Modeling Impacts of Visitation on Cave Environments

Abstract eng:
Wall paintings of the Mogao Grottoes have survived for a millennium in the cool-dry cave environment in the northwestern desert of China. Visitor numbers have been steadily increasing, subjecting the wall paintings to greater stresses contains hygroscopic salts. The largest threat to the wall paintings is elevated humidity levels near or above their deliquescent humidity, 67% RH, of the salt. The carbon dioxide (CO2) concentration, an indoor air quality (IAQ) parameter, was set not to exceed 1500 ppm in the caves for visitor comfort and safety. Two mathematical models, one for CO2 concentration and the other for humidity, were developed for simulating the environment in caves. The models use known CO2 and moisture emission rates for adults, measured air infiltration rates of the caves, and climate conditions of the caves and site. Predicted values and monitored data were compared over the 8-hour operational period as well as closed overnight. The CO2 concentration coincided well indicating the validity of the model. However, the humidity prediction was nearly 200% above the monitored peak as well as equally faster decay rates, indicating lack of the buffering term, such as the adsorption/desorption of moisture by cave surfaces.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket