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长白山暗针叶林实际林隙面积大多小于 80m2 ,扩展林隙面积主要集中在 5 0m2 ～ 2 0 0m2 之间(75 %左右 ) ;随着海拔高度增加 ,平均林隙面积变小 ,每公顷林隙数量有增加的趋势。长白山暗针叶林林隙形成的类型主要是掘根风倒、干基折断和掘根风倒形成的 ,分别占 3 4 %和 3 0 .6%。风干扰是长白山暗针叶林维持和发展的重要因素。暗针叶林每个林隙内林隙形成木的数量以 2株～ 3株居多 ,共占林隙总数的 61 % ;并且每个林隙内林隙形成木的数量随海拔高度增加呈现减少趋势。林隙形成木主要由云杉、冷杉等树种组成 ,其中云杉所占比例为 62 % ;长白山暗针叶林林隙形成木分布最多的径级是 2 0cm～ 4 0cm ,占林隙形成木总数的 61 % ,云杉在暗针叶林的林隙形成中起主导作用。长白山暗针叶林各个时期林隙形成的速度不是均等的。
The actual gap area of dark coniferous forest in Changbai Mountain is mostly less than 80m2, and the area of expanding gap mainly concentrates between 500m2 ~ 200m2 (about 75%). As the altitude increases, the average gap area becomes smaller, The number of gaps tends to increase. The main types of gap formation in the dark coniferous forest of Changbai Mountains were dugout, dry-base breakage and dug-down, which accounted for 34% and 30.6% respectively. Wind disturbance is an important factor in the maintenance and development of dark coniferous forest in Changbai Mountain. The number of wood-forming woods in each gap of dark coniferous forest was mostly 2 to 3, accounting for 61% of the total number of gaps in the gaps. The number of wood-forming woods in each gap decreased with increasing altitude trend. The gap-forming wood is mainly composed of spruce, fir and other tree species, of which the proportion of spruce accounts for 62%; Changbai Mountains dark coniferous forest gap formation wood distribution is the most diameter class 20cm ~ 40cm, accounting for the total number of gap formation wood 61%, spruce plays a leading role in the formation of gaps in dark coniferous forest. Changbai Mountain dark coniferous forest gap formation rate is not equal in all periods.