FUEL CHARACTERISTICS AND EMISSIONS FROM BIOMASS BURNING AND LAND-USE CHANGE IN NIGERIA

Nigeria is one of the 13 low-latitude countries that have significant biomass burning activities. Biomass burning occurs in moist savanna, d ry forests, and forest plantations. Fires in the forest zone are assoc iated with slash-and-burn agriculture; the areal extent of burning is estimated to be 80% of the natural savanna. In forest plantations, clo se to 100% of litter is burned. Current estimates of emissions from la nd-use change are based on a 1976 national study and extrapolations fr om it. The following non-carbon dioxide (CO2) trace gas emissions were calculated from savanna burning: methane (CH4), 145 gigagrams (Gg); c arbon monoxide (GO), 3831 Gg; nitrous oxide (N2O), 2 Gg; and nitrogen oxides (NOx), 49 Gg. Deforestation rates in forests and woodlands are 300 x 10(3) ha (kilohectare, or kha) and 200 x kha per year, respectiv ely. Trace gas emissions from deforestation were estimated to be 300 G g CH4, 2.4 Gg N2O, and 24 Gg NOx. CO2 emissions from burning, decay of biomass, and long-term emissions from soil totaled 125 561 Gg. These estimates should be viewed as preliminary, because greenhouse gas emis sion inventories from burning, deforestation, and landuse change requi re two components: fuel load and emission factors. Fuel load is depend ent on the areal extent of various land uses, and the biomass stocking and some of these data in Nigeria are highly uncertain.