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1.
This paper describes the essential contents of research at a recently completed subsurface pipe drainage project located in
the Khushab district of Pakistan. The paper explores the need and decision by Government of Pakistan to install a Sub Surface
Pipe Drainage Project near Khushab where an old Surface Drainage System was already installed by the Provincial Irrigation
and Power Department, Government of Punjab, Pakistan, since 1960. The new Sub Surface Pipe Drainage Project’s planning and
executing agency M/S Euro-Consultant used existing Surface Drains with remodeling for to carry the additional drainage effluent
of newly constructed sump pumps of the pipe drainage system connected to the old drains by means of small outfall drains.
Until now the new system is working well in lowering the water table as well as increasing the agro-socio-economic status
of the local population. 相似文献
2.
Subsurface drainage has been implemented in irrigation areas of South-eastern Australia to control water logging and land salinisation. Subsurface drainage has been identified as a major salt exporter from irrigated areas. The water table management simulation model DRAINMOD-S was evaluated to simulate daily water table depth, drain outflow, and salt loads by using experimental field data from a two year field trial was carried out in the Murrumbidgee Irrigation Area South-eastern Australia to study different options for subsurface drainage system design and management to reduce salt load export. Three subsurface drainage systems were modeled, deep widely spaced pipe drains, shallow closely spaced drains and deep pipe drains that were managed with weirs to prevent flow when the water table fell below 1.2 m. The reliability of the model has been evaluated by comparing observed and simulated values. Good agreement was found between the observed and simulated values. The model confirmed the field observations that shallow drains had the lowest salt load and that by managing deep drains with weirs salt loads could be significantly reduced. This work shows the value of the DRAINMOD-S model in being able to describe various drainage design and management strategies under the semi-arid conditions of South-eastern Australia. The model can now be used to investigate design and management options in detail for different site conditions. This will assist decision makers in providing appropriate subsurface drainage management policies to meet drainage disposal constraints within integrated water resources management planning. 相似文献
3.
B. Lesaffre 《Irrigation and Drainage Systems》1989,3(2):181-191
Subsurface drainage annual rate boomed in France in late 70s and reached a steady rate of 130 000 hectares in 1982. As a consequence,
better knowledge of drainage requirements, techniques and effects on farm management is requested.
Emphasis has been put on preliminary survey planning. First of all extension and location of areas to be drained is determined
with the help of farmers and local representatives within so-called “local juries”. Secondly, drainage recommandations are
derived using the so-called “soil reference area” method.
Drainage criteria and design methods are discussed on the basis of recent field experimental results. Drain spacing computation
is related to tail recession stage; soil hydraulic properties are measured in situ using Guyon's pumping test. Subsurface
and arterial drainage design rate are related to discharge exceedance duration curves and annual level of protection. 相似文献
4.
An assessment of project management software as a decision support system for irrigation management in Morocco 总被引:1,自引:0,他引:1
The characteristics and potential of project management software as a tool for improved planning and management of on-going irrigation operations are assessed. A commercially available package was tested through use for the simulated planning of the close season maintenance campaign of major pump stations at a large scale irrigation scheme in Morocco. The software was found to be well suited to this planning activity and successfully helped resolve conflicts in terms of time and resources available. Its potential as a tool for sensitivity analysis and for monitoring and control was clearly demonstrated. The exercise had an immediate effect on management decision making and managers concerned have adopted the software for further trials. The approach is recommended as a means to enhance planning, communication and teamwork for suitable irrigation management operations, but will be most effective with the development of supporting databases to enhance the quality of planning data used. 相似文献
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农田除涝排水技术研究综述 总被引:2,自引:0,他引:2
从农田涝灾风险评估、农田除涝排水工程技术、农田除涝排水管理3个方面入手,综述了近年来国内外取得的相关研究成果,并对农田除涝排水技术研究的未来发展进行了展望.明确指出未来的重点方向是:研究变化环境下的农田涝灾演变规律,构建人工-自然复杂条件下的农田涝灾预测评估技术与方法;研究满足作物产量需求和环境保护要求的农田涝灾综合控制标准,提升传统农田除涝治理技术水平与管理模式,探讨现代化除涝技术与传统除涝技术相结合的技术体系;重视农田排水资源的高效利用,研究适宜不同类型区的节水灌溉与控制排水相结合、灌溉排水与沟塘湿地调蓄净化相结合、排水资源循环灌溉再利用与除涝抗旱相结合的农田排水管理模式. 相似文献
7.
