"MINOR" CULTURAL HERITAGE AS MONITORING TOOL FOR ENVIRONMENTAL AND ANTHROPIC IMPACT IN THE CITY OF VENICE

Air quality and climate significantly impact outdoor cultural heritage, accelerating degradation phenomena such as erosion, detachment, and biological growth. This project aims to use “minor” cultural heritage, including small statues, reliefs, and coats of arms that adorn the historical centre of Venice, to evaluate urban decay trends related to the city's environment, aiding the municipality in prioritizing interventions. Recent and archival photographs were compared to evaluate the decay evolution of these heritage items over time. In situ Raman spectroscopy analyses were used to detect degradation products occurring on the heritage. Art-Risk 1 methodology was used to assess the vulnerability of 30 selected heritage, and the Art-Risk 5.0 Atlas allows to correlate degradation patterns with the climatic hazard characteristics of the Venetian environment. Despite the observed decrease in black crusts on several heritage, related to the reduced presence of SOx compared to the past, gypsum was still detected by Raman spectroscopy analyses. 14 of the 30 heritage items selected for vulnerability assessment exhibited high vulnerability indices, indicating severe to poor conditions. The influence of various factors (distance from canals, orientation, exposure) is under investigation. Additionally, the use of QGIS Geographic Information System allows to visually emphasize the main degradation forms occurring on Venetian heritage. In conclusion, this study correlates degradation patterns with the climatic characteristics of the Venetian environment, creates geo-localized impact maps to distinguish between climatic and anthropogenic contributions to degradation, highlights the most affected areas, and identifies potential decay trends in buildings.