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Effects of fluvial processes and human activities on stream macro-invertebrates

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International Journal of Sediment Research 2011年第4期26卷 416-430页

作者： Xue-hua DUAN,Zhao-Yin WANG,and Meng-zhen XU 1 Ph.D.,state key laboratory of Hydroscience and Engineering,Tsinghua {3.,Beijing 100084,china Jiangyin Water Conservancy and Farm Machinery Bureau,Jiangyin 21443. china, 2 Prof,state key laboratory of Hydroscience and Engineering,Tsinghua {3.,Beijing 100084,china, 3.Doctoral candidate,state key laboratory of Hydroscience and Engineering,Tsinghua {3.,Beijing 100084,china, Ph.D. State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Jiangyin Water Conservancy and Farm Machinery Bureau Jiangyin 214431 China Tel: 86-*** (M) Prof. State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Doctoral candidate State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

Benthic macro-invertebrates are vital components of river *** effects of fluvial processes and human activities on the distribution of macro-invertebrates were studied through field investigations and ***-one sampling sites on 3. rivers in china were selected to investigate the structures of macro-invertebrate *** rivers,according to their fluvial conditions,are classified as streams with a stable channel bed,degrading channel bed,aggrading channel bed,and intensive bed load *** structures of macro-invertebrate fauna for the four types of rivers are very *** rivers have a large number of individuals,abundant fauna, and high biodiversity;while the density and taxa richness for degrading rivers are small,and those for aggrading rivers are much less;whereas the ecology of rivers with intensive bed load motion are the *** paper proposes that streambed stability is the primary influential factor shaping the structure of benthic macro-invertebrate *** pollution can obviously result in the decrease of biodiversity,in the simplification of macro-invertebrate structures,and in the distortion of functional feeding group *** a river with high total nitrogen content,the relative abundance of collector-gatherers is high,and that of collector-filterers,scrapers,shredders,and predators are ***,shredders,and predators disappear in severely polluted *** isolation of aquatic habitat results in a distinct decrease of individual numbers and taxa *** result demonstrates that the connectivity of aquatic habitat significantly affects macro-invertebrate assemblages.A practical method to calculate a Habitat Suitability Index(HSI) is proposed,integrating the effects of the primary physical(including biotic and abiotic) and chemical *** biodiversity and taxa richness increase non-linearly with HSI.

关键词： Macro-invertebrate Streambed stability Substratum Isolation Habitat suitability Water pollution

Tectono-chronologic constraints on a Mesozoic slip and thrust belt in the eastern Jiaodong Peninsula

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Science china Earth Sciences 2007年第1期50卷 25-32页

作者： ZHANG HongYuan1,2, HOU QuanLin3.& CAO DaiYong 4 1 Institute of Geology, Chinese Academy of geological Sciences, Beijing 10003., china 2 state {3. laboratory of geological processes and mineral resources, china university of geosciences, Beijing 100083. china 3.Graduate School of china Acacemy of Sciences, Beijing 10003., china 4 {3. laboratory of Coal resources (CUMT), Ministry of Education, Beijing 100083. china Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China state key laboratory of {3. processes and mineral resources China University of Geosciences Beijing 100083 China Graduate School of china Acacemy of Sciences Beijing 100039 China key laboratory of Coal resources (CUMT) Ministry of Education Beijing 100083 China

A major slip and thrust belt within the eastern Jiaodong Peninsula is located at the eastern terminal of the Qinling-Dabie-Sulu orogenic belt between the Sino-Korea Block and Yangtze Block. Although a lot of isotope chronologic data have been obtained regionally, little structural chronological research has been conducted in this region and this paper corrects that. Syn-deformational minerals were system-atically selected from samples of the NE-ENE trending transpressional shear zones and transpres-sional nappes and carefully analysed using 40Ar/3.Ar methods. Two tectonic events were defined with the first event resulting from early movement of transpressional nappes around 190 Ma ago. This ac-cords with the period of syn-orogenic sinistral slip of the Tan-Lu faults and clockwise shear in the Eastern Qinling-Tongbaishan part of the Qinling-Dabie-Sulu orogenic belt. The second event involved strikeslip thrust movement of deep shear zones between 13.Ma and 120Ma. This resulted from the onset of Mesozoic tectonic conversion in the eastern Jiaodong Peninsula. The sinistral strikeslip-thrusting in Jiaodong Peninsula and the extensional tectonism (toward ESE) in Liaodong Peninsula probably resulted in the clockwise rotation of Korea Peninsula in late Mesozoic.