《Journal of Agricultural Engineering Research》1999,72(1):19-25
Drainage properties of and ammonia emissions from slatted floors and drainage channels were investigated using a laboratory arrangement development for the purpose. The arrangement consists of a steel-framed box with two levels in order to simulate different slatted floor systems. The slatted floor under test is laid on the top level and manure is dropped on to it from various heights. The lower level consists of a drainage channel, the top of which is covered by a lid perforated with holes of different shapes.Drainage experiments on slatted floors for cows with slits from 30 to 45 mm wide showed an average total drainage value for faeces and urine of 72% and an average urine drainage value of 82%. Drainage experiments on slatted floors for pigs showed results varying between 38 and 46% for total drainage depending on different drainage arrangements. The best drainage capacity was obtained when the drainage channel cover had holes giving a large drainage area.The ammonia experiments on slatted floors for cows with 2 and 30 mm spacing showed an accummulated ammonia emission of about 8 and 3 g respectively, during the 20 h testing period. On slatted floors for fattening pigs, the accumulated ammonia emission was calculated to be about 2 g during the 20 h testing period. These ammonia emission results are related to the mass quantities and the nitrogen contents of faeces and urine, which normally are dropped to slatted floor surfaces in animal buildings. 相似文献
8.
《Agricultural Water Management》1996,29(3):235-253
The performance of published pedotransfer functions was evaluated in terms of predicted soil water content, pressure heads, and drainage fluxes for a layered profile. The pedotransfer functions developed by Vereecken et al. (1989), Vereecken et al. (1990) were used to determine parameters of the soil hydraulic functions θ(h) and K(h) which were then used as input to SWATRER, a transient one-dimensional finite difference soil water model with root uptake capability. The SWATRER model was used to simulate the hydraulic response of a multi-layered soil profile under natural climatic boundary conditions for a period of one year. The simulations were repeated by replacing the indirectly estimated water retention characteristic by (1) local-scale, and (2) field-scale mean observed θ(h) relationships. Soil moisture contents and pressure heads simulated at different depths in the soil profile were compared to measured values using these three different sets of hydraulic functions. Drainage fluxes at one meter below ground surface have also been simulated using the same three sets of hydraulic functions. Results show that simulations based on indirectly estimated moisture retention characteristics (obtained from pedotransfer functions) overpredict the observed moisture contents throughout the whole soil profile, but predict the pressure heads at shallow depths reasonably good. The results also show that the predicted drainage fluxes based on estimated retention functions are about four times as high compared to the drainage fluxes simulated using measured retention curves. 相似文献
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Mahmoud M. Moustafa 《Irrigation and Drainage Systems》1998,12(2):141-159
Drainage water from the lower boundary of the root zone is an important factor in the irrigated agricultural lands for prediction of the water table behavior and understanding and modeling of water and chemical movement in the soil profile. The drainage coefficient is an important parameter for the design of subsurface drainage. On a 33,138 ha of the Nile Delta in Egypt, this study is conducted using 90 irrigation periods over a 3-year crop rotation to estimate the time-dependent drainage from the root zone and the design subsurface drainage coefficient with different cropping seasons and irrigation management levels.The results showed that the cropping seasons and the irrigation management levels as indicated by different irrigation efficiency are significantly affected the drainage rate from the root zone and the design value of subsurface drainage coefficient. Drainage rates from the root zone of 1.72 mm/d and 0.82 mm/d were estimated for summer and winter seasons, respectively. These rates significantly decreased in a range of 46% to 92% during summer season and 60% to 98% during winter season when the irrigation efficiency is increased in a range of 5% to 15%. The subsurface drainage coefficient was estimated to be 1.09 mm/d whereas the design drain pipe capacity was estimated to be 2.2 mm/d, based on the peak discharge of the most critical crop (maize), rather than 4.0 mm/d which is currently used. A significant decrease of the drainage coefficient and the drain pipe capacity ranges from 18% to 45% was found with the increase of irrigation efficiency in a range of 5% to 15%. The leaching requirement for each crop was also estimated. 相似文献
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Drainable surplus assessment in irrigated agriculture: field application of the groundwater approach
To assess the drainable surplus of an irrigated area, a methodologybased on a groundwater-balance approach was developed and appliedin Schedule I-B of the Fourth Drainage Project near Faisalabad inPakistan. To determine the seasonal net recharge in this area, anumerical groundwater model was run in inverse mode. The data inputfor the model consisted of the geometry of the aquifer system, theaquifer parameters, and historical watertable elevations. The seasonalnet recharge values, calculated from the individual recharge anddischarge components, were tuned with the results of the inversemodelling. The advantage of such an integrated approach is that allthese components are linked. The design net recharge was estimatedfrom the historical net recharge of the wettest monsoon in the studyperiod. Its rainfall recharge values were then substituted for those of adesign monsoon. In this substitution procedure, the rainfall rechargemethodology and parameters were adopted from the tuning procedure.From this design net recharge, estimates could be made of the requireddrainable surplus, with and without drainage simulation. 相似文献
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我国进入快速发展阶段之后,城市化进程也在进一步加快,而在这一段时间之中出现的土地资源紧缺的问题就浮现出来,并逐步发展成寸土寸金的局面。土地管理部门需要准确地把握土地实际情况,这样才可以实现土地资源的合理开发与设计。在规划之中,土地测绘作为其技术支持,在信息化技术普及的过程中,让测绘技术获取准确的数据支持。因此,就信息化测绘在土地开发管理之中的应用进行分析,以满足土地的开发管理需求。 相似文献
15.
