The effects of chronic nitrogen deposition on atmospheric biomass burning emissions

This study examines how biomass burning emissions can be effected by regional air quality. An environmental chamber at the UC-Riverside Center for Environmental Research and Technology (CE-CERT) Atmospheric Processes Lab measured the properties of aerosols emitted from the burning of coniferous forest litter. Forest litter was collected from two sites of the San Bernardino Mountains Gradient Study in southern California: one site with high chronic nitrogen deposition rate and a site with low nitrogen deposition rate. The chemical and physical properties of the gas and aerosol-phase emissions were measured as a function of photochemical aging. Results indicate that there is a discernable compositional difference in the emissions from forest litter from an unpolluted (low NOx) environment as compared to a polluted (high NOx) environment. Fuel elemental analysis, NOx emission rates, aerosol volatility, and aerosol particle number distributions all differed significantly between the two sites.