The influence of fire severity, serotiny, and post-fire management on Pinus pinaster Ait. recruitment in three burnt areas in Galicia (NW Spain)

Abstract

The effect of fire severity and post-fire management on Pinus pinaster recruitment was evaluated in three burnt areas in Galicia (NW Spain) exhibiting different levels of serotiny. Three sites were sampled, each of which had two of the following levels of fire severity: combusted crown, scorched crown and unaffected crown. Viable seed rain was closed related to the canopy cone bank and stand serotiny level. Soil burn severity also favoured seed dispersal. Relative germination success increased with soil burn severity whereas initial and final seedling density depended on both the canopy cone bank and soil burn severity. A positive influence of fire severity on the final/initial seedling density and final density/total seed dispersal ratios was also observed. Different post-fire management options were used at each experimental site following local operational routines. Harvesting and slash logging resulted in significantly higher seedling mortality. However, at the end of the study period, seedling density in all stands was sufficient to ensure re-establishment of P. pinaster forest.