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近几年来，一些发达国家为提高农药喷洒的效率和减少农药喷洒时对人体的伤害，农药喷洒机械正趋向自动化。 韩国的泰仁技术开发公司，经过两年多时间的研究，开发研制成功一种无人农药喷洒机。这种无人农药喷洒机的核心部件，是喷洒农药的喷头。它由电子精密陶瓷制成，具有电动控制功能，能将农药自动均匀地喷洒到农作物叶片的两面，达到理想的杀虫效果。用于温室、塑料大棚和果树林等地的杀虫作业时，可安装在轨道上，用蓄电池驱动，实施无人喷洒作业。这不仅能省时、省力、省农药，而且还可避免农药对人体的伤害，十分安全。 美国斯坦福大… 相似文献
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３ＷＤ─２００型吊杆喷雾机的使用操作及注意事项３ＷＤ—２００型吊杆喷雾机是防治棉花病虫害的专用机具，也可对农作物喷洒除草剂和各种微量元素及叶面施肥作业。一、喷洒除草剂１．地膜棉喷洒除草剂。在播前整好地的基础上喷洒氟乐灵，每亩用量１００毫升，兑水５０～... 相似文献
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提高农药的利用率、降低污染，一直是农药喷洒技术的一个发展方向。为此，从分析传统农药喷洒方法入手，阐述了传统方法污染大、浪费严重的弊端，并在论述激光扫描成像系统原理的基础上，介绍了一种利用该成像装置的机载农药喷洒方法。有关实验数据表明，该方法具有节约、环保、高效等优点，具有极好的推广应用前景。 相似文献
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《中国农村水利水电》2005,(1):26
“喷洒型防水技术”就是根据工程需要，选择不同特点的喷洒型防水剂，直接喷在符合设计施工要求的各类建筑物体上，形成防水屏障达到不同程度防渗、防水效果的一项技术。被喷洒的建筑物体主要包括：混凝土、水泥砂浆、水泥素浆、浆砌石、砌砖、水泥土等。 相似文献
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针对涡轮式草坪喷头变域喷洒的要求，根据正方形喷洒域的旋转角度－射程以及工作压力－射程边界方程，得出了变域喷洒系统所需提供的时间－工作压力模型。应用变频调速技术，建立了变域喷洒系统供水的控制结构和系统传递函数，采用MATLAB进行了模拟仿真，利用临界比例度法确定PID控制参数，从得到的系统响应特性可以看出：响应时间约30s，超调量很小，调节效果较好，为今后进一步开展变域喷洒喷头的试验验证研究提供了理论基础。 相似文献
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农用多喷头喷雾机设计参数的确定 总被引：1，自引：0，他引：1
根据环保和植保机械对作物的喷洒要求，提山了多喷头的喷射角、喷头个数、喷头间距、调节角度、喷洒均匀性等参数的确定方法，为农用喷雾机的设计和生产提供可靠的理论依据。 相似文献
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一种新型的节水灌溉技术——渗灌 总被引：18，自引：3，他引：18
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
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William P. Field 《Irrigation and Drainage Systems》1990,4(2):91-107
Land under irrigation in the world today, about 250 million ha, makes up about 17% of the total area cropped world-wide and contributes 36% of the world's food production. About three-quarters of the irrigated area is in the so-called developing countries. Of this, 90% is concentrated in North Africa and the Near and Far East. In contrast, sub-Saharan Africa contributes less than 2%. Irrigation technology differs between regions, not only according to climatological factors, but also to historic and socio-economic influences. 相似文献
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自流灌区节水灌溉及其对策 总被引：1，自引：0，他引：1
随着全球化水资源危机的出现,灌区发展中存在的问题明显暴露出来。一方面,灌区工程老化失修严重,灌水技术落后,管理粗放;另一方面,水资源不足,灌区引水量逐年下降,制约 了灌溉效益的发挥和灌区的发展。 相似文献
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Olufemi Olukunle Olubode-Awosola Ezekiel Olukayode Idowu Herman Daniël Van Schalkwyk 《Irrigation and Drainage Systems》2006,20(2-3):303-315
This study examines the socio-economic and financial performances of irrigation projects under the Ogun-Oshun River Basin and Rural Development Authority (O-ORBRDA) in Nigeria. Primary data on the farming activities of the project farmers during the 2001/02 seasons and the projects' records for the period of 1995/96 to 2001/02 were summarised into socio-economic and financial performance indicators. In the Sepeteri Project, a revenue recovery level of 96% was estimated. The project is not financially viable as only 29% of its recurrent expenditure is covered. The farmers do not show commitment to making the project successful. An approximate 67% social capacity level was estimated. The relative irrigation cost and profit indexes do not show sufficient evidence that farmers would prefer irrigation farming to rain-fed farming. The Itoikin Project records a lower revenue recovery level of 75%. The project covers about 50% of its recurrent expenditure. In addition, the farmers do not appear to have a commitment to making the project successful, with a 33% social capacity level. A number of problems may be the causes of unprofitable irrigated cropping. If government increases the subvention, the O-ORBRDA prioritises irrigation service in disbursing the subvention to the projects, and the project manages the risks in the project sites, conscientises and incorporates the intended beneficiaries into managing the projects, the projects would be equipped to supply more irrigation services thereby making it more profitable and encouraging more participation of the intended beneficiaries. This would improve the socio-economic and financial performance of the projects. 相似文献
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《Agricultural Water Management》2004,64(1):17-27
