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Influence of Vegetation on Runoff and Sediment in Wind-water Erosion Crisscross Region in the Upper Yellow River of China

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Chinese Geographical Science 2017年第4期27卷 569-576页

作者： WANG Jinhua li Zhanbin YAO Wenyi DONG Guotao Xi'an University of Technology Xi'an 710048China Key Laboratory of Soil and Water Loss Process and Control on the Loess Plateau of Ministry of Water Resources Yellow River Institute of Hydraulic ResearcesZhengzhou 450003China

All characteristics of vegetation,runoff and sediment from 1960 to 2010 in the Xiliu Gully Watershed,which is a representative watershed in wind-water erosion crisscross region in the upper reaches of the Yellow River of China,have been analyzed in this *** on the remote sensing image data,and used multi-spectral interpretation method,the characteristics of vegetation variation in the Xiliu Gully Watershed have been *** the rules of precipitation,runoff and sediment's changes have been illuminated by using mathematical statistics ***′s more,the influence mechanism of vegetation on runoff and sediment has been discussed by using the data obtained from artificial rainfall simulation *** results showed that the main vegetation type was given priority to low coverage,and the area of the low vegetation coverage type was reducing year by *** the country,the area of the high vegetation coverage type was gradually *** a word,vegetation conditions had got better improved since 2000 when the watershed management project *** average annual precipitation of the river basin also got slightly increase in 2000–*** average annual runoff reduced by 37.5%,and the average annual sediment reduced by 73.9% in the same *** results of artificial rainfall simulation tests showed that the improvement of vegetation coverage could increase not only soil infiltration but also vegetation evapotranspiration,and then made the rainfall-induced runoff production *** root system could increases the resistance ability of soil to erosion,and vegetation aboveground part could reduce raindrop kinetic energy and splash soil ***,with the increase of vegetation coverage,the rainfall-induced sediment could decrease.

关键词： vegetation coverage runoff sediment infiltration rate wind-water erosion crisscross region

ON　SOME　ABNORMAL　PHENOMENA　DURING　HYPERCONCENTRATED　FLOODS　IN　THE　LOWER　YELLOW　RIVER

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International Journal of Sediment research 1994年第2期 30-38页

作者： li Yong and ZHANG Xiaohua(li Youg. ZHANG Xiaohua, , institute of hydraulic research,Yellow River Conservancy Commission)

ＯＮＳＯＭＥＡＢＮＯＲＭＡＬＰＨＥＮＯＭＥＮＡＤＵＲＩＮＧＨＹＰＥＲＣＯＮＣＥＮＴＲＡＴＥＤＦＬＯＯＤＳＩＮＴＨＥＬＯＷＥＲＹＥＬＬＯＷＲＩＶＥＲＬＩＹｏｎｇａｎｄＺＨＡＮＧＸｉａｏｈｕａ（Ｔｈｉｓｒｅｓｅａｒｃｈｐ...

ＯＮＳＯＭＥＡＢＮＯＲＭＡＬＰＨＥＮＯＭＥＮＡＤＵＲＩＮＧＨＹＰＥＲＣＯＮＣＥＮＴＲＡＴＥＤＦＬＯＯＤＳＩＮＴＨＥＬＯＷＥＲＹＥＬＬＯＷＲＩＶＥＲＬＩＹｏｎｇａｎｄＺＨＡＮＧＸｉａｏｈｕａ（Ｔｈｉｓｒｅｓｅａｒｃｈｐｒｏｊｅｃｔｗａｓｓｕｐｐｏｒｔｅ...

关键词：

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燕山水库信息管理自动化系统集成技术

水电能源科学 2009年第6期27卷 188-189,65页

作者：马福恒李永江刘成栋南京水利科学研究院江苏南京210029 河南省燕山水库建设管理局河南叶县467224

针对水库建立综合自动化系统可实现水库现代化科学运行管理,采用现代计算机、网络等技术手段对燕山水库水雨情、大坝安全监控、闸门监控、视频监视、水电站自动化、办公自动化等各子系统进行有机集成,实现了资源共享、科学调度、合理高... 详细信息

针对水库建立综合自动化系统可实现水库现代化科学运行管理,采用现代计算机、网络等技术手段对燕山水库水雨情、大坝安全监控、闸门监控、视频监视、水电站自动化、办公自动化等各子系统进行有机集成,实现了资源共享、科学调度、合理高效利用水资源及水库安全科学管理的目标。

