Modeling soil moisture from real-time weather data

Abstract

Extreme variability of rainfall during the growing season in the Prairies underlies the need to improve means of quantifying the amount of soil moisture available for plant growth in real time. This study was conducted to modify and validate the Versatile Soil Moisture Budget (VSMB) for estimating volumetric soil water content. A network of soil moisture hydra probes and weather stations were installed for continuous soil moisture monitoring and real-time weather data collection at 13 sites across Central and Western Manitoba during the 2009 and 2010 growing seasons. The data from the probes were validated and calibrated. Both the laboratory and field validations showed that the root mean square error of the default factory calibration increased with increasing clay content of the soil. Outputs from these probes were used to test the modified VSMB model. The model was most effective at simulating soil water content at the surface layers.