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1.
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   

2.
Data on flows in irrigation and drainage canals and data on climate, crops, and cropped areas are essential for the management of irrigation systems. Only part of these data can be collected with satellite remote sensing (SRS). This paper discusses the possibilities for the practical use of SRS data in the management of irrigation systems. Satellite remote sensing images are more useful for intra- and inter-seasonal monitoring, with a time horizon of months or years, than for use in day-to-day management of irrigation schemes: either the operation of the system cannot be changed quickly, or the operation would require a more frequent input of SRS data than is at present feasible.  相似文献   

3.
一种新型的节水灌溉技术——渗灌   总被引:19,自引:3,他引:19  
渗灌技术具有显著的节水、节能、省工、增产和提高品品质的特点,是发展我国节水型农业的重要技术措施之一,本文较详细地介绍了渗灌系统的田间规划,设计参数选择及生物堵塞的预防和处理办法,建议引进利用废旧轮胎回收的橡胶生产渗灌管的专利技术和关键生产设备,实现渗灌管的国产化。  相似文献   

4.
In this paper, a contribution to the design of collective pressurised irrigation networks in solid-set sprinkler-irrigated windy areas is presented. The methodology is based on guaranteeing minimum on-farm performance, using a historical hourly wind speed database and a ballistic solid-set irrigation simulation model. The proposed method was applied to the Montesnegros Irrigation District (central Ebro basin, Spain). The district irrigates an area of 3493 ha using an on-demand schedule. The average wind speed in the area is 2.8 m s−1. An analysis of district water records showed that farmers often reduce water demand when the wind speed is high, but their irrigation decision making is limited by the capacity of the irrigation network and by the unpredictable character of local winds. Simulations were performed for 11 irrigation seasons, 2 triangular sprinkler spacings (18 m × 18 m and 18 m × 15 m), and 2 sprinkler models. The percentage of monthly suitable time for irrigation was determined for four management strategies. The first one was based on a wind speed threshold (3 m s−1), while the other three were based on three levels (standard, relaxed and restrictive) of two irrigation performance parameters: the Christiansen Uniformity Coefficient (CU) and the Wind Drift and Evaporation Losses (WDEL). The standard strategy classified the time as suitable for irrigation when CU ≥ 84% and WDEL ≤ 20%. The thresholds limits of the irrigation parameters for the relaxed strategy were CU ≥ 80% and WDEL ≤ 25%. Finally, the restrictive strategy used thresholds of CU ≥ 90% and WDEL ≤ 15%. The suitable time for the first strategy (56%) was always lower than for the standard and the relaxed strategies (with respective average values of 75 and 86%), and higher than for the restrictive strategy (30%). In order to design the collective network, the hydrant operating time was equalled to the suitable time for irrigation. The differences in the cost of the collective network plus the on-farm equipment were particularly relevant between the restrictive strategy and the other three. Differences in suitable operating time were clear between sprinkler spacings, and less evident between sprinkler models. The application of the proposed methodology may be limited by the availability of historical wind speed records and CU estimates for different combinations of sprinkler models, sprinkler spacings and wind speed.  相似文献   

5.
变量技术在精准灌溉上的应用   总被引:4,自引:0,他引:4  
本文通过对精准灌溉系统基本概念的论述,提出变量技术是精准灌溉的技术关键。阐述了变量技术与设备在圆形和平移式喷灌机上的应用,并指出在应用中应注意的问题。  相似文献   

