Epiphytic Communities of Bryophytes and Macrolichens in a Costa Rican Montane Oak Forest

Abstract

Because of their complexity and variety of microhabitats, lowland and montane tropical rain forests are the habitat of many bryophytes and lichens. Most of the bryophytes and lichens of tropical rain forests are epiphytes. Even though they are often small and inconspicuous, bryophytes and lichens are an important component of tropical forest ecosystems, especially montane ones, in terms of ecosystem functioning, biomass and biodiversity (Pocs 1980, 1982; Veneklaas and Van Ek 1990; Veneklaas et al. 1990; Hofstede et al. 1993; Wolf 1993; Clark et al. 1998a, b, Chap. 6). Whereas increasing attention has been paid to the taxonomy and diversity of tropical bryophytes and lichens, little is known about their ecology and the impacts of deforestation on these communities. Relevant aspects are degradation of biomass, loss of species diversity, and change in microclimate associated with forest destruction and fragmentation. Deforestation is generally considered to have a deleterious effect on the bryophyte flora of the primary forest, and may lead to a considerable loss of species. Therefore, analyses of epiphytic cryptogam communities should be considered a research priority for conserving biodiversity and ecosystem functions. The present book chapter summarizes recent research on the cryptogamic vegetation of the upper montane oak forests of the Cordillera de Talamanca, Costa Rica (Holz 2003).Aspects dealt with in this chapter are the diversity and biogeography of bryophytes, the distribution patterns of life forms and species in microhabitats and along ecological gradients, the host preference and community composition of epiphytic bryophytes and macrolichens, and the secondary succession of the epiphytic cryptogam vegetation.