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1.
This paper focuses on irrigation schemes under rotational water supply in arid and semiarid regions. It presents a methodology
for developing plans for optimum allocation of land area and water, considering performance measures such as productivity,
equity and adequacy. These irrigation schemes are characterized by limited water supply and heterogeneity in soils, crops,
climate and water distribution network, etc. The methodology proposed in this paper, therefore, uses a previously developed
simulation–optimization model (Area and Water Allocation Model, AWAM) that considers the heterogeneity of the irrigation scheme
in the allocation process, and modifies this to take account of equity and adequacy of supply to irrigated areas. The AWAM
model has four phases to be executed separately for each set of irrigation interval over the irrigation season: 1. generation
of irrigation strategies for each crop–soil–region combination (CSR unit), 2. preparation of irrigation programmes for each
irrigation strategy, 3. selection of specified number of irrigation programmes for each CSR unit and 4. optimum allocation
of land area and water to different parts of the irrigation scheme (allocation units) for maximizing productivity. In the
modified AWAM model, the adequacy is included at Phase-2 (by including only the irrigation programmes for full irrigation
of each CSR unit) and equity is included at Phase-4 (by including the constraints for equity). The paper briefly discusses
the applicability of the modified AWAM model for a case study of Nazare medium irrigation scheme in Southern India. The results
of the case study indicated that the performance measures of productivity, equity and adequacy conflict with each other. 相似文献
2.
The non-uniformity of soils, weather, fields, cropping pattern and canal systems in most surface irrigation schemes makes irrigation water management complex, but optimum performance is important particularly in irrigation schemes with limited water supply. This paper focuses on the performance of irrigation water management during the area and water allocation with a case study of an irrigation scheme in the semi-arid region of India. Often the irrigation managers or authorities of these heterogeneous irrigation schemes also need to deal with different allocation rules. The allocation plans and the corresponding water delivery schedules during the allocation process were estimated with the help of a simulation–optimisation model for different allocation rules based on cropping distributions (free and fixed), water distributions (free and fixed-area proportionate), irrigation depth (full, fixed depth and variable depth irrigation) and irrigation interval (from 14 to 35 days). The performance measures of productivity (in terms of net benefits and area irrigated), equity (in water distribution), adequacy and excess were assessed for these different allocation plans and schedules. These were further compared with the performance measures of the existing rule (fixed depth irrigation at a fixed interval). The analysis revealed that these performance measures are in some cases complimentary and in other cases conflicting with each other. Therefore, it would be appropriate for the irrigation managers to understand fully the nature of the variation in performance measures for different allocation rules prior to deciding the allocation plans for the irrigation scheme. 相似文献
3.
Shigeya Maeda Tatsuya Nagamochi Toshihiko Kawachi Junichiro Takeuchi 《Irrigation and Drainage Systems》2011,25(2):81-96
A multiobjective optimization model has been presented for allocating irrigation waters in a rice paddy area. Water-saving
practices conducted on the field-plot basis are considered and expressed in the optimal water allocation problem in the regional
scale. Irrigation water allocated to the blocks of paddy fields is divided into two components of a basic amount and a safety
margin in order to mitigate the effect of hydrological and hydraulic uncertainties on the study area. Four competing management
objectives with regard to total rice yield, total water-saving cost, equity of water allocation, and safety of water supply
are defined in the linear programming formulation so that noninferior solutions can be procured which are informative and
persuasive in decision-making. Applicability of the optimization model is examined using water allocation problems for a hypothetical
irrigation system. It is demonstrated that the optimization model can provide satisficing solutions where the four objectives
are harmonized under substantial variations of total water supply to the irrigation system. 相似文献
4.
宁夏引黄灌区历史悠久,是我国大型灌区之一。自实施宁夏引黄灌区续建配套与节水改造项目以来,灌区骨干工程安全状况有了较大改善,渠道综合调控能力不断增强,灌区节水意识进一步提高。良田渠灌域是青铜峡河西灌区的组成部分,通过渠道砌护及建筑物新建、维修等改造工程措施,提高灌溉水利用系数,减少引黄水量,完善渠道防洪体系,为渠道提供安全的行水条件。对灌区经济持续发展和工程效益的充分发挥起到推动作用,同时对改善渠道沿线生态环境和城市美化也具有积极意义。 相似文献
5.
