USDA-NIFA ORG 2019 - 2022. Award# 2019-51106-30189. PI: Armen R. Kemanian Co-PIs: Felipe Montes, Jason P. Kaye and Ron Hoover. Funded by the USDA NIFA, this project seeks to use smart tillage to reduce N2O emissions from organic systems relying on incorporating manure and cover crops.

Our prior research shows that (N2O) emission is high when plowing legume cover crops or co-locating them with manure, and revealed that peak N2O emission are from denitrification and driven by hypoxic conditions caused by high respiration rates. The high availability of nitrate that drives denitrification losses also causes leaching. Organic agriculture and agriculture in general must control these harmful N losses, as acknowledged by stakeholders in our advisory board meetings. We propose smart tillage to creatively regulate the distribution and concentration of cover crop residues and manure residues in the plow layer.

We propose to control N2O emissions and N leaching by: diluting cover crops residue before inversion tillage, secluding manure from cover crop residues (by applying manure after cover crop burial), and by harvesting legume aboveground cover crop biomass when practical and when above a given threshold. Our project includes field-level manipulation and monitoring of biophysical variables controlling N2O emissions and N leaching, novel ways of monitoring O2 and CO2 concentration in the plow layer through imaging, and testing in producers' fields. Reducing N losses and preserving productivity is a priority for an environmentally friendly organic agriculture.