6.
涌泉根灌技术研究与应用   总被引:6,自引:0,他引:6  
吴普特  朱德兰  汪有科 《排灌机械》2010,28(4):354-357,368
提出了一种新型涌泉根灌灌水方法,研究设计了一种灌水器,实现了直接将灌溉水输送到植物根系部位的研究目标,研制的涌泉根灌灌水器流态指数小于0.5,属紊流范畴.为了测得不同节水灌溉方式的应用效果,在陕北山地5年生枣树实施了管灌、滴灌和涌泉根灌等工程38.67hm^2,对3种不同灌水方法的经济效益作了分析.结果表明,与不灌溉相比,管灌、滴灌和涌泉根灌的净增收入分别为4707.70,8446.00和10926.00元/hm^2;管灌、滴灌和涌泉根灌每方灌溉水产值分别为1.90,11.30和14.60元/m3.涌泉根灌与滴灌相比,年成本降低2030元/hm^2,净收入增加2480元/hm^2,每方灌溉水产值提高3.30元/m3;涌泉根灌与管灌相比,年成本降低743.30元/hm^2,净收入增加6218.30元/hm^2,每方灌溉水产值提高12.70元/m3.不同节水灌溉方式均使得枣园净收入大幅度提高,尤其是涌泉根灌方式,净增值率高达235.0%.建议在山地经济林果中大面积推广应用涌泉根灌技术.  相似文献   

7.
刘星星 《湖南农机》2013,(6):188-189
滴灌是农业灌溉技术的一项革命性变革。这种灌溉方式,对节省灌溉用水、实现高产、控制杂草等有它独到之处。本文对滴灌进行了简述并分析了滴灌技术在我国节水灌溉中的应用,对其优势、节水效果等方面的进行了分析探讨,为我国节水灌溉的发展提供借鉴。  相似文献   

8.
基于水利统计数据,分析了近10 a中国节水灌溉应用分布,发现东北以喷灌为主,西北以微灌为主,华北以低压管灌为主,华东以渠道灌溉为主,具有明显的区域特征,节水灌溉仍有50%发展空间,喷灌技术占比与欧美国家相比仍然偏低.总结回顾了中国喷灌机发展历程、研究进展和发展趋势.从国家政策引导、智慧农业发展、农业种植结构变化和盐碱地耕地改造4个方面,分析了在资源环境约束挑战下中国喷灌机的发展机遇.阐明了喷灌的优势和不可替代作用,指出随着中国高标准农田建设及农业规模化经营稳步推进,喷灌机性能及功能不断增强,使以往喷灌的局限性逐步转变成发展优势.最后从补齐农业全程机械化短板、水肥药一体化作业新模式和无人化智能化方面展望了中国喷灌机未来发展前景.  相似文献   

9.
解决干旱、半干旱山地的农用灌溉用水问题,是帮助干旱山区农民脱贫致富的关键。采用YD型移动式高扬程灌溉及SYD型移动式滴灌技术,具有投资少、转移快捷方便、灌溉效率高及增产增效等优势,通过典型干旱山区的应用研究,该灌溉技术具有推广使用价值。  相似文献   

10.
认养农业是共享经济的具体体现之一,依托于互联网、政府以及自身服务三者的有机结合。新疆乌鲁木齐市认养农业起步较晚,目前认养农业范围已扩展至果蔬、禽畜、植被等多种农业生产领域。耕读园自2020年运用于经营体制中,在自然环境、消费群体、消费观念等区位优势的加持下,相较于以往认养模式,其新颖生产方式和多样化娱乐项目备受消费者青睐。在消费者与经营者的共同经营下,实现耕读园员工增收、农业可持续发展。在发展过程中,易受消费者的认知、多样化需求、操作程序等因素影响,致使其存在宣传力度不足、科技生产力低下、网络融合度差等问题,进而就如何增强区域影响力、积极完善基础设施建设、与科技生产融合、培养高素质农业人才等方面为耕读园经营提出改善措施。  相似文献   

11.
桔园喷灌增产机理和灌溉制度探讨   总被引:2,自引:1,他引:2  
喷灌是柑桔等经济作物先进的灌溉方式,充分认为柑桔喷灌增产机理,采用合理的灌溉制度,对提高柑桔产量和品质有十分积极的意义。  相似文献   

