Abstract: |
The presence of Pinus halepensis Miller and Pinus pinea L. in Sardinia can be dated to very ancient times, furthermore they have been largely used since the '20s for reforestation, mainly along the cost. In the paper we analyze different aspects of the recent naturalization and invasion processes after fires. The main biological and ecological properties of these two pine species are seemingly a good explanation for invasive ability in some habitats in the insular environment, even though the general conditions could be better and allow wider diffusion. Climatic factors, geo-pedology, fires, low vegetation cover, human made habitats and disturb, land abandon, are the main driving forces in the occupation of new space, analogous with what happens in other areas in the Mediterranean region or in Mediterranean-like regions in the world.Aleppo pine is an heliophilous and thermophilous species that prefers calcareous soils. It requires little, and it is well suited to the variable Mediterranean climate. The seedlings are very demanding in terms of light requirements. It has adaptive traits that favor the colonizing of burned areas and also of other suitable habitats. This aspect has been highlighted by many authors The capacity of renewal in burned areas is due to a complex set of adaptive traits, but the expansion process seem to be quite a new phenomenon in the island of Sardinia, taking place at a considerable rate. We have localized and mapped the sites in the Island where this process is most evident, recording the population traits of Aleppo pine renewal and vegetation of the sites, mainly focusing on recent huge forest fires since the last twenty years. |
