Data for Fertilizer Management and Environmental Factors Drive N2O and NO3 Losses in Corn: A Meta-Analysis

lt;pgt;The specific aim of this meta‐analysis project was to determine the impact of 4R N management techniques on nitrous oxide (Nlt;subgt;2lt;/subgt;O) and nitrate (NOlt;subgt;3lt;/subgt;) losses relative to corn yield. The team collected and synthesized field research data published prior to July 2014 that measured N losses as affected by 4R fertilizer N management (right rate, source, timing, and placement) in North American corn‐based cropping systems.lt;/pgt;

lt;pgt;Core ideas from the paper include: 1) Systematic review and meta-analysis demonstrate key factors for reducing agricultural N losses. 2) Nitrification inhibitors and side-dress fertilizer N each reduce Nlt;subgt;2lt;/subgt;O losses by ~30%. 3) Temperature controls Nlt;subgt;2lt;/subgt;O emissions and precipitation controls NOlt;subgt;3lt;/subgt; leaching losses. 4) Higher levels of soil carbon reduce NOlt;subgt;3lt;/subgt; losses, but increase Nlt;subgt;2lt;/subgt;O emissions. 5) Lack of simultaneous data for Nlt;subgt;2lt;/subgt;O and NOlt;subgt;3lt;/subgt; impedes understanding of tradeoffs and synergies.lt;/pgt;

lt;pgt;This data publication includes all observations (management, crop response, and N loss details; for each treatment-site-year) used in meta-analysis models. The dataset contains 789 observations (417 with Nlt;subgt;2lt;/subgt;O losses and 388 with NOlt;subgt;3lt;/subgt; losses) with up to 72 variables each.lt;/pgt;

lt;pgt;The Data Dictionary describes all variables. Because parts of the dataset have been updated/corrected since publication of the journal article, the Data Dictionary also includes notesamp;nbsp;that detail specific dataset modifications needed to reset a small number of variables to the status used in the meta-analysis models (in order to reproduce the exact regression models from the publication).lt;/pgt;