ECB-WQ: A Long-Term Agroecosystem Research (LTAR)-Eastern Corn Belt node field-scale water quality dataset.

The Eastern Corn Belt (ECB) node of the Long-Term Agroecosystem Research (LTAR) network is representative of row crop agricultural production systems in the poorly drained, humid regions of the US Midwest and a significant focus for addressing water quantity and quality concerns affecting Lake Erie and the Gulf of Mexico. The objectives of this paper were to (1) present relevant background information and collection methodology, (2) provide summary analyses of measured data, and (3) provide details for accessing the dataset and discuss potential database applications. The ECB-water quality (ECB-WQ) database is comprised of hydrology and water quality data from three privately owned farms in Northwest Ohio and Northeast Indiana and is available for download through the United States Department of Agriculture Ag Data Commons. The dataset includes information on site characteristics (drainage area and soil type), field management (fertilizer application, planting rate, and yield), and daily discharge and measured nutrient concentrations from surface and subsurface tile drainage outlets. Discharge and water quality vary widely across the ECB and are paramount to developing innovative management strategies that balance crop production goals with environmental targets. Discharge is generally greater from subsurface tile drainage compared to surface runoff. Phosphorus concentrations are typically greater in the surface runoff compared to tile drainage, while nitrogen concentrations are greater in subsurface tile drainage. The ECB-WQ database was developed to better facilitate understanding of water quantity and quality within this unique, systematic, artificially tile-drained region and is critical for understanding implications of field management practices, quantifying environmental and production processes, constraining hydrology/water quality models, and informing future water quality policies.