Natural Regeneration in a Conservation Unit: Subsidy for Restoration Actions

ABSTRACT In order to evaluate the regeneration of a forest remnant, we installed 256 2 x 2 m plots for measuring forest species individuals with height ≥ 30 cm and stem diameter ≤ 1 cm. Horizontal structure was evaluated and calculated by the Shannon (H') diversity index and the Pielou (J) evenness index. We performed clustering analysis by the agglomerative and divisive hierarchical method (the variable was the number of individuals); and used the Principal Component Analysis to verify the species distribution. We sampled 3021 individuals, distributed in 26 families and 51 species (H' = 2.78 and J = 0.66). Allophylus edulis had the highest values of absolute frequency (63.3) and absolute density (5186 ind.ha-1), while Ligustrum lucidum presented greater dissimilarity. The analysis showed the presence of regeneration mechanisms, and evidenced biological invasion problem.

摘要：为评估残存森林的更新状况，本研究布设256个2米×2米样地，用于调查株高≥30厘米、茎直径≤1厘米的林木个体。通过香农（Shannon）多样性指数（H'）与皮卢（Pielou）均匀度指数（J）对群落水平结构开展评估与量化计算。本研究以个体数量为变量，采用聚合-分裂分层聚类法进行聚类分析，并通过主成分分析（Principal Component Analysis）验证物种分布格局。本次调查共记录3021个植物个体，隶属于26科51个物种，香农多样性指数为2.78，皮卢均匀度指数为0.66。异木患（Allophylus edulis）的绝对频度（63.3）与绝对密度（5186 株·公顷⁻¹）均为最高，而女贞（Ligustrum lucidum）则呈现出更高的物种组成差异度。分析结果表明研究区域存在森林更新机制，同时证实了生物入侵问题的存在。