An integrated hydro-economic modelling framework to evaluate water allocation strategies I: Model development 总被引:2,自引:0,他引:2
Biju George Hector MalanoBrian Davidson Petra HellegersLuna Bharati Sylvain Massuel 《Agricultural Water Management》2011,98(5):733-746
In this paper an integrated modelling framework for water resources planning and management that can be used to carry out an analysis of alternative policy scenarios for water allocation and use is described. The modelling approach is based on integrating a network allocation model (REALM) and a social Cost Benefit economic model, to evaluate the physical and economic outcomes from alternative water allocation policies in a river basin or sub-basin. From a hydrological perspective, surface and groundwater models were first applied to assess surface and groundwater resource availability. Then an allocation model was applied to reconcile the calculated surface and groundwater resources. From an economic perspective initially the value of water allocated to different uses in each demand centre within the system was estimated. These values were then placed in a social Cost Benefit Analysis to assess the economic consequences of different allocation scenarios over time and space. This approach is useful as it allows policymakers to consider not only the physical dimensions of distributing water, but also the economic consequences associated with it. This model is considered superior to other models as water is increasingly being seen as an economic good that should be allocated according to its value. The framework outlined in this paper was applied to the Musi sub-basin located in the Krishna Basin, India. In applying this framework it was concluded that competition for Musi water is very high, the transfer of water from agriculture to urban users is likely to grow in future and the value of water used in different agricultural zones is very low. 相似文献
16.
水资源信息化是我国水利“十五”计划中 ,调整从工程水利向资源水利转变 ,建立实施的五大水利信息系统重点之一。根据水资源信息采集的特殊性、管理需求的实用性、资源发展过程中的动态性与水资源需求的可持续性 ,论述了水资源 MIS的可行性框架结构、支撑平台和工具技术等设计要素。可供水资源 MIS管理信息系统方案规划和实现参考 相似文献
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The achievement of sustainable irrigation in arid regions requires greater attention to waterlogging, salinization, and degradation of ground and surface waters, which are among the problems that continue to threaten productivity and degrade environmental quality. We consider sustainability to be achieved when irrigation and drainage are conducted on-farm, and within irrigation districts, in a manner that does not degrade the quality of land, water, and other natural resources, either on-farm or throughout an irrigated region. Sustainability may also be described as maintaining the productive resources required for irrigation, so that future generations may have the same opportunity to use those resources as we do. Given the increasing importance of irrigated land for food production, the time has come when it is vital to intercept, reuse, and isolate drainage waters within the regions in which they are generated. Adoption of this strategy can be enhanced by policies that require farmers, and irrigation districts, to consider the off-farm impacts of irrigation and drainage. Such policies include linking water rights with salt rights to require the monitoring and management of both irrigation water and the salt loads in drainage waters. We review the knowledge gained since the early 1970s regarding the economic and agronomic aspects of irrigation and drainage, with a focus on drainage water reduction and sequential reuse of drainage water on salt-tolerant crops. Economic incentives that motivate farm-level and district-level improvements in water management are also reviewed. We conclude that adequate knowledge exists for implementing strategies that focus on water use and salt disposal within irrigated regions, and we recommend policies that will motivate improvements in productivity and enhance the likelihood of achieving sustainability. 相似文献
20.
为实现纵向岭谷区农业水管理调控,宏观上以流域水资源综合规划为基础,从需求入手,采取强化节水措施,提高水的利用效率,抑制需水的不合理增长,到2030年农田有效灌溉程度达到32%,灌溉水利用系数提高到0.581,农业灌溉需水总量控制在89.8亿m3,需水年均增长率仅0.52%,以MKIE BASIN模型的配置结果显示,各规划水平年能达到水资源供需平衡;微观上应建立数字流域工程,提高对流域雨水工情的实时监测.推行农业高效节水灌溉制度,建立和完善包括实时灌溉预报、渠系动态配水、实时信息采集和预报修正、灌区空间信息管理等内容的流域单元农业灌溉用水及水资源的实时调度系统,利用水资源配置成果与短期实时调度相结合,实现流域单元的农业高效用水调控. 相似文献