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Water demand for ecosystem protection in rivers with hyper-concentrated sediment-laden flow

Science china(Technological sciences) 2004年第z1期47卷 186-198页

作者： LUO Huaming, LI Tianhong, NI Jinren & WANG Yudong Department of Environmental Engineering, Peking University, beijing 100871, china The key {3. of Water and sediment sciences, ministry of education, beijing 100871, china Peking Univ Dept Environm Engn Beijing 100871 Peoples R China key Lab Water & sediment Sci Minist Educ Beijing 100871 Peoples R China

sediment transport is one of the main concerns in a river system with hyper-concentrated flows. Therefore, the water use for sediment transport must be considered in study on the water demand for river ecosystem. The conventional methods for calculating the Minimum Water Demand for River Ecosystem (MWDRE) are not appropriate for rivers with high sediment concentration. This paper studied the MWDRE in wet season, dry season and the whole year under different water-and-sediment conditions in the Lower Yellow River, which is regarded as a typical river with sediment-laden flows. The characteristics of MWDRE in the river are analyzed. Firstly, the water demand for sediment transport (WDST) is much larger than the demands for other riverine functions, the WDST accounts for the absolute majority of the MWDRE. Secondly, in wet season when the WDST is satisfied, not only most of the annual incoming sediment can be transported downstream, but also the water demands for other river functions can be satisfied automatically, so that the MWDRE in wet season is identical to the WDST. Thirdly, in dry season, when the WDST is satisfied, the water demands for other river functions can also be satisfied, but the low sediment transport efficiency results in significant waste of water resources. According to these characteristics and aiming at decreasing sediment deposition in the riverbed and improving the utilization efficiency of water resources, hydrological engineering works can be used to regulate or control flow and sediment so that the sediment incoming in dry season can be accumulated and be transported downstream intensively and thus efficiently in wet season.

关键词： sediment-laden flow, the Lower Yellow River, water demand for river ecosystem, water demand for sediment transport

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Paper sludge as a feasible soil amendment for the immobilization of Pb^(2+)

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Journal of Environmental sciences 2010年第3期22卷 413-420页

作者： Xiaojia He, Lei Yao, Zhu Liang, Jinren NiThe key laboratory of Water and sediment {3., ministry of education, Department of Environmental Engineering, Peking University, beijing 100871, china. The key laboratory of Water and sediment {3. Ministry of Education Department of Environmental Engineering Peking University Beijing 100871 China

The possibility of amending Pb 2＋ contaminated soil （S） with paper sludge （P） was investigated through adsorption and desorption experiments. The adsorption process of Pb 2＋ in soil containing paper sludge （SP） could be well described by pseudo second-order kinetic model and the Langmuir isotherm model. After P addition, the equilibrium time decreased greatly （from 28 to 8 hr） and the Pb 2＋ maximum adsorbed amount （Q max ） increased by a factor of more than three to 102.04 mg/g. Q max reached its maximum as S：P was 9：1 （m/m） after 10 days contact between S and P. Moreover, Pb 2＋ adsorbed amount increased with the rise of pH during the adsorption process. Desorption experiments indicated that Pb 2＋ adsorption in SP was irreversible. The metal ion fraction was analyzed with Energy Dispersive Spectrometer and Environmental Scan Electron Microscope. As a result, the addition of P to soil was found to induce a decrease in the mobile forms. The Pb 2＋ complexes formation in the presence of carbonates was the main adsorption mechanism. Overall, the paper sludge could be one of the promising soil amendments for the remediation of soil with Pb 2＋ contamination.

