Measurement: Soil Suction
Generate detailed moisture release curves on undisturbed soil samples in a standard 250 mL sample ring, typically within a few days. HYPROP also determines unsaturated hydraulic conductivity values for the soil sample.
Water potential describes the force that drives water movement. It is the most fundamental and essential measurement in soil physics. Unfortunately, it's also a tricky thing to measure. The chart on the right (click on it to view the full image)…
The Vapor Sorption Analyzer (VSA) brings click and read efficiency to soil water characteristic curves. In 24 to 48 hours, the VSA generates up to 200 data points (water potential vs. water content) for both adsorption and desorption. The VSA works in the dry (-10 to -475 MPa) range. You can create automated soil-water characteristic curves and generate all the correlations with clay activity, surface area, and swelling potential. With the new static feature, you can hold humidity constant and look at the way soil takes up water into its crystal structure (2:1 clays) and monitor water content change over time.
Decagon's Soil Moisture Release Curve service uses UMS tensiometers and the HYPROP to produce the points for the moisture characteristic curve in the wet range, and the WP4C to produce the points in the dry range. Your soil moisture characteristic curve service is specific for the soils that you send to Decagon, and are over the range that you specify.