关键词： the eastern Jiaodong Peninsula tectono-chronology 40Ar/3.Ar strikeslip and thrust belt.

Effect of incoming sediment on the transport rate of bed load in mountain streams

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International Journal of Sediment Research 2009年第3期24卷 260-273页

作者： Guo-An YU1, Zhao-Yin WANG2, Kang ZHANG3. Tung-Chiung CHANG4, and Huaixiang LIU51 Dr., Institute of Geographical Sciences and Natural resources Research, Chinese Academy of Sciences, Beijing 100101, china and Dept. of Hydraulic Engineering, Tsinghua university, 2 Prof., {3. key laboratory of Hydroscience and Engineering, Tsinghua university, Beijing 100101, china, 3.Ph.D. candidate, {3. key laboratory of Hydroscience and Engineering, Tsinghua university, Beijing 100084, china 4 Ph.D. candidate, Tsinghua university, Beijing 100084, china and Prof., Kaoyuan university, Kaohsiung 82151, Taiwan, china 5 Dr., {3. key laboratory of Hydroscience and Engineering, Tsinghua university, Beijing 100084, china Dr. Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China and Dept. of Hydraulic Engineering Tsinghua University Prof. State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100101 China Ph.D. candidate State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Ph.D. candidate Tsinghua University Beijing 100084 China and Prof. Kaoyuan University Kaohsiung 82151 Taiwan China Dr. State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

Field experiments were conducted on bed load transport in the Diaoga River, a mountain stream in southwest china, to study the variation of bed load transport with varying sediment supply. The rate of bed load transport is greatly affected by incoming sediment (load and size). Under the same flow conditions, bed load transport rates may differ by three orders of magnitude depending on whether measurements were taken before or after the first flood of the year. The relation of the "bed load transport rate versus flow intensity" appears to have similar characteristics as a clockwise looped-rating curve. Experiments also were conducted during the non-flood season to study bed load transport processes with different incoming load from an upstream section. Bed load with different sizes can be grouped into two types: traveling bed load and structural bed load. Traveling bed load is composed of sediment finer than a critical size, Dc, and its transport rate depends mainly on the incoming sediment rate. The incoming sediment rate can alter the rate of bed load transport by three orders of magnitude. Structural bed load is composed of coarser sediment and its transport rate closely relies on the flow intensity.

关键词： Mountain streams Bed load transport Sediment supply Sediment size distribution

Use of Spectrographic Analyses to Characterize the Unique Features of Sodic-Lithian and Cesium-Rich Platy Beryl

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地学前缘 2009年第S1期16卷 168-168页

作者： Yan Liu,Jun Deng,Liqiang Yang,Qingfei Wang state key laboratory of {3. processes and mineral resources,china university of geosciences,Beijing 100083.china.

Since most beryls are characterized by prismatic configuration and originate from pegmatite and granite,platy beryl is considered especially rare. Therefore,the aims of this study are to determine the spectrographic and chemical characteristics of the platy beryl;examine the relationships between the spectrographic parameters and alkali elements and discuss the possible genesis of its platy habit based

关键词： beryl trace elements ICP vibrational spectroscopy XRD Xuebaoding Mountain

Electrochemical properties of Bismuth Doped α-MnO2 Nanorods for Supercapacitor Studies

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Electrochemical properties of Bismuth Doped α-MnO2 Nanorods...

Thermal stabilization of ordered mesoporous alumina with modification of rare earth

中国颗粒学会超微颗粒专委会2011年年会暨第七届海峡两岸超微颗粒学术研讨会

作者： Yinping Xu~a,Chao Yang~(a,b,*),Lili Gao~a,Xike Tian~(a,b,*) Suxin Zhang~c,Yanxin Wang~b a Faculty of Material Science and Chemistry Engineering,china university of geosciences,{3.,P R china b School of Environmental Studies,china university of geosciences,wuhan 430074,P R china c state key {13. of geological processes and mineral resources,china university of geosciences,wuhan,430074,P.R.china

Bismuth doped α-MnO nanorods are synthesized by a simple hydrothermal method based on the redox *** samples are characterized by X-ray diffraction(XRD),Field emission scanning electron microscopy(FE-SEM) and transmission electron microscopy(TEM).Electrochemical properties of the products are evaluated by cyclic voltammetry and galvanostatic charge-discharge *** ours work,the pure MnO nanorods exhibits a relatively low specific capacitance of 87 Fg,whereas the 1%(atomic ratio) Bi-doped MnO exhibits excellent pseudocapacitive behavior with a specific capacitance of 171 Fg and shows a better cycle *** addition,highly stable and reversible performance after 2000 charge-discharge cycles is also demonstrated.

