Colonization and deterioration processes in Roman mortars by cyanobacteria, algae and lichens

The mortars covering some walls of the Roman city of Baelo Claudia (Cadiz, Spain) support an abundant colonization of cyanobacteria, algae and lichens. The distribution of these organisms is closely related to microclimatic parameters. Furthermore, the development, specific composition and biomass of algal cryptoendolithic communities are related to the wall orientation. The effect of these communities on mortar deterioration is discussed.This was a contribution from the Cooperation Agree- ment between the Consejería de Cultura, Junta de Andalucía and the C.S.I.C.: Estudio diagnosis de los conjuntos y yacimientos arqueológicos de la Comu- nidad Autónoma Andaluza en su contexto geomorfo- lógico, biológico y climático.Peer Reviewe