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

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, Ministry of Education, beijing 100871, China 2. {2. 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 Sciences Ministry of Education 100871 Beijing China 3. general institute of Water {2. 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 2. 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 2. kg/m3, the optimized controlling discharge ranges from 2.90 to 2.00 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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RECENT EXPERIENCES OF CFRD IN CHINA

RECENT EXPERIENCES OF CFRD IN CHINA

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International Conference of hydropower

作者： JIANG Guocheng China institute of Water resources and {2. Research beijing zhao zengkai general planning and design institute of Water resources and {2. beijing

＜正＞China started CFRD construction with modern technologies since the middle of the 1980s. Till the end of 2.03, there are more than 110 CFRDs constructed or under construction. Among them, 31 CFRDs have a height o... 详细信息

关键词： concrete face rockflll dams face slab rockflll dam

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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 2.00 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 2.00 to 2.2.,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 2.10-2.2. witnessed more active LULC changes compared to the period *** LULC changes exhibited a discrete spatial expansion trend during 2.00-2.2.,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 2.00 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

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Surface water resource attenuation attribution and patterns in Hai River Basin

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Science China Earth Sciences 2024年第5期67卷 1545-1560页

作者： Qingming WANG Yong zhao Hao WANG Jiaqi ZHAI Yue ZHANG Fan HE Rong LIU Mengyang MA State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research(IWHR)Beijing 100038China Key Laboratory of Water Safety for beijing-Tianjin-Hebei Region of Ministry of Water resources Beijing 100038China general institute of Water {2. and hydropower planning and design Ministry of Water ResourcesBeijing 100120China

From 1956 to 2.16,Hai River Basin suffered the most severe surface water resource attenuation among the 10 first-class river basins in *** on the surface water circulation process,and evolving characteristics of precipitation and underlying surface in Hai River Basin,this study attributed the causes of surface water resource attenuation to six primary impact factors,analyzed each factor's quantitative contribution,and revealed four patterns of surface water resource attenuation in Hai River *** pattern of the dominant factor:comparing the 1980–2.00 period with the 1956–1979period,the variation of precipitation is the dominant factor of which contribution is 7 billion m^(3),accounting for 59%of total11.7 billion m^(3);comparing the 2.01–2.16 period with the 1956–1979 period,the increasing of vegetation cover in mountainous area is the dominant factor of which contribution is 2.78 billion m3,accounting for 51%of total 4.9 billion m^(3).The pattern of spatial distributions:comparing the 2.01–2.16 period with the 1956–1979 period,mountainous areas were more affected by increasing vegetation cover which for example contributed 42.in Luan River Basin mountainous;the plains were more impacted by farmland ridge interception which for example contributed 51%in Beisi River Basin *** pattern of attenuation trend:comparing the 2.01–2.16 period with the 1980–2.00 period,surface water resources in mountainous areas continued to decline,owing to the increasing water consumption of large-scale vegetation restoration,while the influence of the underlying surface changes on surface water resources in plains areas tended to remain *** pattern of reversible change:among factors led to surface water resource attenuation,the human activity,including vegetation cover increase,farmland ridge interception,and urbanization expansion,contributed 36%of the attenuation,which resulted in the variation of precipitation-runoff *** study improved the traditiona

关键词： Hai River Basin Surface water resources Contribution decomposition Quantitative contribution Attenuation patterns

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基于激光扫描技术的复杂工程挖填方计算

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水电能源科学 2011年第12期29卷 95-97,131页

作者：刘昌军叶长锋赵雨解家毕中国水利水电科学研究院北京100038 国核电力规划设计研究院北京100094

以唐海幸福花园小区复杂基坑为例,介绍了利用激光扫描仪进行复杂挖填方量计算的流程与方法,提出了基于激光点云数据的非地面点的自动滤波算法、基于移动最小二乘法拟合地表的DEM数据和任意边界的挖填方计算方法等;并利用IDL语言编制了... 详细信息

以唐海幸福花园小区复杂基坑为例,介绍了利用激光扫描仪进行复杂挖填方量计算的流程与方法,提出了基于激光点云数据的非地面点的自动滤波算法、基于移动最小二乘法拟合地表的DEM数据和任意边界的挖填方计算方法等;并利用IDL语言编制了基于激光点云数据的复杂工程挖填方计算软件LIDARVIEW,计算了唐海幸福花园复杂基坑工程不同设计高程的挖填方量。结果表明,该方法简单、快速、精度较高。

关键词：三维激光扫描复杂工程挖填方量移动最小二乘法 DEM

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生态服务价值与社会经济因素交互影响下的流域生态补偿标准研究

