Could the intertidal Ellisolandia elongata reef be affected by climate changes expected in the near future in the Mediterranean Sea?

The concentration of Green House Gasses and specifically the concentration of CO₂ in the atmosphere is continuously increasing since the industrial revolution and it is the most relevant anthropic cause driving climate changes. Two of the strongest symptoms of those changes are the Global Warming and the Ocean Acidification which are progressively altering marine ecosystems and the populations of living organisms they support. The Mediterranean Sea is widely considered a 'laboratory basin' by suffering dramatic changes in its oceanographic and biogeochemical conditions derived from natural and anthropogenic forces. Calcifying seaweeds are the most important 'bioconstructors', from mesolittoral to circalittoral fringe, providing habitats and ecological niches for other species (i.e. biodiversity promoters) but also are good 'recorders' of the environmental condition they experience (i.e. biondicators). In this study we focused on the reef-forming Ellisolandia elongata from the Gulf of La Spezia (N-W Mediterranean Sea) by comparing the physical properties, growth rate and abundance of associated fauna in natural and experimental conditions (temperature and pH expected for 2050-2100). Four sampling sites were chosen in the intertidal zone. Reef samples were bring in the laboratory and put in experimental conditions for a month. Four aquaria simulated the actual conditions of temperature and pH, other 4 aquaria simulated temperature (+3°C) and pH (7.7) expected for the year near future. E. elongata grown in the natural and experimental conditions withstand mechanical stress in slightly different ways. The study of the effect of temperature and pH variations on growth rate and associated fauna of E. elongata reef is still in progress.