After decades in soil science research, Dr. Asim Biswas is familiar with the limitations of soil measurement. Measuring soil properties requires collecting soil samples and sending them for lab analysis, two processes that are both time-consuming and costly. Because of the cost and time barriers, farmers often do not sample their soil, or sacrifice in-depth sampling by sending in only one or two samples.
Innovative Approaches to Soil Management
Biswas, who is appointed as the Chair of Soils and Precision Agriculture with the Ontario Agricultural College and received the prestigious Steacie Prize for Natural Sciences, focuses on data-driven soil management, and most currently, on the creation of affordable, precise, and timely ways for farmers to generate and access data. Biswas is at the forefront of a growing movement to democratize the soil measurement process. The new approach optimizes sampling and sensor-based measurements for use in the field, making it affordable and time-efficient.
“If you go to the doctor, they want tests and scans [to see what] problem they’re dealing with. I started to do a similar approach [with] soil,” Biswas explains. The Biswas Soil Lab is approaching the challenge in two ways. First, the team is optimizing sampling to make the sample collection efficient and second, they are developing a sensor that will provide farmers with precise measurements of soil properties including soil carbon, a key metric of soil health.
The Role of Soil Carbon in Sustainability and Climate Regulation
Adequate soil carbon levels are important for nutrient cycling, plant growth, and soil stability. “We must manage [the soil] for today and for tomorrow because it’s a non-renewable resource. An inch of soil can take hundreds of years to form, so we should manage them well, efficiently, and sustainably. If we want to do that, we must know what and where they are. Better management is only possible through better measurement,” said Biswas.
Soils are also an important climate regulator: healthy soils absorb carbon from the atmosphere, creating a huge carbon sink. This drew the interest of the research funder, the Canadian Alliance for Net Zero Agriculture (CANZA), a national alliance that supports collaboration and innovation to achieve a net-zero agri-food system in Canada. Biswas’ research to revolutionize soil management practices through data driven approaches has also been substantially supported by Food from Thought and the Ontario Agri-Food Innovation Alliance, a collaboration between the Government of Ontario and the University of Guelph.
Harnessing Technology for Better Soil Management
To measure the carbon in the soil, Biswas’ team focuses on colour and near-infrared light waves as a means of estimating soil carbon, building off previous work on accessible soil analysis using a method called spectroscopy. The process uses a sensor to record the light waves passing through or reflected from a soil sample, registering a “soil signature” graph that can be read for information on soil characteristics, including soil carbon levels.
Dr. Hiteshkumar Vasava, Lab Manager at the Biswas Soil Lab, and PhD students Mojtaba Naeimi and Anshu Beri are training the model that analyzes the recorded sensor images. Using machine learning and artificial intelligence, the model links the image with its corresponding “soil signature” graph and generates results on soil carbon levels. These models are what allow the soil sampling method to work in the field, not just in the lab.
Light, in particular, has to be considered in the analysis process. Time of day, cloud cover, soil moisture, and regional location all influence the lighting of the images captured in the fields. A model that fails to account for these variations will generate less accurate results, which may lead to a different set of management decisions later on.
For farmers, Biswas says “[farmers] know the best. They are the keepers of their land.” Even so, soil data is crucial to aid the decision-making process, validating decisions normally made based on experience. For new farmers, who may lack that experience on a new plot of land, the tools Biswas is developing would provide a baseline reference for starting soil carbon management.
Learn More
Read Biswas’ correspondence on monitoring soil health recently published in Nature.
