Matric Potential Sensor
The matrix potential , or water potential, is a measure of of how water moves in soil, and from soil to plants. Water potential is used to determine plant water availability and soil stress. Comparing soil water content and matric potential measurements, in situ moisture release curves can be created.
The Decagon Devices MPS-1 sensor measures the dielectric permittivity of an internal, porous ceramic disk to infer water potential. A large range of continuous soil water potential measurements can be made without calibration to specific soil types, since the dielectric permittivity of the porous ceramic disk is highly dependent on the amount of water that is present in the pore spaces of the ceramic.