Leaf trait variability in Mediterranean forest endemics and their divergence from widespread species: a study of 45 taxa and 26 congeneric pairs

Cristina Gasperini ¹, Federico Selvi ¹, Roberto Canullo ², Elisa Carrari ¹, Stefano Chelli ², Andrea Coppi ¹, Giannantonio Domina ³, Emmannuele Farris ⁴, Alfredo Maccioni ⁴, Francesco Mascia; Nicola Postiglione; Leonardo Rosati ⁵

Department of Agriculture, Food, Environment and Forestry, Applied and Environmental Botany, University of Firenze, Firenze, Italy ¹, School of Biosciences and Veterinary Medicine, Plant Diversity and Ecosystem Management Unit, University of Camerino, Camerino, Italy ², Department of Agriculture, Food and Forest Sciences, University of Palermo, Palermo, Italy ³, Department of Chemical, Physical, Mathematical and Natural Sciences, University of Sassari, Sassari, Italy ⁴, Department of Chemical, Physical, Mathematical and Natural Sciences, University of Sassari, Sassari, Italy; School of Biosciences and Veterinary Medicine, Plant Diversity and Ecosystem Management Unit, University of Camerino, Camerino, Italy; School of Agricultural, Forest, Food and Environmental Sciences, University of Basilicata, Potenza, Italy; ⁵

Why endemic species have restricted range size while others, including closely related taxa, have more widespread distribution has been widely discussed, but is still a central issue in ecology and biogeography. Today, it is well established that a variety of historical, ecological, and biological factors can result in a limited dispersal capacity and a restricted distribution range. The Mediterranean flora is especially rich in narrow-ranged endemic species, of which a non-negligible proportion is typical of forest habitats. Recently, Selvi et al. (2023) provided baseline statistics for over 130 forest taxa endemic to Italy, highlighting the currently poor knowledge about their functional characteristics and ecological strategies. Leaf traits play a critical role in plant growth and survival and are essential to understanding the functional space explored by plants in terms of resource use (Wright et al. 2004; Garnier et al. 2015; Niinemets 2020; Niklas et al. 2023 ). Exploring the functional side of leaves of narrow-ranged endemics can thus provide insights into their resource acquisitive vs. conservative strategies and competitive abilities. In the PRIN project Forendemics context, we focused on key leaf traits in 45 endemic taxa, either herbaceous or woody, sampled across several Italian peninsular and insular regions (one population per species). This allowed us to determine the range of interspecific variability, the position of each taxon within the global leaf economic spectrum as well as their ecological strategies in the CSR scheme. To address the leaf functional divergence to related widespread taxa, we included the trait analysis of 20 congeners of similar forest habitats, resulting in 26 phylogenetically independent contrasts of endemic-non-endemic species pairs. Geographical and environmental variables for each sampled endemic species/population were also accounted for to test their effects on the variation of each trait. Results of these analyses allowed us to advance our understanding of the leaf functional characteristics of narrow-ranged forest endemics, and to test the hypothesis that endemics are mainly characterized by conservative-related traits, such as low SLA and high LDMC, reduced competitive ability and enhanced stress tolerance.

Main author career stage: Postdoc / Fellow

Contribution type: Poster

First choice session: 3. Biodiversity and global change

Second choice session: 2. Ecology