12.
Using a binary logistic regression model, this paper evaluates the determinants of farmers’ decisions to adopt rainwater harvesting and supplementary irrigation technology (RHSIT) and its elasticity of adoption in the rain-fed farming systems, based on a survey of 218 farmers in the semiarid areas of Loess Plateau in 2005. The results indicate that 12 variables are significant in explaining farmers’ adoption decisions. Farmers’ educational background, active labor force size, contact with extension, participation in the Grain-for-Green project, and positive attitudes towards RHSIT are some of the variables that have significantly positive effects on adoption of RHSIT, while farmer's age and distance from water storage tanks to farmers’ dwellings have significantly negative correlation with adoption. The probability of adoption also increases with increased targeting of institutional variables: credit obtained, assistance obtained, and technical training received. Farmers in villages that have more erosion problems are more likely to adopt RHSIT. Besides, the model indicates that a 1 unit increase in the diversity of irrigated crops grown by a household, especially high-value crops, results in a 6.98 times increase in the probability of RHSIT adoption. Variables such as family size, off-farm activity, level of family income, risk preference, and land tenure do not significantly influence adoption. This information will help prioritize the factors that affect adoption decisions and provide insight on pathways to increase the adoption of RHSIT.  相似文献   

13.
为探索解决地下滴灌玉米出苗难的问题,通过土箱试验,对内蒙古自治区具有典型代表性的3种土壤,开展了毛管铺设参数(滴头流量、埋深)和灌水定额对地下滴灌湿润半径的影响规律试验,结合玉米播种深度、水分向上及向下运移的距离及种子周围土壤含水量,研究了玉米适宜出苗灌水定额,以提高出苗率,指导实际生产.结果表明:按显著性水平0.05检验,土壤类型和灌水定额均对土壤湿润半径影响具有统计学意义,而滴头流量和埋深对湿润半径影响不具有统计学意义.在黏壤土中,玉米出苗灌水定额37.5~52.5 mm基本可满足毛管埋深25~35 cm的出苗要求;在壤土中,玉米出苗灌水定额37.5 mm左右基本可满足毛管埋深25~30 cm的出苗要求,灌水定额52.5 mm左右基本可满足埋深30~35 cm的出苗要求;在砂壤土中,灌水定额22.5~37.5 mm基本可满足毛管埋深约25 cm的玉米出苗要求,灌水定额52.5 mm基本可满足毛管埋深25~35 cm的玉米出苗要求.  相似文献   

14.
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   

15.
Mass movement labor was an important contributor to irrigation system construction in China during the seventies, making up a third or more of system costs. Total per-ha system costs are roughly consistent with those in other Asian countries when contributed labor is valued at estimated farm wage rates, but less than average if zero labor opportunity cost is assumed.Innovative practices are being employed in managing and supporting irrigation system operations in Western Hunan Province. Many are ones which have been advocated repeatedly elsewhere but infrequently applied. These include the volumetric wholesaling of water to distribution organizations, farmer water charges with both fixed and volumetric components, financially autonomous irrigation management agencies, and delegation of water distribution and fee-collection responsibility to village-based organizations. Heavy emphasis currently rests on financial self-reliance of schemes as denoted by the slogan, let water support water. This has led to a proliferation of secondary income-generating enterprises associated with irrigation system management, as well as strenuous efforts to collect irrigation fees. Often the secondary enterprises generate a larger share of total income than does the irrigation service itself.Fee levels for rice generally fall into the $12 to $20 ha/yr range, intermediate to those prevailing in Pakistan at $8.50/ha for two crops of rice and the Philippines at $45/ha for double cropped rice. Collection of fees is typically handled by the village. Charges are usually levied on an area basis but one large system employed a more complicated system which had both fixed and variable components. Water allocation at lower system levels is also delegated to the village in many cases, with the state serving as a wholesale provider of water.Abbreviations and units ha-m hectare-meter - jin unit of weight equal to 0.5 kg - kw kilowatt - mu unit of land area equal to 1/15 ha - Rmb Renmimbi (Yuan) equal to US$ 0.27 officially in September 1988 and about half of that unofficially - RMD Reservoir Management Division - WCB Water Conservancy Bureau - WMD Water Management Department  相似文献   

