A Fourier transform-Raman spectroscopic study of lichen strategies on granite monuments

The biodeterioration of granite by Lecidea fuscoatra (L) Ach,, Porpidia cin ereoatra (Ach,) Hertel & Knoph, and P. macrocarpa (DC.) Hertel & Schwab gro wing in the same environmental conditions has been studied by ruing Fourier transform-Raman spectroscopy Results were significantly different for the three species, with P. cinereoatra being the most active biodeteriorative l ichen. This lichen was also the only one in which calcium oxalate and gypsu m were identified spectroscopically. Physical disturbances to the substratu m were evidenced in all lichens studied by the incorporation of material, s uch as quartz and feldspar; into their thalli, but this phenomenon varied c onsiderably from species to species. The results indicate that lichen speci es can adopt different strategies and call have different biodeteriorative effects on granite, independently of environmental conditions and substrate .