Chilpa et al. 2012 (Conference Paper) Mexico

Fractals in the Canopy, a look at the settlement of Epiphytic Bromeliads in a dry forest.

Author(s):—N. Chilpa G., M. Tamayo C., J.L. Andrade & C. Reyes G.

Publication:— (2012).

Abstract:—The distribution of epiphytic bromeliads can be determined by the structural characteristics of the different host trees and the complex mosaic of microhabitats of canopy that may favor establishment and growth. The vertical stratification is the result of microclimatic variation (radiation and water availability) from the top of the canopy to the forest interior. Our goals were to determine the horizontal distribution, vertical stratification and abundance of epiphytic bromeliads in phorophytes, as well as the meso-environmental variation among sites close to a cenote (permanent water source) and micro-environmental variation among two phorophytes and between three vertical canopy strata in a deciduous forest of the Yucatan Peninsula. Eleven 10 x 10 m plots were established, and all trees and epiphytic bromeliads within them were surveyed. Tree traits such as diameter, canopy volume and height were determined. We measured the distance of the plots close and far from the cenote. Photosynthetic photon flux density, temperature and humidity were measured in three strata of two phorophyte species during the wet and dry seasons. The dominant species was Tillandsia brachycaulos (77% of all epiphytic bromeliads). Bromeliads were more abundant around the mid-upper trunk (zone IIb, 33% of bromeliads) and the start of the canopy (III, 25.2% of bromeliads) of host trees. Epiphytic bromeliad density decreased as the plots became more distant from the cenote, while the tree identity was less important, even though these presented significant differences in microclimate. Epiphytic bromeliad density decreased as the plots became more distant from the cenote, while the tree identity was less important, even though these presented significant differences in micro-environment. There is a vertical stratification of epiphytic bromeliads, with most species in the middle section, which can be linked to light and VPD being less stressful, particularly in the dry season.