Holm oak (Quercus ilex L.) forests and woodlands have been considered as a paradigm for Mediterranean terrestrial ecosystems. In the western part of the Mediterranean Basin, these forests and woodlands occupy large areas and thus play a very important role in the landscape. A number of research projects from the Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), the Centre de Recerca Ecológica i Aplicacions Forestals (CREAF), and from many other laboratories are currently focusing on Q. ilex ecosystems, and a number of problems have appeared concerning not only basic knowledge but also management aspects. For this reason, the CEFE and the CREAF decided to jointly organize the workshop on Quercus ilex L. Ecosystems, which was held in Montpellier and Barcelona in September 1990. The present volume consists of a selection of papers presented during the workshop and other papers contributed after the workshop. The papers are divided into five sections: Biogeography and History; Structure, Productivity and Dynamics; Water Relationships; Nutrient Cycling; and Management.

Used by humans since ancient times, evergreen oak forests still cover extensive mountain areas of the Mediterranean Basin. These broadleaved evergreen forests occupy a transitional zone between the cool-temperate deciduous forest biome and the drier Mediterranean pine forests and shrublands. Slow growing and casting a deep shade, the sclerophyllous holm oak (Quercus ilex) absolutely dominates the closed canopy of many Mediterranean evergreen oak forests. This is a synthesis of 20 years of research on the structure, function, and dynamics of holm oak forests in two intensively studied experimental areas in Spain. By combining observational measurements at the leaf, tree, plot, and catchment scales with field experiments and modelling, the authors explore how these forests cope with strong water limitation and repeated disturbances.

With more than 500 species distributed all around the Northern Hemisphere, the genus Quercus L. is a dominant element of a wide variety of habitats including temperate, tropical, subtropical and mediterranean forests and woodlands. As the fossil record reflects, oaks were usual from the Oligocene onwards, showing the high ability of the genus to colonize new and different habitats. Such diversity and ecological amplitude makes genus Quercus an excellent framework for comparative ecophysiological studies, allowing the analysis of many mechanisms that are found in different oaks at different level (leaf or stem). The combination of several morphological and physiological attributes defines the existence of different functional types within the genus, which are characteristic of specific phytoclimates. From a landscape perspective, oak forests and woodlands are threatened by many factors that can compromise their future: a limited regeneration, massive decline processes, mostly triggered by adverse climatic events or the competence with other broad-leaved trees and conifer species. The knowledge of all these facts can allow for a better management of the oak forests in the future.