Fogo e dinâmica da comunidade lenhosa em cerrado sentido restrito, Barra do Garças, Mato Grosso

Abstract

Studies on the dynamics and structure of woody vegetation after natural fires in Parque Estadual da Serra Azul have shown that fire affects plant survival and growth. The response of vegetation to fire depends on intensity, frequency and duration of burning. Ten plots (20 × 50 m) (Area 1) were burned in 2002 and 2005. Another ten plots (Area 2) were burned in 2002, 2005 and 2007. In January 2009, in Area 1, tree mortality was lower (2.0%) and recruitment (3.7%) higher than that observed Area 2 (4.3% and 0.05% respectively). Plant mortality decreased with increasing size class. In Area 2, there was a reduction in plant size (height and diameter). The resprouting pattern after fire was related to plant size. Smaller size classes had higher proportions of resprouting at the base of the stem while the larger size classes had more resprouts at the tree crown. In Area 2, species richness was reduced (estimated by Jacknife and Chao 2). Our results suggest that the tolerance of adult trees and smaller plants due to resprouting may explain the persistence of the woody cerrado community submitted to a fire regime interval over five years.