Erola Fenollosa1,2 and Sergi Munné-Bosch1
1Department of Evolutionary Biology, Ecology and Environmental Sciences, Faculty of Biology, Universitat de Barcelona, Barcelona, Spain
2Institute of Research in Biodiversity (IRBio-UB), Universitat de Barcelona, Spain
Although invasive species constitute one of the main threats to global biodiversity, key factors determining the changes that occur in a species along the invasion process and their magnitude are still unknown, hindering predictions of their expansion. One of the main climatic drivers determining plant distribution is temperature, as it is one of the main environmental variables limiting plant growth, and therefore may play a crucial role on determining species expansion across different environments.
In this study, our aim was to understand the expansion of the aggressive invader Carpobrotus sp. in Europe using an ecophysiological approach. For this reason, we contrasted the invasive and native ecological niche and explored experimental response to temperature of individuals from both ranges in terms of different physiological markers. The comparison of native and invasive niches revealed an invasive niche expansion towards colder climates. Moreover, individuals from different ranges showed differential mechanisms facing low temperatures in terms of their photoprotective response, mainly in the photosynthetic pigment degradation, increase on the de-epoxidation state of the xanthophylls and the accumulation of the lipophilic antioxidant α-tocopherol, where native individuals showed increased sensitivity to chilling. Carpobrotus sp. have a great adaptive capacity to low temperatures in its invasive range which may explain the observed invasive climatic niche shift to colder climates.