Location: National Soil Erosion Research Laboratory
Project Number: 5020-12130-004-023-I
Project Type: Interagency Reimbursable Agreement
Start Date: Sep 25, 2024
End Date: Sep 30, 2028
Objective:
Lake Erie is situated on the international boundary between the United States and Canada. Increasing magnitude and frequency of harmful and nuisance algal blooms, which are especially problematic in the shallow Western Lake Erie Basin (WLEB), have been linked with increasing dissolved phosphorus (P) loading from river tributaries (Stumpf et al., 2012; Jarvie et al., 2017; Ho & Michalak, 2017). Identifying both causes (Smith et al., 2015b) and solutions (Wilson et al., 2019) to increased dissolved P loading from this intensively drained and managed agricultural landscape is critical for meeting P reduction goals to address perennial algal blooms in Lake Erie (USEPA & Environment and Climate Change Canada, 2015).
Agricultural P losses may result from either recently applied fertilizers (incidental or new P; Withers et al., 2003) or from P accumulated in soil and sediments (legacy or old P; Kleinman et al., 2003). Identifying and partitioning sources of P in artificially drained landscapes is critical for meeting P loss reduction goals (Withers and Sharpley, 2008), as management strategies to decrease P loss will vary accordingly.
Approach:
Quantify sources of particulate P in subsurface tile drainage and the contribution of particulate P to legacy P losses.
Assess the potential for subsurface P release to tile drains due to reducing conditions.
Determine how tile drainage networks alter subsurface transit time distributions.
Develop a mechanistic crop nutrient uptake model for making more precise P application recommendations and predicting soil P drawdown.
