Niche variation in endemic Gentiana ligustica between two biogeographical regions

Davide Casalino ¹, Ian Briozzo ¹, Chiara Bonifazio ¹, Maria Guerrina ¹, Luigi Minuto ¹, Gabriele Casazza ¹

Dipartimento di scienze della terra, dell'ambiente e della vita, Università di Genova ¹

Gentiana ligustica is an endemic species of the Southwestern Alps growing on calcareous rocky grassland, in Alpine and Mediterranean biogeographic regions. Populations in the Mediterranean region are at the warm margin of the species distribution and their conservation status is assessed as “Inadequate”, and the global warming could further negatively affect these populations. The aim of this research is to compare the microenvironmental conditions used by the species in the two biogeographical region investigating plant community and soil. In five sites for each biogeographical region, we performed three floristic relevés in 2x2m plots and we collected three soil samples. We identified alliances and we associated Ellenberg Indicator Values (EIV) to each species to investigate microclimatic conditions. Kruskal-Wallis test and PCA were performed to explore differences between the biogeographical regions. Gentiana ligustica is more abundant in sandy, low depth soils with low nutrients and the soil conditions are similar between the two biogeographical regions. PCA based on EIV shows low differences between the two biogeographical regions, although Mediterranean populations grow under higher variety of ecological conditions. Nevertheless, Alpine populations select significantly higher light intensity. Our results suggest that, despite low differences in microclimatic preferences, Mediterranean populations select shade environment. Further studies on differences in reproductive ecology between the two biogeographical regions will be performed to develop proactive strategies for the conservation species.

Main author career stage: PhD student

Contribution type: Talk

First choice session: 2. Ecology

Second choice session: 3. Biodiversity and global change