Print version ISSN 1405-3195
LARA-GONZALEZ, Rogelio; SANCHEZ-VELASQUEZ, Lázaro R. and CORRAL-AGUIRRE, Juan. Regeneration of Abies religiosa in canopy gaps versus understory, Cofre de Perote National Park, México. Agrociencia [online]. 2009, vol.43, n.7, pp. 739-747. ISSN 1405-3195.
Some studies have shown that fir (Abies spp.) regeneration can occur either in canopy gaps or in understory. The purpose of this study was to know how canopy gaps contribute to fir regeneration. Points were randomly chosen in three fir forests, and starting from there the nearest gap was recorded. Likewise, other random samples were placed in understory with the same diameter as that of the gap registered before. Gap age, gap size, and tree seedling for each sample were recorded. The average gap age was 7.61 ±1.86 yr. The average gap size was 66±42.8 m2. The most common gaps were of intermediate size (44-88 m2). Only seedlings of A. religiosa (H.B.K.) Schlecht. & Cham and Pinus montezumae Lamb, were observed either in gaps or in understory. The number of seedlings was higher in gaps than in understory (p<0.001). The average number of seedlings in gaps was 4 430 ±596 per ha (A. religiosa 95.7 % and R montezumae 4.3 %), whereas in understory it was 993±316 pef ha (A. religiosa 99 % and P. montezumae 1 %). There was a significant relationship between gap age and number of seedlings of A. religiosa (R=0.62, p<0.001). The gap size and the interaction gap size-age were not significant (p>0.23) and did not explain the regeneration density.
Keywords : Abies religiosa; canopy gap; disturbances; fir forest; México; regeneration.