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苗木栽植与养护是园林绿化的重要环节,苗木的成活率和生长状况直接影响园林绿化效果.阐述城市园林绿化苗木栽植与养护中存在的问题,详细介绍科学的苗木栽植与养护技术要点,以期为保证苗木健康生长、实现绿化效果提供参考. 相似文献
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随着社会的进步,可持续发展理念深入人心,针对具有绿化功能的苗木所开展的培育、栽植和管理工作,引起了人们的高度关注。文章以绿化苗木的培育,栽植、培育和管理现状为立足点,首先以"绿化苗木的培育"为题,展开了相应的讨论,然后又通过理论与实际相结合的方式,分别以绿化苗木的栽植和管理为切入点,进行了深入的探究,以供相关人员参考。 相似文献
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我国北方城市在最近几年加快了发展进程,使得园林绿化建设变得越来越重要,绿色苗木产业的发展进入了快车道。绿化苗木在中国北方农业产业中扮演着重要角色。我国北方的冬季至早春期间,气温骤降、风力增大、温度变化幅度大、持续时间长。寒冷的天气对苗木有直接的冻害,也有造成冻拔和冬季旱害等间接的危害。早晚霜引起苗木冻拔的原因是土壤中的水分结冰后膨胀,从而导致苗木根部因被拔起而死亡。苗木内部水分冻结会直接伤害植物细胞,导致苗木失去生理功能,最终导致植物死亡。因此,为了抵御寒冷和干旱,必须采取相应的保护措施。本文对北方园林苗木越冬难题进行了针对性的总结,提出了简单经济的防护措施。为了确保绿化苗木在寒冷的冬季安全地越冬,我们需要提供相关的技术支持和理论依据。 相似文献
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为进一步推进生态文明建设,提升城市人口生活质量,改善城市环境,园林绿化逐渐成为城市建设与管理部门的关注重点,如何确保苗木正常生长以及提升苗木的存活率逐渐成为园林绿化管理中的热点问题.本文结合现阶段我国园林绿化工作中的实际情况,从绿化苗木的种植施工以及日常养护技术两个关键方面入手展开探究,希望能够为目前我国城市园林绿化带... 相似文献
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森林覆盖率的提高和生态环境的保护有赖于林业种植,因此,对林业的生产和发展提出了更高的要求.林业生产力苗木的质量和数量对林业生产水平具有直接的作用,苗木育苗管理技术对苗木的整体质量产生直接的影响,在林业育苗的实际角度分析的基础上,应该不断发展育苗管理技术,从而促进林业育苗工作的规范化和专业化.本文主要分析了林业育苗管理技... 相似文献
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随着人们对居住环境的要求提高,城市发展也加大对园林绿化的建设,因此苗木的栽植和养护技术也得到了关注和重视,文章将对园林绿化的苗木栽植及养护技术展开探讨. 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