Calibration method for detection of matrix water content with dielectric-type moisture sensor

The physical and chemical properties of soil and substrate are different, so the moisture sensors can not be used directly for measuring the substrate moisture due to the great errors. To achieve rapid moisture detection of culture media, dielectric type EC-5 soil moisture sensor was used to make adaptive test with substrate in different proportions. The effect of temperature and bulk density on output value of the sensor was studied. And polynomial and linear regression methods were used to establish substrate moisture calibration models under the influence of temperature and bulk density. The experimental results demonstrated that the data from the EC-5 agreed reasonably well with the actual water content (R² > 0.9791). And the maximum average error was less than 13%. Therefore dielectric type EC-5 soil moisture sensor can be successfully used as the rapid detection equipment after calibration in this study.