Life Cycle (LC) for Farm Manure at Egerton University, Kenya

by Daudi Mongeri Nyaanga (presenting author), Meshack Kipruto Korir, Patrick Wamalwa

Egerton University, Kenya


Farm manure is one of the main sources of global emissions of ammonia (NH3) and greenhouse gases (GHG). However, these emissions have not been successfully addressed hence there is need for intervention measures to abate the negative effect on the environment. This paper aimed at identifying and mapping farm manure emissions hotspots in Tatton and Ngongongeri farms of Egerton University, modeling manure handling processes from cradle to gate, quantifying and documenting emissions for decision making in manure management systems and policy formulation. Tatton and Ngongongeri farms were selected for the study. The mapping of the emission hotpots in the two farms was based on the available satellite imagery while the manure handling processes were model using umberto NXT universal software. The emissions from livestock manure were determined based on Tier 1 approach of IPCC and mathematical model for computing GHG emissions.The emission hotspots identified includedthe production units, biogas plant, lagoons and open fields. The open field manure emissions from dairy cows, sheep and goat for both farms were estimated at 5278, 262, 1646 MT/year, respectively. The emissions from pigs and poultry in a confined environment for both farms were 4195 and 456 MT/year, respectively. Data analysis showed no significant difference (P>0.05) in GHG emissions among the livestock sub-groups. NH3 emissions from dairy bio-slurry during storage and field application were approximated at 10 and 220 g/m3 whilefor carbon dioxide (CO2) at 27 and 0.9 g/m3, respectively. The CO2 equivalent emissions from the lagoons were estimated at 80 g/year. The quantification and documentation of emissions would be useful in decision making, provision of appropriate manure handling and management systems that lead to emissions reduction and environmental protection.