Influence of temperature on soil water content measured by ECH 2O-TE sensors

Abstract

The aim of this study was to investigate the influence of temperature on water content value measured by ECH 2O-TE sensors. The influence of temperature on measured soil water content values was clearly demonstrated. Soil water content values measured during the day apparently oscillated with oscillating soil temperatures. Average daily temperature and soil water content were calculated for selected periods. Regression relationships between deviations of soil temperature and soil water content from their daily average values were evaluated. Correlation between the soil water content and temperature deviations increase with the soil depth due to the lower influence of rainfall and evaporation at the soil surface on measured soil water content values in deeper soil layers eg soil water content oscillation was controlled mostly by oscillating temperature.The guideline values of linear regression equations (R 2>0.8) were very similar, close to value 0.002 and the intercept values were equal to zero. The equation for recalculation of measured soil water content values at given temperature to reference soil water content for reference soil temperature, was propozed on the basis of this analysis. © 2012 Institute of Agrophysics, Polish Academy of Sciences.