New paper examines agricultural phosphorus surpluses in Ontario

A new paper reconstructs the agricultural phosphorus (P) inputs across the province of Ontario since the 1960s. The first author of the paper, entitled Agricultural phosphorus surplus trajectories for Ontario, Canada (1961-2916), and erosional export risk, is former ERG MSc student Tamara Van Staden. Co-authors include the ERG members Chris Parsons, Zahra Akbarzadeh, and Philippe Van Cappellen, as well as their colleagues Kim Van Meter and Nandita Basu. The results show the very high (>80%) retention of P in Ontario’s watersheds, implying the continued build-up of P legacies in agricultural areas. Because most legacy soil P resides in soils, we recommend that in order to reduce the risk of eutrophication, soil conservation should target high P input areas that are also vulnerable to erosion. The paper can be accessed at: https://www.sciencedirect.com/science/article/pii/S0048969721067930?via%3Dihub