Rapid upwards spread of non-native plants in mountains across continents

Evelin Iseli , Chelsea Chisholm , Jonathan Lenoir (1) , Sylvia Haider (2) , Tim Seipel (3) , Agustina Barros (4) , Anna Hargreaves , Paul Kardol , Jonas Lembrechts (5) , Keith Mcdougall (6) , Irfan Rashid (7) , Sabine Rumpf (8) , José Ramón Arévalo (9) , Lohengrin Cavieres , Curtis Daehler (10) , Pervaiz Dar , Bryan Endress , Gabi Jakobs (11) , Alejandra Jiménez , Christoph Küffer , Maritza Mihoc (12, 13) , Ann Milbau , John Morgan , Bridgett Naylor , Aníbal Pauchard , Amanda Ratier Backes , Zafar Reshi , Lisa Rew , Damiano Righetti , James Shannon , Graciela Valencia , Neville Walsh , Genevieve Wright , Jake Alexander

1 EDYSAN - Ecologie et Dynamique des Systèmes Anthropisés - UMR CNRS 7058
2 Institute of Biology, Geobotany and Botanical Garden
3 MSU - Montana State University
4 CONICET-IANIGLA - Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales [Mendoza]
5 Universiteit Antwerpen = University of Antwerpen [Antwerpen]
6 NSW DPI - New South Wales Department of Primary Industries
7 University of Kashmir,
8 University of Vienna [Vienna]
9 ULL - Universidad de La Laguna [Tenerife - SP]
10 UHM - University of Hawai‘i [Mānoa]
11 ETH Zürich - Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich]
12 Institute of Ecology and Biodiversity and Department of Ecological Sciences
13 Universidad de Concepción - University of Concepcion [Chile]

Abstract High-elevation ecosystems are among the few ecosystems worldwide that are not yet heavily invaded by non-native plants. This is expected to change as species expand their range limits upwards to fill their climatic niches and respond to ongoing anthropogenic disturbances. Yet, whether and how quickly these changes are happening has only been assessed in a few isolated cases. Starting in 2007, we conducted repeated surveys of non-native plant distributions along mountain roads in 11 regions from 5 continents. We show that over a 5- to 10-year period, the number of non-native species increased on average by approximately 16% per decade across regions. The direction and magnitude of upper range limit shifts depended on elevation across all regions. Supported by a null-model approach accounting for range changes expected by chance alone, we found greater than expected upward shifts at lower/mid elevations in at least seven regions. After accounting for elevation dependence, significant average upward shifts were detected in a further three regions (revealing evidence for upward shifts in 10 of 11 regions). Together, our results show that mountain environments are becoming increasingly exposed to biological invasions, emphasizing the need to monitor and prevent potential biosecurity issues emerging in high-elevation ecosystems.

Domaines: Sciences de l'environnement

Evelin Iseli, Chelsea Chisholm, Jonathan Lenoir, Sylvia Haider, Tim Seipel, et al.. Rapid upwards spread of non-native plants in mountains across continents. Nature Ecology & Evolution, 2023, ⟨10.1038/s41559-022-01979-6⟩. ⟨hal-03969878⟩