University of Guelph researchers are studying the use of diversified crop rotations to reduce carbon emissions and help combat climate change. In the process, they’ve also come up with new, less expensive digital camera technology that could be used by agri-environmental scientists around the world.
“We’ve already accumulated a few years of carbon and water exchange data. Now we’re doing an analysis of agri-ecosystems – about whether and when they’re a carbon source or sink,” says Dr. Claudia Wagner-Riddle, a professor in the Ontario Agricultural College who studies climate change mitigation.
The project is funded by Food from Thought, Fertilizer Canada and the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) through the Ontario Agri-Food Innovation Alliance.
In an ongoing experiment at the Ontario Crops Research Centre in Elora, Ont., one field is managed conventionally with a corn-soybean-soybean rotation while another is managed with a corn-soy-wheat rotation using cover crops.
“It takes three years to get a complete cycle – we’re evaluating the net carbon use and the water cycle,” says Wagner-Riddle, a professor in the School of Environmental Sciences.
The team has completed two full years of its experiment.
The researchers added the sites to the PhenoCam Network, established in the U.S. in 2008 to track vegetation phenology (the progression of plants through the growing season) across North America and around the world. The network currently has more than 700 sites and contains 60 million images in its archive.
At Elora, a phenocamera at each site tracks the greenness of the crop canopy. The cameras take time lapse photos throughout the year that the team analyzes to assess the crop’s carbon exchange.
“In the future, people could use some of our data for more global analysis,” says Wagner-Riddle.
Advancing the technology
Each phenocamera typically costs about US$1,000. Dr. Shannon Brown, a post-doctoral researcher working with Wagner Riddle, came up with the idea of using a less expensive model.
“The cameras that we’re building are closer to $100 each,” says Brown.
The newly developed equipment includes a Raspberry Pi Zero W computer with a camera board, a case and an SD (secure digital) card. Raspberry Pi is a low-cost computer about the size of a credit card that takes the images and uses wi-fi to give other devices access to the data through web interface.
Early results from testing the cameras during a soybean growing season have been encouraging.
David Collins, a student working on the project from University College, Dublin, found that compared with the standard phenocam, the custom-built equipment yielded greenness chromatic coordinates (the degree of greenness in an image) that correlated slightly better with the net ecosystem exchange (how much carbon enters the atmosphere versus how much is removed).
After the researchers finish testing, they will install their cameras on each of the 18 lysimeters at Elora. Lysimeters are large underground cylinders encased in steel with sensors for monitoring soil water and nutrient budgets.
“While we’re currently focused on carbon flux, the technology could be used to gather data on a number of different things, including the water cycle and nitrogen use,” says Wagner-Riddle.
She says cheaper cameras used along with instructions posted on GitHub (an open-source repository for computer programmers) will help improve accessibility of data collection in agriculture and other sectors worldwide.