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The aim of this study was to review research papers with gas emission data from livestock buildings that were published between 1997 and 2015. The review focused on three gases: NH₃, N₂O and CH₄ and two animal species: pigs and dairy cows. The results of the review are presented in different units, which makes it difficult to compare the data. For this purpose, the gas emission factors were converted to 1 LU (livestock unit = 500 kg). The median of NH₃ emission factors for pigs (45.6 g·day⁻¹·LU⁻¹) was almost twice that of dairy cows (26.7 g·day⁻¹·LU⁻¹). For N₂O the emission factor median for pigs (3.2 g·day⁻¹·LU⁻¹) was more than twice that of dairy cows (1.5 g·day⁻¹·LU⁻¹). Also for CH₄ , the median of emission factors for dairy cows (302.5 g·day⁻¹·LU⁻¹) was more than three times higher than the value for pigs (85 g·day⁻¹·LU⁻¹). The variation in the gas emission factor values for pigs and dairy cows is large. This may be due to the following reasons: geographical location, animal species, feed composition, housing and ventilation system or time of measurements. Therefore, there is a need to continue gas emission monitoring research in order to more precisely determine the values of these gas emission factors for pig and dairy production facilities. Measurement procedures should be standardized including the number of measuring days/months, frequency of sampling, measurement equipment and unit of gas emission factor units. Using common methodology for measuring gas emission will allow better comparisons between emission factors for livestock buildings and housing systems and between countries and animal species.
The aim of this study was to review papers about odor emissions from livestock production published between 1997 and 2013. The study concerned three animal species: poultry, swine, and dairy cattle. The results of the research are presented in different units, making it difficult to compare them. For this purpose, the odor emission factors were converted with respect to 1 LU (livestock unit=500 kg). The calculated mean odor emission factor was greatest for poultry, followed by swine and dairy cattle, but the coefficient of variation for all animal species was high. Such a variability could be caused by weather and microclimate conditions, the housing system, and measurement methods. Therefore, it is reasonable to continue the odor emission research in order to precisely determine the values of odor emission factors. It is also necessary to develop the common unified methods for air sample collecting as well as unified unit of odor emission factor to make odor emission factors more comaparable. It may be useful in establishing any legal regulations on this subject.
In the literature, there are many studies on greenhouse gas and ammonia emissions from dairy barns, however their values are varied. The national inventory of gaseous air pollutants is performed by using theoretical standard emission factors according to the international methodology: Intergovernmental Panel on Climate Change (IPCC) and European Monitoring and Evaluation Programme (EMEP). The aim of the study was to determine the values of greenhouse gases (CH₄, N₂O) and ammonia emission factors during pilot research in commercial barns. The study was conducted in six livestock buildings for dairy cows located in the Wielkopolska Voivodship. The studied barns differed in a construction, the type of resting area and the manure removal system. The 18 daily measurements were made, the 3 test series in each barn. The mean calculated values of greenhouse gases and ammonia emission factors were: 135±47 kg·yr⁻¹·cow⁻¹ (103.4±35.9 kg·yr⁻¹·LU⁻¹) for CH4, 0.91±0.74 kg·yr⁻¹·cow⁻¹ (0.70±0.57 kg·yr⁻¹·LU⁻¹) for N2O and 8.9±5.2 kg·yr⁻¹·cow⁻¹ (6.9±3.9 kg·yr⁻¹·LU⁻¹) for NH₃ The converted on 1 LU (livestock unit = 500 kg), CH₄, N₂O and NH₃ emission factors differed from factors used by National Centre for Emission Management in 2013. The determined factors in this study were lower about 20% for CH₄, higher about 21% for N₂O and lower about 67% for NH₃.
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