Greenhouse gas emission factors recorded by the international body for the assessment of climate change are at least two to ten times higher than the actual estimates from livestock waste in Kenya.
For a long time, African countries have relied on default emission factors provided by the UN Intergovernmental Panel on Climate Change (IPCC), to develop strategies on reductions of greenhouse gas (GHGs) emissions. This is because there are very limited GHG measurements from cropping and livestock systems in most developing countries. However, there has been a growing concern on the applicability (or lack thereof) of data from IPCC to sub-Saharan African agricultural systems, and the subsequent development of mitigation interventions that may not be tailored to these systems.
Recognising this, stakeholders in climate change in Africa including scientists and policy makers have voiced the need to develop region specific emission factors; to aid in the development of cross-sectoral long-term mitigation strategies specific to East Africa.
Part of the research at the International Livestock Research Institute (ILRI) focuses on understanding and managing the environmental footprint of livestock. At ILRI’s Mazingira Centre, this research aims to provide accurate context-specific information on the environmental impacts, particularly on nutrient cycles and GHG emissions of current livestock production systems, to enable predictions of intensification in these systems, and opportunities to mitigate GHG emissions
David Pelster, a scientist at the Mazingira Centre, highlights that one of the biggest gaps in understanding how to mitigate these impacts in Africa is a lack of baseline data.
We have no information on how much greenhouse gas emissions occur due to agriculture on this continent; almost all the emission factors used in the modelling studies [used to predict emissions from agriculture] are based on studies conducted in North America, Europe and Australia and these emission factors are likely incorrect. Said Pelster (read interview here)
In an important first for Kenya, research from the Mazingira centre has generated GHG data measured and analysed for Kenya in Kenya.
A new study carried out by scientists at the ILRI’s Mazingira Centre measured GHG emissions from livestock waste in Kenya, targeting two common breeds of cattle- the native Boran and the exotic Friesian. The study sought to establish the GHG emissions from livestock manure and to find out if diet affects the emissions in any way. Cattle were fed on different diets, consistent with those frequently used on smallholder farms in the region.
A recently published paper based on the study- ‘Methane and nitrous oxide emissions from cattle excreta on an East African grassland’ reveals that GHG emission factors recorded from the African livestock waste are at least ten times lower than calculations based on the simplest level of IPCC methods and data, Tier 1.
Diet and type of breed are some of the factors that influence GHG emissions from livestock waste. The paper records that low-quality feeds result in poor quality manure that produces low emissions. However, improved quality feeds are not synonymous with increased emissions. The study established that supplementation of cattle diet with Calliandra calothyrsus – a leguminous fodder tree promoted as a feed supplement- significantly reduced the methane emissions from cattle feces.
Access the paper here
For further information about the study and Mazingira Centre, contact Lutz Merbold (L.Merbold[at]cgiar.org) and David Pelster (D.Pelster [at] cgiar.org).