DECISION-SUPPORT SYSTEM TO INTERPRET SOIL-MOISTURE SENSOR READINGS FOR CROP WATER MANAGEMENT

Efficient irrigation scheduling with soil moisture sensors requires pr oper interpretation of their readings. A computer-based decision suppo rt system was developed to facilitate sensor use and provide this inte rpretation for the farm manager. The system indicates whether to adjus t irrigation timing or amounts based on sensor readings and includes d iagnostics to flag sensors that may be faulty or may have been placed improperly. The system detects the bottom of the root zone by detectin g relative drying responses indicated by sensors placed at several dep ths. In this way, the system can adjust water amounts according to an expanding root system. Tests on a farmer-cooperator's field indicated potential improvements to the system. These include algorithms to bett er accommodate non-uniform application of water, and adjustment of con fidence levels in a water application recommendation as a function of the number of sensors placed.