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为了研制新型树木肥料,以自行研制有机-无机棒肥制作设备制作的有机-无机棒肥为研究对象,研究其对土壤理化性状和天竺桂生长的影响。结果表明:有机-无机复混棒肥主要指标满足有机-无机复混肥料GB18877-2002的基本要求,具有高压缩比、含有机成分、易操作等特点。施用有机-无机棒肥后土壤EC值均在1.0mS·cm-1以下,产生盐害的风险较小;对氮磷钾的提高效率大小顺序为磷氮钾;与未施用有机-无机棒肥的天竺桂相比,施用有机-无机棒肥能明显提高天竺桂的新梢长度、叶绿素含量和根重,对促进植物生长的作用明显。 相似文献
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不同打叶参数对打叶质量的影响 总被引:3,自引:0,他引:3
[目的]了解不同框栏尺寸、打棍转速的强度、曲线和斜率对打叶质量的影响。[方法]用山东地区的B2L和C3L两个等级的烟叶进行打叶试验。[结果]3.0英寸的框栏比3.5英寸的框栏更有利于改善打叶风分后的烟片结构,大中片率、中片率、长梗率均略有提高,碎片率有所降低。3组打棍转速强度的打叶强度逐组递减,而每组当中4级打叶强度逐级增强。提高打叶机的打辊转速强度利于提高打叶风分后烟片的中片率和长梗率,并能降低叶中含梗率。不同打辊转速曲线对中片率和碎片率的影响不明显,但可使DC22获得较高的大中片率和长梗率。较小打辊转速斜率能使打叶质量有所改善,并较明显地提高中片率。[结论]通过调整打叶框栏尺寸和打辊转速能有效提高烟草的打叶质量。 相似文献
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在甘孜州,用附着有蜜环菌菌索的野生天麻块茎进行组织分离获得的菌株作菌种,毛樱桃和刺叶栎一类的灌木作主要营养源,玉米和马铃薯作辅助营养源,培养瓶装菌枝,既可以有效发展天麻家栽,提高天麻产量和质量,满足其市场需求,又能够防止野生天麻资源因乱采滥挖而枯竭,防止相关资源因发展天麻家栽而毁灭的一项合理的技术措施。 相似文献
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The appropriateness of three official fisheries management reference points used in the north‐east Atlantic was investigated: (i) the smallest stock size that is still within safe biological limits (SSBpa), (ii) the maximum sustainable rate of exploitation (Fmsy) and (iii) the age at first capture. As for (i), in 45% of the examined stocks, the official value for SSBpa was below the consensus estimates determined from three different methods. With respect to (ii), the official estimates of Fmsy exceeded natural mortality M in 76% of the stocks, although M is widely regarded as natural upper limit for Fmsy. And regarding (iii), the age at first capture was below the age at maturity in 74% of the stocks. No official estimates of the stock size (SSBmsy) that can produce the maximum sustainable yield (MSY) are available for the north‐east Atlantic. An analysis of stocks from other areas confirmed that twice SSBpa provides a reasonable preliminary estimate. Comparing stock sizes in 2013 against this proxy showed that 88% were below the level that can produce MSY. Also, 52% of the stocks were outside of safe biological limits, and 12% were severely depleted. Fishing mortality in 2013 exceeded natural mortality in 73% of the stocks, including those that were severely depleted. These results point to the urgent need to re‐assess fisheries reference points in the north‐east Atlantic and to implement the regulations of the new European Common Fisheries Policy regarding sustainable fishing pressure, healthy stock sizes and adult age/size at first capture. 相似文献
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插穗母树年龄和粗度对薄壳山核桃硬枝扦插的影响 总被引:2,自引:0,他引:2
探讨薄壳山核桃不同母树年龄和不同粗度对插穗生根能力的影响,采用1年生硬枝进行扦插试验.母树选择2、5、16年生和25年生,采用IBA-0.2 g· L-1处理插穗.插穗粗度设为≤0.5、0.5~0.8、≥0.8 cm3个径级,插穗用不同浓度的IBA、NAA进行处理.结果表明,2年生母树穗条的愈伤组织产生率和生根率分别为87.7%、14.4%,明显高于其他年龄母树.插穗粗度≥0.8cm穗条的效果最好,其平均愈伤组织产生率和生根率分别达33.1%和9.7%.≥0.8 cm穗条的IBA1.0 g·L-1+NAA0.25 g·L-1混合液处理效果最佳,2个指标分别达43.0%和14.6%.相同母树年龄的插穗其愈伤组织产生率和生根率与粗度成正相关. 相似文献
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采用非接触式测温测速、单片机控制及机电一体化技术,研制出便携式加热磁力搅拌器.使其在结构、性能上实现了轻型化、微型化、智能化,并提高了搅拌浸提效率. 相似文献