Life History Trade-off Moderates Model Predictions of Diversity Loss from Climate Change
(English)Manuscript (preprint) (Other academic)
Climate change can trigger species range shifts, local extinctions and changes in diversity. Species interactions and differences in dispersal capacity are important mediators of community responses to climate change. The interaction between multispecies competition and differences in dispersal capacity has recently been shown to exacerbate the effects of climate change on diversity and to increase predictions of extinction risk dramatically. Differences in dispersal capacity, however, are part of a species' overall ecological strategy and are likely to trade off with other aspects of its life history that influence population growth and persistence. In plants, a well-known example is the trade-off between seed mass and seed number. The presence of such a trade-off might buffer the diversity loss predicted by models with random but neutral (i.e. not impacting fitness otherwise) differences in dispersal capacity.
Using a trait-based metacommunity model along a warming climatic gradient the effect of three different dispersal scenarios on model predictions of diversity change were compared. Adding random variation in species dispersal capacity (variable dispersal scenario) caused extinctions by the introduction of strong fitness differences due an inherent property of the dispersal kernel. Simulations including a fitness-equalising trade-off (trade-off scenario) based on empirical relationships between seed mass (here affecting dispersal distance, establishment probability, and seedling biomass) and seed number (fecundity) maintained higher initial species diversity and predicted lower extinction risk and diversity loss during climate change than simulations with variable dispersal capacity. Predictions including the seed mass - seed number trade- off were closer to predictions from models assuming uniform dispersal capacity (uniform dispersal scenario) than to models with random differences in dispersal capacity. Where climate change effects on large scale diversity patterns are of interest, the simplified assumption of uniform dispersal could therefore be the more cautious modelling choice.
Climate change, Dispersal, Life history trade-off, Seed mass - seed number trade-off, Plant metacommunity, Simulation modelling
Research subject Natural Resources Management
IdentifiersURN: urn:nbn:se:su:diva-133475OAI: oai:DiVA.org:su-133475DiVA: diva2:963140
FunderA multiscale, cross‐disciplinary approach to the study of climate change effect on ecosystem services and biodiversity