Life Cycle Assessment (LCA) is a standardized method to assess potential impacts associated with a product by quantifying and evaluating the resources consumed and emissions to the environment at all stages of its life cycle. The development and application of the LCA methodology to agriculture and fisheries is a relatively recent approach.
Assessing the environmental burdens associated with aquafeeds is a critical component for evaluating and improving the environmental performance of aquaculture. Going beyond environmental impacts just at the farm level, studies undertaken under Aquamax aim to assess the environmental impacts associated with feeds and their utilisation for the different species at a much wider level. The stages assessed are: the extraction of the raw materials, the production and transformation of the primary ingredients used, the manufacturing of the feeds, the use of the feeds at the farm, transport at all stages, and the production and use of energy resources using different impact categories: energy use, net primary production use, eutrophication potential, global warming potential or acidifcation potential.
Under Aquamax the LCA methodology was not only applied to feedstuffs and feeds and their use but also to all stages of fish production under diverse farming systems (cages, raceways, ponds) prevailing in Europe or in Asia. The holistic nature of the LCA method enables evaluation of multiple impacts throughout the different stages of fish farming. This allows direct comparisons and assessment of the magnitude and importance of the different impacts. Development of LCA production process sheets and scenarios, once finished, will be used for the application of Aquamax results to modelling sector-wide uptake in the socio-economic analysis.
Life Cycle AnalysisEnvironmental impact assessment: ingredients, feeds and farm by Joël AUBIN, Joachim BOISSY, Abdeljalil DRISSI- INRA
One of the objectives of AquaMax is to propose sustainable fish feeds by replacing fish oil and meal by vegetable sources of lipids and proteins. To assess the fulfilment of this objective, an environmental assessment using Life Cycle Assessment (LCA) methodology is being conducted on the ingredients used in fish feeds, on the feeds themselves, and on the fish production at the fish farm. LCA is a technique for assessing the environmental aspects and potential impacts throughout the life of a product or service, from raw material extraction through to production, use and disposal.
Around 50 different feed ingredients have been described using LCA, based on a precise inventory of physical inputs and pollutants associated with their production and transformation. These inventories concern all ingredients used, both of terrestrial and of marine origin coming from different parts of the world. Using these data and the description of the feed production process, we have been able to conduct an environmental assessment of the different diets used. The LCA method has been applied to compare two trout diets, containing the same quantity of protein and energy, but differing in their fish meal content: 24% in the standard diet, 5% in the AquaMax diet. As expected, the Net Primary Production Use (kg C) reflecting the pressure on biotic resources decreases dramatically in the AquaMax diet (-73.5%). The energy demand (MJ) and the global warming potential (kg CO2-eq) remain equal between the diets, despite their different ingredient profiles. An increased level of inclusion of plant byproducts leads to increases in: land competition (m2), by 67%; water requirements, by 64% (due to the processing of high protein extracts -wheat and corn glutens); eutrophication potential (kg PO4-eq), by 53%; and terrestrial ecotoxicity (kg 1.4 DB – eq), by 50% (due to intensive agriculture products such as rapeseed oil). As a next step, animal production data (growth, survival rate, feed conversion ratio) were gathered from a commercial farm of one of the SME partner (Viviers de France) during a production of large trout (3kg) receiving these two feeds. These data were used to calculate the farm-level environmental impact of the production of one ton of fish, taking into account the feeds and the other production factors (farm energy use, liquid oxygen, fingerling production, equipment and infrastructure). Compared to the standard diet, the use of the AquaMax diet for the production of one ton of trout induces a reduction of the Net Primary Production Use by 64.5%. The energy demand and the global warming potential remain equal. The difference in land competition is still high (60%) as feed production is the major contributor to this impact category. For eutrophication potential and terrestrial ecotoxicity, the difference between the two diets is a lot less (12% and 18% respectively). This can be explained by the influence of other production factors, such as nitrogen and phosphorus emission at the farm outlet, which are more important than the feed effects. Since the river water entering the farm has been taken into account in the calculation, the water demand is no longer influenced by the feed. These two water uses need to be separated in further studies.
Conclusion: trout feed environmental assessment shows that, even if we can expect a good saving effect in terms of Net Primary Production Use (and no effect in terms of energy requirement and greenhouse gas emissions), the replacement of fish meal by vegetable sources can induce an increase in land competition as well as impacts such as eutrophication and terrestrial ecotoxicity. This has to be taken into account in the feed formulation in order to minimise these environmental effects, as well as water consumption.
Figure: Comparing 1 kg Soy meal with 1 kg Fish meal; method CML 1992 V2.03/W-European territory/normalization. Categories of assessed damages are global warming, ozone layer depletion, eco-toxicological, human-toxicological pollutants, eutrophication, acidification, smog and depletion of minerals and fossil fuels.
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Fish feed 
