参与式灌溉管理模式科层化问题分析

从管理模式的权限结构和交易成本视角出发,分析参与式灌溉管理模式科层化的内涵、成因及类别,探讨解决科层化问题的途径与方法。结果表明,理论上参与式灌溉管理模式在权限结构、决策方式和管理机制等方面表现为混合关系、共同决定和多种管理机制相融合的特点,但实践中却往往体现出等级制、层级决策、单一行政管理机制的科层化特征。基于节约交易成本的组织行为激励,政府凭借其权限控制权进行的选择性干预和农民用水户协会等组织的适应性反应是导致科层化问题的主要成因。将政府职责限定在公共服务范围内、完善法律体系支持成立非政府灌溉管理经营组织以及提高农民用水户协会等相关组织的自我管理能力是参与式灌溉管理模式得以可持续发展的关键所在。     

Irrigation management transfer in sub-Saharan Africa: an analysis of policy implementation across scales

ABSTRACT

This article explores how irrigation management transfer policies were implemented in Mali, Mozambique, Malawi and Zimbabwe. In Mali and Mozambique, where the irrigation bureaucracy controlled one large irrigation system, state agencies retained control over irrigation management despite reduced state funding. In Malawi and Zimbabwe, where the state irrigation systems and the irrigation bureaucracy were smaller, users have taken over irrigation management, but are having trouble sustaining irrigated agriculture. We show how irrigation management transfer policies were shaped by the interplay between international donors, macro-economic dynamics, national politics and the interactions with (and the nature of) irrigation infrastructure, bureaucracies and organized users.     

水利普查灌区专项中大型灌区普查中具体问题分析

某灌区是大连地区大型灌区之一,搞好该大型灌区的普查工作,对摸清地方水利基础资料,科学调度和利用本地区的水资源都具有重要的意义.文章充分列举了该大型灌区从数据采集到填报过程中出现的问题及处理方法.     

黄河下游引黄灌溉发展的战略转变及方向

本文对黄河下游现行的几种引黄灌溉模式进行了系统、全面的科学总结，首次提出了以当地水资源的合理开发利用为标准，将引黄灌溉模式概括为补源灌溉和非补源灌溉两大类，并对引黄补源灌溉的概念做了新的界定。这一新概念的提出，为今后黄河下游引黄灌溉的战略转变澄清了思想和理论上的障碍。明确提出黄河下游黄灌溉战略转变的方向是大力发展引黄补源灌溉，全面阐述了实行这种战略转变的客观必然性。     

Assessment of the contribution of irrigation to poverty reduction and sustainable livelihoods

Irrigation in developing countries tends to be stereotyped as equity reducing, in competition with other uses for scarce water resources, and often resulting in negative impacts for women and other disadvantaged groups. Agricultural intensification through the practice of irrigation as a strategy for poverty reduction is examined. There are four inter‐related mechanisms through which irrigated agriculture can reduce poverty. These are: improvements in the levels and security of productivity, employment and incomes for irrigating farm households and farm labour; the linkage and multiplier effects of agricultural intensification for the wider economy; provision of opportunities for diversification of rural livelihoods; and multiple uses of irrigation supply. There are also significant risks that badly designed and managed irrigation can negatively impact on poverty. It is concluded that irrigated farming varies widely in its form and impacts, and has diverse local attributes. Water resource management decisions must recognize this and be based on an holistic and livelihood‐centred assessment of irrigation benefits and costs that goes beyond food production objectives.     

智能化膜下滴灌条件下棉花灌溉制度试验研究

结合国家科技支撑课题"干旱区绿洲农业节水技术研究与示范--干旱区智能化微灌关键技术研究与示范",课题组在库尔勒包头湖农场棉花智能化滴灌试验田进行了为期3 a的大田试验,通过对试验资料的分析,初步掌握了智能化滴灌条件下棉花的耗水规律.通过耗水规律合理地修正了当地棉花的灌溉制度,既可以提高棉花产量又能够为棉花的灌溉决策提供...     

