The Agricultural Research Service (ARS) of the USDA works to determine the effectiveness of various conservation practices by monitoring changes in nutrient losses from fields over time. This type of research is often referred to as "edge-of-field" monitoring since it characterizes nutrients, including phosphorus, leaving the field. The ARS participates in Conservation Effects Assessment Project (CEAP) and, as an extension of CEAP, operates an extensive network of edge-of-field monitoring sites.

The ARS publishes peer-reviewed papers to evaluate conservation practice standards across the Western Lake Erie Basin (WLEB) in conjunction with more focused field-scale assessments. The research helps determine how, when, where, and what nutrients are transported from fields to tributaries and, ultimately, Lake Erie. This research allows the impact of management strategies to be quantified and helps drive agricultural conservation in a sustainable direction.