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林业种苗是保障林业资源持续性发展的关键,同时推动林业资源经济利益最大化的重要工作项目,在确保造林绿化方面有着决定性的作用。伴随着市场经济的持续性发展,自然环境也在不断的恶化,这也促使林业资源保护与开发工作的重要性不断提升。对此,为了更好的提升林业种苗管理水平,本文详细分析林业种苗管理措施及生产技术,希望可以为相关工作者提供一定帮助。 相似文献
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<正>方城县辖17个乡镇(街道办事处),总面积2 542 km~2,其中耕地面积1.13万hm~2,农作物总播种面积2.02万hm~2,2013年全县粮食生产首次突破6亿kg。方城县总人口106万人,其中农业人口95万人,农村劳动力57.6万人,剩余劳动力21万人,常年外出务工人员15万人左右,从事农业生产的人数为36.6万人,其中在家务农劳动力 相似文献
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油菜联合收获机筛面粘附物摩擦特性 总被引:6,自引:0,他引:6
The main ingredients and structure of rape adhesive materials on cleaning sieve were analyzed for sieve hole blocking and multiply increased cleaning loss caused by the adhesive materials. Size distribution of rape adhesive materials on cleaning sieve was obtained. 77% of the adhesive materials’ size were from 0.3mm to 2.5mm, and the main ingredients were distinctly different with different size range. Friction coefficient tests of rape nutshell, rape stalk & the adhesive materials were carried out. It was pointed out that their friction coefficients were commonly increased with the raise of their moisture, and the friction coefficients between the adhesive materials and metal reached to 0.71. 相似文献
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