研究了云南碧塔海两块亚高山云冷杉 ( Picea -Abies)林内中小尺度林窗的干扰体系,结果表明: 林窗和扩展林窗分别占林地面积的 19% 和 41% ,平均面积为 44 m2和 139 m2 ,林窗的形成频率为 0. 005～0. 007 /y。估计平均林窗周期为 167年。大多数林窗(占 87% )的制造林窗树木( gap-maker,简记为 GM )为 1个以上,平均每个林窗的 GM为 2. 9个,同一林窗内的 GM常常死于不同的时间。在所有调查的 GM中,折断占 60% ,而根拔和直立死亡分别为 28% 和 12% 。
 

The disturbance regime of small and middle scale gap in two stands of a subalpine old-growth Picea-Abies ( spruce-fir) forest around Bitahai Lake, north-west corner of Yunnan Province, were examined. Canopy gaps and expanded gaps covered 19% and 41% of total land area. The mean area of gaps and expanded gaps were 44 m² and 139 m2 respectively. The gaps were formed with a frequency of 0. 005 to 0. 007 per year, and the estimated m ean gap return interval was 167 years. Most gaps ( 87% ) had more than one gap-maker ( overall means: 2. 9 gap-makers per gap) , and gap-makers within a gap were often from mortality events in separated time. In all gap-makers investigated snap were 60% , but uproot and died standing were 28% and 12% respectively.