Structural analysis of woody species in Mediterranean old fields.

The first part of this study provides an overview on Sicilian olive systems. Subsequently, the study describes the differenttypologies of cultivated agroforestry systems present in South-Eastern Sicily employing olive trees in association with otherMediterranean tree species, in particular for the production of firewood, coal and animal food (downy or pubescent oak,holm oak, cork oak), but also in association with forage or grazing species (oat, barley, vetch, etc.) or cereals. The studyshows that Sicilian agroforestry systems are much more diversified than it was known so far. In the second part, the studydescribes the spontaneous colonization processes by plants, observed in abandoned olive agroforestry systems and leading tothe formation of more complex ecosystems (renaturation). Most of the previously described agroforestry systems are atpresent subject to abandonment. Our analysis of secondary succession dynamics shows how woody species, and above allthose species which are part of the cultivated system, rapidly colonize abandoned areas, so that a maquis-wood is formedwithin few decades.