A comparative study of aboveground biomass of three Mediterranean species in a post-fire succession

The aboveground biomass of three woody species (Cistus albidus, Quercus coccifera and Pinus halepensis) in two early successional stages (3- and 10-year old) of a post-fire Mediterranean ecosystem was investigated. Among these three species, which belong to the successional series of holm oak (Quercus ilex), C albidus and Q. coccifera are two dominant shrub species in the garrigue ecosystem and P halepensis is a pioneer tree species widely represented in the Mediterranean area. The results obtained showed that in monospecific stands, C albidus and Q. coccifera had a high recovery potential. In the 3-year-old stands, the cover of P. halepensis was only 19.8% for a total biomass of 0.75 +/- 0.21 t ha(-1), while the plant cover of C. albidus and Q. coccifera was, respectively, 26% and 85.5% and biomass was 4.72 +/- 1.09 and 11.5 +/- 0.16 t ha(-1). Only 10 years after fire, the plant cover of C albidus and Q. coccifera was, respectively, 55% and 100% and total biomass 13.2 +/- 1.7 and 35.8 +/- 4.7 t ha(-1). The greatest increase in biomass was noted for P halepensis (29.7 t ha(-1)). If mean annual biomass increments are considered, it appears that there was a significant decrease with the stand age for the two shrub species although the tree species showed an increase in productivity. These differing patterns in biomass and productivity of shrub and tree species with stand age provide information on biomass accumulation rates of pioneer species in a Mediterranean succession and their importance in the vegetation dynamics. (C) 2003 Elsevier SAS. All rights reserved.