[en] The quantitative determination of the groundwater content is one of the most important preconditions for balancing the water flow in the soil. The effects of a non-homogeneous build up of the soil on the trickle behaviour can be followed up by regular measurement of soil humidity depending on the depth, and conclusions can be drawn on the transport movement of substances or harmful substances dissolved in water. Regular soil humidity measurements were carried out with the WALLINGFORD IH II sensor on a 200 metre long loess level and measurements of the soil deposit density were carried out by a γ-γ sensor to a depth of 5.6 m. The γ-γ sensor, a prototype specially developed for joint use with the WALLINGFORD sensor, was previously calibrated and the soil volumes measured by the two sensors were synchronized by calculation. The measurements from the neutron sensor were checked with gravimetrically determined groundwater contents from samples from the borehole at the measurement position and a calibration formula for loess profiles was determined. From the combined measurements of the two sensors, soil density profiles, porosity profiles, soil humidity profiles and profiles of groundwater saturation along the measured level were produced. (orig.)