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红叶石楠扦插育苗技术 总被引:2,自引:0,他引:2
在查阅有关文献和总结育苗经验的基础上,从苗圃地的选择与规划、采穗圃的营建及管理、扦插技术、苗木移栽及病虫害防治等方面总结了红叶石楠无性扦插育苗技术,为红叶石楠苗木的规模化生产提供参考。 相似文献
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详细分析了无卡轴旋切机的工作原理,推导了旋切过程中刀刃进给速度与圆木直径的数学模型,同时得出旋切时间的近似计算式。从中可知,旋切过程中刀刃进给速度必须按一定规律变化才能保证旋切机正常工作。建立了旋切机恒线速旋切的运动轨迹模型,推导出旋切机恒线速旋切时间的精确计算式,并在此基础上提出了旋切时间简便的近似计算式。这些研究结果均可用于指导设计和进行实际生产。 相似文献
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Two trials were carried out over five growing seasons in western Tanzania to investigate (a) forage production and quality of eight lines of Leucaena leucocephala, one of L. diversifolia and one of L. esculenta and (b) the effect of cutting height (25, 50 and 75 cm) on forage production of nine lines of L. leucocephala and one of L. diversifolia. The locally naturalized lines, T1 and K1, were consistently better in yield, out-producing the commercial L. leucocephala cultivars Cunningham, Peru and K8 in three or four out of the five seasons' harvests. Mean daily dry matter yields for all lines decreased as the dry season progressed. Mean yields were 54.9, 28.6 and 12.8 kg/ha/day in the rainy season, late rainy season/early dry season and late dry season, respectively. The concentrations of N (2.3 to 3.1%), P (0.13 to 0.17%), K (0.7 to 1.3%), Ca (0.6 to 1.6%) and Mg (o.4 to 0.6%) in the edible forage declined as the dry season became pronounced but were at levels sufficient for animal production except for P levels, which were low. Three distinct yield groups emerged from responses to cutting height: cv. Cunningham produced the greatest yields of edible forage at 25 cm cutting height; cv. Peru, cv. K8, Korog, T1, CpI 90790 and CPI 58394 at 50 cm; and CPI 58398, CPI 84511 and CPI 85132 at 75 cm. 相似文献
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Jaime Villacís Cristina Armas Susana Hang Fernando Casanoves 《Land Degradation \u0026amp; Development》2016,27(7):1771-1780
One of the requirements for the forest restoration of soils disturbed by the oil‐exploitation industry is that saplings be able to endure soil‐adverse conditions. In this study, saplings of 20 species susceptible to be used in reforestation programs were evaluated for their ability to grow on substrates derived from soils disturbed by petroleum extractions in the Ecuadorian Amazon. Seeds of each species were planted in germination trays. Once seedlings reached 5 cm in height they were transplanted to plastic bags with three treatment substrates: two derived from petroleum‐exploitation activity (soils from mud and drill cutting cells and from areas surrounding oil wells) and a control soil. Plant survival rate, stem height, and diameter were measured on a weekly basis until 14 weeks after transplantation, when we harvested the plants and also measured plant biomass and calculated the Dickson quality index for each species. Oil‐exploitation by‐product substrates impaired the performance of many saplings, with the substrate from mud and drill cutting cells being the one that most affected plant performance. Only saplings of five native species in the Amazon basin—Apeiba membranaceae, Cedrelinga cateniformis, Inga densiflora, Myroxylon balsamum, and Pouroma cecropiifolia—exhibited high or similar Dickson quality index values in all soil treatments and performed better than the rest. The use of these five species in remediation of soils disturbed by petroleum extraction in the Amazon basin could prove important because of their high potential to adapt to these disturbed sites. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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对造纸行业切纸用的各种小型圆刀结构及研磨设备进行系统研究,研制出专用磨床,并对其传动原理、基本结构、安装调试、配套夹具设计等进行了介绍。 相似文献
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