A new McGill University study suggests that increasing crop diversity and shifting from annual wheat to perennial grain systems could improve soil health and strengthen agricultural resilience as climate change drives more variable rainfall patterns.
The research examined two cropping strategies at McGill’s Emile A. Lods Agronomy Research Farm in Ste-Anne-de-Bellevue, Quebec: intercropping through alternating rows of different crops and replacing annual wheat with intermediate wheatgrass, marketed as Kernza, a perennial grain gaining traction in niche food and beverage markets.
Researchers found both approaches altered soil microbial communities, which are critical to nutrient cycling, carbon storage and plant resilience. In particular, both systems increased populations of beneficial fungi linked to plant roots and reshaped the overall structure of microbial communities in the soil.
The study points to the importance of maintaining healthy soil biology as growers face more frequent weather extremes. Researchers noted that conventional monocropping systems can weaken microbial diversity over time, increasing vulnerability to drought and flooding.
The findings also showed that greater crop diversity led to more variability within microbial communities. Researchers said that variability may improve long-term adaptation by increasing the likelihood that some microbes are better suited to shifting environmental conditions.
To test the systems under climate stress, the research team used field shelters to reduce rainfall by 30% in some plots while redirecting that water to neighboring plots to simulate heavier precipitation. Soil samples were then analyzed for DNA and microbial activity to measure how communities responded to the changing moisture levels.
The work reflects growing interest in farming systems designed to improve resilience while reducing agriculture’s environmental footprint. Researchers said diversified and perennial cropping systems were historically used to reduce the risk of crop failure and maintain soil fertility before modern input-intensive farming became widespread.
The study adds to a growing body of research examining how alternative cropping systems could support long-term productivity as weather variability increases. Researchers said future studies will focus on how these systems perform over time under more extreme climate conditions.
Source: McGill University, "Crop diversity and perennial grains could strengthen soil health under climate stress, McGill study finds"