Cyanobacteria attack rocks (CATS):Control and preventive strategies to avoid damage caused by cyanobacteria and associated microorganisms in Roman hypogean monuments

The CATS project focuses on the control, prevention and monitoring of cyanobacteria-dominated biofilms that cause damage to rock surfaces in Roman hypogea. It develops and integrates physical and biotechnological methods intended to limit the growth of microorganisms on valuable archaeological surfaces, and applies analytical methods to monitor the presence and the extent of the microbial damage. As in other hypogea, the development of biofilms is favoured by the limited air circulation, the even temperature throughout the year, and the high level of humidity. Biofilms composed of sciaphilous chroococcal and filamentous cyanobacteria associated with other microorganisms develop thanks to the light gradients that occur in the proximity of entrances and artificial lamps. Terrestrial cyanobacteria and associated microorganisms are the first colonisers of exposed lithic faces and their extensive development is supported by the mineral composition of the substrata and facilitated by the porous nature of the, mostly calcareous, surfaces