Format: ORAL

Sergio Muriel1, Isabel Martnez1, Gregorio Aragn1, Pilar Hurtado1 2, Mara Prieto1

1 Área de Biodiversidad y Conservación, Universidad Rey Juan Carlos, Móstoles, Madrid, Spain 2 Dipartimento di Farmacia (DIFAR), Università degli Studi di Genova, Genova, Italia

It is known that environmental variables affect functional diversity in terricolous lichen communities from gypsum soils. And although these observed responses of functional traits in relation to environmental changes may be due to species turnover and/or intraspecific trait variation (ITV) it is not known until what extent ITV and species turnover influence the observed trait variability. In order to understand how these communities survive under challenging conditions we aim to analyze the effect of environmental and soil variables on intraspecific trait variation (ITV) and species turnover and which is the contribution of both processes to functional variability. For this purpose, we quantified the relative contribution of species turnover and ITV determining the functional variation in lichen communities from gypsum soils in Spain and analyzed the relation with climate and edaphic predictors. We surveyed 35 plots along a latitudinal gradient and measured a set of eleven quantitative functional traits potentially affected by climatic and edaphic conditions and related to water use strategy, photosynthetic performance, and nutrient uptake. The results showed that ITV explained most of the functional changes in lichen communities along the latitudinal gradient except in the water holding capacity which had a similar relative contribution of both ITV and species turnover. Interestingly, climatic variables barely affected most traits except in the case of the nitrogen content and traits related with water use strategy were mostly affected by gypsum content. These results suggest that lichen communities confront environmental conditions (mostly gypsum content) by adjusting their trait values within the species rather than by the replacement of species.