Epiphytic bryophytes are sensitive to disturbance and environmental change. Epiphytic bryophytes growing on Lithocarpus xylocarpus (Kurz) Markgr. trunks of different diameter classes were surveyed and analyzed to determine species composition and richness in primary and secondary Lithocarpus forests in Ailao Mountains, SW China. Among the 65 species belonging to 32 genera, 19 families found, 28 occurred in both forests. Species richness and total coverage in primary forest were significantly higher than in secondary forest. It is suggested that a period of perhaps much more than 110 years is necessary for the recovery of epiphytic bryophyte flora in the montane forest of SW China. Fan, turf, and smooth mat are the most important life forms, with high occurrences in both forests. The life form composition of epiphytic bryophytes is determined mainly by microhabitat and host age. Tree age explained most variations in epiphytic bryophyte flora. Primary forest is a favorable habitat for epiphytes, due mainly to its diversified canopy structure and the presence of large diameter hosts. Moisture-laden southwest trade winds and forest structure could differentiate microclimate and impel a distinct composition of epiphytes in windward and leeward exposures.

Keywords: Epiphytic bryophyte; Richness; Life form; Recovery; Humidity