A new study conducted by a team of researchers from Manitoba and Saskatchewan has found that a widely used fertilizer essential for global food production could potentially harm nearly half of the freshwater bodies in the Canadian Prairies.
The fertilizer, urea, is heavily relied upon by about two-thirds of the world’s population for food cultivation. Despite its widespread use, there has been limited research on the impact of urea on aquatic environments.
In the research experiment, scientists added urea to farm ponds in Saskatchewan to emulate the effects of agricultural fertilization in the southern Prairies. The results showed a significant increase in the growth of microscopic algae, leading to oxygen depletion in the ponds.
The excessive presence of algae in water bodies due to fertilizer runoff can have detrimental effects, including fish mortality, toxin exposure, and harmful algae blooms. This phenomenon could push freshwater ecosystems to a critical point, as stated by Cale Gushulak, an assistant professor at the University of Manitoba.
Comparisons with various water bodies in southern Saskatchewan indicated that decades of urea usage could potentially degrade almost half of the region’s lakes, wetlands, and reservoirs. The study also highlighted similar vulnerabilities in agricultural regions in China and the United States.
While the study emphasizes the need for better fertilizer management practices, Gushulak suggests that completely halting urea use is not a viable solution. Improving technology and agricultural practices to prevent fertilizer runoff into water bodies is crucial to safeguarding freshwater ecosystems.
Asim Biswas, a professor at the University of Guelph, acknowledges the study’s significance but emphasizes the need to consider interactions between urea and existing phosphorus levels in water bodies. He cautions against overstating the impact of urea on entire ecosystems and urges a balanced perspective to avoid causing unnecessary alarm.
Gushulak underscores the importance of addressing the issue of high phosphorus levels in conjunction with urea contamination, especially in shallow Prairie water bodies. The study’s findings challenge the perception that Canada has abundant freshwater resources, highlighting the need for proactive measures to protect water quality amid changing climate patterns.
Continued infiltration of urea into freshwater systems could exacerbate water quality issues and escalate resource management challenges in the future. Gushulak warns that as climate conditions evolve, uncertainties in water availability may pose additional risks to water security and ecosystem health.