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
In a sensitivity analysis the time perspective was tested and characterisation factors (CF) generated up to 500
projection years. With longer time span (T) used for projections, the higher were badly managed stocks are
relatively contributing in WPY and the higher the average WPY became for all stocks. Most stocks stabilise
asymptotically with T approaching large values. Exceptions are heavily exploited stocks which instead increase
rapidly but asymptotically approached a constant increase rate. However with a longer projections
(typically >100years) it is unrealistic that a constant fishing mortality could be sustained, unlikely that the
reference values would still be updated, and cause large error propagations. With a too short T, restoration of
overexploited stocks will not be the optimal scenario and instead favoured by the (unwanted) scenario of
“killing all fish one year, leaving none to the next”. This forces a subjectively chosen T within the projection
range where CFs has not stabilised, which indirectly becomes a matter of weighing the importance of heavily
exploited stocks risk of depletion. For good and bad, the time dependency actually mimics the dilemma of
fishery management; balancing the uncertainty of future catches against short time yields which may jeopardize
the long term revenue. One solution could be to formulate Hierachist, Individualist and Egalitarian
view perspectives by a convenient set of projections.
Decreased model- and input data uncertainty can be achieved by using the sub impact categories of Foverfishing
and B-overfishedness. F/FMSY based F-Overfishing is however the best choice based on input
parameter uncertainty since the BMSY assessment comes with a broader confidence interval in the original
assessments, and the temporal variation is smallest for F. Furthermore, sustainability of fishery or biotic resource
depletion potential will independent of measurement method always have high temporal variation due
to the fluctuating nature of the stocks, random environmental factors and political decisions influencing the
exploitation rates. Spatial variation is also substantial within each species group. For database purpose the
stock entries could be aggregated into optimally sized groups that minimize the representation bias, a practical
reason for this is that insufficient traceability legislations often renders it impossible to known the origin
of a fish product down to the relevant stock level. However, the undisputable best resolution would be
achieved if the LCA practitioner collected stock summary data in the same way as other inventory data (F,
SSB and limit values) for the actual stock of concern.
By this methodology, overfishing can be described as midpoint categories, but relating to damage of natural
biotic resources lays closest in term of future endpoint assessments, since Wasted Potential Catch is a mass
unit that could be translated into economical terms and compared with abiotic resource depletion. Natural
ecosystem damage could be compared in terms of pristine state for similar stocks, since a Schaeffer model
also indicates the carrying capacity (the unfished population) as 2Bmsy corresponding to natural ecosystem.
However relative importance in the ecosystem should then also be included for inclusion of both marine and
terrestrial fauna.
6. Conclusion
With the inclusion of biological impact categories, LCA´s are concluded to be a useful complementary tool
for fisheries managers, seafood industry or seafood labelling/consumer guides where quantitative overfishing
indices has been the missing part of the toolbox. We suggest Wasted Potential Yield and/or F-Overfishing B-
Overfishedness as impact categories depending on the scope of the study, and conclude them to meet demands
of applicability, relevancy and scientific soundness. Without directly addressing and quantifying the
biological effects of target stock, internationally acknowledged broadly as overfishing, any future seafood
LCA could be misinterpreted or even deliberately misused as a biased proxy for total “environmental” damage.
7. References
Anticamara, J.A., Watson R., Gelchu A., Pauly D. 2011. Global fishing effort (1950–2010): Trends, gaps, and implications. Fisheries
Research 107 (1–3):131-136.
EC 2003. COM(2003) 302 Integrated Product Policy - Building on Environmental Life-Cycle Thinking. Comisssion of the European
Communities, Brussels.
EC 2006. Implementing sustainability in EU fisheries through maximum sustainable yield Communication from the Commission to
the Council and the European Parliament. Brussels.
FAO 2008. The sunken billions the economic justification for fisheries reform. World Bank and Food and Agriculture Organization,
Washington DC.
FAO 2012. The state of world fisheries and aquaculture (SOFIA). Rome.
Finnveden, G., Hauschild M.Z., Ekvall T., Guinée J., Heijungs R., Hellweg S., Koehler A., Pennington D., Suh S. 2009. Recent
developments in Life Cycle Assessment. Journal of Environmental Management 91 (1):1-21.
Frank, K.T., Petrie B., Choi J.S., Leggett W.C. 2005. Trophic Cascades in a Formerly Cod-Dominated Ecosystem. Science 308
(5728):1621-1623.
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