Effects of Tillage and Residue Removal on Soil Nitrous Oxide Emissions and Corn Yield.

Long-term residue removal and no-tillage practices in continuous corn (Zea mays L.) systems may alter important chemical and physical soil properties and influence gaseous nitrogen (N) losses. A 3-yr study (2015-2017) was conducted to investigate the effects of tillage and residue management on soil nitrous oxide (N₂O) emissions and crop yield in continuous corn in Urbana, Illinois. Treatments included chisel plowing as conventional tillage (CT) and no-tillage (NT), with either residues fully removed (RR) or retained (R), representing four treatments total. Preliminary results from 2015 and 2016 show opposite trends occurred each year. In 2015, conventional tillage plus residue retained produced the lowest cumulative and yield-scaled N2O emissions as well as the second highest yields. However, in 2016 both no-till treatments resulted in cumulative and yield-scaled N2O emissions that were lower than conventional tillage plus residue removed which produced the highest N2O emissions. However, yields for no-till plus residue retained were also the lowest in 2016. In both years, conventional tillage plus residue removal contributed to the highest cumulative and yield-scaled N2O emissions while also maintaining among the highest yield relative to other treatments. Results from 2017 will be combined with the first two years of data to determine if any consistent relationships are observed over the study period.