF HYDRODYNAMICS AND WATER QUALITY FOR YUQIAO RESERVOIR IN HAIHE RIVER BASIN

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Journal of Hydrodynamics 2008年第5期20卷 574-582页

作者： LIU Xiao-bo PENG Wen-qi HE Guo-jian LIU Jing-ling WANG Yu-chun School of environment Beijing Normal University Beijing 100875 China Department of Water environment China Institute of Water Resources and Hydropower Research Beijing100038 China Department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering TsinghuaUniversity Beijing 100084 China

In order to simulate the characteristics of hydrodynamic field and mass transport processes in the Yuqiao Reservoir （YQR）, a 2-D coupled model of hydrodynamics and water quality was developed, and the water-quality related state variables in this model included CODMn, TN and TP. The hydrodynamic model was driven by employing observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The simulation of the mass transport and transformation processes of CODMn, TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcing and external loadings, with the fluxes form the bottom of reservoir and the plant photosynthesis and respiration as internal sources and sinks. A finite volume method and Alternating Direction Implicit （ADI） scheme were used to solve these equations. The model was calibrated and verified by using the data observed from YQR in two different years. The results showed that in YQR, the wind-driven current was an important style of lake current, while the concentration of water quality item was decreasing from east to west because of the external pollutant loadings. There was a good agreement between the simulated and measured values, with the minimal calculation error percent of 0.1% and 2.6% and the mean error percent of 44.0% and 51.2% for TN and TP separately. The simulation also showed that, in YQR, the convection was the main process in estuaries of inflow river, and diffusion and biochemical processes dominate in center of reservoir. So it was necessary to build a pre-pond to reduce the external loadings into the reservoir.

关键词： model simulation Yuqiao Reservoir (YQR) wind driven current water quality

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Node ordinal encoded genetic algorithm for the optimal allocation of water resources

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Progress in Natural Science:Materials International 2005年第5期15卷 448-452页

作者： YANG Xiaohua1*, YANG Zhifeng 1,2, SHEN Zhenyao1 and LI Jianqiang3(1. State Key Laboratory of Water environment Simulation, School of environment, Beijing Normal University, Beijing 100875, China 2. Key Laboratory for Water and Sediment Sciences Ministry of Education, School of environment, Beijing Normal University, Beijing 100875, China 3. Water resources and Hydropower Planning and Design General institute, MWR, Beijing 100011, China) State Key Lab. of Water Environ. Simulation Sch. of Environ. Beijing Normal Univ. Beijing 100875 China Key Lab. for Water and Sediment Sci. Min. of Edu. Sch. of Environ. Beijing Normal Univ. Beijing 100875 China Water resources and Hydropower Planning and Design General Inst. MWR Beijing 100011 China

A new method, node ordinal encoded genetic algorithm (NOEGA), is proposed for solving water resources optimal allocation problems, in which the capacity of water resources is split into a number of smaller parts so that successive operations can be overlapped. Our objective is to maximize the whole benefit function. To overcome the “dimensionality and algorithm complexity curse” while searching for solutions and looking for an optimal solution, the operations of one-point crossover operator, gene exchange operator, gene random operator, gene shift operator and node ordinal strings are established. It is proved to be an effective optimal method in searching for global solutions. The NOEGA does not need a diversity of initial population, and it does not have the problem of immature convergence. The results of two cases show that using NOEGA to solve the optimal allocation model is very efficient and robust. In addition, the algorithm complexity of NOEGA is discussed.

关键词： water resources optimal allocation node ordinal code genetic algorithm.

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