Huella De Carbono

METHANE, NITROUS OXIDE AND AMMONIA EMISSIONS DURING STORAGE AND AFTER APPLICATION OF DAIRY CATTLE AND PIG SLURRY AND INFLUENCE OF SLURRY TREATMENT
Barbara Amon1, Vitaliy Kryvoruchko1, Gerhard Moitzi1, Thomas Amon1, Sophie Zechmeister-Boltenstern2,
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Department of Sustainable Agricultural Systems, Division of Agricultural Engineering, University of Natural Resources and Applied Life Sciences,Peter-Jordanstrasse 82, A1190 Wien; e-mail: barbara.amon@boku.ac.at Department of Forest Ecology and Soil Biology, Federal Office and Research Centre for Forests, Seckendorff-Gudent Weg 8, A-1131 Wien; e-mail: sophie.zechmeister@bfw.gv.at

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ABSTRACT Ammonia, methane and nitrous oxide emissions from the manure management continuum “storage” and “field application” were quantified under fieldconditions. Experiments included dairy cattle and pig slurry. Emissions were followed from untreated, separated, anaerobically digested, straw covered and aerated slurry. About 10 m3 slurry were stored in concrete tanks. Emission rates were determined with a large open-dynamic chamber and with high resolution FTIR spectrometry. Sampling frequency was high. No potential for ammonia abatement wasfound within the investigated slurry treatment options. Ammonia emissions mainly occurred after field application. Promising mitigation options are low trajectory application techniques and proper timing of application. Anaerobic digestion is an effective means to reduce greenhouse gas emissions. Straw cover and slurry aeration showed negative environmental effects. Keywords: biogas, slurryseparation, nitrous oxide, methane, manure management INTROCUCTION Manure management is a source for methane (CH4), nitrous oxide (N2O) and ammonia (NH3) emissions. CH4 and N2O emissions are estimated according to the “Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories” (IPCC 1997). It is assumed that manure has a maximum methane production potential (B0). B0 values for animal manureshave been measured under lab conditions. The IPCC guidelines give methane conversion factors (MCF) that estimate how much of the maximum methane production potential is realised when manure is stored on commercial farms. N2O emissions during storage and after application of animal manures are estimated with emission factors that give N2O losses as percentage of nitrogen excreted by the animal.Manure treatment options are not differentiated in the emission factors. B0 values, MCF, and emission factors for N2O are associated with considerable uncertainty. Mitigation options can only be proposed, if knowledge on emissions from manure management is improved. The influence of contrasting manure treatment options must be investigated. The research project aimed at finding slurry treatmentoptions that reduce ammonia and greenhouse gas emissions during slurry storage and after field application. Emissions during storage and after application were followed as it is important to

reduce net total emissions and avoid the swapping of emissions from one stage of the manure management continuum to the next. APPROACH NH3, CH4 and N2O during slurry storage were quantified in 10 m3 pilot scaleslurry tanks. The tanks were made from concrete and buried in the ground, with 5 cm of the wall above the soil surface (Fig. 1). Emissions of NH3, N2O and CH4 were quantified by moving a large open dynamic chamber on a slurry tank and collecting the emissions. Emissions of each variant were measured at least twice a week for several hours.

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5 slurry tanks, 2.5 mdepth and 2.5 m diameter each
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wooden rail large open dynamic chamber fresh air
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Fig. 1. Design of the experimental facility for quantifying emissions from slurry stores (Amon et al. 2002) The large open dynamic chamber determines the air flow over stored manure. It covers an area of...