从三峡工程航运效益谈长江干流水电开发

长江是世界上内河航运最繁忙、运量最大的河流.当前长江干流水电开发正处于快速发展期.我们应借鉴国外上游梯级渠化,建坝必建闸,干流航道延伸,全线航道贯通,航道等级提高,干支航道联网的经验.三峡工程初期蓄水以来,库区航运条件明显改善,效果显著.对长江上游和金沙江下游的水电开发,一定要兼顾水电开发和航运发展,处理好两者的关系,做好水资源综合利用的文章.     

从三峡工程航运效益谈长江干流水电开发

长江是世界上内河航运最繁忙、运量最大的河流。当前长江干流水电开发正处于快速发展期。我们应借鉴国外上游梯级渠化，建坝必建闸，干流航道延伸，全线航道贯通，航道等级提高，干支航道联网的经验。三峡工程初期蓄水以来，库区航运条件明显改善，效果显著。对长江上游和金沙江下游的水电开发，一定要兼顾水电开发和航运发展，处理好两者的关系，做好水资源综合利用的文章。     

长江流域航运发展规划方案研究

长江航运存在通航等级偏低、航道潜能挖掘不足以及港口功能布局不合理等问题。论述了长江航运在综合交通运输体系中的战略地位和面临的发展机遇,提出了长江航运发展目标。根据已有的规划成果和流域水资源综合开发利用要求,提出了长江流域航道发展规划方案和港口建设规划意见：长江水系航道布局应以“一横十线一网”的国家高等级航道为骨架,地区重要航道为基础,其他航道为补充。长江水系主要港口布局应以流域性航运物流枢纽的上海、南京、武汉、重庆为中心,以其他主要港口为重点,形成长江港口主骨架,并辐射地区重要港口。     

妥善处理排涝河道与航运的矛盾

杭嘉湖南排,计划在海盐南台头、澉浦长山、盐官下河和盐官上河建4座排涝闸和1座电排站,并相应开4条排水干河,遇1954年型洪水,5至7月可排泄杭嘉湖地区涝水22.4亿立方米。南排工程的兴建,无疑对发展这一地区的航运有很大的好处。一是新开排水河道,增加了通航里程;二是排水河道一般有较大的底宽和水深,提高了航道等级,改善了通航条件;     

河道治理工程存在问题及对策分析

正我国幅员辽阔,水网密布,河流众多,水文差异较大。自古以来河道航运在我国的交通历史上起到了举足轻重的作用。但是航运也有自身的特点和限制:一是自然因素影响较大;二是长年累月的冲刷易形成淤堵,导致航道不通;三是一旦遇到洪涝灾害,往往受到灾害的威胁。当前我国的经济社会高速发展,公路、铁路和航空等运输手段不断完善和丰富,但航运仍然有着不可比拟的优点,在黄河中下游地区和长江大部分地区的运输手段中仍占有很大的     

水利水运紧相连——郭兴春副厅长谈湖北省水利、交通两部门合作情况

1985年元月,水利、交通两部在南京联合召开了综合利用水资源会议。这次会议,重新协调了两部间的关系,加强了合作。为了了解这方面的情况,笔者走访了湖北省水利厅副厅长郭兴春同志。这位年近花甲的老厅长,与他所从事的事业一样,熠熠生辉。他首先对笔者说:“水利水运紧相连,湖北的水利为水运发展创造了条件”。接着,他回顾了30多年来的工作,从发展水利这个基点出发,加固堤防,疏通河道,抬高水位,开槽去淤,兴修人工河等都兼有发展水运的效益,至少有8000公里河道,航运得到了改善。这是湖北省为水运发展所作的一大贡献。他告诉笔者,湖北历史上江、河、湖相通,河、湖、沟相连,有着发展航运的天然优势。但由于湖北大部分地区的中小河流尾闾入湖通江,水位随着长江、汉江主干流的涨落而起伏不定,落差较大,以致大部分河流只能季节性通航,且吨位较低。这不仅给航运带来困难,且给水利     

