Abstract
BackgroundA three-year field experiment was conducted to examine the responses of corn yield and soil nitrous oxide (N2O) emission to various management practices in middle Tennessee.Methodology/Principal FindingsThe management practices include no-tillage + regular applications of urea ammonium nitrate (NT-URAN); no-tillage + regular applications of URAN + denitrification inhibitor (NT-inhibitor); no-tillage + regular applications of URAN + biochar (NT-biochar); no-tillage + 20% applications of URAN + chicken litter (NT-litter), no-tillage + split applications of URAN (NT-split); and conventional tillage + regular applications of URAN as a control (CT-URAN). Fertilizer equivalent to 217 kg N ha-1 was applied to each of the experimental plots. Results showed that no-tillage (NT-URAN) significantly increased corn yield by 28% over the conventional tillage (CT-URAN) due to soil water conservation. The management practices significantly altered soil N2O emission, with the highest in the CT-URAN (0.48 mg N2O m-2 h-1) and the lowest in the NT-inhibitor (0.20 mg N2O m-2 h-1) and NT-biochar (0.16 mg N2O m-2 h-1) treatments. Significant exponential relationships between soil N2O emission and water filled pore space were revealed in all treatments. However, variations in soil N2O emission among the treatments were positively correlated with the moisture sensitivity of soil N2O emission that likely reflects an interactive effect between soil properties and WFPS.Conclusion/SignificanceOur results indicated that improved fertilizer and soil management have the potential to maintain highly productive corn yield while reducing greenhouse gas emissions.
Highlights
The United States (US) is the largest corn producer in the world, accounting for about 32% of the world's corn crop, with about 87.4 million ha in production in 2012 according to National Corn Grower’s Association (2013) [1]
Referring to the normal practice by farmers in middle Tennessee, we considered the treatment with conventional tillage + regular applications of aqueous urea ammonium nitrate (URAN-32-0-0 liquid N, 100%) as the control (CT-URAN)
Our results demonstrated that corn yield was significantly affected by no-tillage, with a higher value in the NT-URAN treatment (7.77 tones ha-1) than in the CT-URAN treatment (5.94 tones ha-1) (p
Summary
The United States (US) is the largest corn producer in the world, accounting for about 32% of the world's corn crop, with about 87.4 million ha in production in 2012 according to National Corn Grower’s Association (2013) [1]. To maintain high corn yield, large amounts of nitrogen (N) fertilizer are applied each year. Agricultural soil is the primary source of N2O and the average annual N2O emission from corn fields in the US ranges from 1 to 3.2 tons CO2 equivalent per hectare [4]. The annual total N2O emission from US corn croplands is greater than 29.4 million tons of CO2 equivalent [6]. Knowledge of the trade-offs between soil N2O emission, fertilizer management practice, and corn yield is essential for the development of sustainable landscapes and best management practices in these agricultural systems. A three-year field experiment was conducted to examine the responses of corn yield and soil nitrous oxide (N2O) emission to various management practices in middle Tennessee
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