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水利学报 2024年第6期55卷 654-665页

作者：张剑付意成彭文启赵进勇朱启林中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038 北京市水务规划研究院北京101117

流域生态补偿是实现流域环境改善与区域经济均衡发展的一种政策工具,对消除上下游地区间的经济差异影响,实现区域社会发展的公平性具有重要意义。为定量寻求多元信息扰动下的流域生态补偿标准最优解,亟需开展基于多维关系协调及经济利... 详细信息

流域生态补偿是实现流域环境改善与区域经济均衡发展的一种政策工具,对消除上下游地区间的经济差异影响,实现区域社会发展的公平性具有重要意义。为定量寻求多元信息扰动下的流域生态补偿标准最优解,亟需开展基于多维关系协调及经济利益分配多目标优化求解的动态均衡博弈研究。以实现生态补偿标准讨价还价贝叶斯纳什均衡为目标,借助完全信息博弈的混合均衡策略实施过程探讨流域生态补偿标准均衡解存在条件,并基于流域上下游间的动态转移支付进行生态补偿标准均衡解求解,依托激励相容机制开展讨价还价的动态博弈贝叶斯均衡的合理性分析。本文结合弥河流域经济社会取用水费用标准及水资源使用价值的变化规律,在流域生态保护和社会经济发展基本均衡的情况下,下游的寿光市、中游的青州市对上游临朐县的水量-水质生态补偿额度分别为3194万元、859万元。本文给出的研究方法可用于处理博弈过程中的冗余信息以便于进行讨价还价,形成合理的流域生态补偿标准。

关键词：均衡博弈贝叶斯均衡讨价还价流域生态补偿标准效率性

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基于分形理论的多孔介质渗透注浆机制

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长江科学院院报 2024年第9期41卷 106-113页

作者：侯晓萍莫浩赵卫全黄勇西北农林科技大学水利与建筑工程学院陕西杨凌712100 西北农林科技大学旱区农业水土工程教育部重点实验室陕西杨凌712100 中国水利水电科学研究院北京100038 广东省水利电力勘测设计研究院有限公司广州510635

为研究宾汉姆浆液在多孔介质地层的渗透注浆机制,基于分形理论、毛细管模型和宾汉姆浆液流变方程,推导了基于分形理论的宾汉姆浆液渗透扩散表观速度公式和多孔介质渗透注浆球形扩散公式;利用已有的理论模型和室内渗透注浆试验成果对推... 详细信息

为研究宾汉姆浆液在多孔介质地层的渗透注浆机制,基于分形理论、毛细管模型和宾汉姆浆液流变方程,推导了基于分形理论的宾汉姆浆液渗透扩散表观速度公式和多孔介质渗透注浆球形扩散公式;利用已有的理论模型和室内渗透注浆试验成果对推导的理论公式进行了对比、分析和验证。研究结果表明:与传统的宾汉姆浆液渗透注浆扩散公式相比,基于分形理论的多孔介质渗透注浆扩散公式获得的浆液扩散半径更接近于室内试验成果。该研究成果可为实际多孔介质地层注浆工程提供一定的理论支撑。

关键词：多孔介质宾汉姆浆液分形理论渗透注浆表观速度扩散距离

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迂曲度对盾构隧道管片注浆的影响

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科学技术与工程 2024年第17期24卷 7319-7326页

作者：莫浩侯晓萍赵卫全黄勇西北农林科技大学水利与建筑工程学院杨凌712100 西北农林科技大学旱区农业水土工程教育部重点实验室杨凌712100 中国水利水电科学研究院北京100038 广东省水利电力勘测设计研究院有限公司广州510635

为了探究浆液扩散路径迂曲度对盾构隧道管片注浆效果的影响,以幂律浆液为对象,建立了考虑扩散路径迂曲度的盾构隧道管片注浆渗透扩散模型;分析了注浆时间、终止注浆压力和注浆速率对浆液扩散半径和管片所受压力的影响。最后,利用MATLAB... 详细信息

为了探究浆液扩散路径迂曲度对盾构隧道管片注浆效果的影响,以幂律浆液为对象,建立了考虑扩散路径迂曲度的盾构隧道管片注浆渗透扩散模型;分析了注浆时间、终止注浆压力和注浆速率对浆液扩散半径和管片所受压力的影响。最后,利用MATLAB与COMSOL Multiphysics软件,开发得到考虑扩散路径迂曲度的幂律浆液渗透扩散数值模拟程序,实现了盾构隧道管片注浆效果的可视化。研究结果表明:在其他参数不变时,终止注浆压力增大,则浆液扩散半径和管片所受压力均增大;随着注浆速率的不断增大,浆液扩散半径和管片所受压力先增大后减小。考虑浆液扩散路径迂曲度后,浆液扩散半径和浆液对管片的压力值较不考虑扩散路径迂曲度时减小,且随着终止注浆压力和注浆速率的增大,扩散路径迂曲度对扩散半径和管片所受压力的影响更加明显。

