Influence of tree species richness on tree growth and intrinsic water-use efficiency after drought in tree plantations in north-eastern Italy

• Published in: European journal of forest research 2020-10, Vol.139 (5), p.869-877
• Main Authors: Palandrani, Chiara, Battipaglia, Giovanna, Alberti, Giorgio
• Format: Article
• Language: English
• Subjects: Biomedical and Life Sciences; Forestry; Life Sciences; Original Paper; Plant Ecology; Plant Sciences
• ISSN: 1612-4669; 1612-4677
• DOI: 10.1007/s10342-020-01291-7

Recent studies have highlighted that higher species richness can increase the resistance and/or the resilience to disturbances and stresses. The present study quantifies the overall tree species richness effect on growth and intrinsic water-use efficiency (iWUE) in three target tree species (i.e. Fraxinus excelsior , Juglans spp. and Prunus avium ) after drought in six deciduous plantations in the Friuli-Venezia Giulia plain, North-eastern Italy. Planting densities, management, climatic and soil characteristics were the same at all the plantations. Stands differed only for their total surface area and for their total tree species richness (3, 4, 6, 7, 8 and 9). We double-sampled 15 dominant trees for each of the three target species, we measured tree-ring width, and we removed age-related trends using a detrending function. We selected 2006 as the driest year at the sites and 2014 as the reference year using the De Martonne Index. For both years, we measured δ 13 C signature in tree rings to calculate iWUE. Tree species richness had a positive effect on the response to drought both in terms of normalized ring width and iWUE, but only at a lower number of consociated species (