POSTFIRE REGENERATION OF A MEDITERRANEAN HEATHLAND IN SOUTHERN SPAIN

Fire is a recurrent disturbance in the vegetation of Mediterranean cli mate regions. Most of the woody species (16 out of 19) in a Mediterran ean heathland community, in the Strait of Gibraltar region of southern Spain, sprouted from subterranean vegetative organs after a wild-fire . Dominant sprouters were the prostrated oak Quercus lusitanica, three gorses, Genista tridens, G. tridentata and Stauracanthus boivinii, an d a heath, Erica scoparia. About 100 seedlings m(-2) of 14 woody speci es were censused in the first three years after fire. The highest dens ity of seedlings was recorded for heather (Calluna vulgaris), a rockro se (Cistus populifolius subsp. major) and a gorse (Genista triacanthos ). Woody vegetation covered up to 85% of the soil surface in the third year after fire. At this stager the community was co-dominated by the sprouters Quercus lusitanica (21%), Genista rridentara (21%) and Stau racanthus boivinii (20%), and the seeder Cistus populifolius subsp. ma jor (20%). A total of 52 herbaceous species, many of them (35) perenni als, was recorded, showing a temporal change in species composition. T he role of fire influencing community diversity and the consequences f or the conservation of heathlands in the Strait of Gibraltar region, a re discussed.