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Eco-environment evolvement analysis of Ertan reservoir catchment based on remote sensing

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Science china(Technological Sciences) 2011年第S1期54卷 95-100页

作者： PANG ZhiGuo ,GE DeXiang & FU Jun E State Key Laboratory of Simulation and Regulation of water Cycle in River Basin,,china Institute of water resources and hydropower Research,Beijing 100048,china 1. State Key Laboratory of Simulation and Regulation of water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing 100048 China

hydropower project may bring with it social-economic profits as well as side *** built dam and reservoir often cause some problems to the surrounding areas,among which the ecological and environmental effects caused by hydropower projects are always concerned by the *** this article,we take the Ertan reservoir catchment as the research area and try to quantitatively analyze the variation of vegetation cover and soil erosion by remote sensing technique,and to comprehensively assess the evolvement and development trend of reservoir *** erosion,land use/cover are used as ecological and environmental indicators which reflect the changes before,after and in the period of the construction of Ertan hydropower *** by the multi-source remote sensing data(from satellite Landsat and CBERS) and DEM data,the land use/cover is interpreted through RS images which are classified both by unsupervised and supervised method,and the driving factors of the ecological changes are also *** the same time,the changes of soil loss are also monitored and analyzed during flood seasons of Ertan reservoir area before and after reservoir impoundment(1995,2.00 and 2.05) using the revised universal soil loss equation(RUSLE) .The results show that during the recent 13 years the arable land area has decreased obviously,and construction area and water surface have increased *** increase of vegetation cover has some relations with the implementation of local ecological projects,i.e.,de-farming to forestry and de-farming to pasture *** the same time,changes may also be caused by the climate adjustment in the reservoir *** the ten years from 1995 to 2.05,the high soil loss classes were transforming to lowly level classes *** of these show that the soil loss of Ertan reservoir area is getting better.

关键词： Ertan reservoir catchment eco-environment land use/cover soil loss remote sensing

Migration of Infiltrated NH_4 and NO_3 in a Soil and Groundwater System Simulated by a Soil Tank

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Pedosphere 2008年第5期18卷 628-637页

作者： WANG Chao WANG Pei-Fang State Key Laboratory of Hydrology- water resources and Hydraulic Engineering Key Laboratory of Integrated Regulationand Resource Department on Shallow Lakes Ministry of Education Environmental Science and Engineering CollegeHohai University Nanjing 210098 （China）.

The infiltration of water contaminants into soil and groundwater systems can greatly affect the quality of groundwater. A laboratory-designed large soil tank with periodic and continuous infiltration models, respectively, was used to simulate the migration of the contaminants NH4 and NO3 in a soil and groundwater system, including unsaturated and saturated zones. The unsaturated soil zone had a significant effect on removing NH4 and NO3 infiltrated from the surface water. The patterns of breakthrough curves of NH4 and NO3 in the unsaturated zone were related to the infiltration time. A short infiltration time resulted in a single sharp peak in the breakthrough curve, while a long infiltration time led to a plateau curve. When NH4 and NO3 migrated from the unsaturated zone to the saturated zone, an interracial retardation was formed, resulting in an increased contaminant concentration on the interface. Under the influence of horizontal groundwater movement, the infiltrated contaminants formed a contamination-prone area downstream. As the contaminants migrated downstream, their concentrations were significantly reduced. Under the same infiltration concentration, the concentration of NO3 was greater than that of NH4 at every corresponding cross-section in the soil and groundwater tank, suggesting that the removal efficiency of NH4 was greater than that of NO3 in the soil and groundwater system.

关键词： breakthrough curve migration NH4 NO3 soil tank experiment

A study of interaction between surface water and groundwater using environmental isotope in Huaisha River basin

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Science china Earth Sciences 2006年第12期49卷 1299-1310页

作者： SONG Xianfang1, LIU Xiangchao1, 2. XIA Jun1, YU Jingjie1 & TANG Changyuan1, 3 1. Key Laboratory of water Cycle and Related Land Surface Processes, Institute of Geographical Sciences and Natural Re- sources Research, Chinese Academy of Sciences, Beijing 100101, china 2. {2. of River and Ocean, Chongqing Jiaotong university, Chongqing 400074, china 3. Chiba university, Chiba 2.3-852., Japan 1. Key Laboratory of water Cycle and Related Land Surface Processes Institut of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 2. college of River and Ocean Chongqing Jiaotong University Chongqing 400074 China 3. Chiba university Chiba 263-8522 Japan