侯景伟 《中国农村水利水电》2014,(3):166-168
为了解决灌区水资源配置中的信息采集方法落后和多目标模型求解易陷入局部最优等问题,通过伪随机并行搜索和最近邻域选择等策略对Pareto蚁群算法进行改进,然后将Pareto蚁群算法与3S技术耦合,以宁夏银北灌区为仿真对象,利用改进的Pareto蚁群算法计算灌区多目标、多约束的水资源空间优化配置模型,获得最优的井灌水量、渠灌水量、排水量以及最优的经济效益和灌排费用。基于Pareto蚁群算法和３S技术的灌区水资源空间优化配置,能加快算法的收敛速度,获得全局最优解,使优化结果更接近实际,对灌区的水资源宏观调度具有一定的参考价值。 相似文献
6.
明确初始水权数量与质量的分配系 总被引：1，自引：0，他引：1
为解决水资源管理和水市场建设中涉及的水权问题，本文以内陆黑河干流为背景建立了干旱区水权分配系统。按照不同地区使用的水资源除了具有相对公平的数量，还应该具有相对公平的质量的原则，系统将以往模糊的流域水权界定对象清晰化，明确其为河流在某种社会经济条件下，为满足生态和水环境的要求，流域所能调配的水资源。为此，系统考虑与地区取水相关的经济和环境因素，运用基于水资源模型和区域水质模型的多目标规划方法计算流域各地区理论取水量，并将理论取水量结果用于改进目前的水权分配计算方法，不仅给出了流域各地区的水权分配比例，同时将各地区按水权分配到的水资源数量和质量也一并给出。实际应用证明了系统的有效性，给出的水权分配结果较以往类似成果加深了各地区对自身拥有的水资源状况、以及将面临的流域整体水资源形势的认识。 相似文献
7.
H. K. Barth 《Agricultural Water Management》1999,40(2-3):283-290
Since scarcity of water is a major problem in semi-arid and arid areas of Spain and many other Mediterranean regions, water consumption in irrigated agriculture has to be reduced to a sustainable level that is also adapted to the environment. This goal can be reached by applying the highly effective and resource preserving techniques of micro-irrigation. In order to improve these techniques, a new subsurface irrigation system was developed by modification of conventional subsurface systems through the following innovative elements:
a new design of the lateral hoses which prevents the penetration of roots into the external water outlets and the block up by soil particles;
an impermeable polyethylene foil placed below the lateral pipes to prevent water loss through deep percolation, especially in sandy substrates;
a special installation equipment consisting of a V-shaped device which releases foil and pipe simultaneously into the soil without disturbing the natural soil profile.
After the experience of several years of operation, these elements have proved to be highly effective. Compared to other irrigation methods, the high irrigation efficiency achieved by this system was outstanding. Minimum maintenance requirement and a long life span are additional positive characteristics of the system. The beneficial outcomes of this system give reason for an optimistic appraisal of the strategies involved towards sustainable irrigated agriculture. 相似文献
8.
《Agricultural Water Management》2006,83(3):243-251
Irrigation schemes have contributed to the availability of water not only for agriculture but also for domestic use by rural households. In the Uda Walawe irrigation scheme in southern Sri Lanka, irrigation canals are being lined with concrete to save water, meant to enable extension of the irrigated area. The effects of lining on the availability of water for multiple uses were investigated by field measurements of water levels and by an inventory of the perceptions of changed water availability by the population through focus group discussions. From the measurements it was determined that canal seepage provides an important contribution to groundwater recharge. It was estimated that after concrete lining the annual groundwater recharge in the irrigated areas will be reduced by approximately 50%. This saves a substantial amount of water that can be used to extend the irrigation area so more people can benefit from the available irrigation water. However, in the currently irrigated areas lining will have negative impacts by lowering groundwater levels due to a reduction in seepage from canals. This seepage contributes to the recharge of shallow wells used by the population to obtain water for drinking and cooking. The perception of the population was that enough water remains for domestic use. Other changes, such as reduced yields from home gardens were considered to be more important. Despite these negative impacts the expected positive impacts in the extension area justify, from a social equity point of view, concrete lining as a measure to redistribute the available water over the Uda Walawe area. 相似文献
9.