In northern Ethiopia, where traditional (farmers) irrigation management on Vertisols is widely practiced, sustainable food security has always been a challenge. The reasons for this are multi-dimensional, but of utmost importance is, low-tech irrigation water management. The main objective of the present study is, therefore, to examine technologies of irrigation water management that might enable farmers to increase water productivity (WP) on vertisols.A comparative study has been undertaken between the traditional irrigation management (every furrow-traditional scheduling) and alternative water management options on maize plots in northern Ethiopia. The options include alternate furrows-scientific scheduling and every furrow-scientific scheduling. A field experiment was undertaken over two irrigation seasons (1998/1999 and 1999/2000). Results were compared on the basis of yield, WP and economic productivity concepts.Yield-based comparison has shown that every furrow-scientific scheduling generates the highest yield levels followed by alternate furrows-scientific scheduling. The yield increase (by every furrow-scientific scheduling) over the traditional management was found to be 54%.WP-based comparison has shown that alternate furrows-scientific scheduling generates the highest WP values followed by every furrow-scientific scheduling. The increase (by alternate furrow irrigation, scientific scheduling) over the traditional irrigation management was 58%.Economic productivity-based comparison has shown that the highest economic return was obtained from every furrow-scientific scheduling followed by alternate furrows-scientific scheduling. The increase in income (by every furrow-scientific scheduling) over the traditional irrigation management was 54%.The overall observation is that depending on the availability of water and labour resources, one can decide to use either of the alternate management options to obtain economically reasonable yield. In northern Ethiopia, where water is limiting (and not labour), every furrow-scientific scheduling can be an option. 相似文献
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介绍了一种新型喷灌和软管灌溉两用轻小机组的结构和工作原理,该新型灌溉机组由绞盘车提供行走动力和压力水源,通过喷水车进行喷洒灌溉.机组可配置喷灌和软管灌溉两种不同的灌水系统,满足了不同作物在不同生育期对水分的要求;喷水车安装有高度调节装置,始终使灌水器处于最佳灌水高度;机组上采用低压折射式喷头和软管洒水带等低压灌水系统,使机组的工作压力降低了30%.通过对该机组水涡轮特性、运行特性、喷洒特性的分析,确定了该机组的技术参数.喷洒试验表明,新型灌溉机组可克服受风影响较大的弱点,减少灌溉水分的漂移损失,灌水均匀度可达90%. 相似文献
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Beyond irrigation efficiency 总被引：3，自引：2，他引：3
Marvin E. Jensen 《Irrigation Science》2007,25(3):233-245
Parameters for accounting for water balance on irrigation projects have evolved over the past century. Development of the
classic term irrigation efficiency is summarized along with recent modifications such as effective irrigation efficiency. The need for terms that describe measurable water balance components of irrigated agriculture is very important, as demands
and competition for available renewable water supplies continue to increase with increasing populations. Examples of irrigation
efficiency studies conducted during the past few decades are summarized along with related irrigation terminology. Traditional
irrigation efficiency terminology has served a valid purpose for nearly a century in assisting engineers to design better
irrigation systems and assisting specialists to develop improved irrigation management practices. It still has utility for
engineers designing components of irrigation systems. However, newer irrigation-related terminology better describes the performance
and productivity of irrigated agriculture. On a river-basin level, improved terminology is needed to adequately describe how
well water resources are used within the basin. Brief suggestions for improving irrigation water management are presented. 相似文献
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Ruth Meinzen-Dick 《Irrigation and Drainage Systems》1995,9(4):371-387
Despite considerable discussion of the importance of timeliness as a key dimension of irrigation performance, few studies have assessed how well irrigation systems deliver timely water supplies, nor the magnitude of the effect on agricultural production. This paper lays out indicators of timeliness of irrigation supply which distinguish between deliveries which meet crop needs, and surplus water supplies which cannot be used by crops. These indicators are then applied to empirical data from the Sone Irrigation System of Bihar, India. Using these indicators in an analysis of the contribution of irrigation to rice production shows that incorporating measures of timeliness explains much more of the variability in agricultural production than do simple measures of total water applications over a season. Results of production functions show that if water deliveries cannot be matched with crop requirements, they have a negative, rather than a positive, impact on yields. Water scarcity has the greatest adverse impact in production in the middle of the season, while surpluses are most damaging at the beginning and end of the season. Temporal redistribution from surplus periods to times of water scarcity therefore offers considerable scope to increase productivity without increasing water use.An earlier version of portions of this paper was presented at the IFPRI/ICAR Workshop on Agricultural Growth in India: A Review of Research Findings, 1–6 May 1994 in New Delhi. 相似文献
