Synopsis
Stewart Ledgard, AgResearch, spoke next on Life Cycle Analysis (LCA) and considering the total resource use or environmental emissions of a product from ‘cradle to grave’. This is being used in NZ to ensure that our producers can be competitive on the global stage in the light of food miles and carbon footprint labelling. This is now extending to other environmental impacts. EU Product Environmental Footprinting (PEF) is aiming to get consistency for consumers and may be a requirement for supply into the EU at some point in the future. Stewart showed international comparisons for NZ producers. Based on the average NZ farm, NZ milk production has the same, or a slightly lower, environmental footprint than European milk. Farms aren’t all average though. Studies comparing lamb production have shown NZ to have a lower footprint that the UK, even with the shipping component, and France. The animals are housed for at least some of the year in France. Shipping produce from NZ to the UK has been shown to have a smaller environmental impact than the consumer-related travel in the UK. Most of the GHGs related to lamb production are generated on farm. If animals are finished on grain there are lower GHG emissions per kg of meat, but more fossil fuels are used. The international LEAP programme is looking for consensus on developing LCA methods to ensure that product comparisons are robust. The EU PEF covers fifteen environmental impacts. Stewart concluded by stating that the NZ has amongst the lowest environmental footprint for dairy and sheep production in the world. Traditional NZ beef production is also towards the lower end of the global range. Looking forward there needs to be a global harmonization of LCA methodology.
Download slides
 2017NZAgGHGMitigationConference_Ledgard.pdf (1.43MB)
About Stewart
Stewart Ledgard is a Principal Scientist with AgResearch (a New Zealand Crown Research Institute) and is an adjunct Professor in Life Cycle Management at Massey University, New Zealand (NZ). He has worked with agricultural sector and policy groups in the areas of life cycle management and greenhouse gases for over 10 years, and in nutrient management for over 30 years.
Stewart has worked with government and agricultural sector groups in determining and reducing the carbon footprint of agricultural products, and has linked research in use of Life Cycle Assessment (LCA) in agricultural systems in a range of countries internationally. NZ research in this area involved development of methodology for carbon footprinting of dairy, beef, lamb, wool and venison. This methodology was then applied across regional and national farm datasets and used to determine the effectiveness of potential reduction options. International research has included training of researchers and linked research in Australia, Chile, Uruguay, France and the United Kingdom. Stewart is a member of the operations group (representing AgResearch) in the NZ Life Cycle Management Centre, which included co-supervision of a PhD student.
Stewart led a Technical Advisory Group (TAG) of the Livestock Environmental Assessment and Performance (LEAP) partnership associated with the Food and Agriculture Organization (FAO) on developing Guidelines for estimating greenhouse gas emissions from small ruminant supply chains. He is currently co-chairing another LEAP TAG on nutrient accounting and environmental assessment across multiple livestock supply chains.
Stewart has also worked on nutrient management research, covering work on initial development of the OVERSEER® nutrient budget model, nitrogen mitigation on farms, and on developing and evaluating practical nitrogen mitigation options for farmers. He has also worked with NZ policy groups, including several Regional Councils on approaches for landholders to work within limits on nutrient losses from catchments to meet water quality targets.  
Stewart has been active in publishing his research. This includes 8 book chapters, 116 scientific journal papers, 108 refereed scientific conference papers and over 350 other general publications and client reports.