Investigation of ammonia emissions from Austrian agriculture and means for reduction
Abstract
Sustainable agriculture must aim at reducing NH3, N2O and CH4 emissions. The research project aimed at quantifying emission rates from animal husbandry under conditions that are typical of Austrian agriculture. All stages of the manure management continuum were included in the measurements: housing, storage and manure application. The following emission sources were investigated: tied house for dairy cattle, sloped floor house for dairy cattle, sloped floor house for beef cattle, farmyard manure storage, composting and field application. A high resolution FTIR spectroscope analysed gas concentrations of NH3, N2O and CH4. In the forced ventilated animal houses, air flow was determined in the central exhaust opening. Air flow over diffuse sources was quantified with a large open dynamic chamber. Emissions from a tied house for dairy cattle (straw and slurry based system) were measured at the research station Gumpenstein (Austrian alpine region). Measurements were repeated several times in course of the year. NH3, N2O and CH4 emissions did not show a significant difference between the slurry and the straw based system. About 80 % of net total CH4 emissions came from dairy cow enteric fermentation. C. 20 % of methane emissions resulted from microbiological processes in the manure. NH3 emissions were on a low level: 5.7 (slurry based system) and 5.8 (straw based system) g NH3 LU-1 day-1. The manured area in a tied system is small which results in low NH3 emissions. N2O emissions amounted to 600 mg N2O LU-1 day-1. Emissions from a sloped floor housing system for dairy cattle were only quantified under warm summer conditions. They therefore represent the upper limit of emission rates from that system. Methane emissions (without emissions from enteric fermentation) were 23.8 g CH4 LU-1 day-1. 16.6 g NH3 LU-1 day-1 and 2.0 g N2O LU-1 day-1 were lost. Emissions from a sloped floor house for male beef cattle were measured at the research station Gumpenstein (Austrian alpine region). Measurements were repeated several times in course of the year. The stall was alternately operated with much litter (5 kg straw LU-1 day-1) and little litter (2.5 kg straw LU-1 day-1). Nearly all of the methane emissions resulted from enteric fermentation of the beef cattle. When only 2.5 kg straw LU-1 day-1 were used, NH3 emissions amounted to 498 mg NH3 LU-1 h-1. With 5 kg straw LU-1 day-1 NH3 emissions were reduced to 370 mg NH3 LU-1 h-1. The use of more straw was effective in mitigating NH3 emissions. In the house, the treatment "little straw" emitted less N2O than the treatment "much straw". During farmyard manure storage, N2O emissions from "much straw" were smaller than from "little straw". In total (house and storage), "much straw" emitted 5.95 g N2O t-1 and "little straw" emitted 17.13 g N2O t-1. Straw is a cheap and effective means to reduce emissions from a sloped floor house for beef cattle. NH3, N2O and CH4 emissions were quantified from aerobic composting, and anaerobic stacking of farmyard manure and after farmyard manure application.
www.nitro-soil.atProject staff
Josef Boxberger
o.Univ.Prof.i.R. Dipl.-Ing.Dr.nat.techn. Josef Boxberger
josef.boxberger@boku.ac.at
Project Leader
01.06.1994 - 30.03.1998
Barbara Amon
Priv.Doz.Dr. Barbara Amon
barbara.amon@boku.ac.at
Project Staff
01.06.1994 - 30.03.1998
Adolf Zaussinger
em.Univ.Prof. Dipl.-Ing.Dr.nat.techn. Adolf Zaussinger
adolf.zaussinger@boku.ac.at
Project Staff
01.06.1994 - 30.03.1998
BOKU partners
External partners
Technical University of Munich
Dr. Andreas Gronauer
partner
Federal Research Centre for Agriculture_x000D_
Prof. Dr. Axel Munack
partner
Bundesanstalt für alpenländische Landwirtschaft
partner
Funder
