Ecological approach in selecting extensive green roof plants: A data set of Mediterranean plants

The need of planning more sustainable cities leads to a wider use of extensive green roofs (EGRs) as they provide significant advantages to the urban environment (e.g., energy conservation and increase of biodiversity). In Central and North Europe, as well as in North America and Asia, EGRs are generally included in new building designs, whereas they are still uncommon in Mediterranean countries. The adaptations of many Mediterranean plants to drought stress and their floristic diversity constitute, however, positive elements in finding solutions for them. This research proposes a methodological approach to select wild species for EGRs based on ecological characteristics (using natural ecosystems as templates for green roof design). An extensive bibliographic search on plants proposed for EGRs in Mediterranean countries has led to the creation of a wide database. Other plants were selected considering their synecological, structural, and autoecological characteristics. All the data were integrated in a comprehensive database of 138 taxa potentially suitable for setting EGRs according to their syntaxonomical classification and their ecological behavior (fitting both the Mediterranean and EGR environmental conditions). The selected taxa could enlarge the pool of species for EGRs in Mediterranean cities, increasing urban biodiversity.