The Technology
High frequency GPR is a non-destructive imaging technique using microwave/radar pulses, often from drones, to provide high-resolution soil subsurface information. GPR estimates soil depths and bedrock or other surfaces that restrict, redirect or concentrate water flow. Soil moisture content (SMC) variation is also accurately detected, useful for crop water use efficiency (WUE) evaluation. This advises irrigation aspects of precision agriculture programmes.
How it works
Electromagnetic waves are pulsed into the ground. The strength and time delay of the returning signal is measured to give information on soil properties. SMC, organic matter content, soil compaction and hard surfaces such as bedrock or drains which influence soil conductivity, affecting the GPR response.
Farmer / Agronomist benefits
Non-destructive mapping of farm soil profiles, usefully combined with GPS systems. Allows early irrigation planning and identification of compacted layers to direct subsoiler working depths, as well as helping to identify field drainage problems. GPR in itself does not identify the multiple factors combining to define SMC, which is where the historical grower and advisor field knowledge is needed.
Key Stakeholders (agriculture)
Monash University, Australia
iRed