Appendix
⚫
63
Appendix
Soil-specific Calibration
This note describes two techniques for generating soil-specific
calibrations:
•
Laboratory calibration for substrates* and non-clay soils
•
Laboratory calibration for clay soils
* We use the term substrate to refer to any artificial growing
medium.
Underlying principle
Soil moisture content (
θ
) is proportional to the refractive index
of the soil (
) as measured by the WET150 (see How it works
on page 43)
The goal of calibration is to generate two coefficients (a0, a1)
which can be used in a linear equation to convert probe readings
into soil moisture:
+
=
1
0
a
a
