An experiment using IoT to reduce water consumption in agriculture has seen a decrease by 75 percent in the water used to grow avocados.
The research was carried out by Kurt Bantle, farmer and senior solution manager at Spirent Communications. He has 900 young avocado trees planted in his “back garden” in Southern California. He decided to experiment into how avocados could be grown using less water through soil moist monitoring and automated irrigation.
Bantle divided his farm into 22 irrigation blocks and inserted two soil moisture measurement units into each block. The units contain a LoRa unit for narrow-band data communication to a LoRa gateway which has broadband cellular uplink connectivity functionality.
The gateway also contains a Spirent partner Oasis reprogrammable SIM which becomes the enabler in remote water provisioning. All soil moisture data is collected from the avocado trees into a cloud and visualised by a presentation layer.
When a tree needs to be watered, the solution turns the sprinklers on automatically to get the correct level of soil moisture for each tree. It then turns them off when the correct moisture levels are reached. The connected trees are monitored constantly day and night.
“Avocado trees typically take 4-acre feet (1-acre foot = 326000 gallons) of water per acre per year. This is not only to supply the needed water but also to leach the salts which build up in the soil,” said Bantle.
“The soil moisture sensors let me drastically reduce water usage by telling me when to water and how deep to water to push the salts past the bulk of the rooting zone. The majority of the roots are in the top eight inches of soil so there is a sensor there and one at 24 inches so I can see when I’ve watered deep enough to get the salts out of the rooting zone,” added Bantle.
“The case study showed water usage reduction by 75 percent, but the usage will climb as the trees get bigger. The goal is to reach a 50 percent reduction of water usage when fully grown. By keeping the salts in check along with keeping nutrients supplied, stress on the trees is reduced and they are able to have better crop production,” said Bantle.
IoT has its downsides too
The downside for Bantle in harnessing the power of IoT to reduce water consumption was that he was placed under state surveillance for meter tampering.
Corry Brennan, Globalstar regional sales manager at Simplex, told Internet of Business that IoT in agriculture will become more popular.
“The advantages of the ability to remotely track, monitor and then report on the condition of herd, couple with the ability to remotely gauge various other dependant factors such as soil quality introduces huge efficiencies for the modern farmer, they can be alerted to various scenarios in advance and save both time and money by not having to patrol and survey, using satellite technology to receive various information in a proactive fashion,” he said.