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.

1 Bookmark
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A combination of stable isotope and acetylene (0.01% v/v) inhibition techniques were used for the first time to determine N2O production during denitrification, autotrophic nitrification and heterotrophic nitrification in a fertilised (200 kg N ha−1) silt loam soil at contrasting (20–70%) water-filled pore space (WFPS). 15N-N2O emissions from 14NH415NO3 replicates were attributed to denitrification and 15N-N2O from 15NH415NO3 minus that from 14NH415NO3 replicates was attributed to nitrification and heterotrophic nitrification in the presence of acetylene, as there was no dissimilatory nitrate reduction to ammonium or immobilisation and remineralisation of 15N-NO3−. All of the N2O emitted at 70% WFPS (31.6 mg N2O-N m−2 over 24 days; 1.12 μg N2O-N g dry soil−1; 0.16% of N applied) was produced during denitrification, but at 35–60% WFPS nitrification was the main process producing N2O, accounting for 81% of 15N-N2O emitted at 60% WFPS, and 7.9 μg 15N-N2O m−2 (0.28 ng 15N-N2O g dry soil−1) was estimated to be emitted over 7 days during heterotrophic nitrification in the 50% WFPS treatment and accounted for 20% of 15N-N2O from this treatment. Denitrification was the predominant N2O-producing process at 20% WFPS (2.6 μg 15N-N2O m−2 over 7 days; 0.09 ng 15N-N2O g dry soil−1; 85% of 15N-N2O from this treatment) and may have been due to the occurrence of aerobic denitrification at this WFPS. Our results demonstrate the usefulness of a combined stable isotope and acetylene approach to quantify N2O emissions from different processes and to show that several processes may contribute to N2O emission from agricultural soils depending on soil WFPS.
    Biology and Fertility of Soils 08/2005; 41(6):379-388. · 3.40 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Optimising the implementation of energy used in agriculture is an important objective in the "Climate Action and Renewable Energy Package" adopted by the European Union. Therefore, studying the management of different cropping systems represents a good method to optimise input requirements, yield and net energy supply. The aim of this study is to compare the energy use of a 12-year rainfed cropping system, located in Tuscany, Italy. The system is cultivated under two different management intensities: a conventional system (CS) and a low input system (LIS) for a six-year crop rotation that included sugar beet, durum wheat, sorghum, sunflower, and durum wheat. In the sixth year, the soil was set-aside. The results showed that crop yield and energy yield were not significantly affected by management intensities, whereas energy efficiency of the low input system increased significantly, by about 30%. Future research should include more crops and locations to obtain further information about the range of energy parameters and their long-term trends. Furthermore, could be interesting to evaluate the overall reduction of environmental impacts and production costs that could occur limiting the use of chemicals and adopting conservative soil tillage strategies.
    Energy 01/2010; · 4.16 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Biofuels could become increasingly important for agriculture; however there is growing concern regarding the possible environmental drawbacks due to the risks of increased inputs during crop cultivation. These risks need to be evaluated in order to assess the best management practices. In this study, a life cycle assessment (LCA) was carried out: (i) to evaluate the environmental impacts of three cropping systems characterized by different external input levels (low S1, medium S2 and high S3) applied to sunflower and maize, both in rotation with wheat, in a Mediterranean region; (ii) to estimate the environmental benefits of the optimization of cropping systems for energy management. Output–input ratio, net energy balance, global warming potential (GWP), eutrophication potential (EP) and acidification potential (AP) were used as LCA impact categories. Data from cropping systems (external input and crop yields) were collected from a long-term experiment carried out in the coastal plain of Tuscany; data regarding fertilizers, machinery and pesticide production were taken from literature. The results obtained showed S1 with the highest output–input ratios and the lowest impact for the selected impact categories. The other cropping systems S2 and S3 showed limited differences between them for all the impact categories evaluated. Fertilizer use and application, irrigation and machinery use caused most of the environmental impacts and energy consumption. The allocation procedure, showing residues as co-products, had a strong influence on the overall efficiency of agricultural systems.
    Biomass and Bioenergy 07/2012; 42:33-42. · 3.41 Impact Factor


Available from
May 19, 2014