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

PARALLEL SESSION 4A: CARBON FOOTPRINT 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
Table 4. Carbon footprint of asparagus cultivated in an integrated production system
Integrated Production (IP) of Asparagus
Farm carbon footprint per area [t/ha]
Average asparagus yield per ha and per year (over 11 years) 7.020 t/ha
Yearly cultivation, tillage and planting (per ha) without biogenic carbon 2.406 t CO2eq/ha/a
LUC (asparagus after annual cropland) 0.0 kg CO2eq/ha/a*
Bio-genic carbon per ha (6% dry matter of asparagus) -0.198 t CO2eq/ha/a
From planting to harvest (over 11 years) (ha) 2.208 t CO2eq/ha/a
360
Farm carbon footprint [g per kg]
From planting to harvest (over 11 years) (kg) 315 g CO2eq/kg asparagus
Cooling, grading and packaging (5 kg cardboard carton) 086 g CO2eq/kg asparagus
Carbon footprint from seedling to harvest according to PAS 2050 -1 (B 2 B) 401 g CO2eq/kg asparagus
Product carbon footprint [g per kg]
Overall transportation farm to retail 096 g CO2eq/kg asparagus
Use phase (shopping tour, fridge and cooking) 304 g CO2eq/kg asparagus
Product Carbon Footprint from harvest via use phase to disposal 400 g CO2eq/kg asparagus
Product Carbon Footprint (PCF) CO2eq/kg asparagus (B 2 C) 801 g CO2eq/kg asparagus
*LUC result was negative but assumed as zero.
4. Discussion- Carbon reduction potential
The pilot project PAS2050-1 sponsored by Productshap Tuinbow was successful and established guidelines,
with examples and references for the horticultural sector, and appears the first product category rule
(PCR). Carbon reduction potential for autumn pumpkin, chosen as part of the associated pilot project, appears
in three sectors i) potassium fertilisation, ii) reduction of nitrous oxide (N2O) emissions and iii) consumer
behaviour. The first carbon reduction potential lies in improving viz., increasing the potassium fertilisation
in all farming systems, except for the large farm, which would increase yields and hence reduce the
product carbon footprint (PCF). The second carbon reduction potential lies in the reduction of N2O emissions:
With 99%, nitrous oxides had the largest share of the carbon footprint during cultivation. Use of the
global IPCC values of 1.0% (IPCC, 2006) or 1.25% (IPCC, 2007) N2O-N per kg applied fertiliser-N would
nearly double the N2O from 0.8% during cultivation (Kuikman et al., 2006). By contrast, the use of nitrification
inhibitors such as DMPP with a 49% reduction in nitrous oxide emissions from regional soils (Weiske et
al., 2001) could halve the carbon footprint during cultivation. Alternatively, depot nitrogen fertilisers like the
ammonium-based CULTAN system (Bacher and Blanke, 1996; Sommer and Scherer, 2009) could reduce the
amount of applied nitrogen by ca. 25%.
The third carbon reduction potential is the consumer behaviour regarding the means of transport for shopping.
The use of bicycles, public transport or non-fossil-based cars could reduce the product carbon footprint.
5. Conclusion
Overall, the application trial showed PAS 2050-1:2012 is suitable for the horticultural industry. These
supplementary requirements enable the user in the horticultural business to have a clear and structured approach
for the special issues in this specific sector. The new supplementary requirements, which offset biogenic
carbon in the horticultural/harvested product (Table 2), result in lesser carbon footprint values than in
previous studies. In the present pilot study, the product carbon footprint (PCF, cradle to grave, or B 2 C) was
3% (asparagus), 8% (rhubarb) and 17% (strawberry) less due to subtracting the biogenic carbon in the harvested
produce. Hence, larger yields and produce with a large carbon contents play an increasing (positive)
role in the carbon footprint; yields e.g. in pumpkin cultivated in the same region (soil and climate) with a
different cultivation system (organic or IP) can vary by a factor of 3 (Table 3).
Our value of 0.801 kg CO2eq/kg asparagus compares with another study on carbon emissions in the horticultural
sector and 0.7-0.8 kg CO2eq/kg asparagus in Switzerland (Stoessel et al., 2012), in which nitrogen
fertiliser including related N2O emission played the greatest role. The Swiss values may be 10-15% less,
because the system boundary of the study ended at retail level. This section from retail to the consumer was
0.304 kg CO2eq/kg asparagus in the present pilot study (Table 4), the PCF to retail amounted to 0.497 kg
CO2eq/kg asparagus in Germany.
6. References
Bacher, W., Blanke, M.M, Pring, R. Baker, E.A., 1996: Ammonium nutrition enhances chlorophyll and glaucousness in Brassica
kohlrabi. Annals of Botany 78, 559-604.