Sticking around: plant persistence strategies on edaphic islands

Abstract

Species extinction risk at local scales can be partially offset by strategies promoting in-situ persistence. We explored how persistence-related traits of clonal and non-clonal plants in temperate dry grasslands respond intra- and interspecifically to variation in environmental conditions (soil, climate) and insularity. We focused on edaphic island specialist species, hypothesizing that plants experiencing harsh soil environments and strong insularity are distinguished by traits supporting enhanced persistence, such as small stature, long lifespan and resource-conservative strategies. We found general support for this hypothesis. Soil properties and insularity emerged as the most important drivers of trait patterns. However, clonal species showed more consistent responses to variation in environmental conditions and insularity than non-clonal plants, which were characterized by distinct species-specific responses. We call for a broader inclusion of persistence-related traits in plant ecology and biogeography; this may provide key insights for predicting species extinction risk in changing and insular environments.