Measured and Simulated Effects of Residue Removal and Amelioration Practices in No-Till Irrigated corn (Zea mays L.)

Authors

• Lidong Li, USDA, Agricultural Research Service, Lincoln, NebraskaFollow
• Liwang Ma, USDA, Agricultural Research Service, Fort Collins, ColoradoFollow
• Zhiming Qi, McGill UniversityFollow
• Quanxiao Fang, Qingdao Agricultural University
• R. Daren Harmel, USDA, Agricultural Research Service, Fort Collins, ColoradoFollow
• Marty R. Schmer, USDA, Agricultural Research Service, Lincoln, NebraskaFollow
• Virginia L. Jin, USDA, Agricultural Research Service, Lincoln, NebraskaFollow

Document Type

Article

Date of this Version

2023

Citation

European Journal of Agronomy (2023) 146: 126807

doi: 10.1016/j.eja.2023.126807

Comments

United States government work. Public domain

Abstract

Reducing nitrous oxide (N₂O) emissions to the atmosphere is expected to provide substantial climate mitigation benefits. Herein, we measured soil N₂O emission and crop yield responses in a nine-year, no-till continuous corn system under contrasting management practices including irrigation (full; deficit), corn stover retention (100 % retention; maximum mechanical removal), and cover crop use (winter cereal rye, Secale cereale L.; no cover crop). Field-measured data were used to construct a structural equation model (SEM_obs) to explore the causal effects of management on soil N₂O emissions. We also used the Root Zone Water Quality Model 2 (RZWQM2) to simulate management effects on soil N₂O emission. Structural equation modeling was used for the field-measured data (SEM_obs) and the RZWQM2 simulated data (SEM_sim) to quantify management relationships with soil and determine whether relationships observed in field data were captured by RZWQM2 simulations. Our experimental field results showed that stover removal decreased annual N₂O emissions compared to stover retention, only for deficit irrigated soil (2.83 ± 1.31 vs. 4.49 ± 3.65 kg N ha⁻¹ y⁻¹) and that deficit irrigation decreased annual N₂O emissions compared to full irrigation, only for soil with cover crops (3.31 ± 3.19 vs. 4.11 ± 3.80 kg N ha⁻¹ y⁻¹). The SEM_obs and SEM_sim results showed similar direction and magnitude of relationships between daily soil N₂O emissions and various management and environmental drivers. Our study improved the mechanistic understanding for the effects of agricultural management on soil N₂O emissions and can help reduce N₂O emissions from agricultural systems.