灌区是我国粮食安全和现代农业发展的基础保障,同时也是区域经济发展和生态环境保护的重要基石。然而西北地区独特的气候、地貌及社会经济状况导致了灌区生产能力和生态服务功能难以满足现代生态农业发展的需求。通过系统分析西北灌溉农业发展中面临的水资源过度开发、土壤盐碱化严重、生态环境功能低下等方面的问题,阐述了西北现代生态灌区的内涵与特征,并基于农业生产“功能水分”来源,将西北灌区划分成了灌溉依赖型灌区、灌溉主导型灌区、灌溉补充型灌区和灌溉提质型灌区4类。以灌区农业生产系统、物能输配系统、生态环境系统为建设对象,提出了灌区生态服务功能优化配置、灌区农田物能调控和灌区生态系统安全评估三大核心理论,构建了灌区系统控污与景观价值提升技术、灌排系统管控技术、作物生境要素综合调控技术三大关键技术,从而形成了西北现代生态灌区理论与技术保障体系,为我国西北灌溉农业高质量可持续发展提供理论与技术指导。 相似文献
10.
This study analyzes the effects of irrigation modernization on water conservation, using the Riegos del Alto Aragón (RAA) irrigation project (NE Spain, 123354 ha) as a case study. A conceptual approach, based on water accounting and water productivity, has been used. Traditional surface irrigation systems and modern sprinkler systems currently occupy 73% and 27% of the irrigated area, respectively. Virtually all the irrigated area is devoted to field crops. Nowadays, farmers are investing on irrigation modernization by switching from surface to sprinkler irrigation because of the lack of labour and the reduction of net incomes as a consequence of reduction in European subsidies, among other factors. At the RAA project, modern sprinkler systems present higher crop yields and more intense cropping patterns than traditional surface irrigation systems. Crop evapotranspiration and non-beneficial evapotranspiration (mainly wind drift and evaporation loses, WDEL) per unit area are higher in sprinkler irrigated than in surface irrigated areas. Our results indicate that irrigation modernization will increase water depletion and water use. Farmers will achieve higher productivity and better working conditions. Likewise, the expected decreases in RAA irrigation return flows will lead to improvements in the quality of the receiving water bodies. However, water productivity computed over water depletion will not vary with irrigation modernization due to the typical linear relationship between yield and evapotranspiration and to the effect of WDEL on the regional water balance. Future variations in crop and energy prices might change the conclusions on economic productivity. 相似文献
11.
Deficit irrigation has been suggested as a way to increase system benefits, at the cost of individual benefits, by decreasing the crop water allocation and increasing the total irrigated land. Deterministic methods are common for determining optimal irrigation schedules with deficit irrigation because considering the inherent uncertainty in crop water demands while including the lower and upper bounds on soil moisture availability is a hard problem. To deal with this, a constraint state formulation for stochastic control of the weekly deficit irrigation strategy is proposed. This stochastic formulation is based on the first and second moment analysis of the stochastic soil moisture state variable, considering soil moisture as bounded between a maximum value and a minimum value. As a result, an optimal deficit irrigation scheduling is determined using this explicit stochastic model that does not require discretization of system variables. According to the results, if irrigation strategy is based on deterministic predictions, achievement of high, long-term expected relative net benefits by decreased crop water allocation and increased irrigated land may have a higher failure probability. 相似文献
12.
王凤娇 《国际沙棘研究与开发》2016,(4):32-34
灌区是农业发展的骨干,灌区耕地成为灌区内农村居民的衣食之源,其在我国农业产业化以及农村经济发展领域,一直具有不可或缺的功用,尤其是在改善区域内生态环境、水土保持等层面,地位极为重要.本文对月亮泡东灌区节水改造技术加以探究,在阐述灌区改造意义的基础上,重点介绍这一时期月亮泡东灌区节水改造形式,提出一种新型发展方向,即引入现代高新技术、绿色环保、高效低耗、环境友好型的灌区改造发展路径,包括灌区渠道的防渗节水设计、区域内管道输水灌溉设计,以及喷灌技术的应用等. 相似文献
13.