三峡工程为中下游河道实施生态及航道补水

目前长江干流河道进入枯水期,又逢湘江出现历史最低水位,鄱阳湖水面萎缩至丰水期的5%,武汉河道因枯水变成单行航道。根据长江上游流域来水情况及中下游生态、航运等用水需求,三峡工程从2011年12月31日开始实施补水调度,中下     

三峡工程与长江水资源利用

三峡工程控制长江流域面积１００万ｋｍ＾２，是开发利用长江水资源的关键工程。三峡 建设和运用，将有利于长江水资源的综合利用，在防洪、发电、航运、发展水产及旅游、改善环境、发展灌溉等方面发挥着 积极的作用     

荆汉生态新水道实施对长江中游航运的影响分析

针对长江干线航道"中梗阻"问题,学界提出了荆汉生态新水道的系统解决方案。通过梳理长江中游地区航运发展条件,从航道、港口、运输安全等方面,分析了荆汉生态新水道的实施对长江中游航运发展的综合影响。研究结果表明:(1)荆汉生态新水道的建设,在长江中游区域将形成"双通道"的运输格局,促进长江干线航道区段标准统一和区域高等级航道网络化,形成与长江上游地区的便捷通道,大幅提高长江干线大型船舶的通达程度,实现更高层次、更高水平的江海联运、江海直达运输。(2)新的深水岸线将为区域港口带来良好的发展条件,使高等级航道沿线港口枢纽作用得到增强,但对岳阳港会带来一定的不利影响。(3)提升区域航道通航的整体安全性,但会增加新老水道交汇区域的通航复杂性,给局部水域带来一定的安全风险。     

江苏省长江河道管理信息化设想

1 概述，江苏省长江干流总长433km．河道多呈典型的弯曲分汊型。随着水利建设与管理现代化的发展，大量的长江河道工程信息、水资源信息和管理信息，不能及时、准确、快速和科学地处理，将不利于长江河道管理的科学决策，因此有必要建立长江河道管理信息系统，用以为长江防汛、堤防管理和河道整治工程建设，以及岸线资源控制利用的现代化管理提供服务。     

Call for Papers

正As the eldest and most distributed professional journal of water industry,Water Wastewater Engineering(W WE)gained very wide acceptance from the colleagues working in this field in this country since start publication in 1964.Now it is administrated by the Ministry of Construction of the People’s Republic of China and sponsored by the China Civil Engineering Society etc.     

SPATIAL AND TEMPORAL WATER QUALITY VARIABILITY IN AQUATIC HABITATS OF A CULTIVATED FLOODPLAIN

The floodplains of lowland rivers contain diverse aquatic habitats that provide valuable ecosystem services but are perturbed when intensively cultivated. Hydrologic, water chemistry and biological (fish) conditions in five aquatic habitats along the Coldwater River, Mississippi, were measured for more than 4 years: the river, two severed meanders that functioned as backwaters, a managed wetland and an ephemeral channel draining cultivated fields. Off‐channel habitats were connected to downstream regions 0.10% to 32% of the dry season and 24% to 67% of the wet season. The median temperatures for the five monitored sites ranged from 18°C to 23°C, the median total solids concentration for all sites was 135 mg L^?1, the median total phosphorus was 0.29 mg L^?1 and the median total nitrogen was 1.56 mg L^?1. Chemical and physical water quality displayed strong seasonal differences between the wet winter/spring and the dry summer/fall periods so that temporal variation consisted of gradual seasonal trends superimposed on strong diurnal variations. All off‐channel habitats exhibited periods of hypoxia and temperatures >30°C during the dry season. Between‐site gradients of water and habitat quality were strongly coupled to water depth and runoff loading. The rehabilitation of one backwater by increasing water depth and diverting agricultural runoff was associated with improved water quality and fish species richness relative to an adjacent untreated backwater. The diversion of polluted runoff and the use of water control structures to maintain greater water depth were observed to be effective management tools, but the former reduces the water supply to habitats that tend to dry up and the latter reduces connectivity. Published in 2011 by John Wiley & Sons, Ltd.     

