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APPLICATION OF SWAT MODEL IN THE UPSTREAM WATERSHED OF THE LUOHE RIVER

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Chinese Geographical Science 2003年第4期13卷 334-339页

作者： ZHANG Xue-song, HAO Fang-hua, CHENG Hong-guang, LI Dao-feng (State key laboratory of Water Environment Simulation,Institute of {2. Sciences, Beijing Normal university,Beijing 100875,P. R. china) State key laboratory of Water Environment Simulation Institute of Environmental Sciences Beijing Normal University Beijing 100875 P. R. China

In the Huanghe (Yellow) River basin,soil erosion is a serious problem,while runoff and sediment yield simulation has not been extensively studied on the basis of GIS (Geographic information System) and distributed hydrological model. GIS-based SWAT (Soil and Water Assessment Tool) model was used to simulate runoff and sediment in the Huanghe River basin. The objective of this paper is to examine the applicability of SWAT model in a large river basin with high sediment runoff modulus,which could reach 770t/(km2.a). A two-stage "Brute Force" optimization procedure was used to calibrate the parameters with the observed monthly flow and sediment data from 1992.to 1997,and with input parameters set during the calibration process without any change the model was validated with 1998-1999’s observed data. Coefficient of examination (R2. and Nash-Suttcliffe simulation efficiency (Ens) were used to evaluate model prediction. The evaluation coefficients for simulated flow and sediment,and observed flow and sediment were all above 0.7,which shows that SWAT model could be a useful tool for water resources and soil conservation planning in the Huanghe River basin.

关键词： luohe river watershed SWAT model sediment flow

Cadmium Release in Contaminated Soils due to Organic Acids

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Pedosphere 2004年第2期14卷 223-228页

作者： LIAOMin XIEXiao-Mei DepartmentofresourcesScience CollegeofEnvironmentalandResourceSciencesZhejiangUniversityHangzhou310029（China）.E-mail：liaomin@***

There is limited information on the release behavior of heavy metals fromnatural soils by organic acids. Thus, cadmium release, due to two organic acids (tartrate andcitrate) that are common in the rhizosphere, from soils polluted by metal smeltersor tailings andsoils artificially contaminated by adding Cd were analyzed. The presence of tartrate or citrate at alow concentration (= 2.mmol L^(-1) for citrateand >= 15 mmol L^(-1) for tartrate) apparently promoted Cd release. Under the same conditions, theCd release in naturally polluted soils was less than that of artificially ***, as the initial pH rose from 2.to 8 in the presence of citrate, a sequentialvalley and then peak appeared in the Cd release curve, while in the presence of tartrate the Cdrelease steadily decreased. In addition, Cd release was clearly enhanced as the electrolyteconcentration of KNO_3 or KC1 increased in the presence of 2.mmol L^(-1) tartrate. Moreover, ahigher desorption of Cd was shown with the KCl electrolyte compared to KNO_3 for the sameconcentration levels. This implied that the bioavailability of heavy metals could be promoted withthe addition of suitable types and concentrations of organic acids as well as reasonable fieldconditions.

关键词： artificially contaminated soil cadmium organic acid polluted soil release

environmental Geochemistry of mining Activities in Panzhihua Region, Southwestern{2.

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Journal of china university of Geosciences 2001年第4期12卷 296-300页

作者： Teng Yanguo Institute of environmental Sciences, State key {2. of Water environmental Simulation, Beijing Normal university, Beijing 100875 Tuo Xianguo Department of Nuclear resources and technology, Chengdu university of technology, Chengdu 610059 Faculty of Earth Sciences and Mineral resources China University of Geosciences Beijing 100083 Ni Shijun Zhang Chengjiang Ma YuxiaoDepartment of Nuclear Resources and Technology Chengdu University of Technology Chengdu 610059 Department of Nuclear resources and technology Chengdu University of Technology Chengdu 610059 Faculty of Earth Sciences and Mineral resources China University of Geosciences Beijing 100083 Department of Nuclear resources and technology Chengdu University of Technology Chengdu 610059

mining activities have created huge uncovered slopes, large areas of gangue ground and extensive tailings dams. This paper presents the environmental geochemistry of mining activities in Panzhihua region. The selected elements (Ti, V, Mo. Ni. Pb. Cu) show similar distribution patterns of concentration anomaly in topsoil. These concentration anomalies are located in V-Ti-magnetite slope, gangues dam and coal mine. The distinction between anthropogenic contamination and natural background is made available by the use of the enrichment factor in this study area. The anomalies of EF were smaller than that of concentration. The results from EF show that the selected elements anthropogenic pollution (EF>1) in topsoil were located in both the coal mining area and the V-Ti-magnetite mining area. In addition, the pollution sources of selected elements came from V-Ti-magnetite, slag, gangues, coal and other pollutants from mining activities.

