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在对宁夏节水灌溉技术应用现状深入调查研究的基础上,根据不同灌区水资源及作物种植条件,结合各种节水灌溉技术实际应用情况,以工程技术、农艺技术和管理技术为要点,分析总结出设施农业等9种节水灌溉技术应用模式.这些技术模式在生产中已取得了较好的应用效果,并将在实践中进一步提高和完善,对发展应用节水灌溉技术有着重要的技术指导作用和推广应用价值. 相似文献
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新疆干旱区节水灌溉工程技术发展模式研究 总被引:1,自引:0,他引:1
以新疆干旱区农业节水灌溉工程技术应用实际为基点,采用收集资料与实地调查研究相结合、现场试验与理论分析相结合的技术路线,主要针对新疆内陆干旱地区特殊的自然条件和节水农业生产实际,重点对新疆节水灌溉分区和各分区适宜的节水灌溉工程技术进行了分析研究,并提出了适宜各分区的节水灌溉工程技术发展模式。为推动新疆干旱区节水灌溉工程技术的发展和水资源的优化配置提供了科学依据。 相似文献
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对我国北方地区几种节水灌溉工程技术模式的探讨 总被引:3,自引:0,他引:3
我国北方地区正在大规模发展节水灌溉,各地结合自身的特点采用了不同的节水灌溉工程技术模式,其中比较有代表性的有城郊设施农业节水高效工程技术模式、平原纯井灌区生态农业节水灌溉工程技术模式、丘陵水库灌区自压管道输水灌溉工程技术模式、引河补源渠井结合灌区节水灌溉工程技术模式、低山丘陵区河道截渗拦蓄和高位水池联合供水的节水灌溉工程技术模式、经济发达地区减轻劳动强度和提高生产效率的节水灌溉工程技术模式。为使这些模式更加完善,特对各种模式的内涵、适用性及与之有关的一些技术问题进行探讨。 相似文献
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基于农户满意度的农业节水技术公司化服务模式指标体系研究 总被引:1,自引:0,他引:1
农业节水技术公司化服务模式,以公司化为载体采用技术有偿服务的方式进行整建制推进高效节水的发展,能够有效地优化配置资源,减少成本,增加生产效益。农户满意度是公司化服务模式能否可持续发展的重要影响因素,以农户满意度为基础,从公司提供服务特征、农户个体特征、农民家庭特征和农业生产经营特征4个层面构建一套科学合理的指标体系,有利于对农业节水技术公司化服务模式能否可持续发展进行科学、全面、客观、公正的评价。 相似文献
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威海市节水农业综合评价研究 总被引:1,自引:0,他引:1
针对沿海地区水资源紧缺的问题,结合我国节水农业的发展现状,以威海市为例对其进行了节水农业综合评价指标体系及评价模型的研究,构建了节水农业综合评价指标体系,建立了多层次模糊综合评价模型,优化了评价理论和方法。结果表明:威海市节水农业发展良好,所建立的评价体系、评价方法及评价模型科学合理。该研究为沿海缺水区节水农业的综合评价提供了可操作的技术,对正确实施节水农业工程的管理具有指导意义。 相似文献
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《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
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感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
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The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献
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从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性,认为在缺水不可避免的情况下,对供水进行优化调度可以减小缺水带来的损失,产生较好的减灾效益,特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性,提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献