The surface water and groundwater are important components of water cycle, and the interaction between surface water and groundwater is the important part in water cycle research. As the effective tracers in water cycle research, environmental isotope and hydrochemistry can reveal the interrelationships between surface water and groundwater effectively. The study area is the Huaisha River basin, which is located in Huairou district, Beijing. The field surveying and sampling for spring, river and well water were finished in 2.02.and 2.03. The hydrogen and oxygen isotopes and water quality were measured at the laboratory. The spatial characteristics in isotope and evolution of water quality along river lines at the different area were analyzed. The altitude effect of oxygen isotope in springs was revealed, and then using this equation, theory foundation for deducing recharge source of spring was estimated. By applying the mass balance method, the annual mean groundwater recharge rate at the catchment was estimated. Based on the groundwater recharge analysis, combining the hydrogeological condition analysis, and comparing the rainfall-runoff coefficients from the 1960s to 1990s in the Huaisha River basin and those in the Chaobai River basin, part of the runoff in the Huaisha River basin is recharged outside of this basin, in other words, this basin is an un-enclosed basin. On the basis of synthetically analyses, combining the compositions of hydrogen and oxygen isotopes and hydrochemistry, geomorphology, geology, and watershed systems characteristics, the relative contributions between surface water and groundwater flow at the different areas at the catchments were evaluated, and the interaction between surface water and groundwater was re- vealed lastly.

关键词： environmental isotope,hydrochemistry,surface water,groundwater,interaction.

Sediment delivery ratio and its uncertainties on flood event scale:Quantification for the Lower Yellow River

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Science china(Technological Sciences) 2010年第3期53卷 854-862页

作者： FU XuDong 1,JIANG LiWei 1,WU BaoSheng 1,HU ChunHong 2.WANG GuangQian 1 &FEI XiangJun 1 1State Key Laboratory of Hydroscience and Engineering,Tsinghua university,Beijing 100084,china 2.1} Institute of hydropower and water resources Research,Beijing 100044,china 1. State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China2. China Institute of Hydropower and Water Resources Research Beijing 100044 China

Sediment delivery ratio(SDR)for fluvial rivers was formulated with sediment rating *** observed data of SDR on flood event scale of the Lower Yellow River(LYR)were adopted to examine the formulation and to calibrate the model parameters.A regression formula of SDR was then established and its 95%prediction interval was accordingly quantified to represent its overall *** types of factors including diversity of the incoming flow conditions,river self-regulation processes,and human activities were ascribed to the *** following were shown:(1)With the incoming sediment coefficient(ISC)being a variable,it was not necessary to adopt the incoming flow discharge as the second variable in the formulation of SDR;and(2.ISC=0.003 and therefore SDR=2.might be a threshold for distinguishing the characteristics of sediment transport within the *** findings would highlight sediment transport characteristics on the scale of flood event and contribute to uncertainty based analysis of water volume required for sediment transport and channel maintenance of the LYR.

关键词： sediment delivery ratio Lower Yellow River flood event uncertainty prediction interval

Study on reservoir operation optimization of Ertan hydropower Station considering GFS forecasted precipitation

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Science china(Technological Sciences) 2011年第S1期54卷 76-82页

作者： PENG Yong 1,WANG GuoLi 1,TANG GuoLei 1,ZHOU HuiCheng 1,WANG YaJun 2.& JIAN DePing 2.1 Institute of water resources and Flood Control,Dalian {2. of Technology,Dalian 11602.,china 2.Ertan hydropower Development Co.,Ltd.,Chengdu 61002.,china 1. Institute of water resources and Flood Control Dalian University of Technology Dalian 116023 China 2. Ertan hydropower Development Co. Ltd. Chengdu 610021 China

The medium-term runoff forecasting provided new information for forecast of medium and long term runoff and optimal hydroelectric power *** to the actual runoff and hydropower generating characteristics of Ertan hydropower Station,we studied the decade runoff quantitatively and grade forecast model based on Global Forecasting System(GFS) precipitation forecast information in wet season,then used the posteriori runoff transition probability and measurable probability of runoff forecast to research the uncertain runoff description based on runoff forecast;finally on the basis of the runoff description and the grading forecast accuracy of GFS-based next 10 days'total forecast precipitation,we studied the uncertain optimal operating model of Ertan hydropower Station considering runoff *** results showed that the runoff forecast considering GFS forecast precipitation and uncertainty has significantly improved the existing runoff description and operating optimization model,and obviously raised the hydropower generation efficiency of Ertan Reservoir.

关键词： global forecasting system runoff forecasting runoff description uncertainty optimal operation

Comprehensive benefit of flood resources utilization through dynamic successive fuzzy evaluation model: A case study

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中国科学：技术科学英文版 2010年第2期53卷 529-538页

作者： FENG Feng1,2. XU ShiGuo1, LIU JianWei1, LIU Dan1,3 & WU Bo4 1 Institute of water Environment, School of Civil and Hydraulic Engineering, Dalian university of Technology, Dalian 11602., {2. 2.Yellow River Conservancy Technical Institute, Kaifeng 475003, {2. 3 college of water resources, Shenyang Agricultural university, Shenyang 110161, {2. 4 Office of Flood Control and Draught Relief in Jilin Province, Changchun 130033, {2. 1. Institute of water Environment School of Civil and Hydraulic Engineering Dalian University of Technology Dalian 116024 China2. Yellow River Conservancy Technical Institute Kaifeng 475003 China3. College of Water Resources Shenyang Agricultural University Shenyang 110161 China4. Office of Flood Control and Draught Relief in Jilin Province Changchun 130033 China

