Water potential is a measurement that may not be as intuitive as soil moisture content, but is still very useful. Soil moisture, or volumetric water content is a measure of how much water by volume is in a given soil or substrate. Water potential is the amount of energy required to access that water, defined as a suction measurement.
Soils and substrates are all unique in the way they bind water in the soil or substrate pores, salts and other materials they are composed of. Because of this, it is possible to have two substrates that are both equal parts water by volume, but the accessibility of that water be different. For instance, in a sandy substrate the water may flow easily through, while in a clayey or “spongy” substrate the water is bound.
The MPS-6 measures water potential in terms of suction (kPa) from-9 to -100,000 kPa with a resolution of ±10%.
- ACCURACY ±(10% + 2 kPa) from -9 to -100 kPa; Soil Temperature: ±1 °C
- RESOLUTION 0.1 kPa; 0.1 °C
- RANGE -9 to -100,000 kPa; -40 °C to 60 °C
- EQUILIBRATION TIME 10-60 minutes, depending on soil type or media
- CABLE LENGTH 5 m; longer cables available upon request.
- SENSOR DIMENSIONS 9.6 cm x 3.5 cm x 1.5 cm