<p><strong>Niche Breadth and Overlap of <em>Sphagnum </em>Species in Costa Rica</strong></p>

Abstract

Abstract. Niche breadth and overlap values of Sphagnum species in Costa Rica are similar to those reported for Sphagnum-dominated peatlands in North America. Sphagnum magellanicum Brid. and S. sparsum Hampe have the broadest niche breadth of the common species in Costa Rica. Although S. sancto-josephense Crum & Crosby has a relatively narrow niche breadth, it is one of the most common species along with S. magellancium and S. sparsum in the Sphagnum habitats of Costa Rica. Niche overlap is high among species with the exception of S. platyphyllum (Braithw.) Warnst. which is found in habitats that are rich in iron. The pH, conductivity, and concentrations of Ca, Fe, Mg, Mn, Na, K, and P of Sphagnum habitats in Costa Rica are similar to those reported for páramo habitats in South America.

<p><strong>Niche Diversification of <em>Sphagnum </em>in Bolivia</strong></p>

“…The mean niche overlap for all species in Bolivia is 0.83. These values are higher than those reported by McQueen (1995) for species in Costa Rica that have a mean niche overlap of 0.63. These comparisons are meaningful since the resources examined and the number of classes for the parameters were the same with the exception of Fe and Mn that were not used for the study of species in Bolivia.…”

“…McQueen (1991) reported a pH range of 4.0 to 6.4 for the Sphagnum-dominated páramo habitats of in Ecuador and Cleef (1981) gave a pH range of 4.6 to 5.3 for similar habitats in Colombia. Sphagnum habitats in Costa Rica are more acidic with a pH range of 3.0-5.2 (McQueen 1989(McQueen , 1995. The occupation by Sphagnum species of the parameters examined in this study in Bolivia differs from that in other regions that have been examined.…”

“…The purpose of this study was to examine the niche breadth and overlap of Sphagnum species in Bolivia. Based on examination of herbarium specimens and field observations in Bolivia, Sphagnum species are found between elevations of 1800 and 4200 m. As in other regions of Central and South America, the majority of species are found in the páramo and cloud forests of the Andes (McQueen 1991(McQueen , 1995. Preliminary field observations in Bolivia suggested that Sphagnum does not form extensive mats or peatlands such as those found in the northern Andes; however, species diversity in Sphagnum habitats of Bolivia appear to be greater.…”

“…Niche values for Sphagnum species in the northern Andes and Central America are similar to those reported for peatlands in North America. McQueen (1995) reported that niche values for species in Costa Rica were more similar to those of North America than those of South America. This may be due to a greater diversity of species in the northern Andes and Central America.…”

“…This was attributed to the low species diversity of the peatlands examined. McQueen (1995) suggests that species farther south in the Andes would have greater niche values than in the more species rich and diverse habitats farther to the north.…”