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IMPACT ASSESSMENT OF THE LIUJIAXIA DAM OPERATION ON THE FLOW REGIME OF THE LANZHOU REACH IN THE UPPER yellow river

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IMPACT ASSESSMENT OF THE LIUJIAXIA DAM OPERATION ON THE FLOW...

水电2006国际研讨会

作者： Sun Zhaodong1, Gao Chuande2, Xu Zhixiu3. Gou Wande4, Li Xiuyun5 1, 2, 3.yellow river water {3. Protection Institute, 12 Chengbei Road East, zhengzhou 450004, china sunzd2003.4, Upper Reaches Bureau of Hydrology and water {3. of YRCC, Lanzhou 73.03., china 5,Juancheng Countywater Affairs Bureau,274600,china

There are several constructed dams such as Qingtongxia, Liujiaxia, Qingtongxia, etc. on the main trunk of the Upper yellow river. After the Liujiaxia dam operation, the natural flow regime of Lanzhou reaches has been altered. In order to assess degree of the alteration of the natural flow regime, the RVA method and the hydrological series of daily mean flow rate at Lanzhou Station from 193. to 2001 are used to analyze the alteration of 3. ecologically relevant hydrologic parameters （IHAs）. The management objective based on RVA is not to have the river attain the target range every year;rather, it is to attain the target range at the same frequency as occurred in the natural or pre-development flow regime. In the analysis, the 25th and 75th percentile values of each hydrologic parameter are used as RVA boundaries computed from pre-dam hydrological series. The range of each parameter is divided into three categories: high, middle and low. The middle category is defined as management target, that is, the attainment of RVA target of a particular parameter would be expected in only 50% years. The degree to which the RVA target is not attained （a measure of hydrologic alteration） is computed. The degree values of all of 3. IHAs are used to assess the degree of overall alteration. The result shows that the natural flow regime has been influenced by the operation of Liujiaxia dam and the alteration belongs to overall high alteration. In the 3. IHAs, 14 parameters such as the mean flow rate of August, September, October, December, January, March and June, 90-day minimum flow rates, base flow, low flow pulse count, low flow pulse duration, rising rate, falling rate and number of reversals belong to high alteration. The ecological integrity of river ecosystems depends on their natural dynamic character. Viewing from maintaining the ecological integrity of yellow river ecosystems, hydropower station operation must regard maintaining the natural flow regime bellow its dam in the

关键词： flow regime impact assessment dam operation upper yellow river.

Transformation of Unit Current Power by Experiment on Loess Slope

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Transformation of Unit Current Power by Experiment on Loess ...

海峡两岸三地环境与资源学术研讨会暨第二届中国环境资源与生态保育学会会员代表大会

作者： SHEN Zhenzhou~(1,2),YAO Wenyi~2,LI Zhanbin~(*1) 1.Institute of water resources and Hydro-elcetric Engineering,Xi'an University of Technology,Xi'an P.R.china 710049 2.Key Laboratory of {3. river Sediment Research,{3. river Institute of Hydraulic Research,YRCC,MWR,zhengzhou P.R.china 4.0003

The unit current powers have some disorder in different water drainage,they undulate between 0.02 - 0.14m/s,0.05 - 0.3.m/s,0.15 - 0.55m/s in different grades slope;on 20°￡lope,the unit current power waved steady with time in 1,2 and 3./min water drainage amount,the unit current powers decreased gradually first,and then got the waved steady in 4L/min water drainage amount,about 0.1 m/s;the unit current power was increasing -decreasing-waved steady in 5,7.5 and lOL/min water drainage amount;The unit current powers are increasing with slope grade increase except individual *** the initial stage,the unit current powers of 20°and 3.°slope were closed,they increased firstly and then decreased,were bigger than 10°slope which was waved steady,the unit current powers of 20°and 3.°slope got waved steady at 18min at 5L/min water drainage amount;they got the waved steady at 1 Omin,were 4 rimes of unit current powers on 10°slope at 7.5L/min water drainage amount.

