不同恢复年限红锥人工林群落结构特征及经营策略

Community structure characteristics and management strategies of Castanopsis hystrix plantation with different restoration years

采用空间代替时间的方法,以南亚热带红锥人工林不同恢复年限(6、10、15、20、25、30和34 a)林分为对象,研究了红锥人工林林分物种组成和结构在不同恢复年限下的变化特征。结果表明多度、丰富度及材积在不同林龄阶段的分布差异较大。不同林龄阶段的林分组成和结构差异显著,随着林龄的增加,多样性指数和丰富度指数均呈先增加后降低的趋势。不同年龄阶段的树种胸径分布格局变化较大,30 a集中分布胸径>20 cm的树木。红锥人工林林近熟阶段(30~34 a)乔木株数较少,但是从林分的生产力来说,却提供了50%以上的林分蓄积。综上,不同林龄阶段的人工林经营策略需要考虑林分自然生长规律和关键树种竞争机制,使少量优质林木个体留给自然演替进程控制和调节,实现人工林生产力提升和结构功能的生态合理性和经济有效性。

In this study,we selected Castanopsis hystrix plantations with age series of 6,10,15,20,25,30 and 34 years located at Longyandong Forest Farm in Guangdong Province to analyze the variation trend ofαdiversity indexes of tree species with different restoration years by adopting the method of spatial instead of time.The results showed that the distribution of abundance,richness and timber volume were significantly different at different age stages.The stand composition and structure were significantly different at different age stages,and with the increase of stand age,the diversity index and richness index were firstly increased and then decreased.The distribution pattern of DBH of tree species at different age stages changed greatly,and trees of DBH>20 cm was concentrated at 30 years.In the near mature stage(30-34 a),the number of trees in the plantation was less,but it provided more than 50%of the stand volume in terms of stand productivity.We concluded that the management strategy of plantation at different age stages should consider the natural growth law of stand and the competition mechanism of key tree species,so that a few individuals of high quality trees should be left for the control and regulation of natural succession process,so as to realize the ecological rationality and economic effectiveness of the productivity improvement and structure function of plantation.