Chi river basin irrigation demand model

The calculation of irrigation demands and return flows is an essential component of the Chi Basin (Northeast Thailand) simulation model. The irrigation demand model is based on a simple field water balance so does not use the concept of effective rainfall. The paper describes the structure of the model. A sensitivity analysis on the model output is described.     

Effects of regulation on the flow regime of the river Murray,Australia

The flow regime of the River Murray has changed markedly over the last century, and especially the last 50 years, through increased diversions, construction of dams, weirs and levees and changes in operational procedures. A model developed by the Murray–Darling Basin Commission is used to compare simulated natural (unregulated) flows at eight stations with those at seven consecutive stages in the development of regulation. Monthly and annual average flows and coefficients of variation and skewness were computed, and the flow-duration, peak-flow and low-flow characteristics curves plotted. The results confirm that average monthly and annual flows are now considerably lower than those which prevailed under natural conditions. The seasonal distribution of flows has changed in the upper Murray, owing to the influence of dams. Flow-duration characteristics now vary considerably along the river, whereas there was little change under natural conditions. The effect of regulation on flow-duration characteristics is minimal at Albury and becomes more pronounced downstream; it is most apparent in regard to flows exceeded 20–80% of the time. The magnitude of average annual floods (annual exceedance probability 50%) has been reduced by over 50% at all stations, but big floods (average recurrence interval 20 years or more) are little affected. Further, the low flows for a given annual non-exceedance probability are higher under regulated conditions than those under natural conditions. These changes have profound implications for communities of native plants and animals in both riverine and floodplain environments, and also for the long-term utility of the river as a resource.     

腰堡灌区土壤次生盐渍化及其治理对策研究

位于大项子山航电枢纽上游松花江北岸的低、高漫滩区上的腰堡灌区,具有地形狭长临江、岩层透水性良好、地下水埋深浅、与江水位和高阶地水力联系密切等特点,使得由江水位升高引起的两岸地下水位壅高浸没现象备受关注,随之而来的次生盐渍化问题也越来越明显的表现出来.在梳理研究区自然地理概况的基础上,根据该区舍水层结构特征及地下水位、地...     

新疆玛纳斯河灌区农业水价承受力调查

按现行水价政策和国家产业政策,农业供水实行成本定价,从理论上讲,既符合国家政策又能被农户接受,但现实工作中供水成本难以得到用户承认或接受.在对灌区内典型单位具体农户实际调研的基础上,对农业生产成本、效益进行了分析,确定了农业用水的水价承受能力,提出提高农户对水价承受能力的对策.     

北京市农业节水灌溉成效存在问题及发展对策

针对北京市农业节水灌溉、设施农业和再生水灌区发展现状以及节水灌溉存在的主要问题进行了分析,并以此分析为基础,提出今后一段时间内,农业节水灌溉发展对策,即构建农业灌溉高效节水体系和农业水资源科学管理体系。山区重点围绕特色林果、绿色养殖、生态旅游三大主导产业发展节水;平原近郊区围绕都市型现代农业以井灌区节水改造和建设再生水灌区为重点,调整用水及农业种植结构,提高灌溉水利用效率。     

灌区岩土结构分类及灌区工程地质评价方法

以江西省廖坊灌区工程地质勘察为例,对灌区岩土结构分类方法进行了探索．灌区岩土结构分类能更方便地分辨出哪些岩土结构类型存在什么样的工程地质问题,哪些不存在工程地质问题．同时能更好地为设计、施工及后续的灌区工程管理提供地质依据．     

Effects of river regulation on flooding of a riparian red gum forest on the River Murray,Australia

Forests of river red gum (Eucalyptus camaldulensis Dehnh.) occur along the River Murray in Australia. These forests are important for biota, recreation, grazing, and wood products. They occur in a sub-humid to semi-arid environment and require flooding for adequate growth and regeneration. The largest continous area is the Barmah (Victoria) and Millewa (New South Wales) forest near Echuca (Vic.). Information from maps showing the extent of inundation of Barmah Forest for particular floods was related to flow data upstream of the forest, and maps showing the distribution of vegetaton and forest site quality. Vegetation associations were shown to occur in characteristics flood frequency ranges, with red gum being the dominant species on all but the highest and lowest flood frequency sites. In general, higher red gum site quality was associated with higher frequency of flooding. The extent of flooding depended on the magnitude of peak flows in the river. Regulation of the river since the first filling of Hume Dam in 1934 has caused a reduction in the frequency of flows associated with partial flooding and an increase in the occurrence of small summer floods. Areas with a high flood frequency were most affected. It is possible that the forest may change to types associated with reduced duration of inundation in the long-term unless ameliorative action is taken.     

江西省灌区内农业灌溉配水到户方法研究

借鉴国内外有关水权及水量分配方面的研究成果,分析江西省灌区现状及存在的问题,重点分析目前江西省农业灌溉配水到户的难点,在此基础上研究适合江西省农业灌溉配水到户的技术路线及方法.为探索南方灌区的水资源合理分配方式提供依据和方法.     