Building a climate resilient farm: A risk based approach for understanding water, energy and emissions in irrigated agriculture 总被引：1，自引：0，他引：1
The links between water application, energy consumption and emissions are complex in irrigated agriculture. There is a need to ensure that water and energy use is closely considered in future industry planning and development to provide practical options for adaptation and to build resilience at the farm level. There is currently limited data available regarding the uncertainty and sensitivity associated with water application and energy consumption in irrigated crop production in Australia. This paper examines water application and energy consumption relationships for different irrigation systems, and the ways in which the uncertainty of different parameters impacts on these relationships and associated emissions for actual farms. This analysis was undertaken by examining the current water and energy patterns of crop production at actual farms in two irrigated areas of Australia (one using surface water and the other groundwater), and then modelling the risk/uncertainty and sensitivity associated with the link between water and energy consumption at the farm scale. Results showed that conversions from gravity to pressurised irrigation methods reduced water application, but there was a simultaneous increase in energy consumption in surface irrigation areas. In groundwater irrigated areas, the opposite is true; the use of pressurised irrigation methods can reduce water application and energy consumption by enhancing water use efficiency. Risk and uncertainty analysis quantified the range of water and energy use that might be expected for a given irrigation method for each farm. Sensitivity analysis revealed the contribution of climatic (evapotranspiration and rainfall) and technical factors (irrigation system efficiency, pump efficiency, suction and discharge head) impacting the uncertainty and the model output and water-energy system performance in general. Flood irrigation systems were generally associated with greater uncertainty than pressurised systems. To enhance resilience at the farm level, the optimum situation envisaged an irrigation system that minimises water and energy consumption and greenhouse gas emissions. Where surface water is used, well designed and managed flood irrigation systems will minimise the operating energy and carbon equivalent emissions. Where groundwater is the dominant use, the optimum system is a well designed and managed pressurised system operating at the lowest discharge pressure possible that will still allow for efficient irrigation. The findings might be useful for farm level risk mitigation strategies in surface and groundwater systems, and for aiding adaptation to climate change. 相似文献
14.
《Agricultural Water Management》1996,30(2):201-216
In a companion paper, the development of a water balance model to predict the changes in water balance components in relation to field layout in lowland paddy fields was outlined. In this study, the model was applied to a large irrigated area to assess and compare the water balance of intensive and extensive field layouts. The results show significant differences in water balance which are attributed to the layouts and water management practices. The field layouts influenced the equity of water allocation, effective rainfall, water use efficiencies and relative proportion of various water balance components. Eight indices are computed to evaluate the effects of layout under different land and hydrological conditions. Appropriate measurement scales for ranking the indices are proposed. 相似文献
15.
In many countries, irrigation water is usedfor several purposes other than irrigatingfield crops. In Sri Lanka, irrigationwater from canals, wells, and reservoirs isused for domestic purposes, industry,livestock, and fisheries, and it alsocontributes to sustain the environment. However, policy makers and water managersin irrigation systems only take intoaccount water used for irrigating the fieldcrops and sometimes water used for domesticpurposes. Owing to the failure torecognize the different uses and users ofwater, the water in irrigation systems hasbeen undervalued. This paper presents theenvironmental impact of irrigation and aframework for valuing water for itsmultiple and often competing uses,especially focusing on water uses forecological services, in this case wetlands.The south coastal area of Sri Lanka wasselected as a site for a case study, including2,610 ha of irrigated area and adownstream wetland area of 2,250 ha whichhas five lagoons. This wetland areacombines coastal, marine and freshwaterecosystems in a tropical environment inwhich distinct plant and animal speciescoexist in a delicate balance. All users ofwater and other resources, and theirenvironmental problems were identified. Thispaper discusses the policy and managementimplications of valuing water for competinguses. 相似文献
16.
基于DP-PSO算法的灌区农业水资源优化配置 总被引：2，自引：0，他引：2
针对引水灌区,考虑灌溉用水总量约束和时段可供水量约束,以单一作物非充分灌溉下灌溉制度优化为第一层,区域多种作物种植结构及水量分配为第二层,分别采用动态规划和粒子群算法求解,建立了基于DP-PSO算法的灌区农业水资源优化配置模型。针对多重约束问题,提出了一种初始化粒子群的方法,并通过粒子速度的动态变化来保证每代粒子都满足约束,提高了算法的收敛速度和收敛精度。以赣抚平原灌区为对象,考虑降雨和水源可供水量不同步的特点,计算了3种降雨频率、多年可供水条件下的农业水资源优化配置方案。结果表明,基于DPPSO算法的农业水资源优化配置模型合理可靠,为引水灌区农业水资源优化提供了一种新的方法。 相似文献
17.
