Diversity and Ecology of Bryophytes and Macrolichens in Primary and Secondary Montane Quercus Forests, Cordillera de Talamanca, Costa Rica

Aspects dealt with in this study 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, the secondary succession of epiphytic vegetation and the selection of indicator species. For the first time recovery of epiphytic cryptogam communities in secondary tropical montane forests receives full attention. The study took place in the upper Río Savegre watershed area on the Pacific-facing slope of the western Talamanca Mountain Range, Costa Rica.In Chapter 1 a general introduction to tropical montane rain forests and to bryophytes and macrolichens as an important component of these ecosystems is presented. The reader is introduced to the study area, its climate, geology and vegetation. In Chapter 2 the phytogeographical patterns of bryophytes of Costa Rica's Talamancan montane oak forests are analysed and discussed.Chapter 3 deals with bryophyte diversity, microhabitat differentiation and distribution of live forms in an Costa Rican upper montane Quercus forest. It gives a comprehensive overview on the bryophyte flora of all microhabitats, including forest floor and the understorey of the forest.Chapter 4 and 5 contain the description of epiphytic cryptogam communities (bryophytes and macrolichens) in primary and secondary forests. Trees were climbed using a mountaineering-derived single rope technique and were sampled from the base up to the twigs of the outer canopy. The relevés taken in each height zone represented the complete variation of the epiphytic vegetation. Percentage cover of corticolous bryophyte and macrolichen species was estimated and later compared using Detrended Correspondence Analysis (DCA) and non-metric Multi-response Permutation Procedure (MRPP). Bark samples from the investigated trees were extracted with deionized H2O and analysed for pH.Chapter 4 pays attention to the epiphytic cryptogam communities on the two dominant host tree species (Quercus copeyensis and Q. costaricensis) of upper montane oak forests in Costa Rica. For the first time, a detailed description of epiphytic cryptogam communities of whole standing canopy trees in an upper montane oak forest is given.Chapter 5 compares species richness, community composition and ecology of cryptogamic epiphytes in primary and recovering upper montane Quercus forests of Costa Rica. Canopy trees of Quercus copeyensis were sampled with the aim of getting insights into recovery potential, underlying patterns and processes of epiphyte succession following anthropogenic disturbance.