16.
为研究畦面结构变化对地面灌溉效果的影响,在4种不同畦面结构的大田灌溉试验基础上,用WinSRFR3.1模型对平作畦灌、细沟灌、畦作浅沟灌和微垄沟灌的田面土壤特性参数和灌水效果进行估算和模拟,比较了不同灌溉方式由于畦面结构改变引起的田面土壤特性和灌水效果差异,并提出不同畦面结构的适宜畦田规格。研究认为,不同畦面结构的田面糙率系数和土壤入渗特性差异明显,微垄沟灌糙率系数最大而平作畦灌糙率系数最小,平作畦灌入渗速率最快而畦作浅沟灌入渗速率最慢;对长畦田来说,畦作浅沟灌灌水效果最好,微垄沟灌次之,平作畦灌最差;在  相似文献   

17.
This paper demonstrates the potential productive and economic advantages of designing for deficit (or under-) irrigation of selected crops in water short areas. The example presented is for the supplemental irrigation of rainfed coconut trees in the state of Kerala, India. In particular, the productive and economic advantages of designing drip systems for deficit irrigation as compared to standard drip systems designed for full irrigation to meet potential evapotranspiration is demonstrated.Paper developed in conjunction with the Transfer Course on Drip and Sprinkler Irrigation System Design and Layout, 7–25 January, 1991, at the Center for Water Resources Development and Management, Calicut, Kerala, India. This is a sub-activity of USAID's Indo-US Project, carried out by Louis Berger Intl. Inc. and Water and Power Consultancy Services Ltd.  相似文献   

18.
This paper examines several farmer managed irrigation schemes in the eastern hills of Nepal. The development and management structure of these is considered in order to identify characteristics of successful schemes which could be used in planning future projects.  相似文献   

19.
Customary evaluations of irrigation performance based upon crop yield per unit area do not reflect an adequate assessment of performance in water scarce environments such as Pakistan. Yield per unit water is a complementary and sometimes more appropriate measure. This note illustrates the different evaluations based upon yields of irrigated wheat and rice in Pakistan.  相似文献   

20.
Carbon (C) sequestration through irrigation management is a potential strategy to reduce C emissions from agriculture. Two experiments (Exps. I and II) were conducted to investigate the effects of different irrigation strategies on C retention in the soil-plant system in order to evaluate their environmental impacts. Tomato plants (Lycopersicon esculentum L., var. Cedrico) were grown in split-root pots in a climate-controlled glasshouse and were subjected to full irrigation (FI), deficit irrigation (DI) and alternate partial root-zone irrigation (PRI) at early fruiting stage. In Exp. I, each plant received 2.0 g chemical nitrogen (N), while in Exp. II, 1.6 g chemical N and maize residue containing 0.4 g organic N were applied into the pot. The results showed that, in both experiments, the concentration and the amount of total C in the soil were lower in FI and PRI as compared to DI, presumably due to a greater microbial activity in the two treatments; particularly the PRI induced drying and wetting cycles of the soils may cause an increase of microbial activities and respiration rate, which could lead to more C losses from the soil. However, in both experiments the total C concentration in the PRI plants was the highest as compared with the FI and DI plants, and this was seemingly due to improved plant N nutrition under the PRI treatment. Consequently, the total amount of C retained in the soil-plant system was highest in the FI and was similar, but lower, for the PRI and DI. The different N input in the two experiments might have affected the C retention in the soil and in the plant biomass. Nevertheless, with a same degree of water saving, PRI was superior to DI in terms of enhancing C concentration in the plant biomass, which might have contributed to a better fruit quality in tomatoes as reported by [Zegbe et al., 2004] and [Zegbe et al., 2006].  相似文献   

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