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机构地区:[1]河北省孟滦林管局,河北围场068450 [2]河北农业大学,河北保定071001
出 处:《河北农业大学学报》2005年第3期45-48,共4页Journal of Hebei Agricultural University
摘 要:树冠是树木的重要组成部分,其数量指标———树冠圆满度不仅客观地反映了树木占有生长空间的状况及竞争能力,而且对树木的生长过程和树木的形状都有着非常重要的影响。研究结果表明:在树木直径、树高较小(或年龄小)时,其树干材积也较小,而树冠圆满度较大,随着直径、树高的增加,其树干材积随之增加,但树冠圆满度逐渐变小。所以,树冠圆满度与直径、树高及树干材积之间存在着紧密的相关关系,其相关指数(R)基本上在0 80以上,而形数与树冠圆满度之间呈正相关。The crown is an important portion of a tree. Meanwhile, the quantity index-crown-fullness ratio is not only reflecting the state of growth space of trees, but also affecting the growth process of trees and the form of tree-trunk. The result shows the smaller the diameter, height, the trunk volume of the tree, the larger the crown-fullness ratio and the larger the diameter, height, the trunk volume of the tree, the smaller the crown-fullness ratio, therefore, the relation of the diameter, height, trunk volume of the tree and the crown-fullness ratio is in negative relation. The relation of the form factor and the crown-fullness ratio is in positive relation.
分 类 号:S758[农业科学—森林经理学]
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