Abstract. Fire is an integral part of many ecosystems, including the Mediterranean ones. However, in recent decades the general trend in number of fIres and surface burnt in European Mediterranean areas has increased spectacularly. This increase is due to: (a) land-use changes (rural depopulation is increasing land abandonment and consequently, fuel accumulation); and (b) climatic warming (which is reducing fuel humidity and increasing fIre risk and fIre spread). The main effects of fIre on soils are: loss of nutrients during burning and increased risk of erosion after burning. The latter is in fact related to the regeneration traits of the previous vegetation and to the environmental conditions. The principal regeneration traits of plants are: capacity to res prout after fIre and fIre stimulation of the establishment of new individuals. These two traits give a possible combination of four functional types from the point of view of regeneration after fIre, and different relative proportions of these plant types may determine the post-fIre regeneration and erosion risk. Field observations in Spain show better regeneration in limestone bedrock type than in marls, and in north-facing slopes than in southfacing ones. Models of vegetation dynamics can be built from the knowledge of plant traits and may help us in predicting post-fIre vegetation and long-term vegetation changes under recurrent fIres.

Question: What are the main forces driving natural regeneration in burned mature Mediterranean forests in the medium‐long term and what are the likely successional trajectories of unmanaged vegetation? Location: Valencia Region, eastern Spain. Methods: A wildfire burned 33 000 ha of Pinus halepensis and P. pinaster forest in 1979, and subsequent smaller wildfires took place between 1984 and 1996. The study was designed to sample the range of environmental and disturbance (fire recurrence and land use) conditions. The territory was classified into 17 different geomorphological and fire‐recurrence units. Vegetation cover and floristic composition were measured on a total of 113 plots (1000 m2 each) randomly selected within these units. Results: The results show that 23 years after the fire the regenerated vegetation consists of successional shrublands, and that forest ecosystem resilience can be very low. The vegetation presents a strong correlation with most of the environmental variables, but fire (one or two fires), soil type and land use (in that order) are the main drivers of vegetation composition. Quercus coccifera shrublands persist on limestone soils while diverse types of other shrublands (dominated by seeder species) are found on marl soils. Conclusions: The results of this study indicate that disturbance factors strongly coupled to human activities, such as land use and fire, play a critical role in the current state of vegetation. Fire creates vegetation patches in different successional states while land use and soil type define the different types of shrubland in terms of their specific composition.

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-Pine litter fall data, mainly needle litter, were available for 64 plots in a transect from the Arctic Circle in Fennoscandia (41 plots) to southern Spain (22 further plots in continental Europe) and one in the American Midwest). Data originated from a total of eight pine species. Regressions were calculated mainly for needle litter fall and to some extent for total litter fall. We obtained a highly significant linear relationship for needle litter fall and latitude (R 2 adj = 0.285; n = 58; P < 0.001) when using needle litter fall data from all pine species. Combining sites in the boreal and Atlantic climates gave an R 2 adj of 0.732 with n = 45 (P < 0.001). A multiple linear relationship using stand age, latitude and basal area was highly significant and gave an R 2 adj value of 0.412 (n = 54; P < 0.001). For the amount of Scots pine needle litter in Fennoscandia, the best simple linear relationships were obtained with site index (H 100) (R 2 adj = 0.349), latitude (R 2 adj = 0.331) and basal area (R 2 adj = 0.324) as predictor variables, whereas the regressions on altitude and stand age were significant only with P < 0.01. An X 2 function for stand age improved the relationship with age to R 2 adj = 0.243. Multiple regression relationships for Fennoscandia between needle litter fall and latitude plus basal area and that to latitude plus basal area plus age were highly significant (R 2 adj = 0.605 and 0.661, respectively, with n = 41).

Question: What is the effect of fuel management practices in the recovery capacity of seeder‐dominated shrublands? Location: Ulex parviflorus shrubland localities in Mediterranean regions of eastern Spain. Methods: We applied prescribed burning and brush‐chipping as fuel management techniques in three young and three mature shrublands, and evaluated the effects in the following four years. Results: Canopy opening by the treatments allowed increasing species richness through the four years of secondary succession. The treatments produced a change in community structure and dominant species, from the woody seeder Ulex parviflorus to the resprouter grass Brachypodium retusum. Vegetation response was conditioned by both shrubland developmental stage and treatment applied. Burning resulted in more severe modification of the ecosystem, increasing bare soil cover. Four years after fuel management in different aged Mediterranean gorse shrublands, vegetation response followed a similar pattern with the exception of the young, brush‐chipped shrublands. The treatments applied for controlling Ulex parviflorus were seen to be very effective, with the exception of brush‐chipping in young shrublands. Conclusions: Selective brush‐chipping in middle‐aged or mature gorse shrublands would combine a drastic reduction in fire hazard with ecosystem conservation and regeneration.