An electrical conductance method for determining condensation and evaporation processes in arid soils with high spatial resolution.

ABSTRACT We describe a new instrument developed to measure moisture movements as a result of condensation and evaporation processes in the upper soil layers in laboratory and field experiments. It is based on the well-known method of relating the moisture content of a soil to its electrical conductance. The high spatial resolution of 2 millimeters and the high sensitivity, especially in the dry range, make it a valuable tool for condensation and evaporation studies during the dry season of arid and semiarid climates, as well as for soil physical investigations of water vapor diffusion. A number of laboratory tests demonstrate the performance of the instrument.