Monitoring of Marine Ecosystem Subjected to Infrastructrural Intervention

A multivariate statistical approach was used to assess the sediment quality in the coastal area between Torre Annunziata and the island of Capri in the Gulf of Naples (South Tyrrhenian Sea) during a four-year monitoring plan designed to monitor possible changes due to an infrastructure intervention related to the installation of a submarine power line. The unsupervised PCA model developed allowed to understand the evolution of the pollution over the years and to identify two different pressures on the area, one of a temporary nature related to the infrastructure works and characterized by a reduced pollution concentration caused by possible leaching phenomena due to the resuspension of sediments during the installation works, and the other one related to land-based pollution sources that persisted during the four monitored years independently of the infrastructure works. This approach allowed to understand the recovery time of the ecosystem and its ability to return to its original state after an infrastructure intervention, and to assess in a comprehensive way the distribution patterns reflecting the different pressure loads. Moreover, factors that govern the persistent effects of the pollution, such as organic matter and sediment textural characteristics, were identified and they were distinguished from those related to temporary disturbances associated with infrastructure interventions.