Concentration-Discharge Relationship Controls on Phosphous for a River in a Cold Temperate Climate
Jane White, Nipissing University, [email protected]
April James, Nipissing University, [email protected]
Merrin Macrae, Univ. of Waterloo, [email protected]
Joel Harrison, North Bay-Mattawa Conservation Authority, [email protected]
Abstract
Estimating the contribution of phosphorus (P) entering source waters from tributaries during high-flow events is vital to P budgeting and management. Concentrations of phosphorus in the Wasi River, a tributary of Lake Nipissing located in the headwaters of Lake Huron, regularly exceed the provincial water quality objective, contributing to concerns over the occurrence of harmful algal blooms downstream in Callander Bay, a municipal drinking water source. Though P concentrations are lower during winter and spring freshet relative to other regions with similar climates, high-flow events such as spring snowmelt can contribute 80-90% of the yearly P loading from the Wasi River, which makes accurate estimation of these events vital to estimating larger time-scale P export. Calculating loading during snowmelt is challenging because these events are “open-ended”, making a discrete hydrograph difficult to establish. P sources can be depleted before the peak of the hydrograph during high-flow events, adding to the complexity of the concentration-discharge (C-Q) relationship. This study will add to, and analyze, data collected from the Wasi River over the last three years during high-flow events and base flow. Discussion will include characterization of C-Q relationships (Total Phosphorus and P species) considering seasonal, event size, and antecedent moisture controls.
1. Keyword
phosphorus
2. Keyword
tributaries
3. Keyword
climates
4. Additional Keyword
hysteresis
5. Additional Keyword
freshet
6. Additional Keyword
seasonality