POPULAR thinking about how to improve food systems often misses the point, according to results of a three-year global study of salmon production systems from Dalhousie University, Ecotrust and the Swedish Institute for Food & Biotechnology.
Rather than pushing for organic or land-based production or worrying about simple metrics such as "food miles," the study found that the world could achieve greater environmental benefits by focusing on improvements to key aspects of production and distribution.
For example, what farmed salmon are fed, how wild salmon are caught and the choice to buy frozen over fresh product matters more than organic versus conventional or wild versus farmed when considering environmental effects on a global scale such as climate change, ozone depletion, loss of critical habitat and ocean acidification, the study found.
The study is one of the first to take a comprehensive, global-scale look at a major food commodity from a full lifecycle perspective, and the researchers examined everything: how salmon are caught in the wild, what they're fed when farmed, how they're transported, how they're consumed and how all of this contributes to both environmental degradation and socioeconomic benefits.
The researchers behind the study sought to understand how the world could develop truly sustainable food systems through the lens of understanding the complexities associated with wild and farmed salmon production, processing and distribution.
They found that decision-making for food must fully account for the lifecycle socioeconomic and environmental costs of food production.
The principal researchers for the study included Dr. Astrid Scholz, vice president of knowledge systems at Ecotrust in Portland, USA; Dr. Ulf Sonesson, a researcher at the Swedish Institute for Food & Biotechnology in Gothenburg, Sweden; and Dr. Peter Tyedmers, associate professor at Dalhousie University in Halifax, Canada.
How to measure the importance of such effects is ultimately subjective and in the realm of policy and culture, but using a comprehensive approach provides a more nuanced process for informed decision-making, the report said.
The researchers chose salmon as their focus as the fish exemplified important characteristics of modern food systems yet offered unique opportunities for comparison.
It is available around the world at any time and in any location regardless of season or local ecosystem, it is available in numerous product forms and it is distributed using a variety of transport modes.
However, unlike many other food systems, salmon are available from both wild sources and a range of farmed production systems.
The researchers said early results of the study found that growing salmon in land-based farms could increase total greenhouse gas emissions tenfold over conventional farming depending on how and where the farming was conducted.
Beyond the farm, it's important to also consider the total effect of food preparation. Driving to the store alone and then cooking alone at home has a big environmental footprint.
Going out to dinner more, or just eating more frequently with friends and family at home, is more beneficial, the researchers said.
For concerned consumers, it's important to think about how food was produced and transported - not just where it was produced - when making food choices.
Initial findings from the study (more are due with the final report in 2010) show that:
- Air-freighting salmon, or any food, results in substantial increases in environmental impacts. If more frozen food were consumed, more container ships would be used to ship food. Container ships are the most efficient and carbon-friendly way to transport food. (In Japan, which gets much of its fish by air, switching to 75pc frozen salmon would have more benefit than all of Europe eating locally farmed salmon.)
- A full lifecycle assessment approach to research provides a more nuanced process for informed decision-making. Even food has a lifecycle, and trade-offs may be inevitable.
- Contrary to what is widely perceived, the vast majority of broad-scale resource use and environmental impacts (energy inputs, greenhouse gas emissions, etc.) from conventional salmon farming result from the feeds used to produce them. What happens at or around a farm site may be important for local ecological reasons but contributes very little to global-scale concerns such as climate change.
Across the globe, what is used to feed salmon and the amount of feeds used vary widely. As a result, effects are very different. Norwegian salmon farming resulted in generally lower overall effects, while farmed salmon production in the U.K. resulted in the greatest effects.Growing organic salmon using fish meals and oils from resource-intensive fisheries results in effects very similar to conventional farmed salmon production.If not planned carefully, technological fixes aimed at addressing local environmental challenges associated with conventional salmon farming can result in substantial increases in global-scale environmental impacts.* More information on this study and related publications are available at www.ecotrust.org/l ca.
* The most recent published paper from the study can be found in the Environmental Science & Technology journal here.
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