XVI International Botanical Congess

Cloud forests (Bosque Mesófilo de Montaña) are among the most threatened in Mexico. Hence, it is crucial for their conservation to understand their successional dynamics. Epiphytes, which constitute 30% of their flora, have scarcely been studied. Our project aims at recognising the abundance and diversity of cloud forests in Oaxaca (Mexico's most important). We are comparing both Epiphytes cover and composition in a time sequence ranging from secondary (15 years) to mature (³100 years) cloud forests. Preliminary results show that: 1) both variables are associated with the succesional stage, 2) cover at the trunk's base (0 - 1.6 m) grew from 11.39% in the former forests to 73.95% in the latter, 3) diversity increases with the successional stage, and 4) Liverworts are the most abundant Epiphytes.