Post-fire succession in two Quercus pyrenaica communities with different disturbance histories

Quercus pyrenaica is a widely distributed oak species in the Iberian Penins ula which has been subjected to drastic disturbances, such as fire, leading to a significant decrease in its cover. The main objective of this study w as to carry out a comparative analysis of the post-fire regeneration of two Quercus pyrenaica ecosystems. Prior to being burned by a wildfire at the e nd of the summer in 1985, the first ecosystem presented a developed toe lay er, whereas the second one was in a shrub layer stage. In each ecosystem a permanent plot was established and sampled for a period of 6 years after th e disturbance. Colonisation rate!; of different biological types were estim ated, as well as the structural parameters defining the community: species diversity, richness and evenness. These results allowed us to determine a p ost-fire successional model for these ecosystems. Post-fire species composi tion of the two sites was similar, but abundance of particular species vari ed as a function of pre-fire abundance. ((C) Inra/Elsevier, Paris.).