关键词： paper sludge pb^2+ adsorption

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Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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Science china Earth sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. key laboratory of Continental Dynamics of the ministry of education, Department of Geology, Northwestern University, Xi’an 710069,{3. 2. The Geological Lab Center,{3. University of Geosciences (beijing), beijing 100083.{3. 3. key laboratory of Orogenic Belts of the ministry of education, Department of Geology, Peking University, beijing 100871,{3. 1. key laboratory of Continental Dynamics of the ministry of education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. key laboratory of Orogenic Belts of the ministry of education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central china. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

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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 laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China key laboratory for Water and sediment {3. ministry of education School of Environment Beijing Normal University Beijing 100875 China Water Resources and Hydropower Planning and Design General Institute 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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Structures,kinematics,thermochronology and tectonic evolution of the Ramba gneiss dome in the northern Himalaya

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Progress in Natural Science:Materials International 2008年第7期18卷 851-860页

作者： Lei Guo,Jinjiang Zhang,Bo Zhang The key laboratory of Orogenic Belts and Crustal Evolution,ministry of {3.,china School of Earth and Space sciences,Peking University,beijing 100871,china The key laboratory of Orogenic Belts and Crustal Evolution Ministry of Education China School of Earth and Space sciences Peking University Beijing 100871 China

The Ramba gneiss dome,one of the north Himalayan gneiss domes,is composed of three tectono-lithologic units separated by an upper and a lower detachment ***-grade metamorphic Tethyan Himalayan sedimentary sequence formed the upper unit above the brittle upper detachment *** gneiss and a leucogranite pluton made up the lower unit beneath the ductile lower detach- ment *** middle-grade garnet-,staurolite-and andalusite-schist constituted the middle unit between the two faults,which may be that the basal part of the upper unit experienced detachment *** Ramba dome underwent three episodes of deformation in its tectonic *** first episode was a top-down-to-north-northwest sliding possibly related to the activity of the south Tibetan detachment system(STDS).The second episode was the dominant deformation related to a east–west extension,which resulted in a unique top-down-to-east kinematics and the major tectonic features of the *** third episode was a collapse sliding toward the outsides of the *** Ramba gneiss dome is possibly a result of the east–west extension and magmatic *** lower detachment fault is probably the main detachment fault separating the sedimentary sequence from the crystalline basement during the east–west extension in the dominant deformation *** diapir of the leucogranite pluton formed the doming shape of the Ramba gneiss *** pluton intruded in the core of the dome in a late stage of the dominant deformation,and its Ar–Ar cooling ages are about 6 *** indicates that the dominant deformation of the dome happened at the same time of the east–west extension represented by the north–south trending rifts throughout the northern Himalaya and southern ***,the formation of the Ramba gneiss dome should be related to this east–west extension.

关键词： Ramba gneiss dome North Himalayan gneiss domes East–west extension

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An ecological hydraulic radius approach to estimate the instream ecological water requirement

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Progress in Natural Science:Materials International 2007年第3期17卷 320-327页

作者： LIU Changming and MEN Baohui ( key laboratory of Water Cycle and Related Land Surface Process, Institute of Geographical sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101, china key laboratory of Water and sediment sciences, ministry of education & Water sciences College, beijing Normal University, beijing 100875, china Department of Hydraulic and Hydropower Engineering, North china Electric Power University, beijing 102206, china) [a]key laboratory of Water Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China [b]key laboratory of Water and sediment {3. Ministry of Education & Water Sciences Gllege Beijing Noirnal University Beijing China [c]Departhent of Hydraulic and Hydropower Engineering North China Elecfric Power University Beijing China

This essay defines the concepts of ecological flow velocity as well as ecological hydraulic radius (EHR) and proposes an ecological hydraulic radius approach (EHRA) which considers both the watercourse information (including hydraulic radius, roughness coefficient and hydraulic gradient) and the required stream velocity necessary for maintenance of certain ecological functions all together. The key parameter of EHRA is to fix the watercourse cross-sectional flow area corresponding to EHR, by which the relation between parabola shaped cross-sectional flow area and hydraulic radius is deduced. The EHRA not only meets the requirement of flow velocity for adequate fish spawning migration, but also is applicable to the ecological flows in regard with other ecological issues (such as the calculation of the instream flow requirements for transporting sediment and for pollution self-purification, etc.). This essay has illuminated the computational process taking the estimation of ecological water requirement of Zhuba Hydrologyical Station watercourse in Niqu branch of the Yalong River as an example. Additionally, we compare EHRA with Tennant approach. The result shows that the Zhuba Hydrological Station ecological water requirement calculated by EHRA lies between the minimum and favorable ecological water requirement calculated by the Tennant approach. This is due to the fact that the ecological flow velocity (such as the fish spawning migration flow velocity) was taken into consideration, producing results applicable to the practical situation.

