Nitrogen dynamics under corn fields in the Red River Valley of North Dakota

Abstract

AbstractExcessive applications of fertilizer N in corn (Zea mays L.) has profound environmental and economic consequences. Corn grain yield, N losses, N2O denitrification, NH3 volatilization, and soil water NO3 concentration at 60‐cm depth were collected for eight corn fields in the Red River Valley of North Dakota. Relationships of soil and management factors with cumulative N2O and NH3 losses were studied. Grain yield varied from 3.58 to 5.66 Mg ha–1. Cumulative NH3 and N2O losses were ranged between 1.0–2.4 kg ha–1 and 24.7–150 g N2O‐N ha–1, respectively. Soil organic matter (SOM; r = .94, p = .001), clay (r = .94, p = .001), and initial inorganic N (0–60 cm) content (r = .83, p = .01) had a positive relationship with cumulative N2O losses. Cumulative NH3 had a negative relationship with soil pH (r2 = .63, p = .01). Results indicate that soil properties such as, SOM, clay concentration, and initial profile N had a control over N losses.