Methane uptake in soils of southern Spain estimated by two different techniques: Static chamber and (222)radon flux and soil air concentration profiles

Measurements of methane fluxes from four differing soils in the surroundings of Malaga (Spain) were carried out by two methods: a direct method using a static accumulation chamber at the soil surface and an indirect method obtained from simultaneously measured Rn-222 flux from the soil surface in parallel with the concentration profile measurements of Rn-222 and CH4 in the air of soil. The directly measured methane flux at all the investigated soils was higher than the methane fluxes derived from the indirect method. Atmospheric methane was consumed by all the soils and mean direct flux to the atmosphere were 3.25 mu mol m(-2) h(-1). The study showed no correlation between methane uptake and soil temperature, which might be due to the dry conditions prevailing during the study period.