Linking forest diversity and tree health: preliminary insights from a large-scale survey in Italy

Forest health is currently assessed in Europe (ICP Forests monitoring program). Crown defoliation and dieback, tree mortality, and pathogenic damage are the main aspects considered in tree health assessment. The worsening of environmental conditions (i.e., increase of temperature and drought events) may cause large-spatial scale tree mortality and forest decline. However, the role of stand features, including tree species assemblage and diversity as factors that modify environmental impacts, is poorly considered. The present contribution reanalyses the historical dataset of crown conditions in Italian forests from 1997 to 2014 to identify ecological and structural factors that influence tree crown defoliation, highlighting in a special manner the role of tree diversity. The effects of tree diversity were explored using the entire data set through multivariate cluster analyses and on individual trees, analysing the influence of the neighbouring tree diversity and identity at the local (neighbour) level. Preliminary results suggest that each tree species shows a specific behaviour in relation to crown defoliation, and the distribution of crown defoliation across Italian forests reflects the distribution of the main forest types and their ecological equilibrium with the environment. The potentiality and the problems connected to the possible extension of this analysis at a more general level (European and North American) were discussed

Le aree forestali italiane di FunDivEUROPE: un nuovo progetto FP7 sul significato funzionale della biodiversità forestale in Europa

Abstract: The Italian forest sites of FunDivEUROPE: a new FP7 project on the functional significance of forest biodiversity in Europe. FunDivEUROPE is a new project aiming at a deeper understanding of the role of forest diversity on ecosystem functions and service provisioning for society. This project combines three scientific platforms: experimental, exploratory and inventory. The exploratory platform is based on the observation of a broad range of properties, traits and ecological processes on a network of ca. 240 natural forest sites representing a gradient of tree species diversity in six focal regions of Europe (Spain, Italy, Germany, Poland, Finland and Romania). The Italian sites are located on the hills of central and Southern Tuscany and represent the category "thermophilous deciduous forest". Almost one year of fieldwork was needed to select and characterize 36 plots measuring 30 x 30 m. Selection was based on criteria concerning tree mixtures and richness, structural parameters and main environmental variables. The main features of these sites are synthetically presented in this paper together with a short description of the project structure and scope. The aim is also to enhance dissemination of the potential implications for a sustainable forest management in Italy