Estimating PM10 emissions from spring wheat harvest using an atmospheric tracer technique

Particulate matter (PM) emission inventories are needed in order to assess the contributions from agricultural operations and to evaluate the impact of mitigation measures. Accurate emission factors, however, are crucial to develop reliable PM emission inventories. In this study, PM10 (PM with aerodynamic diameters less than 10 μm) emission factor for spring wheat harvest in eastern Ontario was estimated using a mobile source tracer technique. The tracer gas (N2O) was released from a point source moving along with a combine, and the ratio of N2O to PM10 concentrations was then used to estimate PM10 emission rate from the known release rate of N2O. The averaged PM10 emission rate for spring wheat harvest, estimated from the tracer technique was 0.58 ± 0.12 g s−1, which corresponded to an emission factor of 0.74 ± 0.12 kg ha−1. In addition, the capability of using the Industrial Source Complex (ISC3) model to back-calculate PM10 emission rate was also evaluated in this study. The averaged PM10 emission rate using the dispersion model was comparable to that from the tracer technique. The uncertainty in the determinations of PM10 emission rates using the dispersion model, however, was much higher than that using the tracer technique.