桂西北常绿混交林林隙形成原因与分析

Causes and Analysis of Gap Formation of Evergreen Mixed Forest in Northwest Guangxi

[目的]探究林隙形成的原因。[方法]以广西环江县常绿混交林为研究对象进行分析。[结果]已鉴定出的形成木种类有79种,占比71.2%。林隙形成的方式为翻蔸、干中折断、干基折断及枯立,其中翻蔸、干中折断为主要形式。不同径级林隙形成木的死亡方式以15~30 cm径级为主,小径级占比最少,大径级的树木受灾后比小径级的容易形成林隙。[结论]林隙边缘木受冰冻灾害受损形成林隙比例比林内高。冰冻灾害及大冠幅是形成林隙的主要原因。

[Objective]To explore the causes of forest gap formation.[Method]The evergreen mixed forest in Huanjiang county,Guangxi was analyzed as the research object.[Result]79 species of cambium species have been identified,accounting for 71.2%.The forms of forest gap formation were turning stump,breaking in dry,breaking in dry base and standing dry,among which turning stump and breaking in dry are the main forms.The death mode of gap forming trees in different diameter classes was mainly 15~30 cm diameter class,and the proportion of small diameter class was the least.Trees with large diameter class were easier to form forest gaps than those with small diameter class.[Conclusion]The proportion of gap formation is higher than that in the forest.Freezing disaster and large crown width are the main reasons for the formation of forest gap.