Determinación experimental del contenido en CO2 del suelo sobre una cavidad kárstica en clima mediterráneo (Cueva de Nerja, Málaga)

Abstract

The CO2 content and the temperature of the air have been measured within the scarce soil (although with relatively high organic matter concentration) which partially covers the carbonate outcrops over the Nerja Cave (Málaga). General yearly average values of around 850 ppm and 25 ºC have been identified, both using continuous recording devices and separated measures with portable equipment. Temperature evolution closely follows that of the outside atmosphere. Spatial variations in CO2 contents are related with the vegetal cover and with the soil depth. Seasonal variations are important, with a maximum of more than 1000 ppm in May (main vegetation development) and minimum (around 350- 500) in December. Daily oscillations have also been identified, ranging up to more than 600 ppm in the period of maximum CO2 production. These results agree with estimates based in hydrogeochemical modelling as well as in the TOC content of drip water to the cave