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

PARALLEL SESSION 6B: FISHIERIES, SOIL, AND EMERGY METHODS 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
3. Results
3.1 Characterisation factors
Fig. 1 shows the regionalised CFs for (a) the resource-depletion impact pathway and (b) the ecosystemquality
impact pathway. As stated previously, for resource depletion, larger CFs were for thinner soils, and
for ecosystem quality, larger CFs were for soils with higher biomass productivities.
a
Resource depletion [MJse g -1 b
6 soil loss] 24 0 Ecosystem quality [decimal % NPP lost] 1
Figure 1. Characterisation factors for (a) resource depletion and (b) ecosystem quality.
3.2 Case study on food and energy crops
At the LCI level, soil erosion of three of the crops grown in the evaluated rotations as well as of the unseeded
fallow reference system are depicted in Fig. 2. Results are shown grouping the analysed plots on the
ten main water-basins in Spain and on the country scale. It can be seen how soil loss varies as a function of
location for the same crop, hence the importance of including geospatial information as accurately as possible
in the inventory step.
Figure 2. Soil erosion (t ha -1 y -1 ) on the 120 studied plots grouped on the water-basin and arithmetic average
±standard deviation on the country level. The reported soil losses were calculated for a whole year (crop +
crop residues + rough fallow before next seeding).
Results at the LCIA stage for the five crop rotations evaluated are shown in table 1. As in the inventory,
damage to resources and to ecosystem quality varies greatly between water-basins for one and the same crop
rotation, with a coefficient of variation higher than 60% in almost all cases (except for the poplar rotation,
CV is 35%). According to the presented results, the most appropriate combination of rotation and location
was the poplar energy-crop short rotation forestry grown in the North of the country (Duero water basin in
table 1). Other water basins, such as the Guadiana (Central Spain, results not shown here) scored very close
to the Duero water basin.
525