LCA Food 2012 in Saint Malo, France! - Manifestations et colloques ...

PARALLEL SESSION 4C: CROP PRODUCTION SYSTEMS 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
manufacturing and energy use also contribute in a significant way to greenhouse gases emissions and, logically,
to energy consumption.
The impact on water depletion depends on the quantity of water used for crop irrigation, but also on the
phosphorous fertiliser production and, to a smaller extent, on storage.
Fertiliser production is the main stage impacting freshwater eutrophication, along with their application
on the fields. Field emissions are mostly due to soil erosion that carry away P2O5 particles and are slightly
linked with P-fertiliser application.
Aquatic ecotoxicity is largely impacted by the ecotoxicity profile of the plant protection products applied
on the field.
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3.2. Scattering of the impact indicators (GES & acidification)
Results concerning the scattering of the impact indicators are based on intra-cooperative data in order to
free oneself from variability between wide regional pedoclimatic conditions. Results submitted here are
those of one cooperative among the 6 involved in the study. This cooperative chose to subdivide its territory
into 4 scenarios depending on soil type.
Figure 6. Inter-field variability regarding the climate change and acidification indicators
GHG emissions rank from 0,36 to 0,39 kg eq.CO2 / kg wheat grain, depending on the scenario. Statistical
Student test (Table 2) shows that there is a significant difference between the 4 scenarios.
Potential acidification impact ranks from 5.4.10 -3 à 6.5.10 -3 kg eq.SO2 / kg wheat grain, depending on the
scenario. Statistical analysis (Table 2) shows that there is a significant difference between the 4 scenarios.
Beyond these observations on differences between scenarios, it is important to note that inter-field variability
is substantial. It is much higher than variability between soil types. This is why in a given improvement
strategy, it will be more efficient to work on the reduction of the impacts of the fields with the higher
impact taken as a whole than to select wheat produced on the lower impacting soil.
Table 2. Statistical comparison of the climate change and acidification indicators results of the 4 wheat production
scenarios
Two-by-two comparison with a statistical Student test
P-value
Climate change Acidification
Scenarios 3 vs. 1 6.04E-67 1.36E-38
Scenarios 3 vs. 2 3.83E-64 1.09E-35
Scenarios 3 vs. 4 3.74E-72 1.20E-13
Scenarios 4 vs. 1 1.48E-2 1.92E-06
Scenarios 4 vs. 2 3.43E-2 5.46E-3
Scenarios 2 vs. 1 7.84E-1 7.59E-3
3.3. Effect of winter wheat technological quality on environmental impacts
Results regarding the scattering of the impact indicators between high-protein wheat and winter wheat are
also based on intra-cooperative data. The following results are those of one cooperative that chose to study
its wheat’s impacts depending on winter wheat technological quality.