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作 者:周福成 Zhou Fucheng(The Total Saihanba Mechanical Forest Farm,Hebei Province,Chengde 068466,China)
机构地区:[1]河北省塞罕坝机械林场总场,河北承德068466
出 处:《防护林科技》2018年第10期1-2,12,共3页Protection Forest Science and Technology
基 金:国家自然基金项目:基于森林空间结构的华北落叶松人工林种子萌发及幼苗成活机制研究(31500523);河北省林业厅科学技术研究计划资助项目(1705488)
摘 要:通过对塞罕坝国家级自然保护区内落叶松林进行森林抚育,并对其生长变化进行测定,结果表明:林分进行森林抚育的3次生长率都是增加,但生长率增长的年数不同,第1次抚育时间最长,为5年;其次为第2次抚育,为4年;最后为第3次抚育,增长年数为3年。3次抚育生长率增长的最大值也是不同的,第1次抚育是最大的,为13.8%;其次为第2次抚育,为10.6%;最后为第3次抚育,生长率为9.7%。林分进行抚育后生长率变化规律是先增加后下降,呈正态曲线的变化趋势,说明其生长速度由于生长空间增大而加快。Through the forest tending of Larix gmelinii pure forest in Saihanba National Nature Reserve,the growth changes were measured.Result shows that the three growth rates of forest tillage increase;the number of years is different,the first is the longest,being five years;followed by the second,four years;finally the third,the growth is three years;the maximum growth rate of the three tending growth rate is also different,the first tending is the largest,being 13.8%;followed by the second tending,which is 10.6%;finally the third tending,the growth rate is 9.7%;the growth rate of the stand after the tending increase firstly.After falling,it shows a trend of normal curve,indicating that its growth rate is accelerated by the increase of growth space.
分 类 号:S791.22[农业科学—林木遗传育种]
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