Methods for measuring soil water content

Water has a significant influence on fundamental biophysical processes in the soil. It is one of the limiting factors for plant growth, which is why monitoring the water content in the field is particularly important in agriculture. In this article we present the methods currently used to measure the soil water content. We have described their functional principles, advantages, disadvantages and possible applications. Due to their widespread use in agriculture, we have focused on dielectric sensors, which are classified as electromagnetic methods. We have investigated the influence of soil properties on measurements with dielectric sensors and described possible methods for soil-specific calibration. In agriculture and environmental sciences, measurements of soil water content are particularly important for irrigation management. Irrigation based on measurements enables us to optimize the use of water resources and reduce the negative impact on the environment. For the correct functioning of such sensors it is necessary to check the suitability of the factory calibration function. Special attention is required when installing the sensors, as the presence of air gaps causes errors in the measurements.