Taking the flood resources utilization in Baicheng, Jilin during 2.02.2.07 as the research background, and based on the entropy weight and multi-level & multi-objective fuzzy optimization theory, this research established a multi-level & semi-constructive index system and dynamic successive evaluation model for comprehensive benefit evaluation of regional flood resources utilization. With the year 2.02.as the base year, the analyzing results showed that there existed a close positive correlation between flood utilization volume and its benefits, comprehensive evaluation value and its comparison increment. Within the six successive evaluation years, the comprehensive benefit of 2.03 was the best, in which the benefit evaluation increment reached 82.8% whereas the year of 2.04 was the worst, in which the increment was only 18.2.. Thus the sustainability and correctness of the evaluation were verified by six years successive evaluation and increment comparison. The analyzing results showed that the economic benefits, ecological benefits and social benefits of flood utilization were remarkable, and that the comprehensive benefit could be improved by increasing flood utilization capacity, which would promote the regional sustainable development as well. The established dynamic successive evaluation provides a stable theoretical basis and technical support for further flood utilization.

关键词： flood resources utilization comprehensive benefit dynamic successive fuzzy evaluation Baicheng City

QUALIFICATION OF UNCERTAINTY FOR SIMULATING SOLUTE TRANSPORT IN THE HETEROGENEOUS MEDIA WITH SPARSE GRID COLLOCATION METHOD

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Journal of Hydrodynamics 2009年第6期21卷 779-789页

作者： SHI Liang-sheng YANG Jin-zhong State Key Laboratory of water resources and {2. Engineering Science Wuhan University Wuhan 430072 China The Sonny Astani Department of Civil and Environmental Engineering University of Southern California Los Angeles CA 90089 USA

The sparse grid collocation method is discussed to qualify the uncertainty of solute transport. The Karhunen-Loeve （KL） expansion is employed to decompose the log transformed hydraulic conductivity. The head, velocity and concentration fields are represented by the Lagrange polynomial expansion. A sparse grid collocation method is then used to reduce the original stochastic partial differential equations to a set of deterministic equations which is collocated at selected interpolation （collocation） points. The collocation points are constructed by the Smolyak algorithm. The accuracy, efficiency and convergence property of sparse grid collocation method are investigated by numerical experiments. The analysis shows that stochastic collocation strategy helps to decouple stochastic computations, and all the numerical computation is possible to be implemented by existing deterministic finite element codes. The proposed method provides an efficient way to evaluate the uncertainty of the solute transport in the heterogeneous media.

关键词： stochastic partial differential equations collocation method solute transport uncertainty

RAIN INTENSITY DISTRIBUTION IN THE SPLASH REGION OF ATOMIZED FLOW

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Journal of Hydrodynamics 2006年第3期18卷 362-366页

作者： DUAN Hong-dong LIU Shi-he LUO Qiu-shi HUANG Wei School of water Resource and hydropower Wuhan University Wuhan 430072China water resources and {2. Planning and Design General Institute MWR Beijing 100011 China

Atomized flow is an unnatural two-phase flow produced while water discharges in water release structures. This flow might threaten the normal operation of hydraulic and hydroelectric installations owing to the unnatural and high-density rain as well as the unnatural and dirty mist. The splash region, the region with the highest rain intensity, hence should receive much attention during the design and operation of the hydraulic and hydroelectric installations. In this paper rain intensity distribution in the splash region of the atomized flow is investigated experimentally, and the method of random simulation is used to predict the rain intensity distribution in the splash region.

关键词： atomized flow splash rain intensity

Effect of Limestone Powder and Fly Ash on Magnesium Sulfate Resistance of Mortar

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Journal of Wuhan university of Technology(Materials Science) 2010年第4期25卷 700-703页

作者：刘数华 State Key Laboratory of water resources and {2. Engineering Science Wuhan University

The effect of limestone powder and fly ash on magnesium sulfate resistance of mortar was studied by testing on the strength, expansion and hydration products of the specimens stored in MgSO4 solution at certain periods. The experimental results show that the strength of mortar stored in MgSO4 solution increases a little before 2. d, but decreases fast subsequently. The more the contents of limestone powder and fly ash, the less the strength losses. Mortar swells in the MgSO4 solution with the soaking time. And the more the contents of limestone powder and fly ash, the less the expansion rate is. The expansion or strength loss of mortars results from the expansion of gypsum, as well as the loss of Ca（OH）2.and other hydration products of cement. The magnesium sulfate resistance of the mortars containing limestone powder and fly ash is high.

关键词： limestone powder fly ash mortar magnesium sulfate resistance