Once upon a time in the south: local drivers of plant invasion in the harsh sub-Antarctic islands

• Main Authors: Bazzichetto, M., Massol, F., Carboni, M., Lenoir, Jonathan, Lembrechts, J.J., Joly, R., Renault, D
• Other Authors: Ecosystèmes, biodiversité, évolution Rennes (ECOBIO), Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Centre d’Infection et d’Immunité de Lille - INSERM U 1019 - UMR 9017 - UMR 8204 (CIIL), Institut Pasteur de Lille, Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille-Centre Hospitalier Régional Universitaire CHU Lille (CHRU Lille)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi Roma Tre = Roma Tre University (ROMA TRE), Ecologie et Dynamique des Systèmes Anthropisés - UMR CNRS 7058 UPJV (EDYSAN), Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS), Universiteit Antwerpen = University of Antwerpen Antwerpen, Institut universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.)
• Format: Report
• Language: English
• Published: HAL CCSD 2020
• Subjects: [SDV.BID]Life Sciences [q-bio]/Biodiversity; Antarctic; Possession Island; Antarc*
• Online Access: https://hal.science/hal-02942315; https://hal.science/hal-02942315/document; https://hal.science/hal-02942315/file/2020.07.19.210880v1.full.pdf; https://doi.org/10.1101/2020.07.19.210880

Aim: To investigate the local effect of environmental and human-related factors on alien plant invasion in sub-Antarctic islands. To explore the relationship between alien species features and dependence on anthropogenic propagule pressure to unravel key traits conferring invasiveness in the sub-Antarctic.Location: Possession Island, Crozet archipelago (French sub-Antarctic islands).Taxon: Non-native vascular plants (Poaceae, Caryophyllaceae, Juncaceae).Methods: Single-species distribution models were used to explore the effect of high-resolution topoclimatic and human-related variables on the occurrence of six of the most aggressive alien plants colonizing French sub-Antarctic islands. Furthermore, the interaction between alien species traits and their response to anthropogenic propagule pressure was analysed by means of a multi-species distribution model. This allowed identifying the features of species that were associated to low dependence on human-assisted introductions, and were thus potentially more invasive.Results: We observed two main invasion patterns: low-spread species strongly dependent on anthropogenic propagule pressure and high-spread species limited mainly by harsh climatic conditions. Differences in invasiveness across species mostly related to their residence time, life history and plant height, with older introductions, perennial and low-stature species being most invasive.Main conclusions: The availability of high-resolution data allowed for a fine understanding of the role of environmental and human-related factors in driving alien species distribution on sub-Antarctic islands. At the same time, the identification of alien species features conferring invasiveness may help anticipating future problematic invasions.