Appraisal and optimization of agricultural water use in large irrigation schemes: I. Theory

A new approach on the functioning of an irrigation scheme has been presented. A mathematical representation of the irrigation system based on measured system properties, such as losses due to percolation and to poor management, in only a part of the system is used. This mathematical representation is termed an equivalent irrigation network. The merit of this approach is that it reduces the number of required streamflow measurements.When water amounts are measured for a number of paths in the irrigation network, so-called path efficiencies are obtained. The path efficiency is a measure of the amount of water lost along the way. The numerical model that simulates the operation of the irrigation system is based on the path efficiencies. This simulation model in turn is used to calculate different objective functions, corresponding with different optimization goals, like uniform water distribution, minimum groundwater extraction, minimum cost of water supply.This paper gives the theoretical background of the approach. The application to an actual irrigation scheme will be discussed in a second paper.     

新疆奎屯河洪水特征和最大值研究

洪水极易造成各种灾害,对当地经济发展影响巨大。通过对奎屯河洪水特征分析研究,揭示奎屯河洪水和最大值规律,以便制定措施治害兴利,为防洪和工程管理及当地经济发展提供科学依据。     

Water Balance Study and Irrigation Strategies for Sustainable Management of a Tropical Ethiopian Lake: A Case Study of Lake Alemaya

Lake Alemaya in the Ethiopian Highlands has historically provided the surrounding area with water for domestic use, irrigation, and livestock and has served as a local fishery tank. Increasing irrigation and domestic water use, change in the local climate and changes in the surrounding land cover are believed to be the causes of Lake Alemaya’s demise. Expansion of major irrigated crops in particular chat (Catha Edulis), potato and vegetables and non-judicious use of irrigation water in the Lake Alemaya watershed led to presumption that irrigation is partly responsible for the withdrawal of large quantity of water from the lake. Thus, water balance study of Lake Alemaya was carried out under presumed scenarios in order to study the possible trends and fluctuations of the lake water level in response to proposed scenarios. Further, it is essential to study the irrigation performance for developing optimal irrigation schedules in the study area to make the best use of available water for long term sustainability of the water resources of Lake Alemaya. It was identified that expansion of the irrigated area in general and chat cultivation in particular in the study area have been the key to sustainable management of lake water, hence its expansion during the past 37 years (1965–2002) was studied through interpretation of satellite data. Subsequently, performance evaluation of the small-scale irrigation practices for major irrigated crops was carried out. Optimal irrigation schedules for different crop seasons were also developed for these irrigated crops using CROPWAT software. It was found that chat area increased from 190 ha in 1996 to nearly 330 ha in 2002. Further, it was observed that 43% surface area of the lake has reduced within a span of 37 years. Overall, maximum irrigation intensity of chat, potato and vegetables is observed during the first irrigation season of the crop calendar. Particularly, in case of chat, irrigation performance indicators such as Relative Water Supply (RWS), Relative Irrigation Supply (RIS), Depleted Fraction (DF) and Overall Consumed Ratio (OCR) values indicated poor performance of irrigation practices. From the analysis, it was found that the application of a fixed irrigation depth and fixed irrigation interval combinations of (25 mm—25 day), (20 mm—20 day), or (20 mm—25 day) are recommended for chat in the study area. Optimal irrigation schedules were decided on the basis of combination of irrigation interval and depth that results in low loss of irrigation water with reasonable yield reduction. Thus, determination of appropriate water management strategy can ensure proper utilization of the available water resources and improve the water application efficiency of the small-scale irrigation practices around Lake Alemaya, Ethiopia.     

Is It Possible to Shift to Hydrological Boundaries? The Ferghana Valley Meshed System

The management of water resources according to hydrological boundaries at different implementation levels (river basin, irrigation system, or water user association) is promoted internationally. This approach to water management, especially for the basin, is starting to be challenged from different perspectives: representation within basins, appropriateness for basins in the south, and the challenges of merging boundaries for surface and groundwater sources. It has been challenged only recently in relation to its appropriateness for indigenously constructed (informal) irrigation systems. To these critiques, this paper adds the historical development and originally intended purpose of engineered irrigation systems and therefore calls into question whether it is always possible to introduce hydrological boundary management in the formal systems in Central Asia.     

