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论影响喷灌发展的几个非技术因素 总被引:1,自引:0,他引:1
为了使喷灌技术得以健康发展,在回顾甘肃喷灌发展历程的基础上,分析提出了土地经营模式、水价及农产品市场、农民文化素养、对喷灌优缺点的认识以及经济发展水平等影响喷灌发展的几个非技术因素,并就此提出了甘肃今后发展喷灌的思考和建议。 相似文献
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1土地规模经营形式及现状 土地规模经营即指在稳定土地承包经营30年不变的基础上,本着自愿、平等、互利的原则,通过反租倒包、切块置换、折股经营等土地经营流转形式将土地向种田能手或农业企业集中的一种经营模式。在南县农村.由于中央两个1号文件的贯彻落实,政府对农业的扶持力度大大加强,农民种田积极性高涨。前几年由于农产品价格低迷以及洪涝灾害导致抛荒的耕地, 相似文献
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分析了农业机械的快速发展与土地分散经营的种植模式之间的突出矛盾,论述了加快土地流转、实现规模化经营、促进农机化发展的重要性,并对土地流转提出了一些建议和意见。 相似文献
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我国喷灌发展五十年回顾 总被引:3,自引:0,他引:3
为了对我国的喷灌发展有一个全面的认识,首先总结介绍了我国喷灌发展所经历的四个阶段,再概括出我国喷灌技术及其研究发展过程,并通过国内外的对比分析,找出了我国喷灌存在的突出问题,最后,就喷灌在我国应用中的几个重要的基本概念加以讨论和明确,以达到对我国喷灌进行再认识的目的。 相似文献
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农五师81团目前已有相当一部分新开垦土地实施了喷灌工程,取得了可喜成果。然而这些灌溉形式只限用于大面积,土地条件较好的土地.而且喷灌配套投资大.一般在土地条件差、地形复杂.连队废弃土地上很难应用,特别是小规模开垦的土地,用户很难使用、我们采用了小型喷灌设施进行灌溉,投资少,设备简单.安装使用方便.农户都能接受。l小型喷灌设施的配套配套可采用二种方法:一种选用11.Ikw小四轮拖拉机与离心泵配套;另一种采用柴油机与水泵配套。水泵流量IOOm’/h,扬程32n。,配套喷灌管(单排)ZO根.每根长sin.每个喷头喷灌面… 相似文献
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市场经济条件下的农机经营模式 总被引:1,自引:0,他引:1
分析了国内外农业机械化的发展状况及我国农业机械化发展过程中存在的问题;研究了我国传统的农机经营模式(即在计划经济和从计划经济向市场经济过渡阶段条件下的农机经营模式)及其存在的问题;提出了一种在市场经济为主体条件下的农机经营模式,即农机服务合作股份有限责任公司。这对我国农业机械化的发展和经营有一定的参考价值。 相似文献
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论土地流转与农机化发展 总被引:1,自引:0,他引:1
分析了农业机械的快速发展与土地分散经营的种植模式之间的突出矛盾,论述了加快土地流转、实现规模化经营、促进农机化发展的重要性,并对土地流转提出了一些建议和意见. 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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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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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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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