Waterlogging and salinization are major impediment to the sustainability of irrigated lands and livelihoods of the farmers, especially the smallholders, in the affected areas of the Indus Basin. These problems are the result of a multitude of factors, including seepage from unlined earthen canals system, inadequate provision of surface and subsurface drainage, poor water management practices, insufficient water supplies and use of poor quality groundwater for irrigation. About 6.3 million ha are affected by different levels and types of salinity, out of which nearly half are under irrigated agriculture. Since the early 1960s, several efforts have been made to improve the management of salt-affected and waterlogged soils. These include lowering groundwater levels through deep tubewells, leaching of salts by excess irrigation, application of chemical amendments (e.g. gypsum, acids, organic matter), and the use of biological and physical methods. However, in spite of huge investments, the results have in general been disappointing and the problems of waterlogging and salinity persist.This paper reviews sources, causes and extent of salinity and waterlogging problems in the Indus Basin. Measures taken to overcome these problems over the last four decades are also discussed. The results reveal that the installed drainage systems were initially successful in lowering groundwater table and reducing salinity in affected areas. However, poor operation and maintenance of these systems and provision of inadequate facilities for the disposal of saline drainage effluent resulted in limited overall success. The paper suggests that to ensure the sustainability of irrigated agriculture in the Indus Basin, technical and financial support is needed and enhanced institutional arrangements including coordination among different federal and provincial government agencies to resolve inter-provincial water allocation and water related issues is required. 相似文献
18.
滴灌控制面积对滴灌系统的投资成本和运行费用有明显的决定作用，是滴灌系统设计中必须考虑的问题。本文根据滴灌系统设计理论分析了滴灌控制面积对首部工作流量、工作压力、运行电费和对田间轮灌管理及农田灌溉安全的影响。结果表明，随着滴灌控制面积的扩大，首部工作流量和压力提高，导致运行电费增大；而且引起田间轮灌时间紧张，管理困难；同时还使灌溉安全性降低。 相似文献
19.
Based on a simulation model reflecting physical and economic conditions typically found in rice irrigation systems in Asia, the irrigation performance implications of alternative water distribution rules for dry season irrigation are evaluated under varying degrees of water shortage. The rules examined reflect differing water distribution strategies designed either to maximize conveyance efficiency, economic efficiency, or equity; or to achieve a balance between efficiency and equity objectives. Irrigation performance is evaluated using several efficiency measures reflecting the physical, agronomic and economic productivity of water, and one measure of equity. Economic efficiency and equity among farmers within the portion of the irrigation system that is on in any given season are shown to be complementary, and not competing objectives. Economic efficiency and equity among all farmers within the command area of the irrigation system are largely complementary strategies at the lower levels of water shortage, but with increasing shortage, significant tradeoffs develop between these objectives. An operational rule for water distribution under a goal of maximizing economic efficiency is developed, and the data requirements for its implementation are shown to be modest. Under the model's assumed conditions of dry season rice production dependent solely on surface irrigation for water, the distribution strategy designed to maximize conveyance efficiency results in only modestly lower levels of economic efficiency and equity than could be achieved by the strategy designed to maximize economic efficiency. 相似文献
20.
土地和水资源是一个国家进行农业发展的基础投入,马铃薯滴灌栽培可以解决水资源和耕地短缺问题。该研究评估了不同滴灌频率相比于常规沟灌对作物生长、产量和水分利用效率的变化。试验结果表明,隔天滴灌要比每3、4和5 d进行滴灌增效更为显著。通过采用隔天滴灌单位供水面积上最高水分利用效率（56.24 kg（hm2·mm））和2.23的最高成本效益比（B∶C）,之后每3 d进行1次滴管的B∶C为2.25,而传统沟灌水分利用效率为14.16 kg（hm2·mm）、B∶C比值是1.91。该研究结果表明,对于像马铃薯这种高水分敏感作物来说,滴灌作为一种经济的用水方式在水分管理中起着重要作用。因此,采用节水的滴灌系统有利于增加马铃薯栽培面积。 相似文献