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Florida ranks first in citrus production, with nearly 68% of all U.S. citrus growing in the season 2005-2006. Most of the citrus groves are located from central to south Florida, and agricultural irrigation permitting is regulated by three of Florida's five water management districts. Most of the permitting for citrus production in Highlands, Polk and Hillsborough counties is conducted by the Southwest Florida Water Management District (SWFWMD), and quantities are based on the District's AGMOD computer program. In 2003, the SWFWMD implemented new permit criteria so that permitted amounts were more representative of actual water use. This paper compares grower reported citrus irrigation water use in Highlands, Polk and Hillsborough counties from 1994 through 2005 with permitted and theoretical irrigation requirements calculated by a daily water balance. Two different sets of crop coefficients (Kc's) developed for citrus in Florida were compared in the daily soil water balance calculation of theoretical irrigation requirements. The percentage of irrigated area considered in this study ranged from 40 to 60% to simulate a range of grower practices. Meteorological data from two weather stations and additional rainfall information from 50 locations within the three counties was used in the water balance. Missing and error values in the meteorological historical record data were filled with weather generators. The multiannual average water consumption (including cold protection water use) from growers ranged from 243 (Hillsborough) to 406 mm (Highlands) and the multiannual average permitted irrigation requirement (without cold protection) ranged from 295 to 557 mm. The simulated gross irrigation requirements under different scenarios of location-Kc-wetted area were variable but mostly lower than the limits established by the district, except for some scenarios in Polk County, whose maximum simulated irrigation value reached 578 mm year−1. In general, permitted limits recommended by the SWFWMD seem to be reasonable for the actual water use by growers in these counties. 相似文献
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The effect of irrigation dynamics and soil physical properties on the permissible rate of application was analyzed using the
analytic solution of Richard’s equation for periodic flux type boundary conditions typical to high frequency irrigation. Dynamics
of irrigation regime was defined by its instantaneous application rate, R
0, its frequency, and the duty cycle which is the ratio of irrigation duration and irrigation interval (period). Soil properties
were saturation, hydraulic conductivity, diffusivity, and Gardner’s soil type coefficient. Fourier Transform was used to derive
a closed form analytical expression for the maximal permissible value of R
0, which would not result in water logging and saturation at soil surface. The analytical expression ties the three irrigation
parameters with the above three soil parameters together. Prevention of aeration stress by restricting the moisture content
at the soil surface, to become less than the minimal air pore volume (drainable porosity), was also used as an upper constraint
of moisture at the surface soil. The effect of irrigation frequency and duty cycle on the permissible R
0 values was analyzed and computed regarding three soil types: coarse sand, sand, and sandy loam. Under short duration periods
of water application resulting from either small values of duty cycle or short irrigation periods (high frequency), or both,
the soil surface would not become saturated even for very high R
0 values. The maximal application depth V
max, depends on both the duty cycle and the frequency. For a given soil, V
max remains essentially constant per irrigation periods of 1 h or less, typical to pulsed irrigation and independent of the duty
cycle. For periods longer than 1 day for coarse soils, V
max increases with the duty cycle while for sandy loam soils, the increase in V
max becomes insignificant for duty cycles larger than 0.3. The computed values of maximal R
0 and V
max based on the water logging concept are much higher than the ones used in irrigation design and should be considered as upper
permissible limits only. The permissible values of R
0 and V
max are much lower if the aeration stress concept is adopted and found in the range used in practice. This analysis may be useful
for the design of precision irrigation for high frequency microdrip, high frequency trickle irrigation, as well as for trunk
diameter measurement (TDM) irrigation methods. 相似文献