关键词：盾构注浆幂律浆液迂曲度渗透扩散

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Effects of artificially cultivated biological soil crusts on soil nutrients and biological activities in the Loess Plateau

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Journal of Arid Land 2014年第6期6卷 742-752页

作者： YanMin zhao QingKe ZHU Ping LI LeiLei zhao LuLu WANG XueLiang ZHENG Huan MA College of Water and Soil Conservation Beijing Forestry University Key Laboratory of Forest Ecology and Environment State Forestry Administration Research Institute of Forest EcologyEnvironment and ProtectionChinese Academy of Forestry Kunming Forest Exploration & design institute of State Forestry Agency Anhui Survey and design institute for Water {2. and hydropower planning and design {2. of Forest Products Industry State Forestry Administration

Biological soil crusts （BSCs） play an important role in the early succession of vegetation restoration in the Loess Plateau, China. To evaluate the effects of artificially cultivated BSCs on the soil surface micro-envir- onment, we obtained natural moss crusts and moss-lichen crusts from the Loess Plateau of Shaanxi province, and subsequently inoculated and cultivated on horizontal and sloping surfaces of loess soil in a greenhouse. The chemical and biological properties of the subsoil under cultivated BSCs were determined after 10 weeks of cul- tivation. The results indicated that BSCs coverage was more than 65% after 10 weeks of cultivation. Moss crust coverage reached 40% after 5 weeks of cultivation. Compared with the control, soil organic matter and available nitrogen contents in moss crust with the horizontal treatments increased by 100.87% and 48.2.%, respectively; increased by 67.56% and 52.17% with the sloping treatments, respectively; they also increased in moss-lichen crust with horizontal and sloping treatments, but there was no significant difference. Available phosphorus in cultivated BSCs was reduced, soil pH was lower and cationic exchange capacity was higher in cultivated BSCs than in the control. Alkaline phosphatase, urease and invertase activities were increased in artificially cultivated BSCs, and alkaline phosphatase activity in all cultivated BSCs was obviously higher than that in the control. Numbers of soil bacteria, fungi and actinomycetes were increased in the formation process of cultivated BSCs. These results indicate that BSCs could be formed rapidly in short-term cultivation and improve the mi- cro-environment of soil surface, which provides a scientific reference for vegetation restoration and ecological reconstruction in the Loess Plateau. China.

关键词： biological soil crusts soil nutrient enzyme activity soil microorganism Loess Plateau

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基于ERHIs法的雅鲁藏布江流域水文情势变化研究

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中国水利水电科学研究院学报（中英文） 2024年第1期22卷 108-119页

作者：杨靖蔺子琪赵庆绪谢静廖卫红华能西藏水电安全工程技术研究中心四川成都610093 四川大学水利水电学院四川成都610065 华中科技大学土木与水利工程学院湖北武汉430072 长江勘测规划设计研究有限责任公司湖北武汉430010 水利部水网工程与调度重点实验室湖北武汉430010 中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038

为探究变化环境下雅鲁藏布江流域环境流量组分与水文情势变化情况,采用改进后生态最相关水文指标ERHIs(The most Ecologically Relevant Hydrologic Indicators)、RVA(Range of Variability Approach)法定量分析了1965—2.18年间不同阶段不同环境组分下的雅鲁藏布江流域内水文情势的变化情况,并结合5种突变检验方法对指标进行验证。结果表明,通过EasyDHM插补数据是可行的,参数优化后的Nash系数最大为0.97,最小为0.67,均在合理范围内,在缺资料地区运用较好。针对雅鲁藏布江2.断面强变异指标改变度计算结果均表明雅江中下游地区的水文改变度为高度改变。在指标选取方面,生态水文改变过程的指标体系(Indicators of Hydrologic Alteration,IHA)参数之间的相关性较高,指标间的冗余问题十分突出。ERHIs指标具有一定的合理性,不仅有效缓解了IHA的冗余性问题,还有利于抓住最关键的生态水文变量,对生态水文研究、流域水资源管理和生态保护都具有重要的参考价值和借鉴意义,为短缺水文资料地区的生态评估提供参考。

关键词：水文改变度水文情势雅鲁藏布江生态最相关水文指标 EasyDHM模型

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