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该文研究了北京西山地区针叶林林窗的形成方式及其特征 .结果表明 :在西山人工针叶林中 ,林窗形成最主要的方式为人为砍伐 ,占 76 7% ;其次是由病虫害和干旱形成的 .林窗以 10～ 2 0m2 所占的面积比例最大 ,为2 7 93 % ,而以 <10m2 所占的数量最多 ,占 46 5 1% .在扩展林窗中 ,以 2 0～ 40m2 的数量和面积比例最大 ,为5 1 12 %和 45 45 % .林窗主要由一株形成木形成 .在所调查的林分中平均每个林窗拥有的形成木数为 1 79株 ,每株形成木所能形成的林窗面积为 9 0 1m2 ,扩展林窗面积为 16 2 1m2 .林窗大部分是在 10年前形成的 .
This paper studied the formation and characteristics of coniferous forest gap in Xishan Mountain, Beijing.The results showed that the dominant form of forest gap was man-made felling in the artificial forest of Xishan Mountain, accounting for 76.7%, followed by pest and drought The area of 10-20 m 2 was the largest, accounting for 2 7 93% of the total area of the forest gap, accounting for 46 5 1% of the total area of <10 m 2. In the expansion gap, with the number of 20-40 m 2 And the area ratio was the highest, which was 51.2% and 45.45%, respectively.It mainly consisted of one forming wood.The average number of forming woods per forest gap in the investigated forest was 1 79. Each plant formed The area of gully that can be formed by wood is 9 0 1m2, and the area of gully is expanded is 16 2 1m2. Most of the gully is formed 10 years ago.