MICROBIAL COMMUNITIES AND ALTERATION PROCESSES IN MONUMENTS AT ALCALA-DE-HENARES, SPAIN

Fungi belonging to the genera Altemaria, Penicillium, Phoma, Trichoder ma, Mucor, Ulocladium, Dictyodesmium and Phialostele colonize the buil ding materials of several monuments at Alcala de Henares (Madrid, Spai n). Bacteria of the genera Bacillus, Micrococcus and Thiobacillus were also isolated. Microbial activity in the surface layers of the stone was determined following the dehydrogenase activity test. Gypsum forma tion and weathering of some mineral components (e.g. feldspar, mica an d calcite) were shown by FT-IR and SEM-EDX, as well as an enrichment i n S due to air pollution and in P due to biological input.