Epiphyte assemblages respond to host life-form independently of variation in microclimate in lower montane cloud forest in Panama
Sanger, JC and Kirkpatrick, JB, Epiphyte assemblages respond to host life-form independently of variation in microclimate in lower montane cloud forest in Panama, Journal of Tropical Ecology, 30, (6) pp. 625-628. ISSN 0266-4674 (2014) [Refereed Article]
We investigated the effects of host tree on epiphyte diversity, controlling for microclimate. We measured the
light profiles of the lower trunks of 20 individuals, each from three host groups (tree ferns, dicots, palms) occupying
the understorey in a tropical montane forest in Panama. The per cent cover and species richness of vascular and nonvascular
epiphytes were surveyed on the lower trunks of each understorey host. Light varied considerably between
trees (5–21% total transmitted light) but mean light level did not vary between types of host. Light was not significant
as a covariate with host in any model. Tree ferns had higher covers than dicots and palms of filmy ferns (15%, 0.02%
and 0.2%), other ferns (7%, 0% and 0.5%) and other vascular epiphytes (16%, 3% and 3.4%), and greater species
richness of vascular epiphytes (filmy ferns: 3, 0.4 and 0.5; other ferns: 2, 0.2 and 0; other vascular: 7, 2 and 2).
Dicots had a higher cover of liverworts (53%) than palms (18%) and tree ferns (27%). Palms and tree ferns were the
compositional extremes. We conclude that the differences in species composition and cover between the three host
groups relate better to physical differences between hosts than differences in light climate.
bryophytes, community assembly, dicots, host preference, light environment, palms, Panama, tree ferns, vascular epiphytes