Ecología ligada al fuegoresiliencia en rebollares y brezales

Abstract

Fire is an important environmental factor that has shaped Cantabrian Mountain landscapes. The aim of this work is to do a revision of the main processes and traits in the post fire recovery in two ecosystems types, Quercus pyrenaica forests and heathlands, very spread over the Cantabrian Mountain chain. Community plant diversity increases in the first years after fire, mainly due to the fast recovery of herbaceous species and the reduced competition with shrub species. Recovery takes place both by fire stimulation of seed germination and by resprouting from underground organs, which survived due to the bad diffusion of heat in the soil. Herbaceous species tend to reduce their cover in the following years, when the woody species, characteristics of these communities, recuperate their dominance. In these ecosystems, woody species are mainly post fire resprouters. This is the case of trees as Q. pyrenaica, and also shrubs as Erica australis, Gcnistelln tridentata, Cytisus scoparius or Genista Ikuida. Moreover, the survival of roots and other underground regenerative organs is very important in prevent soil erosion. Although vegetative resprout is the dominant mechanism of recovery after the fire, there are also many species with seed whose germination is stimulated by the soil heating. Some of these post-fire seeders, frequent in these ecosystems, are Halimium umbellatum, Halimium alyssoides and Calluna vulgaris. In general, in all the studied sites, structural features are similar to pre-fire conditions in a few years. Si these communities can be classified as systems with a high resilience to wildfires.