2025/10/01 by Joshua P Mirabella, Adam C. von Haden, Gregg R. Sanford +2 · 1 voice
Agricultural and Biological Sciences · Environmental Science · #Crop Yield and Soil Fertility #Isotope Analysis in Ecology #Soil Carbon and Nitrogen Dynamics
paper · pdf · doi:10.1007/s00374-025-01946-w
openalex publication_date 2025/10/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
Abstract Understanding the fate of fertilizer nitrogen (N) in cropping systems is critical to improving agricultural sustainability and minimizing environmental losses. However, efforts to trace fertilizer N are often complicated by manure application in dairy cropping systems. We used a stable isotope tracing approach to investigate how different manure products influence the fate of synthetic fertilizer N in a Midwestern maize silage system by tracking 15 N-labled ammonium sulfate into crop biomass, soil organic matter fractions (particulate (POM) and mineral associated (MAOM)), and gaseous loss as nitrous oxide (N 2 O). Treatments included unprocessed liquid manure (LM), solid manure derived through chemical (CS) or physical (PS) separation, and a no-manure control (NM), combined with fertilizer rates of 90, 180, and 270 kg N ha −1 . Cumulative N 2 O emissions increased significantly with both manure application and higher fertilizer rates, with PS having lower emissions than LM following fertilizer application. Fertilizer contributed similar proportions to cumulative N 2 O emissions regardless of manure treatment. Total fertilizer N uptake by crops did not differ among manure treatments, but crops took up more fertilizer N at higher fertilizer application rates. Notably, application of CS and PS enhanced fertilizer N retention in the 0–15 cm soil MAOM pool compared to LM and NM. These findings highlight that although manure type does not significantly affect fertilizer N uptake by crops or fertilizer-derived N 2 O emissions, solid manures (i.e., CS and PS) can significantly increase fertilizer N retention in soils, offering potential benefits for long-term soil fertility and reduced N losses.