淠史杭灌区水稻灌溉效益的分析研究

水稻是淠史杭灌区的主要粮食作物，随着现代农田灌溉和农业先进技术的推广应用，产量不断提高，其增产效益显然是水利和农业综合作用的结果。为了水利工程的经济分析，制定合理的水价标准，淠史杭灌区灌溉试验站按丰水年、平水年、干旱年和特别干旱年4个典型降雨年型试验分析灌区供水的灌溉效益。通过试验结果分析，并根据灌区历年降雨和粮食产量资料，按降雨频率测算各年灌溉效益分摊系数，计算出灌区的农业供水灌溉效益。     

Historical review of river improvement works in the Tone river basin

This paper traces the history of improvement works in the Tone basin, which includes Tokyo, as background to an understanding of river management in Japan today. After outlining the hydrogeographical features of the area, the author describes how the course of the Tone has changed, first naturally and later by design. Artificial alterations were made variously for the purposes of transportation, land reclamation, military defence and flood protection. Rivers are no longer important highways, but flooding remains an ever‐present danger.     

位山灌区用水户参与管理的实践探索

位山灌区是全国第五大灌区。近年来,灌区以现有的乡级灌区管委会为依托,在工程配套率和完好率比较高、群众基础扎实的支渠开展了用水户参与灌溉管理的试点。灌区通过广泛宣传、循序渐进、加强田间工程配套、找准突破口和建立用水户协会的保障体系,扎实推进灌溉工程管理制度改革,明确了今后的改革发展思路。     

一种水下割草机的研制与应用

针对灌区工程中灌排渠道普遍存在水草生长泛滥、堵塞渠道、降低过水能力、影响水质、污染环境等问题,研制出能在灌排渠道及池塘等水域中进行割草清除的一种水下割草机,经过江西省锦北灌区的试验与运用,效果良好,对灌排渠道的清草疏浚具有推广价值.     

节水灌溉与农业种植结构调整

在水资源日益匮乏的情况下,以优化品种、提高质量、增加效益为中心的农业种植结构调整,必须建立在节水的前提下。发展节水高效农业,是实现水资源可持续利用、农业可持续发展的根本措施。     

探讨大型灌区节水续建配套项目建设中存在的问题

具有卓越节水能力的大型灌区节水续建配套项目建设已在被普遍推广。它不仅提高了水的利用率、抗涝抗洪等抗灾能力强、提高了农业综合生产能力而且美化环境保护生态。本文针对大型灌区节水续建配套项目建设的各主要阶段包括项目的规划评估、招标投资、施工验收和管理维护等可能存在的问题进行了探讨并提出了具有针对性的建议。     

GIS支持下的江西省农田节水灌溉系统研究

以GIS技术支持下的江西省农田节水灌溉系统为研究对象,阐述了系统研究的主要内容、方法和技术框架,并对GIS技术在节水灌溉中应用的特点及优势进行了分析。     

Thermal Convection in the Great Artesian Basin,Australia

High groundwater temperatures at shallow levels have been recorded inthe Great Artesian Basin, Australia. In the most part of the Basingeothermal gradients are above the global average. It is suggestedthat geothermal gradients determine the groundwater flow patterns inthe Basin aquifers. Six extensive regions where Rayleigh numbersexceed the critical value for the onset of thermal convection areidentified. Further numerical experiments with parameters derived fromfield observations show that thermal convection can actually occur inthese regions. The identified convective regions are large in size (ofthe order of 100 km horizontally) and coincide with importantgroundwater management zones. Within the convective regions thegroundwater flow is not horizontal but has a significant verticalcomponent. Thermally-induced vertical flows result in intensive masstransfer within and between aquifer layers. In the groundwatermanagement context, the latter means a higher degree of vulnerabilityof the Basin aquifers. Numerical models with incorporated couplingbetween heat and mass transfer processes are shown to be appropriatefor the impact assessment of management strategies in the Basin.     

谈如何进行灌区农业灌溉配水到户——以金临渠灌区为例

探讨灌区农业灌溉配水到户的工作内容、主要技术思路和方法,并以江西省金临渠灌区为例,强调了灌区农业灌溉配水到户应注意的几个重要问题,同时提出了开展灌区农业灌溉配水到户工作相关的一些建议．     

Use of coal seam water for agriculture in Queensland,Australia

The development of the coal seam gas industry in Australia has led to the extraction of large volumes of relatively salty groundwater. Once treated, this coal seam water (CSW) is being made available for irrigation and it is an opportunity for landholders to increase the level and reliability of their agricultural production. This paper reviews the use of CSW and approaches to sustainable agriculture. The review suggests that, barring technical and economic constraints, re-injection of treated CSW into stressed agricultural aquifers may provide more equitable access to water and broader economic benefits than current location-specific irrigation schemes.     

灌区渠道衬砌型式设计选择

本文从衬砌材料、断面形式、防渗效果、工程造价及施工设计等方面,对常用渠道衬砌型式的优缺点进行了分析比较。预制U型槽占地面积较小,造价较小,易施工,且当地渠道预制U型槽衬砌应用较广泛,有较好的设备和技术实力,由此推荐预制U型槽作为斗渠和农渠的渠道衬砌型式。     

灌区现状分析评价探讨

采用权重综合评价方法对灌区现状进行定量分析,介绍了选择评价指标和确定指标的权重的方法,并对广西大型灌区进行分析评价.