浙江中部地区公益林的群落结构

Community structure of a public service forest in central Zhejiang Province

采用两阶抽样法选取517个公益林固定小班监测样地,对浙江省中部地区公益林主要群落(马尾松Pinus massoniana林、杉木Cunninghamia lanceolata林、针阔混交林、阔叶林、毛竹Phyllostachys edulis林和灌木林等6种公益林群落)进行群落组成、结构特征的研究,并通过编制主要优势种群的静态生命表,揭示群落建群种在群落构建过程中的生命特征。结果表明:总体上公益林物种组成丰富,乔灌草3个层分别由52科103属263种,59科125属449种和36科56属286种植物组成,其中乔木层的优势种群为马尾松,杉木,木荷Schima superba,青冈Cyclobalanopsis glauca,毛竹,杨梅Myrica rubra等;但由于破坏性利用,各公益林群落在径级结构上趋势一致,均呈现逆"J"型结构,随着胸径的增大,乔木树种数量的比例逐渐减小;此外,群落构建变化中的环境阻力的大小是影响建群种死亡率的关键因素,不同演替阶段的优势种群在不同龄级的环境阻力各不相同,其中演替后期优势种青冈在龄级增长过程中死亡率随环境阻力的降低而持续减小,生命期望在后期达到最大,因此,对现阶段的演替后期优势种群的抚育,对改造和提升阔叶林的质量,加速群落正向演替尤为重要。

To reveal the vital signs of constructive species in the community development process, a static life table of the dominant population was produced based on a two-stage sampling method of 517 public service forest plots. Community composition and structural characteristics for six types of forests and bamboo stands： 1） pine, 2） fir, 3） broadleaf, 4） mixed coniferous and broadleaf, 5） moso bamboo, and 6） scrub growth forests were selected in central Zhejiang Province. Results showed 263 species of trees belonging to 103 genera in 52 families, 449 species of shrubs in 125 genera of 59 families, and 286 species of herbs from 56 genera in 36 families. Dominant tree and bamboo populations were Pimts massoniana, Cunninghamia lanceola- ta, Schima superba, Cyclobalanopsis glauca, PhyUostachys edulis, and Myrica rubra. Forest communities all had an inverse ＂J＂ horizontal structure, and the number of tree species gradually decreased than others with an increase in DBH. The dominant species like C. glauca, in late successional stages, continuously declined when there was a reduction in environmental resistance with life expectancy. Therefore, maintaining succession late dominant population at the present stage of succession would be particularly important for transforming and upgrading the quality of a broadleaf forest and accelerating positive community succession.