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Life Cycle Assessment: Principles, Practice and Prospects
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a combination of caution and caveats are required so that the risks and uncertainties associ-
ated with poorly defined systems are adequately identified.
Variability between systems and farming conditions brings data transferability and meth-
odology/boundary selection challenges. Hence, as in the sugar cane study, it may be difficult to
draw ‘average’ conditions reliably and therefore make assumptions about system truncation.
Consider the case of tomato ketchup. Tomato production systems vary according to availabil-
ity of sunlight and growing temperatures. Also, while the production of the sauce is a more
controlled and predictable process, there is then a less predictable and less known use phase.
As highlighted in problems around Tesco’s efforts to develop carbon labels in the UK, a bottle
of ketchup that sits in a refrigerator for one year could be considered to contain 90% more
embodied energy than a bottle that is consumed within one month.
It would be erroneous to conclude from all these difficulties that agriculture does not lend
itself well to LCA. Although it is true that LCA was developed within the more controlled, pre-
dictable and readily measurable factory-industrial complex, and that farmland is infinitely
variable, as is weather and climate, seed types, rates and practices of application of fertilisers
and pesticides, proximity to and sensitivity of local hydrological systems and so on, LCA is the
appropriate means to compare life cycle environment implications of different agricultural
options. The answer is not to abandon LCA but to build more LCA capacity, to extend its use
and redouble the research effort in agriculture – and to learn how to do LCA smarter. This can
be achieved through further protocol and methods development and standardisation, to
maximise comparability of studies and compatibility of data. It can also be achieved through
the development of ‘quick LCA’ tools and calculators. These can be developed from better
understanding of the variability of farming systems, and allow users to input various parame-
ters to enable localised and specific evaluations to be achieved more quickly and easily than
through full LCA studies.

9.7.3 What issues fall ‘beyond’ LCA and how can the interface between LCA
and other design-decision support techniques be optimised?
Inevitably, there are challenges in the environmental assessment of agricultural practices for
which LCA is unlikely to be the appropriate vehicle in finding the solution. For example, LCA
is limited as a comparison tool in that it requires a similar unit of comparison to be achieved.
Hence, comparing apples from an orchard system in Victoria with apples from an alternative
system in New Zealand is within the bounds of LCA, provided we accept the assumption that
these are the only important functional outputs of the two systems. In reality, agriculture often
provides both economic and environmental/social services in addition to those associated
with the food produced, such as rural landscape amenity value, natural heritage, ecosystem
support and stewardship. Hence, it would be a mistake to advocate the adoption of LCA as the
only or primary tool, as there will always be a need for tools other than LCA in environmental
assessment of agricultural and related rural systems. Specifically, land management tools
provide a site-specific context for study, whereas LCA is an essentially systematic technique,
where assumptions need to be drawn across different situations to produce aggregated results.
Other challenges for LCA arise from dynamic economic factors that continually reshape
agricultural systems. Population growth and agricultural technologies affect relative supply
and demand and the debate over sustainable food supply is hundreds of years old and remains
controversial. Bartle (2007) describes how agricultural production has outstripped population
growth in many countries and the real price of food has dropped dramatically while food
intake has increased. Across the European Union and the United States of America (USA),
up to 20% of land has been set aside to avoid surplus agricultural production. However, the

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