关键词： environmental geochemistry mining activity Panzhihua region Southwestern china.

Edge Effect Correction in the S-A Method for Geochemical Anomaly Separation

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Journal of china university of Geosciences 2004年第4期15卷 379-387页

作者： Ge Yong Department of Earth and Atmospheric Science, York university, Toronto, ON, M3J 1P3, Canada State key {2. of resources and environmental information System, Institute of Geographic Sciences & Natural resources Research, Chinese Academy of Sciences, Beijing 100101, china Cheng Qiuming Department of Earth and Atmospheric Science, York university, Toronto, ON, M3J 1P3, Canada Earth Systems and Mineral Resource engineering Lab, china university of Geosciences, Wuhan 430074, china Zhang Shenyuan Department of Earth and Atmospheric Science, York university, Toronto, ON, M3J 1P3, Canada Department of Resource and Earth Science, china university of mining & technology, Beijing 100083, china Department of Earth and Atmospheric Science York University Toronto ON M3J 1P3 Canada State key laboratory of {2. and environmental information System Institute of Geographic Sciences & Natural Resources Research Chinese Academy of SciencesBeijing 100101China Department of Earth and Atmospheric Science York University Toronto ON M3J 1P3 Canada Earth Systems and Mineral Resource engineering Lab China University of Geosciences Wuhan 430074 China Department of Earth and Atmospheric Science York University Toronto ON M3J 1P3 Canada Department of Resource and Earth Science China University of Mining & Technology Beijing 100083 China

Anomaly separation using geochemical data often involves operations in the frequency domain, such as filtering and reducing noise/signal ratios. Unfortunately, the abrupt edge truncation of an image along edges and holes (with missing data) often causes frequency distribution distortion in the frequency domain. For example, bright strips are commonly seen in frequency distribution when using a Fourier transform. Such edge effect distortion may affect information extraction results; sometimes severely, depending on the edge abruptness of the image. Traditionally, edge effects are reduced by smoothing the image boundary prior to applying a Fourier transform. Zero-padding is one of the most commonly used smoothing methods. This simple method can reduce the edge effect to some degree but still distorts the image in some cases. Moreover, due to the complexity of geoscience images, which can include irregular shapes and holes with missing data, zero-padding does not always give satisfactory results. This paper proposes the use of decay functions to handle edge effects when extracting information from geoscience images. As an application, this method has been used in a newly developed multifractal method (S-A) for separating geochemical anomalies from background patterns. A geochemical dataset chosen from a mineral district in Nova Scotia, Canada was used to validate the method.

关键词： edge effect correction fractal modeling spatial information extraction zero-padding decay functions.

Study on the Waste Recycling and Reuse Patterns in Coal Mines

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Study on the Waste Recycling and Reuse Patterns in Coal Mine...

Optimal Arithmetic for Hierarchical Cluster and Pattern Recognition Applied in Coal Dust Sensor

2.10 2.d IEEE International Conference on Advanced Management Science（IEEE ICAMS 2.10）

作者： Zhenling Liu School of Management Henan university of technology Zhengzhou {2. Zhengquan Guo School of Management china university of mining & technology(Beijing) Beijing {2. Gang Li Department of resources and environmental engineering Henan Institute of engineering Zhengzhou {2. Wenbo Tan School of Management china university of mining & technology (Beijing) Beijing {2.

Since 2.06,china has become the largest coal production and consumption country in the ***,the coal mining waste has become the greatest threaten to the environment and *** to the recycling economy thought,many coal mining waste can be reused and recycled that can produce great benefits for enterprises and *** this paper,the recycling economy thought is introduced for its ***,based on the thought,the reuse and recycles of the coal mining waste practice are assigned according to the waste *** research result indicated that the recycling economy is the best chose for the economy and society sustainable development.

关键词： coal mining waste,recycling economy,industrial chains material flow

来源： cnki会议评论

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Optimal Arithmetic for Hierarchical Cluster and Pattern Reco...

FRACTAL DIMENSION ANALYSIS APPLIED TO THE 7 DRAINAGE BASINS AND THE FLOOD IN china

第二十七届中国控制会议

作者： Ma Fengying 1,2.1.College of Electronic information and Control engineering Shandong Institute of Light Industry,Jinan 2.0100,P.R.{2. 2.State key laboratory of Coal resources and Safe mining,{2. university of mining and technology,Beijing 100083,P.R.{2.

