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作 者:王为斌
出 处:《延边大学农学学报》2004年第2期81-86,共6页Agricultural Science Journal of Yanbian University
摘 要:对黄菠椤母树林丰产型结构进行研究,结果表明,黄菠椤母树林最佳的雌雄比例为1:1,35-40年生黄菠椤单株母树稳产高产的营养面积为25.4 m2.林木级中Ⅰ-Ⅱ级林木是优良的林木级,Ⅲ级林木是被陶汰的林木级;母树结构中Ⅰ-Ⅱ级结构是优良的母树群体;树型结构中最佳的冠幅宽为4.7 m,冠长越长越好。The high-yield struction of seed forest of amur cock-tree was researched and the results indicated that the best male and female ratio was 1:1. Its growing space was 25. 4 m2 which had grown 30-40 years and had high and stable yields. The Ⅰ-Ⅱforest level was fine forest and the Ⅲ forest level should be sifted out. The Ⅰ-Ⅱ structure of seed forest was fine seed forest population. The best crown width was 4.7 m, and the longer crown length, the tree situation was better.
分 类 号:S758.53[农业科学—森林经理学]
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