Research Projects

Nitrous oxide (N2O) is one of the major greenhouse gases (GHG) generated from agriculture. It contributes approximately 3 percent of the total GHG inventory in California with an estimated 9 metric million tons of carbon dioxide (CO2) equivalent (MMTCO2E) emissions in 2006. There is great uncertainty in this estimation, however, because N2O emissions from agricultural soils are extremely variable, dependent on numerous environmental and agricultural management factors. Quantifying N2O emissions from California agricultural soils is vital to improving GHG emission budgets. Three ongoing projects, funded by the Air Resources Board (ARB), California Energy Commission (CEC), and California Department of Food and Agriculture (CDFA), are characterizing N2O fluxes in California cropping systems from synthetic nitrogen fertilizers. This study proposes to measure N2O emissions from cropping systems that receive dairy waste, another important source of nitrogen (N) in California. The project will provide N2O emission data from land-applied dairy waste sources and allow an estimation of baseline N2O emissions from Central Valley dairy systems. The result will be an improvement of the overall California N2O emission inventory.