濒危植物夏蜡梅3种林型的群落特征比较OA

To reveal the habitat adaptation mechanisms of Calycanthus chinensis in different vegetation types,this study selected three typical forest types—deciduous evergreen broadleaf mixed forest(abbreviated as mixed forest),Chinese fir(Cunninghamia lanceolata)forest,and Moso bamboo(Phyllostachys edulis)forest—in Tiantai County,Zhejiang Province for community investigation.The quadrat sampling method was employed to survey the tree,shrub,and herb layers,and the community composition,species diversity,and stand structure were characterized.The results showed that a total of 231 vascular plant species were recorded across the three stand types,with species richness ranked as mixed forest>Moso bamboo forest>Chinese fir forest.Significant differences in species composition were detected among stand types(P=0.001).Stand structural analyses revealed that the density of woody plants both in mixed and Chinese fir forests exhibited a"J"-shaped distribution pattern of with increases in diameter and tree height,whereas it presented an inverse"J"-shaped pattern in the Moso bamboo forest.The population structure of Calycanthus chinensis showed a discontinuous(multi-peaked)distribution pattern.The Shannon-Wiener and Pielou indices of the tree layer followed the trend of mixed forest>Chinese fir forest>Moso bamboo forest.Furthermore,the multiple diversity indices of the tree and shrub layers in the mixed forest had significantly positive correlations with the growth indicators of Calycanthus chinensis(P<0.05),whereas the density of Moso bamboo individuals showed a significant(0.01≤P<0.05)or extremely significant(P<0.001)negative correlation with the growth of Calycanthus chinensis.These findings suggest that mixed forests and Moso bamboo forests should be prioritized as core habitats for Calycanthus chinensis population recovery.Ecological management should focus on enhancing tree and shrub layer diversity in mixed forests and implementing moderate thinning in Moso bamboo forests to create suitable growth conditions of Calycanthus chinensis populations.