B11A-0412
Field Studies Show That In Situ Greenhouse Gas Emission Factors for East African Agriculture Are Less Than IPCC Values
Monday, 14 December 2015
Poster Hall (Moscone South)
David Pelster1, Klaus Butterbach-Bahl2, Mariana Rufino3, Todd S Rosenstock4 and George Wanyama1, (1)Organization Not Listed, Washington, DC, United States, (2)Karlsruhe Institute of Technology, Karlsruhe, Germany, (3)Center for International Forestry Research, Bogor, Indonesia, (4)World Agroforestry Centre, Nairobi, Kenya
Abstract:
Greenhouse gas (GHG) emissions from African agricultural systems are thought to comprise a large portion of total emissions from the continent, however these estimates have been calculated using emission factors (EF) from other regions due to the lack of field studies in Africa, which results in large uncertainties for these estimates. Field measurements from western Kenya calculating emissions over a year in 59 different sites found that GHG emissions from typical smallholder farms ranged from 2.8 to 15.0 Mg CO2-C ha-1, -6.0 to 2.4 kg CH4-C ha-1 and -0.1 to 1.8 kg N2O-N ha-1, and were not affected by management intensity. The lack of a response in N2O emissions to N fertilization suggests that the EF currently used in national inventories overestimates N2O emissions from typical smallholder agriculture. Another study measuring N2O and CH4 emissions from manure deposited by grazing cattle found that the N2O EF ranged from 0.1 to 0.2%, while the CH4 EF ranged from 0.04 to 0.14 Kg CH4-C per 173 kg animal. These suggest that the current IPCC EF overestimate agricultural soil and manure GHG emissions for Kenya, and likely for much of East Africa.
