不同林龄阶段马尾松人工林群落结构特征及经营策略

Community Structure at Different Age Stages and Optimization Management Strategies in a Masson Pine Plantation

采用空间变化代替时间变化的方法,以南亚热带马尾松人工林不同年龄阶段（10、20、30、40、50a和60a）林分为对象,研究了马尾松人工林林分物种组成和结构的变化特征。结果表明,多度、丰富度及材积在不同年龄阶段的分布差异较大：1）不同年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;2）不同年龄阶段的树种胸径分布格局变化较大,60a集中分布胸径〉20cm的林木;3）马尾松近熟阶段（50-60a）林木株数较少,但是从林分的生产力来说,却提供了50%以上的林分蓄积。提出不同年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。

By the method of substituting temporal serial with spatial serial, and taking six forest lands with different ages （10, 20, 30, 40, 50 and 60 years） in monoculture region as objects, this paper studied the change characteristics of species composition and structural differences of the stands with different ages. The results showed that, 1） Differences in species composition and structure of the stands with different ages were significant, species richness and abundance index increased firstly and then decreased with the increase of ages; 2） Tree diameter distribution showed significant differences among different stand layers. Tree individuals with diameter more than 20 cm dominated at the late age stages; 3） Stand volume presen- ted great variance along the age stages. Si vicultural practices play an important role in shaping the age stage dynamics of Masson plantation, resulting in differences in the structure of the community. We at-tempt to integrate the structural and functional characteristics of monoculture as a way to enhance our ability both to predict and manage monoculture forest due to their increasing importance as timber sources, providers of environmental services, and management purpose. Further research is needed to gain a better management strategy linked with forest succession.