Published in

CSIRO Publishing, Animal Production Science, 9(56), p. 1432, 2016

DOI: 10.1071/an16009

Links

Tools

Export citation

Search in Google Scholar

Greenhouse-gas emissions from stockpiled and composted dairy-manure residues and consideration of associated emission factors

Journal article published in 2016 by J. Biala, N. Lovrick, D. Rowlings, P. Grace ORCID
This paper was not found in any repository, but could be made available legally by the author.
This paper was not found in any repository, but could be made available legally by the author.

Full text: Unavailable

Green circle
Preprint: archiving allowed
Green circle
Postprint: archiving allowed
Red circle
Published version: archiving forbidden
Data provided by SHERPA/RoMEO

Abstract

Emissions from stockpiled pond sludge and yard scrapings were compared with composted dairy-manure residues blended with shredded vegetation residues and chicken litter over a 5-month period at a farm in Victoria (Australia). Results showed that methane emissions occurred primarily during the first 30–60 days of stockpiling and composting, with daily emission rates being highest for stockpiled pond sludge. Cumulated methane (CH4) emissions per tonne wet feedstock were highest for stockpiling of pond sludge (969 g CH4/t), followed by composting (682 g CH4/t) and stockpiling of yard scrapings (120 g CH4/t). Sizeable nitrous oxide (N2O) fluxes were observed only when temperatures inside the compost windrow fell below ~45−50°C. Cumulated N2O emissions were highest for composting (159 g N2O/t), followed by stockpiling of pond sludge (103 g N2O/t) and yard scrapings (45 g N2O/t). Adding chicken litter and lime to dairy-manure residues resulted in a very low carbon-to-nitrogen ratio (13 : 1) of the composting mix, and would have brought about significant N2O losses during composting. These field observations suggested that decisions at composting operations, as in many other businesses, are driven more by practical and economic considerations rather than efforts to minimise greenhouse-gas emissions. Total greenhouse-gas emissions (CH4 + N2O), expressed as CO2-e per tonne wet feedstock, were highest for composting (64.4 kg), followed by those for stockpiling of pond sludge (54.5 kg) and yard scraping (16.3 kg). This meant that emissions for composting and stockpiling of pond sludge exceeded the new Australian default emission factors for ‘waste composting’ (49 kg). This paper proposes to express greenhouse-gas emissions from secondary manure-management systems (e.g. composting) also as emissions per tonne wet feedstock, so as to align them with the approach taken for ‘waste composting’ and to facilitate the development of emission-reduction methodologies for improved manure management at the farm level.