Post-fire regeneration variability of Pinus halepensis in the eastern Iberian Peninsula

Post-fire regeneration of Pinus halepensis, the most abundant tree in the Mediterranean Basin, can vary largely. In the present work, we aim to study the parameters determining this variability in the eastern Iberian Peninsula. For this reason we sampled in 2002 the sapling pine density on 22 plots that burned in 1993 and 71 plots that burned in 1994. Pre-fire vegetation (tree density and basal area) were obtained from the Spanish Forest Inventory. The regeneration ranged from 0.006 to 20.4 pines/m(2) (mean = 1.24, S.D. = 3.22). The statistical analysis suggested that the most important variables explaining this variability were the amount of branches found on the forest floor (branches collapsed from burned trees or branches left by foresters), the aspect of the plot, the pre-fire basal area, and whether the slope was terraced or not. High regeneration was observed in forests with large amounts of branches on the floor (which create appropriate microclimatic conditions), with northern aspects, with high pre-fire basal area, and on terraced slopes. Furthermore, other water-related variables (annual precipitation and slope) also had some (although lower) importance. These results have direct implications for forest managers in the study area. (C) 2004 Elsevier B.V. All rights reserved.