A recent study conducted by a team of researchers from Manitoba and Saskatchewan has revealed that a widely used fertilizer essential for food production is causing significant degradation in nearly half of the freshwater bodies across the Canadian Prairies.
Urea and other nitrogen-based fertilizers are relied upon by about two-thirds of the global population to grow food, as highlighted by Cale Gushulak, an assistant professor at the University of Manitoba’s biological sciences department and a participant in the study. Despite this reliance, there has been limited research on the impact of urea on aquatic environments.
To assess the effects of agricultural fertilization in the southern Prairies, researchers from the University of Manitoba and University of Regina conducted an experiment where they introduced urea into farm ponds in Saskatchewan. The results showed a substantial increase in the growth of microscopic algae, leading to oxygen depletion in the ponds.
Gushulak emphasized that the overflow of fertilizer into water bodies is causing severe water-quality issues, with detrimental consequences such as fish mortality, elevated toxin exposure, and harmful algae blooms. The study suggests that nearly half of the lakes, wetlands, and reservoirs in the Prairie region may have been negatively impacted by decades of urea usage.
The research also indicated that agricultural areas in China and the United States face similar vulnerabilities due to urea application. Gushulak stressed the importance of implementing improved fertilizer technologies and management practices to prevent the contamination of freshwater bodies.
While acknowledging the significance of the study, Asim Biswas, a professor at the University of Guelph, cautioned that urea’s impact in water is influenced by existing phosphorus levels. He suggested that the interaction between urea and phosphorus could vary in different ecosystems and that generalizing the findings might be an exaggeration.
Gushulak highlighted that most Prairie water bodies naturally contain high levels of phosphorus, making them susceptible to urea-induced effects. He noted that while not all water bodies worldwide may experience extreme consequences, many agricultural regions with fertile lowlands and shallow waters could be at risk.
The study challenges the perception of Canada as a water-rich country, pointing out that water quality issues are prevalent both domestically and globally. Gushulak warned that continued infiltration of urea into freshwater systems could lead to deteriorating water quality and increased costs for water usage, especially as climate patterns in the Prairies evolve.
In conclusion, the study underscores the urgent need for sustainable agricultural practices to safeguard freshwater ecosystems and ensure water security for future generations.