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131.
本文通过四川省射洪县的事例,分析了丘陵地区机械灌溉在发展农业和农村经济中的地位和作用,以及目前存在的困难和问题,提出了发展对策建议。 相似文献
132.
不同节水灌溉技术的节水机理试验研究 总被引:5,自引:1,他引:5
根据甘肃省特殊自然地理条件,对于喷灌、滴灌、渗灌及波涌灌几种方式下,小麦和玉米两种作物的灌溉节水机理进行了对比试验研究,分析了不同节水灌溉方式下这两种作物的节水性和生育动态。试验结果表明,在降雨、灌溉水量和前期土壤特性一定的情况下,在喷灌、滴灌、渗灌及波涌灌几种节水灌溉技术中,渗灌的节水性最好,依次为滴灌、喷灌、波涌灌。小麦和玉米在渗灌条件下产量比滴灌、喷灌和波涌灌都高,小麦渗灌产量比滴灌增加7.6%,比喷灌增加13.1%,比波涌灌增加22.4%。玉米渗灌产量比滴灌增加1.3%.比喷道增加6.3%。 相似文献
133.
R. Singh J.C. Refsgaard L. Yde G.H. Jørgensen M. Thorsen 《Irrigation and Drainage Systems》1997,11(3):185-213
A modelling system that combines the hydraulic simulations of the canal and hydrological simulations of the irrigated command is introduced. It uses MIKE 11 and MIKE SHE, two well-established modelling systems, for the hydraulic and hydrological simulations respectively. In addition, it also has an irrigation scheduling module and a crop growth module. The modelling system is applied to the Mahanadi Reservoir Irrigation Scheme, a large irrigation project in Central India. The results show that presently a significant amount of water is wasted in the command during the monsoon season. It is demonstrated that the minimization of this wastage could lead to a substantial crop production in the subsequent dry season. Furthermore, the simulations illustrate the versatility of the modelling system for planning and analysing the various aspects of an irrigation project. 相似文献
134.
湖南省节水灌溉分区与规划 总被引:1,自引:0,他引:1
将模糊聚类方法用于湖南省节水灌溉分区,建立了湖南省节水灌溉区划模型,将系统动力学的动态仿真原理用于节水灌溉发展规划,建立了节水灌溉发展规划的动态仿真模型。据此,提出了湖南省节水灌溉区划,并对各分区及全省“九五”期间节水浇灌发展作了详细规划。 相似文献
135.
W. G. M. Bastiaanssen T. Van der Wal T. N. M. Visser 《Irrigation and Drainage Systems》1996,10(1):1-23
The success of water management in large irrigation schemes with composites of soil, crop, wetness and micro-meteorological conditions is difficult to quantify. Performance assessment indicators, being among others a function of evaporation, are useful tools to evaluate the actual functioning of an irrigation system. The inevitable spatial variability of evaporation in large irrigation schemes makes its determination with conventional point measurements almost impossible. A new remote sensing evaporation parameterization algorithm has been tested with high resolution Landsat Thematic Mapper data for the Eastern Nile Delta, Egypt. Although the implementation of such an algorithm requires assumptions to be made, the current case study shows that these assumptions do not hamper the estimation of actual and potential evaporation at regional scale. The actual evaporation has been used to express the uniformity of crop water use which is related to the equity of irrigation water distribution. The coefficient of variance in actual evaporation between 53 differenent irrigation districts is 10% on average. The relative evaporation was considered to determine whether the crop was adequately irrigated. The relative evaporation was more than 75% for 48 out of 53 irrigation districts. It is concluded, that improved information on actual crop growth conditions through remote sensing provides an essential insight into the planning of real-time and seasonal irrigation water deliveries. 相似文献
136.
The logit technique is used to analyze the relationship between dichotomous reactions of satisfaction (satisfied/dissatisfied) with the irrigation system and certain independent variables. The result shows that five important variables — water availability on time, fertilizer availability, landholding size, farmers' participation in irrigation activities and location of farmland along the canal — significantly determine satisfaction. 相似文献
137.
138.
The Turkish program of irrigationmanagement transfer has gained worldwidecelebrity for its speed and effectiveness. This paper describes the program brieflyand assesses its effectiveness from anational perspective. The assessmentincludes changes in staffing levels,operational costs, service fee levels, andcost recovery from farmers. A companionpaper examines impacts at the local leveland looks specifically at changes in systemperformance. 相似文献
139.
The study reports farmers' attitudes andperceptions towards the ``barriers' and ``benefits' of automaticirrigation systems. Factor analysis was used to identify perceived ``barriers' and ``benefits' andthe impact of these on farmers' priority to adopt automation wasexamined. Results suggest that farmers'attitudes, particularly with respect to ``cost' and``lifestyle' influenced the priority given to adopting automaticirrigation systems. The area under pasturecultivation was also an importantdeterminant in the farmers' priority foradopting automatic irrigation systems. 相似文献
140.
由排灌机械行业的现状 ,结合江苏理工大学流体机械工程技术中心 15年来举办培训班的实践 ,提出了培养一大批掌握现代科学技术的工程技术人员和高素质员工是促进排灌事业发展最直接、最有效的措施 ,而制定和完善岗位培训制度是这一措施规范化、制度化、科学化的保证。文章阐述了岗位培训的概念 ,对建立岗位培训制度的原则、框架和体系作了探讨。 相似文献