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

PARALLEL SESSION 3C: SHEEP AND DAIRY PRODUCTION SYSTEMS 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
teric fermentation was calculated using a model by Kirchgessner (1995), while the IPCC model (2006) was
used for sensitivity analysis.
GHG emissions are calculated for the functional units ‘ha of cultivated area’ and ‘kg FPCM (fat- and protein-corrected)
milk produced’. For calculating the milk production-related impacts the emissions directly
associated with cash crops were excluded, while emissions for dairy production were allocated economically
between milk, meat and live animals output. Changes in productivity due to GHG mitigation measures have
to be determined exogenously. Each farm was assessed a) without implementation of the measures and b)
with each of the measures implemented individually. The difference in GHG emissions between both states
of a farm is interpreted as the effectiveness of the measure for mitigating GHG emissions on the specific
farm.
3. Results
3.1 GHG emission profiles without implementation of GHG mitigation measures
Without any mitigation measure implemented the dairy farm (DF) emits 139 t CO2-eq, while the mixed
farm (MF) 278 t CO2-eq annually (Fig. 2; columns). Per hectare, this means almost equal emissions of 5.54 t
CO2-eq (DF) and 5.50 t CO2-eq (MF), respectively. Both farms have a similar stocking density. However,
the MF has a higher production. Therefore, the MF is more GHG efficient (0.89 kg CO2-eq/kg milk) compared
to the DF (1.08 kg CO2-eq/kg milk) (Fig. 2; diamonds). The main reason for this difference lies in the
more favourable climatic conditions for the MF as it is located in the lowlands and benefits from a longer
vegetation period and higher temperatures.
The by far greatest share of GHG emissions is associated with enteric fermentation of both dairy cows
and offsprings (DF: 56.1%; MF: 55.7%) (Fig. 2). Further important factors are manure management with
18.6% (DF) and 20.7% (MF), respectively, and fodder production (DF: 18.7%; MF: 13.7%). While the DF
does not purchase any fodder from outside, the mixed farm imports concentrates (4.4%) which contribute
1.9% to the total emissions.
Figure 2. Annual GHG emissions (CO2-eq) on a typical Swiss organic dairy and mixed farm
3.2 Mitigation potential of the measures
Effective measures are conversion to full-grazing systems, use of dual-purpose cattle breeds, increased
number of lactations of dairy cows, composting livestock manure, use of photovoltaics, use of solar heat, and
optimisation of machine life. At the dairy and mixed farm, respectively, 5.4% and 5.5% of mitigation can be
realised by technical means (use of photovoltaics, optimisation of machine life, energy-efficient milk cooling
devices, application of eco drive mode, optimisation of machines and tractors, use of solar heat) and 15.4%
and 12.9% with agronomic measures (composting livestock manure, increased number of lactations of dairy
cows, use of dual-purpose cattle breeds, conversion to full-grazing system, shade trees on pastures, concentrate-free
feeding rations) where losses in productivity may occur. Total mitigation potential of the measures
analysed is 20.8% (dairy farm) and 18.4% less emissions (mixed farm), respectively.
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