A FIELD SYSTEM FOR AUTOMATICALLY MEASURING SOIL WATER POTENTIAL

This paper describes a system that will automatically read soil tensiometers. The system uses a vacuum transducer on each tensiometer whose output voltage varies linearly with the amount of tension in the tensiometer. A datalogger is programmed to scan the transducers at selected intervals and record the information on cassette tape. The information is then transferred to a large computer for calculations and plotting of soil water potential with time. The system is battery-operated, weatherproof, and suitable for use under field conditions.