Fire behavior in native species of the Caatinga in the immediate geographical region of Patos-PB

ABSTRACT

The use of fire in a controlled way in vegetation can provide positive results, however, it can spread in an uncontrolled way in the area, causing damage in the most diverse aspects. The objective of this research was to evaluate the burning characteristics of species found in the immediate geographical region of Patos when submitted to the action of fire. 10 treatments were evaluated with 3 repetitions, consisting of combustible material from the Caatinga. These materials were collected in 60 kg nylon bags and air-dried for subsequent burning. Flame height and temperature, ignition time and frequency, propagation speed, burning duration, fire intensity and the ash content were evaluated. In the speed of propagation of the flames, we identified statistical superiority of Aristida adscensionis with 0.0335 m s-1, and also in the intensity of the fire, in which 402.43 kcal m-1s-1 were responsible for the classification in very high severity. The maximum burning duration was found in the Anadenanthera colubrina plots, with an average of 24 min. The Mimosa tenuiflora obtained the lowest wood ash content, which is favorable for its energy potential. Cnidoscolus quercifolius is a species of low flammability, in view of the difficulty in igniting and maintaining combustion. Places with the abundant presence of Aristida adscensionis should be monitored frequently for the risk of occurrence of fires, especially in times conditions such as high air temperature and low humidity favorable to the occurrence of fire.

Keywords
Vegetation flammability; Forest fuel material; Dry forests