Edge of Field Modeling to Address Nutrient Management in Tile-Drained Agricultural Landscapes

The widespread conversion of low-gradient wetlands to farmable land using artificial drainage networks has led to unintended consequences of Harmful Algal Bloom (HAB) proliferation in the Western Lake Erie Basin and surrounding waterbodies. Recently, Kevin King (Research Leader at the USDA-ARS, Soil Drainage Research Unit in Columbus, Ohio) has established a series of edge-of-field (EOF) monitoring platforms across soil, management, and topographic gradients to quantify the impacts of practices on nutrient loadings in tile-drained landscapes. To date, 106 site years from 40 fields have been collected using a paired monitoring platform (Figure 1). A need exists to quantify pathways for nutrient delivery in surface and subsurface pathways at the EOF, inform sustainable management practices implemented by the farmers on the field, and assess the broader impact of EOF management on watershed nutrient budgets at broader spatial scales. The objectives of this proposal are to address current research needs by (1) building models for EOF monitoring sites, (2) develop subroutines to simulate BMPs and agronomic management strategies, (3) identify gaps in simulation tools and collect novel data to overcome limitations, and ultimately (4) determine optimal practices to simulate sustainable practices in the field in order to minimize nutrient loadings and concentrations at the EOF.