Trends in environmental impacts from the pork industry: final report

Trends in environmental impacts from the pork industry: final report

Over the past four decades, major changes have occurred in Australia’s pork industry, affecting productivity and the environmental impacts from production. Using a life cycle assessment (LCA) approach with a ‘cradle-to-farm gate’ boundary, the changes in greenhouse gas (GHG) emission intensity and key resource use efficiency indicators (fresh water consumption, water stress, fossil fuel energy demand and land occupation) were determined at decade intervals between 1980 and 2010. Results for 2020 were projected from trends identified in the 1980 to 2017 data. Impacts were reported per kilogram of pork (live weight – LW) produced in each decade.

The analysis showed that over the four decades since 1980 there has been a decrease in GHG emission intensity, excluding land use (LU) and direct land use change (dLUC) emissions, of 69% from 10.6 to 3.3 kg CO2-e kg liveweight (LW)-1. GHG emissions associated with LU and dLUC were estimated to have declined by 89% since 1980. Fresh water consumption decreased from 441 L kg LW-1 in 1980 to a projected 90 L kg LW-1 in 2020. Water stress followed a similar trend, decreasing from 287 L H2O-e LW-1 in 1980 to a projected 57 L H2O-e LW-1 in 2020. Fossil energy use decreased from 34 MJ kg LW-1 in 1980 to a projected 14 MJ kg LW-1 in 2020. Land occupation decreased by 63% from 31 m2 kg LW-1 in 1980 to a projected 11 m2 kg LW-1 in 2020.

Improvements were principally driven by improved herd productivity, changes in housing and manure management, and improved feed production systems. In the pig production system, improved herd and system efficiency led to improved feed conversion ratio, resulting in lower feed requirements, and reduced manure production. This was partly also associated with reduced feed wastage, which had a disproportionally larger effect on reducing manure GHG emissions.

Concurrently, improvements in feed grain production systems resulted in lower impacts per tonne of feed grain produced. This was related to reduced tillage, higher yields and a decrease in the proportion of irrigation water used for grain production. This paper discusses the prospects and challenges for further reductions in greenhouse gas intensity and gains in resource use efficiency for Australian pork production. This study has shown that ongoing changes and improvements in production efficiency have resulted in large gains in environmental performance in the Australian pork industry.

APL Project 2017/2212.