THE VULNERABILITY OF QUERCUS SUBER L. TO FIRE IN THE SERAÏDI FOREST (EDOUGH) IN NORTH-EAST ALGERIA: THE FIRE SEVERITY, THE RESPONSES OF CORK OAK AND XYLOPHAGOUS INSECTS AFFECTING BURNT TREES

Abstract

Two plots were set up to study the regeneration capacity of cork oak and the modalities for vegetative response after wildfire. These plots were installed approximately six months after the fire; for the virgin El Fahama site (which was burnt down on 4 August 2015) and for the Ain Attaoua site (which was burnt down on 31 July 2016 and exploited in the summer of 2011). In total, 121 trees were selected and divided between 55 trees in the El Fahama plot (monitored 6, 18 and 30 months after the fire) and 66 trees in Ain Attaoua (monitored 6 and 18 months after the fire). We also took into account the presence/absence of attack holes by the xylophagous insects Platypus cylindrus and Cerambyx cerdo in the burnt trees. The fire at the two study sites, was considered to be violent, for the trees studied. Over 76 % of the trees were burnt to the ground. At the end of the study, most of the burnt trees had resumed their physiological activity, with a mortality rate varying between 7.25 and 22.72 %. Sprouting from the crown and base simultaneously was also, recorded on 7.27 to 8 % of the sample trees. The results of the infestation of the trees show that 10 % of the trees studied were attacked by P. cylindrus and that the insect settled on the trees following a strategy linked to the following dendrometric characteristics: (height 6 to 8 m, circumference > 110 cm) and exploitation status (unexploited trees).

Keywords

• wildfire
• cork oak
• vegetative response
• mortality
• xylophagous insects