Early post-fire regeneration dynamics of Brachypodium retusum Pers. (Beauv.) in old fields of the Valencia region (eastern Spain)

Extensive wildfires have affected the Valencia region in the last two decades. A large portion of the burnt areas has been localised in old fields. Although Mediterranean communities are usually resilient to fire and recover very quickly to the pre-fire state, burnt old fields with a low number of species could show poor recovery capacity. The response capacity of these systems to fire, and, especially, the role of the native herbaceous Brachypodium retusum were studied. Two years after fire, plant cover reached a value of 56 %. Resprouter species were more important in number and in specific cover. B. retusum represented the species with the highest contribution to total plant cover for all the study period. Total biomass in burnt plots was always lower than in unburnt plots. However, B. retusum green biomass showed a quick recovery to pre-disturbance levels, and below-ground biomass was similar in burnt and unburnt plots. Reproductive biomass greatly increased in burnt with respect to unburnt plots during the first post-fire year, with no stalk production in unburnt plots. B. retusum may be considered a promising species for the restoration of extremely degraded lands because of its high resilience to fire.