Different sets of traits determine transition of alien species along the invasion continuum

Ruquia Gulzar; Maroof Hamid; Tabasum Hassan; Irfan Rashid; Anzar Ahmad Khuroo

doi:10.1016/j.scitotenv.2023.169137

Different sets of traits determine transition of alien species along the invasion continuum

Sci Total Environ. 2024 Feb 20:912:169137. doi: 10.1016/j.scitotenv.2023.169137. Epub 2023 Dec 8.

Authors

Ruquia Gulzar¹, Maroof Hamid¹, Tabasum Hassan¹, Irfan Rashid², Anzar Ahmad Khuroo³

Affiliations

¹ Centre for Biodiversity and Taxonomy, Department of Botany, University of Kashmir, Srinagar 190 006, Jammu and Kashmir, India.
² Department of Geoinformatics, University of Kashmir, Srinagar 190 006, Jammu and Kashmir, India.
³ Centre for Biodiversity and Taxonomy, Department of Botany, University of Kashmir, Srinagar 190 006, Jammu and Kashmir, India. Electronic address: anzarak@uok.edu.in.

PMID: 38070553
DOI: 10.1016/j.scitotenv.2023.169137

Abstract

Invasive alien species are currently considered as one of the dominant drivers of global environmental change. Till now, the majority of studies have focused on single or a few traits of alien species that facilitate their invasion. Also inclusion of all the traits which determine the transition of aliens along the different stages of invasion continuum (casual, naturalised and invasive) has remained largely overlooked. In this study, we collected a comprehensive trait dataset on 144 alien plant species of Kashmir Himalaya - a global biodiversity hotspot region. To test which traits of alien species, individually or in combination along with anthropogenic factors, determine their transition along the invasion continuum, we employed chi-square tests, boosted regression trees and phylogenetic methods. We found the perennial life span, longer residence time, greater number of introduced regions, and better seed dispersal mechanism were critical in determining the transition from casual to naturalised. The herbaceous growth form, therophyte Raunkiaer life-form, annual life span, achene fruit, longer residence time and broader introduced range were the species' traits determining transition from naturalised to invasive. Aliens introduced as ornamentals have more propensity to become naturalised; whereas aliens introduced unintentionally show overrepresentation at the invasive stage. Phylogeny alone showed mixed results indicating both clustering and dispersion; however, in combination with other traits, it plays a significant role in determining the stage of invasion. Overall, our study disentangles the individual and interactive roles of multiple traits that determine the transition of alien species' along the invasion continuum. Further, we foresee the potential applicability of our findings in designing robust invasion risk analysis protocols and stage-specific invasion management strategies in this Himalayan region, with learnings for elsewhere in the world.

Keywords: Invasion stage; Invasive species; Kashmir Himalaya; Management; Naturalisation; Phylogeny; Prediction.

MeSH terms

Biodiversity*
Ecosystem
Introduced Species*
Phylogeny
Plants
Seeds