关键词：综合自动化系统 Web技术集成方案系统功能

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地下水不稳定流动问题

水利水运科学研究 1985年第3期 51-65页

作者：沙金煊李定方水工研究所

本文探讨了地下水向运动边界的不对称流动问题。这类问题包括河间地块地下水向河流的补给,及农田地下水向两侧排水沟管的流动等。本文在考虑这种流动图案时,还计及了铅直方向的补给,诸如潜水蒸发、降雨入渗及承压水越流补给。这些补给... 详细信息

本文探讨了地下水向运动边界的不对称流动问题。这类问题包括河间地块地下水向河流的补给,及农田地下水向两侧排水沟管的流动等。本文在考虑这种流动图案时,还计及了铅直方向的补给,诸如潜水蒸发、降雨入渗及承压水越流补给。这些补给量是随着时间而变化的,此外对边界水位的处理也是随时间变化的,在任一时刻,地下水运动的各水力要素均在不停地变化,因而这个问题十分复杂,目前未见有介绍。本文分别采用解析法、有限元法和边界元法求解,并用实例作了计算对比,各法所得结果互为一致。

关键词：不稳定流动不对称边界元法有限元法流体流动边界元素法数值分析自流水承压水地下水边界分水线分水岭水文地质参数地下水位

Development and Application of An Urban Water Resources Management Information System

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Development and Application of An Urban Water Resources Mana...

THE DYNAMIC CALCULATION HETHOD OF THE UNDERGROUND COMPOSITE CYliNDRICAL STRUCTURES WITH SOFT BACKPACKING IN THE PLANE STRESS WAVE ENVIRONMEHT

第三届世界水论坛

作者： li Yun FAN Ziwu XU Shikai & WAN Shenggannanjing hydraulic research institute

＜正＞In this paper, an urban water resources management information system （WRMIS） is developed with the integration of database, GIS and water resources management models. The system is of the following functions: basic information inquiry, surface water and groundwater kinematic simulation, statistics of water consumption, forecast of water demand, control of pollutant diffusion, monitoring of water quality and evaluation of water environment, etc. It can provide technical supports for scientific management and reasonable allocation of urban water resources.

关键词： management information system (MIS) water resources management GIS

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THE DYNAMIC CALCULATION HETHOD OF THE UNDERGROUND COMPOSITE ...

research on casing deformation prevention technology based on cementing slurry system optimization

International Workshop on Blast-Resistant Structures

作者： li Huan-qiu Zhao Yu-xiang Luoyang hydraulic Technology research institute

＜正＞In this paper, the dynamic calculation method for the underground composite cylindrical structure with the soft backpacking in the plane stress wave environment has been presented on the basis of the results of tests and FEH calculation. The method takes the surrounding rock with a certain thickness and the lining as the outside and inside structure of the system, respectively. Between them, there is a soft backpacking material layer which is consisdered as elasto-plastic continuous body. The functional of the system is established on the basis of energy method. The non-linear motion equations of the system are derived from Hamilton’s variational principle, and are resolved. Finaly, the calculations for this system are made by using the method.

关键词： (1) underground composite structure (2) plane stress wave (3) elastoplastic (4)calculation method

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Petroleum Science 2024年第2期21卷 1231-1240页

作者： Yan Yan Meng Cai Wen-Hai Ma Xiao-Chuan Zhang li-Hong Han Yong-Hong liu State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research InstituteXi©an710077ShaanxiChina College of Mechanical and Electrical engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province Chengdu610095SichuanChina CNPC Daqing Oilfield Company Daqing163453HeilongjiangChina

The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cement sheath was firstly analyzed by discrete element method, and the effect of hollow particles in cement on casing deformation was investigated by laboratory experiment method. Finally, field test was carried out to verify the improvement effect of the casing deformation based on cement slurry modification. The results show that the formation displacement can be absorbed effectively by hollow particles inside the cement transferring the excessive deformation away from casing. The particles in the uncemented state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cement reaches 1:4. According to the field test feedback, the method based on optimization of cement slurry can effectively reduce the risk of casing deformation, and the recommended range of hollow microbeads content in the cement slurry is between 15% and 25%.

