Vascular epiphytic flora of a high montane environment of Brazilian Atlantic Forest: composition and floristic relationships with other ombrophilous forests

ABSTRACT Only a few studies regarding vascular epiphytes have been conducted in mixed ombrophilous forests (MOF) in Serra da Mantiqueira, a mountainous environment in the Brazilian Atlantic Forest, where the relationships of epiphytic flora with other physiognomies are unknown. This study aimed to survey the epiphytes of a MOF remnant located in Serra da Mantiqueira, and to analyze the floristic relationships with ombrophilous forests of the Southern and Southeastern regions of Brazil. The checklist was compared with 51 other areas composed of ombrophilous forests and/or ecotones with other physiognomies using UPGMA (with Sørensen index), and canonical correspondence analysis (CCA). We recorded 138 species, and Orchidaceae and Polypodiaceae were the richest families (51 and 23 species, respectively). The UPGMA showed the importance of physiognomy and elevation in the floristic relationships, and CCA reinforced the influence of elevation, in addition to the shortest distance to the ocean and minimum annual temperature; however, in this analysis, the physiognomies showed little influence on the relationships. The epiphytic flora of MOF of Southern and Southeastern regions of Brazil has different relationships compared with the data available for shrubs and trees, suggesting a greater importance of phorophytic species than geographical distance and, to some extent, environmental variables.

摘要：针对巴西大西洋森林山地环境曼蒂凯拉山脉（Serra da Mantiqueira）内的混合云雾林（mixed ombrophilous forests, MOF），现有维管附生植物相关研究寥寥无几，且附生植物区系与其他植被型之间的关联尚不明确。本研究旨在调查曼蒂凯拉山脉内一处混合云雾林遗存中的附生植物类群，并分析其与巴西南部及东南部地区云雾林的区系关联。本研究将该区域的附生植物物种名录与其余51处由云雾林及/或与其他植被型构成的生态交错带组成的研究区域进行对比，采用非加权组平均法（UPGMA，结合索伦森指数（Sørensen index））与典范对应分析（canonical correspondence analysis, CCA）开展分析。本研究共记录到138种附生植物，其中兰科（Orchidaceae）与水龙骨科（Polypodiaceae）为物种丰富度最高的类群，分别包含51种与23种。UPGMA分析结果表明，植被型与海拔在区系关联中发挥着重要作用；CCA分析则进一步证实了海拔的影响，此外距海洋的最短距离与年最低温同样具有显著影响，但该分析中植被型对区系关联的影响较弱。巴西南部及东南部地区混合云雾林的附生植物区系与现有灌木、乔木的相关研究结果存在差异，这提示附生植物的宿主物种较地理距离乃至部分环境变量，对附生植物区系的塑造作用更为显著。