抚育间伐对冀北山地蒙古栎林分结构的影响

Effect of thinning on the structure of Quercus mongolica forest in mountain area of northern Hebei Province

为了解抚育间伐对蒙古栎林结构特征的影响,以塞罕坝机械林场的蒙古栎林为研究对象,研究了抚育间伐对林分的直径分布、树高分布以及空间分布格局的影响。研究结果表明,抚育间伐前后林木直径和树高分布均服从于Weibull分布,间伐后小径级林木所占比例明显减小,中大径级比例明显增加;抚育间伐前后,蒙古栎林在多数尺度上都表现为集群分布,但抚育间伐后其聚集程度明显下降;取样大小对蒙古栎的空间分布格局具有明显影响,随取样面积的增大,蒙古栎林的聚集程度逐渐下降,逐渐向随机分布转化。综上,抚育间伐使蒙古栎林的林分状况得到了明显改善,结构趋于合理。

In order to understand the effects of thinning on the structural characteristics of Quercus mongolica forests,the effects of tending on the diameter distribution,tree height distribution and spatial distribution pattern of the Q.mongolica were studied in Saihanba Mechanized Forestry Farm.The results of the study showed that the distribution of tree diameter and tree height before and after thinning were close to the Weibull distribution.After thinning,the proportion of small-diameter trees decreased significantly,and the proportion of medium-large diameter trees increased significantly.Before and after thinning,Q.mongolica forest showed aggregation distribution on most scales,but its aggregation degree decreased significantly after thinning.Sampling size had a significant impact on the spatial distribution pattern of Q.mongolica forest.With the increase of sampling area,the aggregation degree of Q.mongolica forest gradually decreases and gradually transforms to random distribution.In conclusion,thinning had significantly improved the status of the Q.mongolica and its structure had become more reasonable.