Caracterización microambiental en sistemas kársticos someros (Cueva de Altamira, Cantabria)

Résumé

In order to achieve a continuous record of the microclimate of Altamira Cave (Cantabria, Spain), an automatic minitoring system, measuring air temperature, CO„ 222Rn, relative humidity, etc., has been installed. Cave air temperature is fairly homogeneous, with values ranging from 13.25QC to 14.85-C throughout the year. A phenomenon of thermal inversion between both indoor and outdoor temperature in relation to the thermal inertia of the hostsrock, is observed. The highest (near 6000 ppmv) and lowest (300 ppmv) CO, concentrations are recorded in autumn and summer respectively. The period of lowest CO, concentration coincides with the lowest values in 222Rn concentration, and atmospheric pressure stability period and the maximum difference between indoor and outdoor temperature. The later is a determinant parameter in gaseous exchange between karst and exterior atmosphere. The impact of visitors, provoking an increase in air temperature, CO, concentration and relative humidity was found to enhance hostrock microcorrosion.