The Interest Of Geophysical Methods For Locating Hydromorphic Horizons In Acid Pedological Systems

The aim of this study is to determine the interest of some geophysical methods, in particular Radio&IT in<br>locating hydromorphic horizons for acid pedological systems. Two areas were studied, one under forest, another in<br>an intensive agricultural site. A direct relationship between apparent resistivity and horizon type distribution was<br>established on the first site with a relative uniform soil depth. On the second site, soil depth and topsoil water<br>content explained most of the variations of the apparent resistivity, the influence of which was modelized by<br>multiple regression. Deviations from the regression model were then interpreted by taking into account the<br>succession of soil horizons. Results of Ground Penetrating Radar and Electrostatic Quadripole confirmed the<br>position of some of the limits between soils suspected by Radio-MT data. Finally, the prediction of hydromorphic<br>soil systems with the help of geophysical techniques is discussed.