The Anaerobic Biodegradation Model (ABM): A flexible tool for predicting methane emission from livestock manure

Publikation: KonferencebidragPosterForskningpeer review


Methane emission from livestock manure contribute significantly to the climate footprint of agriculture. The current IPCC approach for estimating methane emissions from stored livestock manure employs emission factors related to annual or monthly temperature and volatile solids in excreta, which offers little flexibility for most effects of storage management alternatives and manure characteristics or treatments. To accurately predict methane emissions at a farm level a more comprehensive model is needed.
We present a new microbial model that tracks organic matter flow and conversion through combined hydrolysis and fermentation, followed by methanogenesis via multiple methanogen populations with different temperature optima. These features allow the model to predict methane emission dynamics in response to short- and long-term changes in temperature and other variables. Inhibition of methanogens by pH, ammonia, and hydrogen sulfide is included based on previously described responses. A population of sulfate reducers competes with methanogens for substrate.
The model is available as an R package from The package provides a tool that can reflect management (e.g., manure removal frequency, washing of manure pits, manure production rate, surface area, and acidification) and environment in ways that have been shown to be important in experimental studies of CH4 emission during manure storage. This can be used to understand processes leading to gas emission and guide the selection of mitigation technologies.
As a demonstration, selected model parameters were fitted to a comprehensive dataset from a pig facility with continuous methane emission measurements over 350 days. The ABM was then used to predict methane mitigation potential of management practices, including frequent manure removal from the barn to the storage tank, and storage tank acidification during the summer period where higher methane emissions are expected. Results show that frequent flushing reduce methane emissions > 50 % in the barn, but depending on environmental conditions, some of the reduced emissions are instead emitted in the outside storage.
Publikationsdatomaj 2022
StatusUdgivet - maj 2022
BegivenhedZero Greenhouse Emission in High Productive Agriculture - Tuborg Havnevej 19, Hellerup, Danmark
Varighed: 3 maj 20225 maj 2022


KonferenceZero Greenhouse Emission in High Productive Agriculture
LokationTuborg Havnevej 19