Abstract Detail

Pteridological Section/AFS

Moran, Robbin [1], Trujillo, David [2], Perez, Alvaro [2], Salazar, Laura [2], Aviles, Diana [2], Navarrete, Hugo [2].

Low-trunk Epiphytic Ferns on Tree Ferns versus Angiosperms in Northwestern Ecuador.

We compared the occurrence of epiphytic ferns on the lower trunks of tree ferns versus angiosperms. The study was carried out at four sites: the Rio Palenque Science Center (200 m), Maquipucuna Cloud Forest Reserve (1200 m), Rio Guajalito Biological Station (1800 m), and the Guandera Reserve (3300 m). At each site, 30 tree fern trunks with a root mantle were sampled for fern epiphytes up to a height of 3 m, and the same was done for the nearest angiosperm trunk of similar diameter at breast height (at Río Palenque, however, only 15 pairs of tree ferns and angiosperms were found). For the study sites combined, we found a total of 122 species of epiphytic ferns, of which 59(48%) occurred frequently enough to be tested statistically whether they occurred more frequently on tree ferns versus angiosperms. None of the epiphytic species occurred more frequently on angiosperms; however, 19 (33% of those statistically testable) occurred more frequently on tree ferns, and of these, 6 (10% of those statistically testable) were entirely restricted to tree ferns. Tree ferns also harbored a significantly higher number of epiphytic species, averaging 1.7--7 (depending on the site), whereas angiosperms averaged 0.5--4. The middle elevation sites (Maquipucuna and Rio Guajalito) had the greatest number of species. No correlation was found, for either tree ferns or angiosperms, between diameter at breast height and number of epiphytic species. In conclusion, low-trunk fern epiphytes exhibited significant differences on tree ferns versus angiosperms in regards to species composition and number of species per trunk. These differences are probably caused by the root mantles providing more favorable microhabitats for the establishment of fern prothalli and a better substrate for the attachment of fern sporophytes.

1 - New York Botanical Garden, Institute of Systematic Botany, 200th St & Kazimiroff Blvd, Bronx, New York, 10458, USA
2 - Pontifica Universidad Catolica Ecuatoriana, Departmento de Botanica, Apdo. 17-01-2184, Quito, , Ecuador

Keywords:
epiphytes
ferns
neotropics
Ecology.

Presentation Type: Paper
Session: 22-1
Location: Superior B (Cliff Lodge)
Date: Monday, August 2nd, 2004
Time: 2:00 PM
Abstract ID:175