关键词： Cement slurry Hollow ceramsite Casing deformation Formation slip Field test

Long-Term Extreme Wave Characteristics in the Water Adjacent to China Based on ERA5 Reanalysis Data

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Journal of Ocean University of China 2024年第1期23卷 1-10页

作者： DU Wenyan ZHANG Xuri SHI Hongyuan li Guanyu ZHOU Zhengqiao YOU Zaijin ZHANG Kuncheng School of hydraulic engineering Ludong UniversityYantai 264025China Center for Ports and Maritime Safety(CPMS) Dalian Maritime UniversityDalian 1160263China Nation Ocean Technology Center Tianjin 300111China Navigation Guarantee Center of South China Sea(NGCS)MOT Guangzhou Hydrographic Center Guangzhou 510320China institute of Marine Development/Military Teaching Department School of MarxismOcean University of ChinaQingdao 266100China Yantai Kekan Marine Technology Co. Ltd.Yantai 264025China

Extreme waves have a profound impact on coastal infrastructure;thus,understanding the variation law of risky analysis and disaster prevention in coastal zones is *** paper analyzed the spatiotemporal characteristics of extreme wave heights adjacent to China from 1979 to 2018 based on the ERA5 *** extreme value analysis is undertaken in eight repre-sentative points to investigate the trends in the values of 50-and 100-year wave *** show that the mean value of extreme waves is the largest in the eastern part of Taiwan Island and the smallest in the Bohai Sea from 1979 to *** the extreme wave height in the northeastern part of Taiwan Island shows a significant increase trend in the study *** analysis shows remarkable variations in the values of 50-and 100-year significant wave heights in eight *** the annual mean change,E1,E2,S1,and S2 present an increasing trend,while S3 shows a decreasing *** points for the seasonal mean change demon-strate an increasing trend in spring and winter,while other points show a decreasing trend in summer and ***,the E1 point growth rate is large in autumn,which is related to the change in typhoon intensity and the northward movement of the typhoon path.

关键词： extreme wave height NEVA wave climate ERA5 reanalysis

Spatiotemporal characteristics and driving mechanisms of land use/land cover(LULC)changes in the Jinghe River Basin,China

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Journal of Arid Land 2024年第1期16卷 91-109页

作者： WANG Yinping JIANG Rengui YANG Mingxiang XIE Jiancang ZHAO Yong li Fawen LU Xixi State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China Xi'an University of TechnologyXi'an 710048China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China State Key Laboratory of hydraulic engineering Simulation and Safety Tianjin UniversityTianjin 300072China Department of Geography National University of SingaporeSingapore 117570Singapore

Understanding the trajectories and driving mechanisms behind land use/land cover(LULC)changes is essential for effective watershed planning and *** study quantified the net change,exchange,total change,and transfer rate of LULC in the Jinghe River Basin(JRB),China using LULC data from 2000 to *** trajectory analysis,knowledge maps,chord diagrams,and standard deviation ellipse method,we examined the spatiotemporal characteristics of LULC *** further established an index system encompassing natural factors(digital elevation model(DEM),slope,aspect,and curvature),socio-economic factors(gross domestic product(GDP)and population),and accessibility factors(distance from railways,distance from highways,distance from water,and distance from residents)to investigate the driving mechanisms of LULC changes using factor detector and interaction detector in the geographical detector(Geodetector).The key findings indicate that from 2000 to 2020,the JRB experienced significant LULC changes,particularly for farmland,forest,and *** the study period,LULC change trajectories were categorized into stable,early-stage,late-stage,repeated,and continuous change *** the stable change type,the late-stage change type predominated the LULC change trajectories,comprising 83.31% of the total change *** period 2010-2020 witnessed more active LULC changes compared to the period *** LULC changes exhibited a discrete spatial expansion trend during 2000-2020,predominantly extending from southeast to northwest of the *** driving factors on LULC changes included slope,GDP,and distance from *** interaction detection results imply either bilinear or nonlinear enhancement for any two driving factors impacting the LULC changes from 2000 to *** comprehensive understanding of the spatiotemporal characteristics and driving mechanisms of LULC changes offers valuable insights for the planning and sustainable management

关键词： land use/land cover(LULC)changes driving mechanisms trajectory analysis geographical detector(Geodetector) Grain for Green Project Jinghe River Basin