Emissions of N2O from the burning of biomass in an experimental system

Fifteen experiments were conducted in an open burning system to determine the amounts of N{sub 2}O produced from burning savanna grass (Venezuelan Trachypogon, Australian Sorghum intrans), straw, hay, oak, pine needles and litter of pine forest. Samples in stainless steel canisters were analyzed within one day after sampling in order to avoid artifact N{sub 2}O formation during storage. Emissions of N{sub 2}O were observed to be nearly coincident with the emissions of CO{sub 2} during the burning period for all the experiments. The amount of N{sub 2}O produced was dependent on the nitrogen content of the biomass. About 0.7% of the fuel nitrogen was oxidized to N{sub 2}O and most of the N{sub 2}O was formed during the flaming stage. Using the experimental data and the amounts of different types of vegetation burned globally per year, the authors estimate that about 2.7 {times} 10{sup 11} g of N{sub 2}O-N are produced per year from burning biomass, contributing only 2% to the global source of N{sub 2}O.