Los líquenes en un escenario de cambio global

Abstract

There is ample evidence of species distributional changes in response to recent climate change, mainly leading to a biodiversity reduction. It is equally clear that the response is species-specific. Most studies are species-biased towards better known taxons, and the inclusion "cryptic species" like lichens is needed for an integrated approach. Our ability to predict the nature and extent of species reaction to climate change, however, appears limited thus far. In this sense, the use of functional traits and ecological attributes might be helpful in order to improve the interpretation of predictive models. In this study, we have tested which lichen traits/attributes could be considered as drivers of climate change impact magnitude. We have calculated present and future distributions for 41 lichen species in the Iberian Peninsula, using ensemble climatic suitability maps (derived from GLM, GAM and CART models). We calculated 7 impact metrics as surrogates of climate change consequences on species distributions, and then tested traits/attributes effects on them. Forecasted distributions were species-specific and impacts were trait-mediated. Presenting smaller thallus size, being epiphyte and presenting green-algae biont provided protection against climate change. So they did rarity and small current distributions (ecological attributes). Surprisingly, we did not detect a significant effect of other lichen traits/attributes, so further research is needed in this sense. We also highlight the critical importance of the comparison of different metrics when assessing climate change impacts.