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<正>杂交棉在新疆推广应用以来,棉花单产、总产大幅提高。棉花高产栽培技术是一个系统工程,只有掌握了品种特性,根据所在地区的气候特点、耕作制度、土壤肥力状况和种植方式等,配合相应的高产栽培技术,才能获得杂交棉高产。为此,对高产田棉花植株的生育参数及栽培技术进行示范研究。 相似文献
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董刚 《四川畜牧兽医学院学报》2013,(5):168-170
随着历史的发展和社会的进步,作为中华民族优秀传统文化的中国武术在满足社会需要、调整自身结构的同时,其价值体系也在不断地演进。运用文献资料法、系统分析法、逻辑分析法,立足当代社会生活实践,从主体的当代需求角度就武术的生活价值、精神价值、方法价值和负价值几个层面进行系统的分析,并提出武术中包含着负价值这一全新命题。 相似文献
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运用聚集度指标法、Iwao 回归分析法、Taylor幂法则对柽柳上的斯氏伞锥象成虫的空间分布型进行测定检验,结果表明斯氏伞锥象成虫在柽柳上呈聚集分布,分布基本成分是个体群,聚集强度随种群密度升高而增加.其种群聚集均数λ>2,说明聚集原因是昆虫本身习性和环境共同引起的或由其中一个因素引起的.根据Iwao最适抽样公式得出了理论抽样模型:N=(t2)/(D2)((3.860 7)/(m) 0.139 6),并计算出不同虫口密度、不同允许误差下的理论抽样数. 相似文献
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泥鳅扰动对水田沉积物颗粒垂直分布的影响(英文) 总被引:1,自引:0,他引:1
[Objective] The purpose of this study was to investigate the role of breeding Misgurnus anguillicaudatus in paddy field in vertical distribution of sediment particles. [Method] Using chemically stable glass beads as tracers, the effects of Misgurnus anguillicaudatus bioturbation on the vertical distribution of sediment particles in paddy field were investigated, and the bioturbation role of benthic fish in the coupling process of benthic-pelagic interface was discussed. [Result] After ten days of Misgurnus anguillicaudatus bioturbation, 43.2% of the glass beads on the surface were transferred downwardly with the maximum distance of 7.5 cm, and the vertical transportation rate of sediment particles was 7.676×10-4g-1·cm-2·d-1. At a depth of 6 cm, 39.7% and 9.9% of the glass beads were respectively transferred upwards and downwards, to the maximum distanc of 4.5 cm and 5.1 cm, respectively; and the vertical transportation rates of sediment particles were 7.597×10-4g-1·cm-2·d-1 and 1.894×10-4g-1·cm-2·d-1, respectively. [Conclusion] Misgurnus anguillicaudatus bioturbation could promote the circulation and transformation of nutrients at water/soil interface through affecting the vertical distribution of sediment particles. 相似文献
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挤锥口工艺的应用(152071)绥化林业机械厂董刚,张风柱在制造图1所示的齿轮时,因其上下两端壁厚图1齿轮工件图差太大,在拉削矩形花键时引起工件上下两端孔径不一致,特别是热处理后变形更大,工件质量难以保证.经研究发现,热处理后工件上端孔径都比下端孔径... 相似文献
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记者从3月19日全省林业局长会议获悉,我省今年计划造林550万亩,并按照工程分解落实。为确保高标准、高质量的完成既定目标,省林业局制定了“狠抓三大举措,办好两件大事,完成两大任务”的全年工作重点。 相似文献