title: Dynamic Model Improves Agronomic and Environmental Outcomes for Maize Nitrogen Management over Static Approach.
abstract: Large temporal and spatial variability in soil nitrogen (N) availability leads many farmers across the United States to over-apply N fertilizers in maize ( L.) production environments, often resulting in large environmental N losses. Static Stanford-type N recommendation tools are typically promoted in the United States, but new dynamic model-based decision tools allow for highly adaptive N recommendations that account for specific production environments and conditions. This study compares the Corn N Calculator (CNC), a static N recommendation tool for New York, to Adapt-N, a dynamic simulation tool that combines soil, crop, and management information with real-time weather data to estimate optimum N application rates for maize. The efficiency of the two tools in predicting the Economically Optimum N Rate (EONR) is compared using field data from 14 multiple N-rate trials conducted in New York during the years 2011 through 2015. The CNC tool was used with both realistic grower-estimated potential yields and those extracted from the CNC default database, which were found to be unrealistically low when compared with field data. By accounting for weather and site-specific conditions, the Adapt-N tool was found to increase the farmer profits and significantly improve the prediction of the EONR (RMSE = 34 kg ha). Furthermore, using a dynamic instead of a static approach led to reduced N application rates, which in turn resulted in substantially lower simulated environmental N losses. This study shows that better N management through a dynamic decision tool such as Adapt-N can help reduce environmental impacts while sustaining farm economic viability.
authors.forename: Shai
authors.initials: S
authors.lastname: Sela
authors.forename: Harold M
authors.initials: HM
authors.lastname: van Es
authors.forename: Bianca N
authors.initials: BN
authors.lastname: Moebius-Clune
authors.forename: Rebecca
authors.initials: R
authors.lastname: Marjerison
authors.forename: Daniel
authors.initials: D
authors.lastname: Moebius-Clune
authors.forename: Robert
authors.initials: R
authors.lastname: Schindelbeck
authors.forename: Keith
authors.initials: K
authors.lastname: Severson
authors.forename: Eric
authors.initials: E
authors.lastname: Young
mesh_terms: D000383:Agriculture; D005308:Fertilizers; D009518:New York; D009584:Nitrogen / Q000737:chemistry*; D012987:Soil; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D003313:Zea mays
chemical_list: D005308:Fertilizers; D012987:Soil; D014874:Water Pollutants, Chemical; D009584:Nitrogen