®

Lab vs. In Situ Soil Water Characteristic Curves—A Comparison

Lab-produced soil water retention curves can be paired with information from in situ moisture release curves for deeper insight into real-world variability.

The HYPROP and WP4C provide the ability to make fast, accurate soil moisture release curves (soil water characteristic curves-SWCCs), but lab measurements have some limitations: sample throughput limits the number of curves that can be produced, and curves generated in a laboratory do not represent their in situ behavior. Lab-produced soil water retention curves can be paired with information from in situ moisture release curves for deeper insight into real-world variability.

Moisture release curves in the field? Yes, it’s possible.

Colocating water potential sensors and soil moisture sensors in situ add many more moisture release curves to a researcher’s knowledge base. And, since it is primarily the in-place performance of unsaturated soils that is the chief concern to geotechnical engineers and irrigation scientists, adding in situ measurements to lab-produced curves would be ideal.

In this brief 20-minute webinar, Dr. Colin Campbell, METER research scientist, summarizes a recent paper given at the Pan American Conference of Unsaturated Soils. The paper, “Comparing in situ soil water characteristic curves to those generated in the lab” by Campbell et al. (2018), illustrates how well in situ generated SWCCs using the TEROS 21 calibrated matric potential sensor and METER water content sensors compare to those created in the lab.

Next steps

Questions?

Our scientists have decades of experience helping researchers and growers measure the soil-plant-atmosphere continuum. 

Presenter

Dr. Colin Campbell has been a research scientist at METER for 18 years following his Ph.D. at Texas A&M University in Soil Physics.  He is currently serving as Vice President of Environment. He is also adjunct faculty with the Dept. of Crop and Soil Sciences at Washington State University where he co-teaches Environmental Biophysics, a class he took over from his father, Gaylon, nearly 25 years ago.  Dr. Campbell’s early research focused on field-scale measurements of CO2 and water vapor flux but has shifted toward moisture and heat flow instrumentation for the soil-plant-atmosphere continuum.

Rapid, in situ Thermal Conductivity Measurements—Even in Moist Insulating Materials

Dr. Gaylon Campbell shows how to measure the thermal conductivity of wet insulation with a 5-minute read time. These previously impossible measurements are now possible through advanced electronics and analytical methods.
Webinars40 min watch

Combining in situ Soil Moisture with Satellite Data for Improved Irrigation Recommendations

How researchers are combining in situ, drone, and satellite measurements to extract key information and how these data can be connected across scales.
Webinars31 min watch

5 reasons you’re getting less accurate soil moisture release curves

In this 20-minute webinar, METER scientist Leo Rivera compares available methods and teaches how to combine the latest technology to generate full, accurate curves with hundreds of points in only a couple of days—instead of a couple of months.
Webinars40 min watch

Case studies, webinars, and articles you’ll love

Receive the latest content on a regular basis.