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Fire is an ecological factor that has been present in the ecosystems of the Mediterranean region for thousands of years. Our study was undertaken to acquire knowledge of the effect of fire on the germination of Mediterranean species. We used high temperatures (up to 60°C) and smoke to determine the effect of these factors on the germination of species from the Mediterranean region. The species selected are characteristic of the central Mediterranean basin and are representative of both woody and herbaceous species: Rhamnus alaternus L., Cistus albidus L., Cistus monspeliensis L., Fumana ericoides (Cav.) Gand., Rosmarinus officinalis L., Melica ciliata L., Avena sterilis L., Bituminaria bituminosa (L.) C.H. Stirt., Anthyllis vulneraria L., Coronilla glauca L., Argyrolobium zanonii (Turra) P.W. Balland, Emerus major Mill., Genista scorpius (L.) D.C. and Spartium junceum L. The seeds were collected in Mediterranean shrubland (8) and woodland (6) ecosystems, around Montpellier, France (24°45 0 N and 3°50 0 E). Ten treatments were tested: a control, three smoke treatments and six heat treatments. The average germination level (germination percentage) and the average T 50 rates (time taken to reach 50% of germination) were calculated. The smoke and heat act in a different way on each of the species. The smoke enhanced the germination of two species, whilst moderate heat increased germination in all of the species excepting R. officinalis, F. ericoides, A. sterilis, A. vulneraria, and G. scorpius. Germination was fastest in M. ciliata and S. junceum and slowest in A. sterilis, E. major and C. albidus. The cues did not significantly affect the rate of germination. Fire modified the germination response of 12 of the 14 species studied.

The purpose of this study was to determine whether fire recurrence modifies the regeneration capacity of Quercus coccifera garrigues in the Valencia region ͑eastern Spain͒. We studied several areas with different fire recurrences ͑1, 2 and 3 fires in 16 years͒, all of which had sustained a common last fire in 1994. Three-and-a-half years after the last fire, differences between the 3 fire recurrences were not detected with respect to total plant cover and Q. coccifera cover, with a mean value between 92 and 76%. On the most frequently burned sites, herbaceous and subshrub species cover showed a tendency to increase, while that of the obligate seeding shrub, Ulex parviflorus, decreased with both fire frequency and shorter last-fire interval. The most recurrently burned areas with the shortest last-fire intervals presented higher species richness, which mainly affected the herbaceous and subshrub species group, and of these, the hemichryptophytes. The major effect of fire recurrence was the significant decrease in stem and total biomass of Q. coccifera in the three studied sites. Three-and-a-half years after the fire, the mean total biomass values were around 1500, 1000 and 700 g. m -2 in the garrigues with 1, 2 and 3 fires respectively. Stem production was more affected than leaf production. Leaf area index values showed the same pattern as leaf biomass. Recurrent fires also caused a decrease in net primary production measured the fourth year after fire. The results point to the fact that fire recurrence can cause depletion in garrigue productivity and recovery capacity in southern areas, in contrast with the high resilience observed in northern Mediterranean garrigues.