What are the social costs and benefits of lignite application to reduce ammonia emissions in intensive feedlot?

Recent studies demonstrated that lignite application in feedlot can mitigate ammonia (NH3) emission from intensive livestock production, which is an important source of environmental pollution. However, the use of lignite on feedlot requires mining and transport of lignite, which are themselves sources of greenhouse gas and other gaseous pollutants. There is a need for an integrated assessment on the gas emissions to determine the potential impact of those additions to the production chain. Using a case study in Victoria, Australia, carbon dioxide (CO2) and NH3 were identified as key emission changes compared to business as usual (BAU). Social costs and benefits analysis indicated that these changes in emissions translate to social benefits of AUD$11 - $151 and $18 - $256 per cattle per year at lignite application rate of 3 and 6 kg m-2 respectively, while the corresponding social costs of the additional gaseous emissions are AUD$2 - $19 and $3 - $28 per cattle per year per 200 km. Our results indicate that the use of lignite in feedlot to mitigate NH3 can be targeted at feedlots located in proximity to lignite source, population centre and/or vulnerable ecosystems to maximise social benefits and minimise social costs. More broadly, estimating the social costs and benefits of changing manure management practice to mitigate NH3 emission generates information that can be used to evaluate alternative policies for N management.