INFLUENCE OF FIRE ON PLANT-REGENERATION IN A STIPA-TENACISSIMA L. COMMUNITY IN THE SIERRA-LARGA MOUNTAIN-RANGE (SE SPAIN)

The range of communities dominated by Stipa tenacissima extends from U kraine to North Africa. They contain several endemic species in Spain. The post-fire response of a community of S. tenacissima in semiarid S E Spain was studied by following the dynamics of the floristic richnes s and plant cover during the first four years. The importance of S. te nacissima was noticed during recolonization of these zones, where, thr ee years after a fire, the high degree of cover was similar to that of unburned areas. The prolonged drought during the study period uas the probable cause of difficulties in recolonization of the burned area b y the three obligate seeder species (Pinus halepensis, Rosmarinus offi cinalis, and Cistus clusii) which were widespread in the unburned comm unity. Juniperus phoenicea did not sprout after the fire, and four yea rs later no seedlings were encountered in the burned area. According t o the results, the endemic plants living in the S. tenacissima communi ty were not negatively affected by fire; the twelve endemic species fo und in this community were all capable of responding to the fire eithe r through new shoots or by reproduction through seeds.