栓皮栎植冠的构型分析

对栓皮栎（Ｑｕｅｒｃｕｓ　ｖａｒｉａｌｉｌｉｓ ＢＬ．）个体发育中不同阶段的植冠构型进行统计分析，结果发现：构型转变主 要表现在分枝格局上，除枝倾角保持稳定外，分枝率、枝间距和叶倾角都发生过显著改变。不同阶段构型 分析的比较表明：１）幼苗阶段，高生长不明显，分枝率低，枝间距较小；２）幼树阶段，高生长和冠幅扩展迅 速，分枝率和叶倾角都较大，枝倾角无明显变化；３）成树阶段，冠幅扩展明显放慢，高生长减缓，分枝率、叶 倾角明显低于幼树阶段，枝倾角仍无明显变化。

Architectural analysis of crown geometry in Quercus variabilis

Architectural analysis were made in different development stages of Quercus uariabilis BL. The result is that architectural transition, mainly characteried by the changes of branch pattern, and bifurcation ratio, interval between branch,and leaf angle to horizon, varied signficantly, but branch angle to horizon kept stably in different development stage. The architectural comparison shows that: 1) In seeding stage, trees grew slack, bifurcation ratio and interval between branch were smaller; 2)in sapling stage, saplings grew quickly and crown enlarged rapidly, hath bifurcation ratio and leaf angle to horizon were larger than those in seeding stage, branch angle to horizon still didn' t vary obviously; 3 ) in mature tree stage, crown' s, expansion and trees' growth slowed down, both bifurcation ration and leaf angle to horizon were smaller than those in sapling stage, branch angle to horizon was still stable.