关键词： ecological flow flow velocity cross-sectional flow area ecological hydraulic radius (HER) instreamecological water requirement.

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sediment transport capacity of hyperconcentrated flow

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 961-975页

作者： SHU AnPing1,2 & FEI XiangJun2 1 School of Environment & key laboratory of Water and sediment {3.,ministry of education,beijing Normal University,beijing 100875,china 2 State key laboratory of Hydroscience and Engineering,Tsinghua University,beijing 100084,china School of Environment & key laboratory of Water and sediment {3. Ministry of Education Beijing Normal University Beijing 100875 China State key laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

As one of the most important components of river mechanics,sediment transport capacity of sediment-laden flows has attracted much attention from many researchers working on river mechanics and hydraulic engineering. Based on the time-averaged equation for a turbulent energy equilibrium in solid and liquid two-phase flow,an expression for the efficiency coefficient of suspended load movement was derived for the two-dimensional,steady,uniform,fully-developed turbulent flow. A new structural expression of sediment transport capacity was achieved. Using 115 runs of flume experimental data,which were obtained through two kinds of sediment transport experiments in the state of equilibrium,in combination with the basic rheological and sediment transporting characteristics of hyperconcentrated flow,the main parameters in the structural expression of sediment transport capacity were calibrated,and a new formula of sediment transport capacity for hyperconcentrated flow was developed. A large amount of field data from the Yellow River,Wuding River,and Yangtze River,etc. were adopted to verify the new formula and good agreement was obtained. These results above contribute to an improved theoretical system of river mechanics and a reliable tool for management of rivers carrying high concentration of sediments.

关键词： hyperconcentrated flow turbulent energy equilibrium efficiency coefficient sediment transport capacity

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Petrology and tectonic significance of the early Mesozoic granulite xenoliths from the eastern Inner Mongolia, china

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Science china Earth sciences 2011年第10期54卷 1484-1491页

作者： SHAO JiAn 1,2 & WEI ChunJing 1 1 The key laboratory of Orogenic Belts and Crustal Evolution, ministry of education School of Earth and Space {3., Peking University, beijing 100871, china 2 key laboratory of Mineral Resources, Chinese Academy of {3., beijing 100029, china 1. The key laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space sciences Peking University Beijing 100871 China2. Key Laboratory of Mineral Resources Chinese Academy of Sciences Beijing 100029 China

Granulite xenoliths are found in the early Mesozoic diorite intrusions from Chifeng and Ningcheng areas, eastern Inner Mongolia. The granulites are granoblastic and weakly gneissic with mineral assemblage of hypersthene, diopside, plagioclase and minor biotite, amphibole and ilmenite. Some samples contain the intergrowth composed of labradorite and vermicular hypersthene, and some coarse-grained plagioclases of andesine and labradorite composition occasionally develop bytownite rims with vermicular hypersthene, indicating a possible presence of garnet. Presence of blastogabbroic texture and hypersthene with diopside exsolution lamellae in some samples suggests that the protolith of the granulite is norite or gabbro. On the basis of metamorphic research and thermobaric calculation, the evolution of the granulite xenoliths is summarized into the following stages: (1) Isobaric cooling of underplated noritic or gabbroic magma in the lower crust led to the formation of probable garnet-bearing medium-high pressure granulite. (2) These higher pressure granulites were adiabatically uplifted to upper crust by dioritic magma and transformed to low pressure two-pyroxene granulite during an isothermal decompression. (3. The two-pyroxene granulite underwent retrograde metamorphism of different degrees during an isobaric cooling process as a result of crystallization and cooling of the dioritic magma. The pyroxenite-dominated cumulates and the medium-high pressure granulites may have rejuvenated the lower crust during the early Mesozoic.

