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Understanding the environmental impacts
associated with our food production and
consumption is a prerequisite for identifying
pathways towards a sustainable future. The
agricultural sector plays a significant role in
a range of environmental impact categories.
While a relatively narrow range of produc-
tion technologies is used for most products
worldwide, agricultural production practices
are extremely diverse. Comparison of im-
pacts associated with consumption of similar
agricultural products produced at different
locations and/or under differing practice and
thus requires a thorough understanding of
the individual production practice. Results
from locations with different climatic and
topographic conditions, as well as countries
with dissimilar management history, tradi-
tions and political incentives for agricultural
systems, are not directly transferable from
case to case, and therefore specific data must
be collected.
The Industrial Ecology programme has in col-
laboration with the Norwegian Institute of
Agriculture and Environmental Research and
The Swedish Institute for Food and Biotech-
nology studied the environmental impacts
from selected food chains in Norway based
on grain, milk and meat production. Here the
results on the environmental impact, based
on an LCA approach, of producing grain
(barley, oat, spring wheat and winter wheat)
in Norway were presented. The assessment
covers processes from cradle to farm gate,
including all farm activities related to grain
cultivation, as well as the production and ac-
quisition of machinery, equipment and build-
ings, diesel and oil, fertilizer, lime, seeds and
pesticides.
In this study, significantly higher environ-
mental impacts were found than reported
in similar studies on grain production. This is
primarily caused by a more extensive system
included and clearly demonstrates the need
for setting the system boundaries so that im-
portant processes for environmental impact
caused by food production are not excluded.
In many studies manufacturing of machinery,
buildings, humus mineralization, production
and use of pesticides and/or NOX loss due to
use of mineral fertilizer are excluded, but in
this study it is shown that all of this have a
significant environmental impact.
The assessment gave a CC impact of 0.79,
0.77 and 0.74 kg CO2-eq for production of 1
kg barley, oat and spring wheat, respectively.
The choice of system boundaries was found
to have great impact on the results, and CC
impact was reduced by more than 40% when
factors that are not commonly reported in
literature were excluded. This clearly dem-
onstrates the need of comprehensive docu-
mentation of system boundaries in order to
performmeaningful comparisons of environ-
mental impact caused by grain production
under different conditions.
Moreover, the sensitivity analysis showed
that CC was very sensitive to changes in the
estimated NO-emission from fertilizer and
the rate of humus mineralization. Imple-
menting good methods for estimating these
emissions are thus crucial for robust LCA as-
sessments.
A large share of impact on toxicity categories
originates from construction of machinery.
For a detoxification of the production system
as a whole without focusing on potential
local conditions, better maintenance of ma-
chinery could thus be as important as chang-
es in spraying regime. This is not shown in
previous studies on grain production due to
their more restricted system boundaries.
The importance of a carefully selection of
functional unit is demonstrated. kg dry mat-
ter is often used, but this is not always a good
measure on the quality of the food produced;
energy and protein content can be of more
interest. In this study this does not change
the overall rating of the included species, but
the relative differences changes.
Contact person:
Professor Anders Hammer Strømman
anders.hammer.stromman@ntnu.no
Figure: Environmental impacts from produc-
tion of 1 kg barley, oat and spring wheat,
separated in different stages in the produc-
tion. Each subfigure shows the environmen-
tal impact on one impact category based on
Environmental impact and resource use efficiency of selected food pro-
duction chains in Norway – a life cycle assessment (LCA) approach
RESEARCH