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

GROUP 1, SESSION A: ANIMAL PRODUCTION SYSTEMS 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
710
38. System delimitation in life cycle assessment of aquaculture
Biniam Samuel-Fitwi 1,2,* , Jan P. Schroeder 2 , Carsten Schulz 1,2
1 Institute of Animal Breeding and Animal Husbandry, Christian-Albrechts-Universität zu Kiel, 24098 Kiel,
Germany, 2 Gesellschaft fuer Marine Aquakultur (GMA) mbH, Hafentoern 3, 25761 Buesum, Germany,
Corresponding author. E-mail: biniam@gma-buesum.de
In the past two decades, life cycle assessment (LCA) is recognised as a standardised and structured method
of evaluating the environmental impacts arising throughout the entire life cycle of a product, process or activity.
However, methodological issues still exist, when allocating the environmental burden of a specific
production system between products and co-products. According to the ISO standards, the first option is to
avoid allocation by making use of a subdivision or to expand the systems investigated. Aquaculture system
hardly applied system expansion whenever a multifunctional process has more than one functional flow. The
objective of this study is to model the system expansion for aquaculture production. The different affected
processes with co-products are selected for system expansion. Thus, in this study we have considered the
system expansion in two different stages in the life cycle of the fish production: aquacultural stage, with case
study of trout aquaculture; and feed manufacturing stage. Rainbow trout (Onchorhynchus mykiss) production
was used as a case study to illustrate the method using different scenarios of system expansion. This article
showed that system expansion best describes the environmental impact of systems affected by increase in
demand of rainbow trout.
Table 1. Relative emission load of rainbow trout farming estimated following different scenarios of system
expansion. The results are characterised results and are related to the functional unit: 1 kg of rainbow trout
demanded in Germany.
Impact cate-
Scenario Scenario Scenario Scenario Scenario Scenario
gory Unit I II III IV V VI
Acidification
kg SO2
equiv. 0.0077 0.0083 0.0113 0.0113 0.0090 0.0086
kg PO4
Eutrophication equiv. 0.0600 0.0601 0.0604 0.0601 0.0599 0.0598
Global warm- kg CO2
ing
Land competi-
equiv. 0.7670 0.9000 2.3219 3.6333 2.5516 2.4500
tion m²a 0.7422 0.7440 1.3030 1.0268 0.6013 0.5996
Figure. 1 Relative emission load of rainbow trout aquaculture using different system expansion scenarios.