Resumo

NERI-PEREZ, AC; RODRIGUEZ-TREJO, DA  e  CONTRERAS-AGUADO, R. Flammability of forest fuels in the tropical forest of Calakmul, Campeche. Universidad y ciencia [online]. 2009, vol.25, n.2, pp.121-132. ISSN 0186-2979.

This study was carried out in the Calakmul Biosphere Reserve, Campeche, in order to determine the flammability of five types of tropical forests, one of them in two conditions: subperennifolious tropical high forest (tropical rain forest), subperennifolious tropical high forest affected by fires, subperennifolious tropical medium forest (subperennifolious tropical moist forest), subcaducifolious tropical medium forest (subcaducifolious tropical moist forest), subcaducifolious tropical low forest (tropical dry forest) and tropical low flooded forest (flooded tropical dry forest). Also compared was the flammability among three layers of forest fuels: herbaceous, leaf litter and fermentation layer. Four flammability components were studied. The time to ignition (ignitibility)was evaluated recording the time to independent ignition. The duration of combusion (sustainability) was determined from the time of ignition to the end of combustion. The liberated heat (combustibility) was estimated as the combustion heat, and recorded with a calorimeter. The proportion of the burnt fuel (consumibility) was evaluated as the percentage of burnt fuel. Each parameter of flammability was compared among vegetation types and fuel layers with a completely randomised experimental design and an analysis of variance. The medium subcaducifolious tropical forest presented a faster ignitibility and a lower combustibility, consumibility and sustainability, in comparison with the subperennifolious tropical high forest. Comparing layers, the ignitibility was slower in the fuels in the fermentation layer than in the herbaceous and leaf-litter layers. The combustibility, consumibility and sustainability were greater in the fermentation layer than in the leaf-litter layer, as well as in this last layer compared with the herbaceous layer.

Palavras-chave : Ignitibility; combustibility; sustainability; consumibility.