Résumé
This paper presents an experimental setup to study the SPAC (Soil-Plant-Atmosphere Continuum) and the mechanisms of water extraction by vegetation.The infiltration column was equipped with TDR probes and High-Capacity Tensiometers to monitor the profiles of volumetric water content and suction respectively. A balance was used to monitor the evaporation/evapotranspiration rate. Experiments were run in parallel on a bare sample and a soil sample vegetated with grass respectively. Two different evaporation/evapotranspiration regimes were imposed by considering natural and forced ventilation. The experimental setup was able to capture the transition from the energy-limited to the water–limited regime. The profiles of water content and suction recorded by TDR probes and the high-capacity tensiometers where coherent with the different stages in the evapotranspiration process. The response of the TDR probes has also been successfully validated by comparison with measurements of water content by oven-drying