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Life cycle assessment (LCA) of environmental impacts in organic broiler production chain - Fan Zhang

The aim of the present study was to apply the life cycle assessment (LCA) method, using Simapro software, to evaluate the environmental impacts of organic broiler production chain and find out the main impact contributors.

The aim of the present study was to apply the life cycle assessment (LCA) method, using Simapro software, to evaluate the environmental impacts of organic broiler production chain and find out the main impact contributors. The functional unit was one kg of organic fresh chicken fillet from cradle to slaughterhouse gate along the production chain. Inventory data from database Ecoinvent, literature and expert consultations were used in the LCA model. The result showed that feed production was the major contributor to most of the environmental impacts, accounts for 65.7% of global warming potential (GWP), 78.9% of eutrophication, 80.5% of land use and 57.8% of fossil energy use, except acidification with contribution of 41.1%. Broiler farm is the second largest contributor for most of the environmental impacts. It contributes 23.7% to GWP, 57.7% to acidification, 20.8% to eutrophication and 18.8% to fossil energy use. Producing one kg of fresh chicken fillet required 10.7 m2 of land and 25.8 MJ of cumulative energy. It resulted in the emission of 4.11 kg CO2 eq, 0.056 kg SO2 eq and 0.327 kg NO3 ‐ eq.

The overall environmental burdens in organic production chain were heavier than that found in conventional production chain (already available). Due to longer production cycle, more feed was needed for organic broilers (i.e. higher feed conversion ratio), which resulted in higher environmental burdens. Ingredients used in organic production chain were produced organically with lower yield. More land was needed during feed production phase with a higher emission. Large emission from manure on farm level resulted in high value in acidifying emissions, accompanied by eutrophication burdens coming from the nitrous oxide surplus. Feed production, as a determinant factor, is worth to be paid attention concerning the environment improvement. After comparison with different organic feed diets, using maize as main ingredient and partial replacement of whole extruded soybean with local peas was effective to improve the environmental burdens. Other improvements on broiler farm level and slaughterhouse level were also able to realize environmental improvement. Energy saving on broiler farm and using green energy reduced the fossil energy demand and GWP. Increase of carcass yield can decrease all the five environmental impacts. Further studies, concerning genetic improvement or ammonia emission reduction on broiler farm, could be done to reduce environmental burdens in organic broiler production chain.

Student: F Zhang

Supervisor: T Viets

24 Ects