Conference Paper

Soil, climate and cropping system effects on N 2 O accounting in the LCA of faba bean and cereals

DOI: 10.13140/2.1.4912.6401 Conference: LCA food 2012

ABSTRACT Greenhouse gas (GHG) emissions from soils cause uncertainties within Agricultural LCA. N 2 O affects global warming and is esti-mated with IPCC guidelines, agroecosystem models or direct measurements. CERES-EGC model was used to estimate N 2 O emis-sions from faba bean and winter cereals grown in two trials (ICC and CIMAS) with different climates. Model outputs were compared with IPCC estimates. Simulated N 2 O emission patterns showed emissions can be independent from fertiliser application dates or rates. This was due to soil moisture, rainfall and farming practices. Results showed the IPCC procedure estimated higher annual cere-als emissions of 740 g N 2 O-N ha -1 y -1 than simulation results and a lower estimation of 304 g N 2 O-N ha -1 y -1 for faba bean. Results revealed inclusion of climate, soil properties and management resulted in major variations of N 2 O emissions which CERES-EGC was able to capture. Thus, model estimates may increase accuracy of soil GHG emission in Agricultural LCA.

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