库水波动下库岸边坡地下水浸润线解析解及误差分析

解析法是库岸边坡地下水浸润线计算中便于实际应用的方法,但该方法须基于若干假定并对潜水运动基本方程线性化后才能求解。针对各假定和线性化过程建立不同的地下水渗流数学模型,用解析法和有限元法解答上述数学模型,分析各误差大小及其规律。结果表明:库岸垂直处理带来的误差要小于方程线性化处理和不考虑非饱和渗流带来的误差,而且它们都随渗透系数变大而减小;在三峡库区库水调度情况下,假定库水位等速变化带来的误差对大多岸坡而言可以忽略;计算库岸边坡地下水浸润线时,解析法只适用于水位变化幅度相比含水层厚度较小,且几何边界规则、岩土结构简单、岩土体渗透性较好时的情况。     

Spatio‐temporal variation of gross CO2 and CH4 diffusive emissions from Australian reservoirs and natural aquatic ecosystems,and estimation of net reservoir emissions

Carbon dioxide (CO₂) and methane (CH₄) diffusive emissions were measured during two field surveys in Queensland and Tasmania, Australia, using the floating chamber method. Bubbling and degassing emissions in 2010 were estimated in Koombooloomba Dam reservoir using only inverted funnels and gas concentrations, respectively. A total of 14 reservoirs and 16 rivers and lakes were sampled from 2006 to 2010. Spatial variation was substantial within each water body, as well as between them. The main drivers of diffusive emission variation were physiographic region and climate, with a clear demarcation being observed between diffusive emissions from tropical Queensland and temperate Tasmania, and between the humid West Coast Range (Tasmania) and dry Central Plateau (Tasmania). Higher CO₂ and CH₄ diffusive emissions were observed during the dry season, when long water residence times would promote organic matter degradation. Estimated total gross emissions, including diffusive, bubbling and degassing emissions, for Koombooloomba Dam reservoir were about 1.5 × 10⁶ t CO₂eq km² per year, or 24 × 10⁶ t CO₂eq per year. This corresponds to a plant emission factor of 3.18 kg CO₂eq MWh^?1. Using an estimate of terrestrial emissions derived from literature data for the Tully River catchment area, rough estimated net emissions from the catchment area are about 44 kt CO₂eq per year, or 5.83 kg CO₂eq MWh^?1, which is in the lower range of the studied reservoirs.     

Changes in Summer Irrigated Crop Area and Water Use in Southeastern Turkey from 1993 to 2002: Implications for Current and Future Water Resources

Changes in summer irrigated cropland acreage and related water use are estimated from satellite remote sensing and ancillary data in semi-arid Southeastern Turkey where traditionally dry agricultural lands are being rapidly transformed into irrigated fields with the help of water from the Euphrates-Tigris Rivers. An image classification methodology based on thresholding of Landsat NDVI images from the peak summer period reveals that the total area of summer irrigated crops has increased three-fold (from 35,000 ha to over 100,000) in the Harran Plain between 1993 and 2002. Coupled analysis of annual irrigated crop area from remote sensing and potential evapotranspiration based estimates of irrigation water requirements for cotton indicate a corresponding increase in agricultural water use from about 370 million cubic meters to over one billion cubic meters, a volume in accordance with the state estimates. These estimates have important implications for understanding the rapid changes in current agricultural withdrawals in Southeastern Turkey and form a quantitative basis for exploring the changes in future water demands in the region. For example, expansion of irrigated lands have led to a steady decrease in potential evaporation due to increased roughness and decreased humidity deficit in the Harran Plain. Assuming that the changes in future evaporation conditions will be of similar nature, water use for irrigation is expected to decrease over 40 percent in future irrigation sites. Incorporating this decrease in overall planning of the irrigation projects currently under construction should lead to improved management, and by extension, sustainability of water resources in the region.     

