Lluvia de semillas y emergencia de plántulas de Fagus grandifolia subsp. mexicana en La Mojonera, Hidalgo, México

Abstract

Fagus grandifolia subsp. mexicana is a species restricted to small populations under high anthropogenic pressure. With the aim to attain information to propose conservation strategies of this species, the seed rain and demography of current-year seedlings were analyzed at La Mojonera, Hidalgo, Mexico. A 4 800 m2 plot divided into 10 X 10 m quadrants was established. The seed rain, seedling emergence, and survival were analyzed using seed traps of 0.5 m2 and adjacent 1 m2 sub-plots. The total seed rain was 521 667 seeds ha-1. A high proportion of seeds were unsound (46.01%), followed by damaged seeds (29.5%) and only 24.44% were sound. Emerged seedlings fluctuated from 1 to 33 seedlings m2. After 10 months, 2.8% of emerged seedlings were alive. Seedlings that emerged first showed higher survival probability. Important mortality causes were herbivory (34.44%), damping-off (24.07%) and unknown causes (23.65%). This species presents the general pattern of tree species in seedlings survival, showing a high mortality rate during the first year.