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基于多尺度下AR(P)耦合预测模型的应用研究

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四川大学学报（工程科学版） 2004年第5期36卷 16-19页

作者：张少文张学成万星王玲丁晶四川大学水电学院四川成都610065 黄河水文水资源研究所河南郑州450044 成都信息工程学院电子系四川成都610051

基于多尺度分析理论,运用Mallat算法和Daubechies小波,把时间序列分解为比原始序列更单一的细节和概貌部分,并利用AR(P)模型能反映时间序列中邻近时刻间联系的特性,对序列分解后的部分进行拟合与预测,然后再由多尺度分析中的重构方法进... 详细信息

基于多尺度分析理论,运用Mallat算法和Daubechies小波,把时间序列分解为比原始序列更单一的细节和概貌部分,并利用AR(P)模型能反映时间序列中邻近时刻间联系的特性,对序列分解后的部分进行拟合与预测,然后再由多尺度分析中的重构方法进行序列重构,由此建立耦合的预测模型。通过黄河青铜峡270多年(1724～1997)年径流时间序列的建模及验证,表明拟建的耦合模型与传统单一模型的预测精度相比,由50%提高到90%,可用于实际需要。

关键词：多尺度分析 Maual算法 Daubechics小波 AR(P)模型耦合预测天然年径流

关于“黄河三角洲生态保护修复情况”的民主监督报告

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中国发展 2024年第1期24卷 81-85页

作者：致公党山东省委会于鹏中国致公党山东省委员会山东济南250014 不详

黄河三角洲作为我国暖温带保存最完整、最广阔、最年轻的湿地生态系统,拥有河海交汇、新生湿地、野生鸟类三大世界级生态景观,是黄河流域重要的生态功能区,在世界河口湿地生态系统中极具代表性,对于保持河海生态系统平衡、调节气候、蓄... 详细信息

黄河三角洲作为我国暖温带保存最完整、最广阔、最年轻的湿地生态系统,拥有河海交汇、新生湿地、野生鸟类三大世界级生态景观,是黄河流域重要的生态功能区,在世界河口湿地生态系统中极具代表性,对于保持河海生态系统平衡、调节气候、蓄洪防旱、提高生物多样性、维护区域生态安全具有重大意义。黄河三角洲生态环境脆弱,生态问题复杂多样、相互交织,生态系统恢复难度大、过程缓慢、稳定性较差,退化风险仍然存在,保护形势依然严峻。为此,致公党山东省委会牵头围绕黄河三角洲生态保护修复开展民主监督调研。调研发现,目前制约黄河三角洲生态保护修复主要问题有规划政策和要素支撑体系不完善、水资源开发利用问题突出、生态工程成效仍不稳固、生物多样性保护压力较大、盐碱地综合利用矛盾较多等。建议从强化规划引领和要素保障、加强水资源节约集约利用、巩固生态保护修复成果、加快实施黄河三角洲生物多样性保护重大工程、科学开展盐碱地综合利用等方面加强黄河三角洲生态保护修复。

关键词：黄河三角洲生态保护修复民主监督

小浪底水库库区支流东洋河及西阳河泥沙淤积规律分析

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水电能源科学 2011年第10期29卷 85-87页

作者：祁志峰屈章彬焦玉峰曲少军小浪底工程咨询有限公司河南郑州450000 小浪底水利枢纽建设管理局水力发电厂河南济源459017 黄河水利科学研究院河南郑州450003

针对小浪底水库蓄水后泥沙淤积影响支流淤积的问题,以小浪底水库库区支流东洋河、西阳河为例,介绍了干流及支流泥沙观测断面的布置及测验方法,并分析了东洋河、西阳河泥沙淤积观测结果。结果表明,干流三角洲淤积体已在支流河口形成了拦... 详细信息

针对小浪底水库蓄水后泥沙淤积影响支流淤积的问题,以小浪底水库库区支流东洋河、西阳河为例,介绍了干流及支流泥沙观测断面的布置及测验方法,并分析了东洋河、西阳河泥沙淤积观测结果。结果表明,干流三角洲淤积体已在支流河口形成了拦门沙坎,致使支流河底纵向坡度变小甚至变为倒坡,这对小浪底水库运行及黄河干流及其支流排沙将产生不利影响,有必要深入研究并提出防治措施。

关键词：库区支流泥沙淤积规律

Effect of water Supply Pressure on Soil water Movement in Different Soil Textures under Subsurface Irrigation with Porous Pipe

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Effect of Water Supply Pressure on Soil Water Movement in Di...

