Life cycle assessment - a tool for evaluating resource and environmental efficiency of agricultural products and systems from pasture to plate

Life cycle assessment is a useful tool to evaluate the resource use and environmental efficiency of agricultural systems and products, and to account for these along the whole supply chain or life cycle. Its application to agricultural products is most evident with carbon footprinting, where it is being used at industry, policy and consumer levels including for eco-labelling. Research in dairy, sheep and beef systems has shown that the farm-related stage is the main contributor to product carbon footprints and that in New Zealand they have been gradually reducing over time with increasing productivity. While the carbon footprints of New Zealand pastoral agricultural products are generally low compared to overseas products, there can be up to a two-fold variation between individual farms, illustrating the potential for on-farm efficiency gains. Fossil fuel and total energy use on New Zealand farms are low compared to overseas but are increasing with greater use of high energy-demanding nitrogen fertiliser. Water footprinting is likely to become an important resource indicator with the global focus on fresh-water scarcity. A key benefit of life cycle assessment is that it enables evaluation of the potential impacts of products on multiple resource use and environmental indicators for system optimisation.