浙江丽水白云山红豆树人工林的径级结构和空间分布格局

Size class structure and spatial distribution pattern of Ormosia hosiei plantation in Baiyun Mountain, Lishui

关键词:  红豆树, 群落结构, 径级结构, 格局分析, 空间分布格局

Key words:  Ormosia hosiei, community structure, size class structure, pattern analysis, patial distribution pattern

摘要:

采用固定样地调查的方法,在浙江丽水白云山林场的红豆树人工林中共建立两个20 m × 40 m的监测样地(1号样地和2号样地),并进行群落调查。结果表明:(1)共记录到乔木和灌木物种13种,优势种主要为红豆树、深山含笑(Michelia maudiae)和刨花楠(Machilus pauhoi)等。两个样地的径级结构均成倒“J”分布。(2)从空间分布看,两个样地的红豆树均基本呈现随机分布。在较小空间尺度上,1号样地和2号样地的其他树种与红豆树之间均呈负相关,特别是1号样地。(3)通过分析环境因子对红豆树胸径生长的影响,发现样地内除土壤厚度外,其他因子如全氮、全磷含量、pH值及凋落物等对红豆树的生长影响不大。研究认为:① 白云山的红豆树人工林尚具有较大的生长潜力。② 红豆树的种内竞争可较小,而红豆树和其他树种之间则可能存在较强的种间竞争。③ 后期管理过程中,该类林分可以适当伐除其他树种,并对大红豆树进行修枝,即有利于干形也可促进小红豆树的生长,同时加强对土壤厚度的管理。通过对40年生红豆树成熟人工林的径级结构和空间分布格局的研究,可以更好地了解林分结构特征和物种更新过程。

Abstract:

We set up two 20 m × 40 m plots(Plot 1 and Plot 2)using forest dynamics plot investigation protocol in Ormosia hosiei plantations of Baiyuan Mountain, and conducted a community survey in these two plots. The results were as follows:(1)Thirteen tree and shrub species were recorded, of which the dominant species were Ormosia hosiei, Michelia maudiae and Machilus pauhoi. Stem size class structures of both plots were reverse “J” shaped.(2)Stems of Ormosia hosiei in both plots were spatially randomly distributed. At the small spatial scales, O. hosiei and other species were negatively correlated in both plots, especially in Plot 1.(3)Analysis of soil effects on the DBH growth of O. hosiei only showed a significant effect of soil layer thickness, but not significant effects of total phosphorous content, total nitrogen content, soil pH and litter. The results suggest: ① The Ormosia hosiei plantations were with large growth potentials. ② The intraspecific competition between O. hosiei stems may be weak, while the interspecific competition between O. hosiei and other species may be strong. ③ For the management of these O. hosiei plantations, it might be appropriate to remove some branches of large stems to facilitate the growth of small stems, and to enhance the management of soil layer thickness. Through the study on size class structure and spatial distribution pattern of 40 years mature O. hosiei plantation, we can better understand the update process and structure characteristics, and it provides more scientific basis for artificial afforestation, plantation large size materials and ational management.