彭州人工马尾松林林隙干扰特征

本文对彭州人工马尾松(Pinus massoniana)林林隙的一般特征和干扰状况进行了初步研究.共设置三条样线总长3.5km,调查到82个林隙.结果表明:75.61%的冠林隙(CG)分布在20-80m2之间,其中以40-60m2所占面积比例最大,为23.00%;扩展林隙(EG)大小多在60-200m2之间,占87.80%,其中150-200m2所占面积比例最大,为28.74%.林隙的线状密度为23.42个.km-1.不同调查样点林隙的分布格局不同.林隙形成最主要的方式为人为砍伐,比例高达71.46%.林隙的形成木主要是马尾松,占81.29%.林隙形成木的径级主要介于10-25 cm之间,各林隙的形成木在不同径级中株数分配比例不同.65.84%的林隙是由2-5株形成木所形成,平均每个林隙的形成木为5.09株,每株形成木所能形成CG的面积为10.02m2,EG的面积为25.53m2.

Distubance Characteristics of Gap in Artificial Pinus massoniana Forest in Pengzhou, Sichuan Province

The general characteristics and disturbance regime in artificial Pinus massoniana forest in Pengzhou were studied.3 sampling lines were set whose total length was 3.5km,and 82 gaps were investigated.The results indicte that 75.61% of canopy gaps(CG) distributes from 20m~2 to 80m~2,of which the gaps of 40m~2 to 60m~2 occupy the highest percentage in size,which is 23.00%;87.80% of the expanded gaps(EG) distributes from 100 m~2 to 150m~2,of which the gaps of 150 m~2 to 200 m~2 occupy the highest percentage in size,28.74% of the total.The linear density of gaps is 23.42 km~(-1).The gap distribution patterns are different in different samplings.71.46% of the types of the gap formation is human cutting,which is the main type.Major gap makers in the forest are Pinus massoniana,occupied 81.29% of the total.The diameters of most gap makers range from 10cm to 25cm,and there are different numbers of gap makers in different diameters.65.84% of the total gaps is formed by 2 to 5 gap makers,with an average 5.09 trees per gap.The size of CG and EG formed by one gap maker is 10.02 m~2 and 25.53m~2 respectively.