Nitrogen inputs best predict farm field nitrate leaching in the Willamette Valley, Oregon.

ABSTRACT: Nitrate leaching is an important yet difficult to manage contribution to groundwater and surface water contamination in agricultural areas. We examine 14 farm fields over a four year period (2014-2017) in the southern Willamette Valley, providing 53 sets of annual, field-level agricultural performance metrics related to nitrogen (N), including fertilizer inputs, crop harvest outputs, N use efficiency (NUE), nitrate-N leaching and surplus N. Crop-specific nitrate-N leaching varied widely from 10 kg N ha^-1yr^-1 in hazelnuts to >200 kg N ha^-1yr^-1 in peppermint. Averaging across all sites and years, most leaching occurred during fall (60%) and winter (32%). Overall NUE was 57%. We used a graphical approach to explore the relationships between N inputs

SUBMITTER: Compton JE 

PROVIDER: S-EPMC8318121 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature