Coupling X-ray microtomography and macroscopic soil measurements: a method to enhance near saturation functions?

Agricultural management practices influence soil structure, but the characterization of these modifications and consequences are still not completely understood. In this study, we aim at improving water retention and hydraulic conductivity curves using both classical soil techniques and X-ray microtomography in the context of tillage simplification. We show a good match for retention and conductivity functions between macroscopic measurements and microtomographic information. Microtomography highlights the presence of a secondary pore system. Analysis of structural parameters for these pores appears to be significant and offers additional clues for objects differentiation. We show that relatively fast scans supply not only good results, but also enhance near saturation characterization, making microtomography a highly competitive instrument for routine soil characterization.