Using airborne thermal inertia mapping to analyse the soil spatial variability at regional scale
Résumé
This study aims at demonstrating the ability of thermal airborne remote sensing to help in delineating soil types over large areas. Measurements of the surface temperature variations were compared with electrical resistivity measurements recorded for three depths of investigation. The study area was located in the Beauce region with Calcisols and Cambisols, 0.3 to 1.2 m thick. Airborne thermal measurements were recorded by the ARIES radiometer in the 10.5-12.5 fJm thermal infra-red channel, on Oecember 11th 2002. Comparisons between thermal airborne data and electrical resistivity measurements demonstrated that: the spatial organisation of the thermal inertia map resembles the spatial organisation of the 0-170 cm resistivity map, suggesting that the investigation depth of the two methods is similar; the thermal inertia values were significantly different between the Calcisols and the Cambisols. In the Beauce area, the thermal inertia map would then consist of a useful tool to characterize the soil spatial variability with a high spatial resolution.