From raised garden beds under hydro corridors to apartment building roofs, researchers at the University of Toronto say urban agriculture may hold the keys to improving access to different types of food in large cities while reducing greenhouse gas emissions.
"Urban areas have so much food-growing potential, but our knowledge about how, where and what kind of crops can be grown in and around cities is limited," says Marney Isaac, a professor in the department of physical and environmental sciences and the department of global development studies at U of T Scarborough.
"We know even less about how well urban agriculture can capture and store carbon dioxide, a greenhouse gas that is a major contributor to climate change."
To help answer these and other questions, Isaac will lead a multifaceted project with a team of researchers and partners from the private and public sector called TOsustain (Toward Sustainable Urban and Peri-urban Agriculture for Net-zero Food Systems). It is being supported by a $3.9-million grant from the NSERC- and SSHRC-funded Sustainable Agriculture Research Initiative.
The first task is to create an inventory of current and potential land for agriculture in urban and peri-urban (the land immediately surrounding urban areas) spaces across Greater Toronto. This includes smaller farms and large-scale growing operations, public lands, hydro corridors, community gardens, green roofs and unused green spaces.
The project will also look at measuring the amount of greenhouse gas (GHG) emissions urban agricultural land can potentially trap and store and identifying farm management practices that can reduce GHG emissions. It will also include research that looks at regulations and policies that either constrain or promote urban agriculture, and develop a model to estimate GHG emissions from urban agriculture.
Isaac says there may be other benefits, too.
She points to the added security of having to rely less on food imports - not to mention the additional emissions created by the need to ship it around the world.
"The majority of our food is imported, so there's a huge security element," says Isaac, who is an expert on making agriculture more sustainable.
"This really came to light during the pandemic. If we can do more to localize food production and enhance crop diversity, it can help make our food system more resilient."
The researchers also want to explore how sustainable agricultural practices - those that require less intensive use of fertilizers, pesticides and irrigation - in urban areas can help reduce GHG emissions compared to conventional agricultural systems. Isaac adds that greater urban food production might also help reduce the pressure on converting forests to farmland in rural areas, a major environmental concern and contributor to climate change.
The project brings together an interdisciplinary team of 15 researchers, including 11 from U of T, with expertise in soil biogeochemistry, crop biology, microbial ecology and urban food systems, among others. It also includes eight partner organizations from the private and public sectors that are involved in food production, food distribution and land management.
Adam Martin, an assistant professor in U of T Scarborough's department of physical and environmental sciences and project co-lead, says urban farming isn't about replacing large-scale agricultural systems that supply wheat, for example. Rather, he says it can produce relatively large quantities of fruits and vegetables that can bring economic benefits to urban households.
Martin adds that improving access to food in urban areas has a host of positive downstream effects.
"Local food banks rely heavily on local small-scale farms and community gardens for fresh produce, and food bank use is on the rise," he says, noting that many urban communities are located in so-called "food deserts," where the cost of accessing certain food, particularly fresh produce, is much higher than in other communities.
"By increasing people's access to nutritious and affordable food, it can go a long way in addressing these social and economic challenges."