Effects of residue removal and tillage on greenhouse gas emissions in continuous corn systems as simulated with RZWQM2

Agricultural production is a major source of carbon dioxide (CO2) and nitrous oxide (N2O) globally. The effects conservation practices on soil CO2 N2O emissions remain high degree uncertainty. In this study, under different residue tillage in an irrigated, continuous corn system, were investigated using the Root Zone Water Quality Model (RZWQM2). Combinations no/high stover removal (NR HR, respectively) no-till/conventional (NT CT, field experiments tested over four crop-years (Apr. 2011–Apr. 2015). model was calibrated NRCT, validated with other treatments. simulation results showed that volumetric water content (VWC) NR treatments (i.e., NRCT NRNT) 1.3%–1.9% higher than HR HRCT HRNT) averaged across years. A amount simulated years (annual average: 7034 kg C/ha/yr for 3.8 N/ha/yr N2O), lower HRNT 6329 3.7 N2O). long-term (2001–2015) suggested closely correlated (SRD), tillage, VWC, temperature (ST), management (Y), fertilizer application. Stover had cumulative emissions. annual 1st year from NRNT, 7.8%, 0.0%, 7.7% HRNT, respectively; then 15th 63.6%, 47.7%, 29.1% higher, respectively. Meanwhile, there no also demonstrated RZWQM2 promising tool evaluating practices.