Skip to main content

Water quality of Ontario agricultural streams: defining nutrientconcentrations to prevent eutrophication

"inputs of nutrients (phosphorus, P, and nitrogen, N) to fresh waters  can cause excessive aquatic plant growth, depletion of oxygen, and  deleterious changes in abundance and diversity of aquatic  invertebrates and fish.  As part of a National Agri-Environmental  Standards Initiative?, the Government of Canada committed to  development of no-regulatory environmental performance standards that  establish nutrient concentrations to protect ecological condition of  agricultural streams.  Analysis of data from long-term provincial  monitoring programs and experimental studies in networks of 1 -15  streams showed that agricultural land use increase nutrient  concentrations in southern Ontario streams, resulting in increased  sestonic and benthic algal abundance, loss of sensitive benthic  macroinverebrate taxa, and an increase in benthic diatom taxa  indicative of eutrophication.  Calculation of provisional standards  for total P or total N using three empirical methods followed by  cross-calibration of these chemical standards with information on  biological condition resulted in recommendations for total P and total  N standards for agricultural streams in southern Ontario.  These  recommended standards should result in good ecological condition with  respect to benthic algal abundance, benthic diatom composition and  benthic macroinvetebrate composition.  Research is continuing to  determine whether these standards are protective of downstream  receiving waters and to evaluate interactions of nutrients with other  stressors (e.g., suspended sediments, pesticides), Specifically their  combined effects on aquatic food webs.  Note: this project is part of  a larger national study to determine the impacts of agricultural  activities on streams across Canada and to define nutrient  concentrations to protect aquatic life.

In progress
Start Date
End Date
Patricia ChambersPrincipal Investigator
Associated with 3 projects

Funding 13 projects for a total of $134,000.00

Funding 3 projects for a total of $1.00
Scope of Study
Field Investigation
Scale of Phenomena
Impact of Pollutants
Nutrients, Including Phosphorus
Lake Basin Connecting Channels
Lake Erie
Lake Huron
Lake Ontario
Lake St. Clair
Lake Superior
Annex Numbers
Control of Phosphorus
Remedial Action Plans and Lakewide Management Plans
  • Annex Numbers
    Annex Numbers
    Control of Phosphorus
    Remedial Action Plans and Lakewide Management Plans
  • Annex 17

The Great Lakes - St. Lawrence Research Inventory is an
interactive, Internet-based, searchable database created as a tool to collect and disseminate
up-to-date information about research projects in the
Great Lakes - St. Lawrence Region.