Table 2 Summary of the in-soil instrument’s specifications.

Soil heat flux

(SHF1, SHF1sc)

Campbell Scientific (Hukseflux) HFP-1

12

−2000 Wm⁻² to

2000 Wm⁻²

• Temperature dependence <0.1%/°C

• Thermal conductivity dependence 7%/(W/(mK))

• Non-stability <1%/yr

• Factory calibration uncertainty <3%

<0.1 Wm⁻²

Thermopile.

At 5 cm depth.

Campbell Scientific (Hukseflux) HFP-1SC

12

Soil temperature (ST)

Campbell Scientific TCAV

12

−40 °C

to

50 °C

Not reported

0.1 °C

Thermocouple.

At 5 cm depth.

Volumetric water content (VWC)

Decagon 5TM

12

0%

to

50%

<2% (VWC) after soil specific calibration.

0.08% (VWC)

Apparent dielectric permittivity (ADP).

At 5 cm depth.