In order to resolve the conflict between coal dust sensor measurement precision and real time demands,an optimal arithmetic for dust pattern hierarchical cluster and pattern recognition was presented according to the dust sample diffraction angular *** coal dust distribution of different mines had marked difference because there was the diversity of geological structure and degree of *** hierarchical cluster method had been successfully applied in the analysis of large numbers of dust *** arithmetic first clustered the coal dust distribution type from the diffraction angular spectrum,and then the hierarchical cluster is performed to get the pattern sequence within the corresponding *** patterns could be recognized easily and rapidly with the principle of minimum variance sum between pattern and dust sample *** proves the maximal recognition speed improves *** on clustering number of transitional patterns was increased reasonably and the errors declined *** indicate the precision achieves 96%.It is concluded that the optimal arithmetic of hierarchical cluster and pattern recognition enhances the precision and real-time capability of the sensor effectively.

关键词： Coal dust Diffraction angular distribution Hierarchical cluster analysis Pattern recognition

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Natural Disaster Reduction in china 2003年第1期 33-36页

作者： Yang Xiuchun 1 and Zhu Xiaohua 2.(1. key laboratory of {2. Change and Natural Disaster, Ministry of Education of china and Institute of resources Science, Beijing Normal university, Beijing 100875 2. College of Environment, Peking university, Beijing 100871, china) ZhuangYan

According to the fractal theory, the fractal dimensions of the 7 drainage basins and the flood are preliminarily calculated on the basis of GIS in this paper. The possible relation between the fractal dimensions of the 7 drainage basins and the flood is discussed. The following conclusions are obtained: fractal dimension is an useful parameter to depict the character of flood and it is of rich information indicating the frequency and period of flood; in the studied time period, if the numbers of flood in a drainage basin are relatively great, the fractal dimension of flood in this drainage basin is comparatively great, vice versa; when the fractal dimension of a drainage basin is relatively small, the fractal dimension of flood in this drainage basin is comparatively great, vice versa.

关键词： fractal analysis fractal dimension 7 drainage basins flood china

Modeling the Roles of Precipitation Increasing in Glacier Systems Responding to Climate Warming—Taking Xinjiang Glaciated Region as Example

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Journal of Mountain Science 2005年第4期2卷 306-312页

作者： WANG Xin XIE Zichu LIU Shiyin TAO Jianjun HAN Yongshun YANG Yuelong Research Institute of Geo-spatial information Science Hunan University of Science ＆ Technology Xiangtan 411201 Hunan China key laboratory of Ice Core and Cold Region＇s Environment Cold and Arid Regions Environmental and Engineering Research Institute CAS Lanzhou 730000 China Institute of resources and Environment Hunan Normal University Changsha 410081 China Institute of Tibetan Plateau Research CAS Beijing 100029 China

The studies on prediction of climate in Xinjiang almost show that the precipitation would increase in the coming 50 years, although there were surely some uncertainties in precipitation predictions. On the basis of the structure of glacier system and nature of equilibrium line altitude at steady state （ELAo）, a functional model of the glacier system responding to climate changes was established, and it simultaneously involved the rising of summer mean temperature and increasing of mean precipitation. The results from the functional model under the climatic scenarios with temperature increasing rates of 0.01, 0.03 and 0.05 K/year indicated that the precipitation increasing would play an evident role in glacier system responding to climate change： if temperature become 1 ℃ higher, the precipitation would be increased by 10%, which can slow down the glaciers retreating rate in the area by 4 %, accelerate runoff increasing rate by 8 % and depress the ELAo rising gradient by 2. m in northern Xinjiang glacier system where semi-continental glaciers dominate, while it has corresponding values of only 1%, 5 % and 18m respectively in southern Xinjiang glacier system, where extremely continental glaciers dominate.

关键词： Glacier system climate warming precipitation increasing role

TRANSVERSE MIXING IN A TRAPEZOIDAL COMPOUND OPEN CHANNEL

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Journal of Hydrodynamics 2008年第5期20卷 645-649页

作者： ZENG Yu-hong HUAI Wen-xin GUYMER I. State key laboratory of Water {2. and Hydropower engineering Science Wuhan University Wuhan430072 China School of engineering University of Warwick Coventry CV4 7AE UK

Transverse mixing characteristics of solute in the open channel flow can provide useful information for river environmental management. The lateral mixing coefficient is a crucial parameter for reproducing the transverse mixing either by numerical simulation or by analytical prediction. Since the solute mixing can be greatly affected by the lateral variations in water depth, mixing coefficient should be determined in each sub-section （i.e., the main channel, side slope and flood plain） separately. In this article, the transverse mixing in a symmetric trapezoidal compound channel was studied based on {2. measurement of longitudinal and transverse velocity components and lateral distribution of solute concentration. The lateral mixing coefficient was estimated by adopting different Schmidt numbers in different sub-sections divided according to the developing trend of the eddy viscosity, and finally a piecewise linear profile of mixing coefficient was adopted to analytically predict the transverse solute concentration. The comparison between the analytically predicted data and the measuring solute concentration proved that this is an effective way to estimate the lateral mixing in the open channel flow with lateral variations in water depth,

关键词： transverse mixing trapezoidal compound channel mixing coefficient