Comparative study of the aerial structure of five shrubs of mediterranean shrublands

Abstract

Each year hundreds of thousands of hectares of forests and shrublands are destroyed by wildfires in countries of the western part of the Mediterranean Basin (France, Italy, Spain). Structural canopy components influencing flammability and fire behavior were studied for five Mediterranean shrub species. For each species, total fuel loading, available fuel loading, and vertical distribution of different fuel particles [leaves, twigs of different diameter classes (alive or dead) and stratas] were estimated in a 30-yr-old shrubland. Live to dead fuel ratio, size distribution, and porosity were calculated and compared. The results revealed three groups of species with regard to the fire hazard they present. They are, from the lowest to the highest hazard: (1) Cistus salvifolius, Pistacia lentiscus, and Rosmarinus officinalis with low fuel loadings, (2) Phillyrea angustifolia with high fuel loadings and the highest porosity, and (3) Genista scorpius having the highest fine fuel loading and dead material values. © 1991 by the Society of American Foresters.