INVERSE METHOD TO DETERMINE SOIL HYDRAULIC PROPERTIES FROM TRANSIENT OUTFLOW EXPERIMENTS

Transient outflow experiments coupling with an inverse method are promising to derive soil hydraulic information. The water retention curves obtained from one-step and multi-step outflow experiments were compared with those from the pressure cell method. We found that in one-step experiments the increment of pressure would reduce the non-uniqueness of inverse technique and that in multi-step experiment the combination of cumulative outflow with pressure head in the objective function would improve the final estimation and also reduce the non-uniqueness of inverse problem.