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any bulk transport by air, will invariably multiply the proportion of energy demand attributable
to transport.
Recognising that food miles is an inadequate proxy for environmental burden identification
does not mean that the alleged benefits of local, organic, or home grown food should be rejected.
Indeed, a UK study for the Department for Environment, Food and Rural Affairs (DEFRA:
AEA 2005) includes a case study on imported organic wheat, which suggests that there are a
wide range of benefits associated with organic production systems, including reduced green-
house gas emissions, higher soil quality and biodiversity, and lower waste and pollution includ-
ing eutrophication. The calculations presented indicate that energy savings in production of
organic winter wheat may be equivalent to almost 800 kilometres of road transport. Logically,
local, organic production may provide further benefits, provided these systems do not involve
increased impacts elsewhere in the system. Anderson-Wilk (2007) quotes a report from the Iowa
State University Leopold Centre for Sustainable Agriculture regarding ‘community-supported
agriculture’ (CSA), which is based on local, communal gardening: ‘CSA may minimize some of
the negative effects of more conventional systems of food production and distribution because
it involves less chemical use, less soil erosion, less food packaging, fewer food miles and more
crop and ecosystem diversity’ (Tegtmeier and Duffy 2005). There are many such statements in
the literature, although the evidence in the form of systematic and complete LCA data and
analysis is less widespread, and there is an urgent need for more studies indicating the full
system benefits (and costs) of organic and localised production systems.

9.7 Discussion: LCA and farming in an environmentally
constrained world
As our main food source, agriculture is a major, essential activity, and one which is conten-
tious as a major user of land and water and emitter of greenhouse gases. This contention will
increase as the remaining stock of ‘natural’ land is used, population and food consumption
continues to rise, and scrutiny of sources of greenhouse gas emissions increases. Regarding the
latter, agriculture is seen as both a major ‘problem’ (emitter) and potential ‘saviour’ – a source
of fossil fuel substitutes and carbon sinks. The choices made about future technologies and
practices will determine environmental outcomes, and LCA can play a key role in identifying
preferable courses of action. Yet there are challenges to be overcome both in LCA practice and
in realising sustainable agriculture options. Three key questions are posed here.

9.7.1 Can the ‘new’ agriculture be sustainable?
The industrial economy of the last 100 years has been based on historical biomass deposits in
the form of crude oil, natural gas and coal. It is not surprising then that, as these historical
reserves become limited in supply, society will look to more immediate biomass production
systems to fill the gap (i.e. agriculture and forestry). Hence, the prospect of a ‘new’ agriculture
industry is raised in which biomaterials, biofuels and other bio-energy sources will be increas-
ingly produced, harvested and exploited in place of current fossil fuel-dependent technologies.
Life cycle thinking, of course, cautions against the immediate conclusion that such technolo-
gies will be ‘carbon neutral’, particularly when we start to construct life cycle process chains of
likely comparative systems. Fossil-based polymers or fuels have short production cycles based
around winning crude oil and processing this into the final product, whereas agricultural
alternatives often involve a long range of activities from seed manufacture to fertilisers, pesti-
cides, tillages and harvesting, and onto processing and production.
A full discussion of the life cycle implications of the myriad of new bio-based technologies
is outside the scope of this book, although discussion of biofuels is included in Chapter 10, and

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