Resumo

LOPEZ-LOPEZ, Miguel Ángel; VELAZQUEZ-MARTINEZ, Alejandro; ACOSTA-MONTOYA, Juan  e  ESTANOL-BOTELLO, Elizabeth. Biomass distribution in declining sacred-fir seedlings. INCI [online]. 2006, vol.31, n.6, pp.451-455. ISSN 0378-1844.

In the forests located west and southwest of Mexico City, decline of sacred-fir Abies religiosa (H.B.K.) Schl. et Cham. has been observed for the past 25 years. Characterization of the phenomenon from different viewpoints is important if knowledge of the problem is to be increased and viable solutions pursued. For this reason, changes in biomass allocation patterns, as a consequence of decline in 7-year-old seedlings were investigated. A completely randomized experiment with three degrees of damage as treatments: slight, intermediate and severe; and eight replicates per treatment was established. The biomass of the seedling components was significantly reduced as the damage increased. Root was the most affected organ followed by twigs. However, twigs accumulated biomass through time producing an imbalance between aboveground and root biomass. Even though this imbalance is offset by leaf fall, this brings about a further reduction in the amount of carbon fixed.

Palavras-chave : Abies religiosa; Biomass Distribution; Forest Decline; Seedling.