The aim of the course is to provide the students tools for understanding the diversity of biodeteriorations of Cultural Heritages, due to different organisms (bacteria, cyanobacteria, fungi, algae, lichens, hepatics, pteridophytes, plants). The knowledge of the biodiversity of organisms of different environmental compartments - air, water and soil -, of their ecology and adaptive strategies, is a basic skill for understanding their role in the biological deterioration and the strategy to counteract them.