Monitoring soil water content using IoT Time and Frequency Domain Reflectometry Sensors

Soil moisture is considered a crucial climatic parameter. Understanding and predicting variations in surface temperature, precipitation, drought, flood and the effects of future climate change need a thorough knowledge of soil moisture fluctuations. Furthermore, quantification of soil water content, one of the two variables that describe soil moisture, is essential to provide an accurate estimate of crop water needs, which is a crucial element in maximizing the effective use of water resources in agriculture. This study presents the development of an integrated monitoring programme of soil water content within the whole range of unsaturated zone using custom-made system that uses time and frequency domain reflectometry (TDR and FDR) probes to monitor complex hydrologic processes taking place in the unsaturated zone, including return flow to the atmosphere via evaporation, plant root uptake, and subsurface flow of groundwater. Signals logged by these sensors are recorded by an extensible and adaptable logging software component and are available both on premise and through a web application, facilitating their remote manipulation. For the purposes of this research a kiwi field was selected in the plain of Arta, which is located in the Epirus region, in the westernmost part of Greece. Acknowledgments: This research is part of the Project “e-Pyrros: Development of an integrated monitoring network for hydro-environmental parameters within the hydro-systems of Louros-Arachthos-Amvrakikos for the optimal management and improvement of agricultural production” (MIS 5047059) and received financial funding from the Operational Programme “Competitiveness, Entrepreneurship, and Innovation 2014-2020 (EPAnEK)”.