Abstract

PEREZ-PAREDES, María Guadalupe; SANCHEZ-GONZALEZ, Arturo  and  TEJERO-DIEZ, José Daniel. Population structure and habitat traits of two Cyatheaceae species of Hidalgo state, Mexico. Bot. sci [online]. 2014, vol.92, n.2, pp.259-271. ISSN 2007-4476.

The tree ferns (Cyatheaceae) are a conspicuous component of the humid montane forest in the tropical and subtropical regions of the world. In Mexico, the tree ferns distribution is limited almost entirely to the humid montane forest (cloud forest). Although some species are included in the Norma Oficial Mexicana (governmental regulations normalized) and international red lists, there is no information on the current status of their populations. Two species widely distributed within the montane rainforest, and classified as "subject to special protection" under Mexican law, are Alsophila firma and Cyathea fulva. In the present study, basic data was collected about the structure, population density and habitat characteristics of these tree ferns, in order to determine to what extent the current state of their habitat threatens their survival. We found that populations of both species are normal or dynamic, with high regeneration potential, forming part of the sub-canopy at sites with high tree cover, making them tolerant to shade. The variables that best explained differences in population density for A. firma were elevation, slope, presence of roads, and ground cover, while for C. fulva it was canopy cover. The establishment and survival of populations of both species depends heavily from conservation of their habitat (humid montane forest) because they require a high percentage of vegetation cover.

Keywords : Alsophila firma; Cyathea fulva; extinction risk; humid forest; size structure.