Rebecca Ostertag

1 Introduction Islands support a disproportionate extent of global biodiversity, with exceptionally high rates of endemicity on remote islands (Carlquist 1974). Island biodiversity is among the most threatened and endangered, with invasive species posing a major threat to island floras (Fernández-Palacios et al. 2021).

1 Introduction Restoration activities are designed to meet diverse goals, commonly including native biodiversity, species complementarity, invasion resistance, ecosystem function and stability, food provisioning, and cultural services (Hallett et al. 2013). As a complement to traditional and Indigenous approaches, trait-based approaches are emerging as useful for species selection and monitoring of plants in restoration (Loureiro et al. 2023).

1 INTRODUCTION Although it has been argued that the coexistence of species in diverse communities can be explained by stochastic processes alone (Hubbell, 2001, 2005), examples of niche partitioning through the divergence of species in morphology, physiology, and life history in relation to heterogeneity of resource availability suggest that niche-based mechanisms are key determinants of plant species presence and abundance (Kitajima & Poorter, 2008; Liu et al., 2022; Russo et al., 2007;...