Effect of feeding practices and manure quality on CH4 and N2O emissions from uncovered cattle manure heaps in Kenya

Countries in sub-Saharan Africa (SSA) rely on IPCC emission factors (EF) for GHG reporting. However, these were derived industrialized livestock farms and do not represent conditions of smallholder (small, low-producing breeds, poor feed quality, scarcity). Here, we present the first measurements CH4 N2O emissions from cattle-manure heaps representing feeding practices typical highlands East Africa: 1) cattle fed below maintenance energy requirements to scarcity, 2) tropical forage grasses (Napier, Rhodes, Brachiaria). Sub-maintenance reduced cumulative manure compared receiving sufficient but did change EFN2O. affect or EFCH4. When grasses, differ between diets, EFN2O Brachiaria Rhodes diets lower than solid storage (1%, 2019 Refinement Guidelines). Manure grass diet when Napier Brachiaria, EFCH4 all three default (4.4 g kg−1 VS, Regression analysis revealed that N concentration C:N important drivers emissions, with low concentrations high reducing emissions. Our results show EFs overestimate excreta which calls additional develop localized systems SSA.