国际农业工程大会

作者： Zuoxin LiuProfessor Ph.D Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 china Yichang WeiEngineer Ph.D yellow river Basin {3. resources Protection Bureau zhengzhou 450004 china Tel. 0086-3.1-6022646 Fax 0086-3.1-6020711Lingling RangSenior Engineer M.S. yellow river Institute of Hydraulic Research zhengzhou 4.0003.china Guifang LiSenior Engineer B.S. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 china

＜正＞ With the help of HYDRUS-2D computer program, the numerical simulation of soil water transport was conducted within the pressures of water supply from 100 cmH2O to 1000 cmH2O in different soil textures of Meadow Brown Soil under subsurface irrigation with porous pipe in the paper. Results showed that numerical simulations were convergent under the water supply pressure within 100-1000cmH2O in loam soil, 100-600 cmH2O in loam sand soil and 100-400 cmH2O in clay soil, respectively. The time for the wetting front of

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Large-scale Hydropower Station Economic Dispatch Based on Immune Algorithm

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Large-scale Hydropower Station Economic Dispatch Based on Im...

第二十六届中国控制会议

作者： Xu Chenguang1,Zhao Maihuan 2 1.Department of Geotechnical Engineering,North china Institute of water Conservancy and Hydroelectric Power,zhengzhou 450011,P.R.china2.yellow river Engineering Consulting Co.,Ltd,zhengzhou 4.0003.P.R.china

In accordance with the characteristic of large-scale hydropower stations,a minimum-water-consume model was proposed and Immune Algorithm（IA）was used to solve Economical Operation of Hydropower Plant（EOHP）in this *** the result obtained by IA with those obtained by Genetic Algorithm（GA）and Evolutionary Programming（EP）in a case study,IA showed its effectiveness and good global search *** IA was better than GA in solving EOHP problem.

关键词： water management Economical Operation of Hydropower Plant Evolutionary Algorithm Immune Algorithm

A MATHEMATICAL MODEL FOR UNSTEADY SEDIMENT TRANSPORT IN THE LOWER yellow river

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International Journal of Sediment Research 2001年第2期16卷 150-158页

作者： ZHANG Hongwu1, HUANG Yuandong1 and ZHAO Lianjun2 1 Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, china 2 yellow river Institute of Hydraulic Research,{3. Department of Hydraulic Engineering Tsinghua University Beijing 100084 China yellow river Institute of Hydraulic Research Zhengzhou 450003 China

A one-dimensional mathematical model for unsteady sediment transport in the Lower yellow river is developed. A coefficient of sediment distribution is defined to represent the ratio of the bottom to the average concentration under the equilibrium conditions. The coefficient is not constant and is evaluated by using an empirical expression obtained by integrating the sediment concentration along water depth. The concentration distributions and the mean diameter distributions of suspended sediment in the transversal direction are also estimated in this model. A four-point (Preismann type) finite difference scheme and TDMA are employed in the numerical method. Three typical floods occurd in 1977,1982 and 1996, respectively, in the Lower yellow river from Tiexie to Shunkou with a length of 3.3.67km are numerically simulated with the model. The computed results, such as the water stage, discharge, and sediment concentration agree well with the measured data.

关键词： Mathematical model Unsteady sediment transport The Lower yellow river Floods

不同数据驱动模式下三峡长期径流预测比较研究

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水电能源科学 2010年第12期28卷 8-9,29页

作者：唐林钟平安黄河勘测规划设计有限公司国际工程设计院河南郑州450003 河海大学水文水资源学院江苏南京210098

采用周期均值叠加和小波分析长期预测径流方法,并选择横向与纵向数据驱动模式,对比分析了三峡入库径流长期预测效果。结果表明,周期均值叠加法优于小波分析方法、枯水季节纵向数据驱动模式优于横向、汛期横向优于纵向,采用两种数据驱动... 详细信息

采用周期均值叠加和小波分析长期预测径流方法,并选择横向与纵向数据驱动模式,对比分析了三峡入库径流长期预测效果。结果表明,周期均值叠加法优于小波分析方法、枯水季节纵向数据驱动模式优于横向、汛期横向优于纵向,采用两种数据驱动模式的组合预测年径流的精度更高。

关键词：三峡水库径流预测数据驱动模式周期均值叠加小波分析