冬小麦垄膜沟灌高效节水灌溉试验研究

本文以四个站年垄膜沟灌试验资料为依据 ,以单方水产值最大为目标 ,分析提出了各站试验年气候条件下的冬小麦垄膜沟灌节水高效灌溉制度 ,并与相应灌水条件下的畦灌灌溉制度进行了比较。结果表明 ,垄膜沟灌较畦灌可平均节约灌溉水量 2 9.7% ,平均增产 6 33kg/hm2 ;单方水产量平均增产 0 .44kg ,单方水产值平均增加 0 .5 3元 ,纯收入平均增加 5 30元 /hm2 。     

内蒙古引黄灌区适宜秋浇定额研究

秋浇是内蒙古引黄灌区一种传统的洗盐压碱灌溉制度,秋浇用水量是灌区一年中灌水量最大的一次。以典型试验资料为依据,通过对不同秋浇定额灌溉条件下春播前土壤水盐条件、土壤的脱盐效果和增水效果的对比分析,研究提出内蒙古引黄灌区基于节水的适宜秋浇定额为1 500 m3/hm2。     

基于光学和雷达遥感信息的灌溉信号分析及灌溉面积提取方法研究-以华北平原灵寿县磁右灌区为例

目前,灌溉面积主要通过调查统计方式获取,时效性和准确性较差,而在灌区用水管理中迫切需要掌握实际灌溉面积及其空间分布和动态变化等信息。为此,本文开展基于雷达遥感信息的灌溉信号探测识别及次灌面积提取方法研究。首先,使用水云模型结合实测土壤水分数据进行模拟,量化灌溉事件导致后向散射系数的变化。然后,提出一种基于时序差值和局部阈值法的实际灌溉面积提取方法,使用高频次的哨兵1号雷达卫星遥感数据开展华北平原灵寿县磁右灌区灌溉面积提取,并结合灌区实地调查资料对提取结果进行验证。结果表明:使用水云模型模拟显示春季小麦地块的灌溉事件可导致C波段的雷达后向散射系数变化超过1 dB,灌溉信号可被绝对辐射精度优于1 dB的雷达卫星探测;基于时序雷达后向散射系数分析显示,灌溉事件导致C波段雷达后向散射系数呈现明显的先增大后减小的时域特征,与降水事件不同,灌溉事件导致雷达后向散射系数呈现明显的局地变化特征。以本文提出的方法提取研究区的灌溉面积,结合实地调查样本检验,结果表明灌溉面积的总体提取精度为76.6%。小麦返青期第一次渠灌面积约为9.20万亩,小麦拔节期第二次渠灌面积约为10.64万亩。此外,由于井灌区和渠灌区存在明显的时差,基于雷达遥感信息可对不同水源的灌溉区进行探测,研究区井灌面积约为3.9万亩。基于高频次的雷达遥感信息可对灌区的灌溉事件进行探测,本文提出的方法可为区域次灌溉面积调查和流域水资源管理等应用提供技术支撑。     

凤台县农田灌溉水有效利用系数变化影响因素分析

为提高农田灌溉水有效利用系数,以凤台县实测调查资料为基础,结合当地生产实际,运用首尾测算分析法测算了凤台县2018—2021年农田灌溉水有效利用系数,从水资源条件、灌区总体规模、工程投入和管理措施四个方面对农田灌溉水有效利用系数的影响及变化规律进行了探讨分析。结果表明,持续推进灌区续建配套与节水改造项目、推广节水灌溉技术和加强灌区管理能有效提高凤台县灌溉水利用系数。研究成果对发展节水型灌区、节水型社会具有十分重要的意义,对制定县域节水灌溉规划具有一定参考价值。     

发展高效节水灌溉之哲学思考

灌溉的物质条件决定了灌溉方式这个意识选择;灌溉发展具有规律性,但任何一种灌溉方式都有其适用范围,都与周围各种条件和现实相联系,只有不断创造条件,才能有效推进高效节水灌溉发展;只有从失败中学习并依靠新的认识指导新的实践,才能循环往复推进灌溉事业的进步和提升.因此,应在实践中充分认识发展高效节水灌溉的艰巨性和曲折上升性,增强发展高效节水灌溉的自党性、支撑力和自信心,积极创造条件,因地制宜加快推进高效节水灌溉的健康发展.     

