Wireless sensors facilitate plant growth

From the 1960s, high-yielding varieties of wheat spread quickly across Asia, followed by improved strains of rice. At the same time, farmers rapidly increased their use of mineral fertilisers, pesticides and irrigation. The gains were dramatic: over a period of 30 years, the volume of world agricultural production doubled. The ‘Green Revolution’ helped avert major food shortages and promoted rapid economic growth in China, South-East and South Asia.

But the revolution was not without its environmental cost. For example, in some regions, water was being pumped out of the ground for irrigation faster than it could be replenished. Second, widespread use of just a few high-yielding varieties of wheat and rice led to the loss of traditional varieties and increased vulnerability to pests and diseases. Finally, the misuse of fertilisers and pesticides sometimes outweighed their advantages.

Today, more sustainable agriculture techniques are in vogue. Chief among these is ‘precision agriculture’; the technology ensures ideal growth conditions by applying resources like water and fertiliser at the perfect time, significantly improving crop yields. In turn, precision agriculture enables growers to optimise resource use and minimise waste.

Precision agriculture depends on the IoT; the data used to determine the best time to water and feed plants comes from wireless sensors used to monitor soil conditions. One example is Canadian technology company Ginkgo Sustainability’s soil monitoring solution, SoiLiNQ.

Business intelligence lowers costs

The SoiLiNQ solution is made up of multiple SoiLiNQ Sensors powered by Nordic Semiconductor’s nRF52840 SoC and a SoiLiNQ Hub gateway. The SoC not only provides wireless connectivity between sensors and the gateway but also supervises the sensors and collates their data. The gateway is based on Nordic module partner Ezurio’s Sentrius MG100 Gateway2019 and is also supervised by the Nordic SoC. Data is transmitted via the gateway to the Cloud, where users can access it using the SoiLiNQ web application.

“Each SoiLiNQ sensor measures soil moisture, air temperature, humidity and other variables to create a detailed survey of the current conditions,” said Sean Militello, Director of Technology and Innovation at Ginkgo Sustainability. “Together, they provide a clear and accurate picture of environmental health. The solution provides our customers with transparent scientifically sound, actionable business intelligence that lowers their costs,” Militello said.

“Our goal is to allow more companies to enact and support sustainable practices. We also want to help the agriculture industry improve resource usage, crop quality and yields.”

Image credit: Nordic Semiconductor

Mitigating climate change

Analysis helps growers better understand their data to make informed decisions. It can also assist in mitigating the impacts of climate change by enabling growers to adapt crop treatment as weather patterns change. In the case of the SoiLiNQ web application, analysis is achieved using methods developed by the company’s academic partners.

Alpha testing of SoiLiNQ, using Ginkgo Sustainability’s third-generation sensors, was able to successfully collect and transmit detailed data about local environments.

“Based on these readings, our academic partners were able to confirm the accuracy of our methodologies for various types of [agriculture],” Militello said. “The web application was also able to accurately integrate sensor data with third-party environmental information, predicting soil moisture correctly 70% of the time.”

Militello explained that upcoming beta testing will use fourth-generation sensors, featuring improvements based on lessons learned from the alpha test. “Given the current performance of these new sensors in our labs, we expect the predictive accuracy of the system as a whole to improve by 12.5 to 15%,” he said.

Ultra-low power functionality

The sensors use a 3000 mAh battery, allowing them to remain in the field for at least 18 months before requiring a recharge, thanks in part to the ultra-low power consumption and fully automatic power management system of the Nordic SoC. Although the gateway typically runs using mains power, users can also purchase a Smart Power Selector Peripheral and a small solar panel. This set-up allows the device to switch to solar power when available, conserving energy.

Growing conditions can vary from field to field, but without detailed information, farmers are forced to manage all crops the same way. The result is varied yields across the farm. Precision agriculture, powered by networked wireless sensors, provides for fine-grained detail. That allows farmers to optimise growing conditions on a field-by-field basis. In this case the result is greater flexibility, enhanced yields and better use of resources.

Top image credit: iStock.com/SOMKID THONGDEE