Internet of Things (IoT)-based precision irrigation with LoRaWAN technology applied to high tunnel vegetable production

Precision irrigation with sensor-based decision-making system has proven to be effective for water saving in crop production. Internet of things (IoT) system is necessary for monitoring the real-time data from sensors as well as automatically applying water. LoRaWAN, a new low-power wide-range network technology, is low-cost and easy to be implemented in IoT systems that can be used for precision crop irrigation. In this study, an IoT-based precision drip irrigation system with LoRaWAN technology was developed and evaluated for a vegetable high tunnel production system. Four irrigation management systems were designed and tested, including one based on volumetric soil water content sensors (SWC), two based on soil water potential sensors set to irrigate at different moisture thresholds (SWP#1 -30kPa and SWP#2 -60kPa, respectively) and a simple pre-set timer-based irrigation management system as a reference. Treatments were arranged according to a randomized complete block design with three replications. Sensor data were recorded and uploaded to an IoT platform (AllThingsTalk) for monitoring and irrigation control. Thresholds were determined for each irrigation strategy to start and stop the irrigation. The results indicated that the developed IoT system worked properly for the irrigation task.