21世纪初期中国灌溉发展战略

从宏观经济的观点出发,分析了21世纪初中国农业和国民经济发展的新形势及其对灌溉发展的需求;从社会经济可持续发展和水资源可持续利用的观点出发,提出了符合中国社会经济发展阶段和水平要求的灌溉发展新思路和战略.对全国不同的地区,考虑水资源和环境条件,提出了具体的灌溉发展方向.最后提出了主要的灌溉发展战略措施:发展节水灌溉,实施南方管道化灌溉排水,推广集中供水、分散蓄水,扩大补水灌溉面积,地表水与地下水联合运用,结合当地水土资源条件发展灌溉.     

泾惠渠灌区干旱时段内的地下水动态

泾惠渠灌区是陕西重要的农业生产基地,研究灌区干旱时段的地下水动态对灌区农业生产具有重要意义。通过灌区多年的降水量资料,采用Z指数法选取了灌区的典型干旱时段,然后选取灌区内的典型观测井位分析了其干旱时段内地下水动态特征。     

微灌管道局部水头损失扩大系数的修正

根据微灌水力学原理,修正了微灌管道局部水头损失扩大系数,并对影响局部水头损失扩大系数的因素进行了敏感性分析。结果表明:当微灌管道出水口较少及进口端长度不等于出水口间距时,采用修正后的微灌管道局部水头损失扩大系数可以提高管道总水头损失的计算精度。     

山东栖霞果园灌溉工程管理模式及发展问题探讨

山东省栖霞市是全国重要苹果产区,果园节水灌溉工程是维护果林经济发展和果品质量的重要基础设施,其建设管理受到当地政府和果农重视。通过研究近年山东栖霞果园灌溉工程管理模式及发展进程,分析各类模式的优、缺点及存在的问题,提出了相应的意见和建议,希望政府加大政策扶持力度,使农田水利工程既能建好,又能长久发挥效益。     

基于多源遥感数据和水量平衡原理的灌溉用水量分析

农业灌溉水量估算和区域农业用水的校核是用水统计、监管的难点。现行基于典型调查和定额推算的方法依赖统计人员经验,易受人为因素干扰,准确性难以控制;采用基于水量平衡的灌溉用水推算方法时,区域蓄水变量和耗水量等要素仅依靠传统地面监测条件难以获取。遥感技术能够解决水量平衡方程中区域蓄水变量和蒸散发的估算问题,可以提高水量平衡方法在计算灌溉用水中应用的可行性,但大多数遥感产品存在区域适用性和精度的问题,需要将多种产品结合,通过相互校验和组合控制误差;此外,遥感产品与水量平衡要素之间还存在一定程度的概念差异,需要进行匹配与转换。本文构建了一种基于多源遥感数据和水量平衡原理的灌溉用水分析方法,利用区域水量平衡方程检验多源遥感数据的一致性和可靠性,建立遥感数据与水量平衡要素的对应关系,选取合理的区域蒸散发数据,再利用田间水量平衡将总蒸散发分解为降水蒸散发和灌溉蒸散发,推算得到灌溉耗水量和灌溉用水量的合理范围。应用本文提出的方法进行山东省济南市2012—2015年灌溉用水分析,并与济南市水资源公报统计的农业用水进行对比,结果表明:在降水量接近多年平均的2012、2013、2015年,二者结果较为接近;在干旱的2014年,本文的分析结果与公报结果相差较大。结合同期农田作物长势、区域地下水位变化分析,认为该年份存在较大的灌溉用水,本文结果比较合理。本文方法可为校核区域灌溉用水统计数据的合理性提供技术支撑。