ABSTRACT
ABSTRACT: The presence of biological crusts on stone walls of Neolithic temples in the Mediterranean region determines a protective role against physical-chemical weathering, such as rain, wind or thermoclastism, despite their long consideration as a biodeteriorating agent. The bioprotection of biological crusts lasts after the death of organisms, as crusts of deposited substances remain. The role of biological crusts on soils has a different view, as their main role is binding soil particles. The disappearance of those crusts increases the release of dust, water run-off and reduces rain infiltration. Their loss can drive into a dismantlement of walls, as soils disaggregate. Any change in environmental conditions will modify growth conditions (light, water, temperature) and would determine the loss of biological crusts. Their disappearance would increase the risk of deterioration of the heritage and lead to aesthetical changes.
