Soil heat storage and heat conductivity

Soil heat conductivity was previously measured with a stainless steel sonde attached with a thermoelement. The sonde is heated with 0.5 - 0.7 W power and the change in sensor temperature is followed. Three sensors were installed in pit 80 in the eluvial, illuvial and ground soil layers, and the sensors were connected to the Campbell 21X datalogger. The heat conductivity sondes were replaced 2011 and 2012 and replaced with four thermopile sensors (heatflux sensors, HPF01 or HPF01SC, HukseFlux). Thermopile measures differential temperature across the ceramics-plastic composite body. The temperature difference generates a small output voltage proportional to the local heat flux. In the soil heat capacity measurements separate thermoelement installed at a distance of 2 cm from the heated sonde. In the measurement the sonde is heated until a 0.5-1.0 °C is reached.