Site modelling methods for detecting hydrologic alteration of flood frequency and flood duration in the floodplain below the carlyle dam,lower Kaskaskia River,Illinois, USA

Reports concerning the influence of dams on river hydrology vary among researchers, interest groups and government agencies. These often contradicting statements may occur because changes in hydrology caused by dams are distinct for each dam and river watershed. The objective of this research was to use site specific techniques to determine if the 1967 installation of the Carlyle Dam, lower Kaskaskia River, Illinois, altered flood frequency and duration within the forested floodplain located below the dam. Results indicated a decrease in flood duration and frequency, and a decrease in annual flood frequency variation at a site 6.4 km below the dam. Pre‐dam versus post‐dam differences in flood frequency and duration at the site 32.2 km below the dam were related to climate rather than dam effects. Although dam impacts are a concern, this research shows that distance downstream from the dam and downstream tributary and watershed characteristics should be considered before assuming that the dam has changed hydrologic parameters for portions of rivers. This research also indicates that areas of the lower Kaskaskia River may still maintain hydrologic ecological integrity, and could be targeted for restoration and adaptive management purposes. Hydrologic modelling combined with river gage and on‐site well measurement techniques presented in this study could provide detailed flood frequency and duration information for land use, sociological and geomorphological questions in focus areas within river floodplains. Copyright © 2008 John Wiley & Sons, Ltd.     

浅谈优化Vray渲染在制作三维场景的应用研究

用Vray三维渲染引擎来渲染三维场景,其质量和速度是由一些影响因素和参数设置决定的,不同的参数和因素,可以得出不同的三维渲染效果.因此,分析、优化三维渲染质量和速度的影响因素,正确、合理的选择参数对提高Vray最后渲染阶段的质量和速度非常重要.     

固结、渗流和沉积控制方程研究

本文从两相流体动力学的守恒方程出发，考虑固相、液相的相对运动，推导了可以考虑场的不均匀性和流体压缩性的统一形式的控制方程，并对方程所基于的物理概念和相互联系进行了必要的分析。通过对方程适当形式的表达，可导出用于大、小变形固结、渗流和沉积的简化方程，显示了在不同领域的三个理论存在一定的统一性。方程推导过程并未对本构关系加以限制，适用范围较广。依据实际问题的要求，作了不同形式的简化。     

四川省及重庆市中型水电站效益分析

该文分析了四川省及重庆市几座中型水电站的调查材料表明：四川省及重庆市中型水电站不仅在川渝主网和地方电网中起着很大的作用，并具有巨大的社会效益，同时还有综合利用效益，说明修建中型水电站的优越性．     

Serial discontinuities in a Rocky mountain river. II. Distribution and abundance of trichoptera

River regulation in the headwaters and middle reaches of the Gunnison River, Colorado, significantly altered distributions and abundances of Trichoptera fauna. Twenty-five species were collected from mainstream samples, with the greatest species richness occurring at an unregulated, rhithron segment above the central reach dams. At sites immediately below the three hypolimnial-release dams and a reregulation dam, species richness was reduced 35–90 per cent and abundance > 95 per cent. Net-spinning caddisflies were the dominant trichopterans at unregulated sites; Arctopsyche grandis in the upper reaches (218 organisms, 586 mg dry mass m^?2) and Hydropsyche cockerelli, H. occidentalis and Cheumatopsyche pettiti in the lower river (9041 total organisms, 6621 mg m^?2), downstream from the last dam. The observed distributional pattern of low trichopteran densities in dam tailwaters and high hydropsychid densities at sites 60–80 km below the central reach dams is a classic expression of continuum resets and adjustments in response to stream regulation as predicted by the Serial Discontinuity Concept.