关键词： early Mesozoic granulite xenolith lower crust North china Craton

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DISCRIMINANT ANALYSIS BASED ON STATISTICAL DEPTH

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Journal of Systems Science & Complexity 2010年第2期23卷 362-371页

作者： Jiao JIN·Hengjian CUI School of Mathematical sciences,key laboratory of Mathematics and Complex Systems,{3. of education, beijing Normal University,beijing 100875,china. School of Mathematical sciences Key Laboratory of Mathematics and Complex Systems Ministry of Education

In the past two decades,many statistical depth functions seemed as powerful exploratoryand inferential tools for multivariate data analysis have been *** this paper,a new depthfunction family that meets four properties mentioned in Zuo and Serfling(2000)is *** aclassification rule based on the depth function family is *** classification parameter b couldbe modified according to the type-Ⅰ error α,and the estimator of b has the consistency and achievesthe convergence rate n^(-1/2).With the help of the proper selection for depth family parameter c,theapproach for discriminant analysis could minimize the type-Ⅱ error β.A simulation study and a realdata example compare the performance of the different discriminant methods.

关键词： Depth discriminant analysis location parameter MVE scatter matrix.

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Efficiency of sediment transport by flood and its control in the Lower Yellow River

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Science china(Technological sciences) 2004年第z1期47卷 173-185页

作者： NI Jinren1, LIU Xiaoyong2, LI Tianhong1, ZHAO Ye’an3.& JIN Ling1 1. Department of Environmental Engineering, Peking University The key laboratory of Water and Sedi- ment sciences,{3., beijing 100871, china 2. General Institute of Water Resources and Hydropower Planning and Design, ministry of Water Re- sources, beijing 100011, china 3. The Yellow River Conservancy Commission, Zhengzhou 450003. china 1. Department of Environmental Engineering Peking University 100871 Beijing China 2. The key laboratory of Water and sediment {3. Ministry of Education 100871 Beijing China 3. General Institute of Water Resources and Hydropower Planning and Design Ministry of Water Resources 100011 Beijing China 4. The Yellow River Conservancy Commission 450003 Zhengzhou China

This paper presents the characteristics of sediment transport by flood in the Lower Yellow River with the reach from Huayuankou to Gaocun, which is regarded as a typical braided pattern. The Artificial Neural Network Model on Water Use for sediment Transport (WUST) by flood was established based on the measured data from 1980 to 1998. Consequently, simulations of controlling process of sediment transport by flood were made in terms of the control theory under different scenarios. According to the situation of sediment transport by flood in the Lower Yellow River, Open-Loop control system and feedback control system were adopted in system design. In the Open-Loop control system, numerical simulations were made to reveal the relationship between average discharge of flood and the WUST with varying sediment concentrations. The results demonstrate that sediment concentration has significant influence on the controlling process of flood flow to WUST. It is practical and efficient to control WUST if sediment concentration is less than 20 kg/m3. In the feedback control system, controlling processes of sediment concentration and flood discharge for sediment transport were simulated respectively under given conditions, and it was found that sediment transport process could be controlled completely by sediment concentration and discharge at the inlet of the reach from Huayuankou to Gaocun. Using the same method, controlling processes of sediment transport by flood in other reaches in the Lower Yellow River were also simulated. For the case of sediment concentration being 20 kg/m3. the optimized controlling discharge ranges from 23.0 to 2900 m3.s in the lower reach of Huayuankou. This study is also of significance to flood control and flushing sediment in the Lower Yellow River with proper operation modes of Xiaolangdi Reservoir.

关键词： the Lower Yellow River, flood, sediment transport, efficiency, simulation, control.

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