Ecological processes and status assessment in coralligenous habitats

The coralligenous reefs are among the richest and threatened habitats in the Mediterranean Sea. They are the result of the interplay between the building activities and physical and biological eroding processes. In the Mediterranean Sea, dense populations of Paramuricea clavata shape animal forests characterising the seascapes of coralligenous habitats. After the general introduction, the abundance and composition of epibenthic assemblages inside and outside P. clavata forests were investigated across the Mediterranean Sea. According to this study, the gorgonian understoreys may enhance bioconstruction processes and increase resistance and resilience of the benthic assemblages in the coralligenous habitats. Mediterranean gorgonian are threatened by anthropogenic disturbances and mass mortality events. These events have often been linked to anomalies in the temperature profiles. A temperature-based surveillance tool was proposed by utilising oceanographic analysis and forecast models. Such a tool would allow for the timely study of mass mortality phenomena and the implementation of prompt restoration initiatives. The North Adriatic Sea hosts a large number of biogenic reefs. Computed Tomography has been used to analyse 3 and 12 years bioconstruction and bioerosion processes occurring in experimental tiles. The mean erosion rate increased with time, while the mean construction rate appeared to decrease. Experimental data combined with new technologies allow assessing the bioerosion and bioconstruction processes, which is a fundamental step towards the conservation of biogenic reefs. The need to assess the environmental quality status of coralligenous habitats and to fulfil the goals of the MSFD, suggest the opportunity to develop indices based on Citizen Science project that may support decision-makers in planning conservation strategies. The Reef Check Mediterranean Species Sensitivity (MedSens) index is proposed. MedSens index provides the mean sensitivity of the surveyed assemblages; helping to assess the environmental quality status and to identify the most likely disturbs acting in the study area.