Plant Invasion Decreases the Likelihood of Community Persistence Through Asymmetric Competition.

Plant invasion is a significant driver of species loss in ecological communities. However, projecting its impact on multispecies coexistence remains a challenge. Here, we conducted pairwise experiments with five native and five non-native species, using the Ricker model to estimate interaction coefficients and population growth rates. We assessed the impact of non-native species on community persistence potential through a structural approach that integrates multispecies interactions and estimates coexistence probabilities. We found that community persistence potential generally declined after invasion, with the feasibility domain (i.e., the probability that all species co-occur simultaneously) becoming more asymmetric as more native species were replaced by non-native ones. Interestingly, non-native species were more likely to be excluded first under random environmental perturbations in communities where they were dominant. Our findings highlight the importance of clarifying species interaction structure under random disturbances in shaping community persistence and suggest tailored invasion management strategies to optimise resource allocation.