Corn Yield and Soil Nitrous Oxide Emission under Different Fertilizer and Soil Management: A Three-Year Field Experiment in Middle Tennessee.
BACKGROUND
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.


RESULTS
The 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.


CONCLUSIONS
Our results indicated that improved fertilizer and soil management have the potential to maintain highly productive corn yield while reducing greenhouse gas emissions.
College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America.
Qi
Q
Deng
College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America.
Dafeng
D
Hui
Climate Science Section, Illinois State Water Survey, Prairie Research Institute, University of Illinois at Urbana-Champaign, Champaign, Illinois 61802, United States of America.
Junming
J
Wang
College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America.
Stephen
S
Iwuozo
College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America.
Chih-Li
CL
Yu
College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America.
Tigist
T
Jima
Department of Viticulture and Enology, University of California Davis, Davis, California 95616, United States of America.
David
D
Smart
College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America.
Chandra
C
Reddy
College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, Tennessee 37209, United States of America.
Sam
S
Dennis
D000069599:Crop Production; D018556:Crops, Agricultural / Q000254:growth & development*; D005308:Fertilizers; D009609:Nitrous Oxide / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D013714:Tennessee; D014867:Water / Q000737:chemistry; D003313:Zea mays / Q000254:growth & development*
D005308:Fertilizers; D012987:Soil; D014867:Water; D009609:Nitrous Oxide