关键词： Manganese dioxide Bismuth Doped Supercapacitor Electrochemical properties hydrothermal

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Thermal stabilization of ordered mesoporous alumina with mod...

Stability analysis on Tingzikou gravity dam along deep-seated weak planes during earthquake

中国颗粒学会超微颗粒专委会2011年年会暨第七届海峡两岸超微颗粒学术研讨会

作者： Lili Gao~a,Chao Yang~(a,b*),Yinping Xu~a,Xike Tian~(a,b*) Suxin Zhang~c,Yanxin Wang~b a Faculty of Material Science and Chemistry Engineering,china university of geosciences,{3.,PR china b School of Environmental Studies,china university of geosciences,wuhan 430074,P R china c state key {13. of geological processes and mineral resources,china university of geosciences,wuhan,430074,P.R.china

The synthesis of organized mesoporous alumina has exploring new territory for application of this type of materials,particularly as catalysts or catalyst *** specific surface area and thermal stability are the major requirements for alumina as catalyst *** this paper,we report a facile synthesis of ordered and high thermal stability mesoporous alumina doping with La or Ce ions under hydrochloric acid *** stability improvements by rare earth(La and Ce) doping are *** our work,we find that both rare earth doping can effectively stabilize the amorphous walls of alumina *** material presents the ability to maintain the surface area and pore structure upon prolonged heating below 700℃. Further more,as the results shows the modification of La for improving the thermal stability is more effective than ***,Cl does not strongly influence the self-assembly process in the closed system.

关键词： Mesoporous materials Surfaces area rare earth

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Frontiers of Structural and Civil Engineering 2012年第1期6卷 69-75页

作者： Weiping HE Yunlong HE state key laboratory of Water {3. and Hydropower Engineering Science Wuhan UniversityWuhan 430072China

The stability of a gravity dam against sliding along deep-seated weak planes is a universal and important problem encountered in the construction of *** is no recommended method for stability analysis of the dam on deep-seated weak planes under earthquake condition in Chinese design *** Tingzikou dam as an example,the research in this paper is focused on searching a proper way to evaluate the seismic safety of the dam against sliding along deep-seated weak planes and the probable failure modes of dam on deep-seated weak planes during *** is concluded that there are two probable failure modes of the dam along the main weak geological planes in the *** the first mode,the concrete tooth under the dam will be cut and then the dam together with part foundation will slide along the muddy layer;in the second mode,the dam together with part foundation will glide along the path consist of the weak rock layer under the tooth and the muddy layer downstream the *** there is no geological structure planes to form the second slip surface,the intersection of the main and the second slip surface is 40 to 80 m downstream from dam toe,and the angle between the second slip surface and the horizontal plane probably be 25 to 45 degrees.

关键词： gravity dam deep-seated weak planes stability against sliding earthquake

Tectonic evolution of the Qinling-Tongbai orogenic belt

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Tectonic evolution of the Qinling-Tongbai orogenic belt

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

中国矿物岩石地球化学学会第13.学术年会

作者： WU Yuan-bao~1,ZHENG Yong-fei~2 1.state key laboratory of {3. processes and mineral resources,Faculty of Earth Sciences,china university of geosciences, wuhan 430074,china 2.CAS key laboratory of Crust-Mantle Materials and Environments,School of Earth and Space Sciences,university of Science and Technology of china,Hefei 23.026,china

＜正＞The Qinling-Tongbai-Dabie-Sulu orogenic belt marks the suture between the North and South china Blocks in Central china,forming one of the most important orogens in the eastern *** are hot controversies about the location and number of sutures and the timing of arc-continent and continent-continent collisions during the convergence between the North and South china *** Dabie-Sulu orogenic belt is characterized by the occurrence of Triassic UHP eclogite-facies metamorphic rocks due to the Triassic continental deep subduction. Thus,the Triassic continent-continent collision is evident in east-central *** the other hand,there are Paleozoic events of arc-continent collision in the Qinling-Tongbai orogenic belt that were overprinted by the Triassic process of continental *** has caused much complexity on the time and location of arc-continent and continent-continent collisions between the North and South china *** present an

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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 {3.,Beijing 100084,china 2 Yellow River Engineering Consulting Co.,Ltd.,Zhengzhou 450003.china 3.North china Institute of Water Conservancy and Hydropower,Zhengzhou 450008,china 4 china Institute of Water resources and Hydropower Research,Beijing 10003.,china state key laboratory of Hydroscience and Engineering Tsinghua University china Institute of Water resources and Hydropower Research

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