SM150T User Manual 1.0
Appendix 1
42
Appendix 1
Soil-specific Calibration
This note provides details of 2 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 (
) is proportional to the refractive index of the soil (
) as
measured by the
SM150T
(see
Calibration
section).
The goal of calibration is to generate two coefficients (
a
0
,
a
1
) which can be used in a
linear equation to convert probe readings into soil moisture:
1
0
a
a
