Browsing by Author "Misselbrook, T.H."
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- Ammonia and greenhouse gas emissions from slatted and solid floors in dairy cattle houses: A scale model studyPublication . Pereira, J.; Fangueiro, D.; Misselbrook, T.H.; Chadwick, D.R.; Coutinho, J.; Trindade, H.Dairy cattle are usually housed in naturally ventilated houses where removal of excreta is periodically performed. The aim of this controlled study was to compare the effect of two floor designs and three air temperatures (5, 15 and 25 C) on NH3, N2O, CH4 and CO2 emissions arising from cattle excreta deposition to the floor. Two scale models were built to simulate a level solid floor without urine drainage, and a slatted concrete floor. Following application of a mixture of urine and faeces, these two floor type models were subjected to a constant airflow rate (12.5 exchanges h 1 ) and gaseous emissions were measured over a 72-h period. Emissions of NH3, N2O, CO2 and CH4 increased significantly with air temperature with both floor type models and emissions of NH3, N2O and CO2 were significantly greater from the solid floor relative to the slatted floor at all temperatures considered. The cumulative NH3 (27e66% of total N applied) and CO2 (<19% of total C applied) emissions were greater from the solid floor than from the slatted floor (by 36% and 44%, respectively). The cumulative N2O (<0.1% of total N applied) and CH4 (<0.4% of total C applied) emissions were relatively low and CH4 values did not differ significantly between treatments. Cumulative greenhouse gas emissions (as CO2-equivalents) increased significantly with temperature but did not differ between the floor types.
- Ammonia emissions from dairy cattle buildings and outdoor concrete yards under the Mediterranean conditions of NW PortugalPublication . Pereira, J.; Misselbrook, T.H.; Chadwick, D.R.; Coutinho, J.; Trindade, H.Around 75% of European ammonia emissions comes from livestock production and emissions occur at all stages of manure management. Ammonia emissions have never been measured in commercial dairy cattle houses in Portugal. The objective of our study was to evaluate NH3 emissions for the main types of dairy cattle buildings naturally ventilated and outdoor concrete yards in NW Portugal.
- Ammonia emissions from naturally ventilated dairy cattle buildings and outdoor concrete yards in PortugalPublication . Pereira, J.; Misselbrook, T.H.; Chadwick, D.R.; Coutinho, J.; Trindade, H.There is a lack of information on ammonia (NH3) emissions from cattle housing systems in Mediterranean countries, with most published data deriving from NW Europe. An investigation was carried out in NW Portugal to quantify NH3 emissions for the main types of dairy cattle buildings in Portugal, i.e. naturally ventilated buildings and outdoor concrete yards, and to derive robust emission factors (EFs) for these conditions and compare with EFs used elsewhere in Europe. Measurements were made throughout a 12-month period using the passive flux sampling method in the livestock buildings and the equilibrium concentration technique in outdoor yards. The mean NH3 emission factor for the whole housing system (buildings þ outdoor yards) was 43.7 g NH3eN LU 1 day 1 and for outdoor concrete yards used by dairy cattle was 26.6 g NH3eN LU 1 day 1 . Expressing NH3 emission in terms of the quantity of liquid milk produced gave similar values across the three dairy farms studied (with a mean of 2.3 kg N ton-milk 1 produced) and may have advantages when comparing different farming systems. In dairy houses with outdoor yards, NH3 emissions from the yard area contributed to 69e92% of total emissions from this housing system. Emissions were particularly important during spring and summer seasons from outdoor yards with NH3 emitted in this period accounting for about 72% of annual emissions from outdoor yards. Mean NH3 emission factors derived for this freestall housing system and outdoor concrete yards used by dairy cattle in Portugal were higher than those measured in northern Europe. In addition, values of animal N excretion estimated in this study were greater than official National standard values. If these emissions are typical for Portuguese dairy systems, then the current National inventory underestimates emissions from this source in NW of Portugal, because of the use of lower standard values of N excretion by dairy cattle.
- Effect of cattle slurry pre-treatment by separation and addition of nitrification inhibitors on gaseous emissions and N dynamics: A laboratory studyPublication . Pereira, J.; Fangueiro, D.; Chadwick, D.R.; Misselbrook, T.H.; Coutinho, J.; Trindade, H.The application of untreated or treated animal manure to soils can result in increased N and C gaseous emissions contributing to ecosystem change and global warming. In the present study, dairy cattle slurry (liquid manure) was subjected first to pre-treatment by separation using a screw press to obtain a liquid (LF) and a solid fraction (SF). Then, the different fractions and the whole slurry (WS) were combined with two nitrification inhibitors (NI), dicyandiamide (DCD) or 3,4-dimethylpyrazole phosphate (DMPP), were applied to soil to assess the effect of slurry treatment by separation and NI addition on soil N dynamics and CH4, CO2, NH3, NO and N2O emissions. The WS and the two slurry fractions, combined or not with DCD or DMPP, were applied to soil at an equivalent field dosage of 120 kg total N haÿ1 . Controls including a soil only, soil–DCD and soil–DMPP treatments were also included. The mixtures were incubated for 93-d at 20 °C. Results obtained show that NI inhibited nitrification between 16 and 30-d in WS and LF, with DMPP having a longer effect over time compared to DCD. There was no significant effect of NI on nitrification for the SF treatment. Nitrification inhibitors did not significantly affect (P > 0.05) the CH4, CO2 and N2O emissions, but significantly decreased (P < 0.05) NO emissions. Furthermore, the two NIs had a similar effect on gaseous emissions. Throughout the entire experiment, the greatest amount of NO was released from the LF treatment (without NI), while the greatest amount of N2O was released from the SF treatment. Slurry separation had no impact on N emissions, while the combination of this process with one of the two NI led to a small reduction in total N emissions.
- Effect of solid and slatted floors and temperature on ammonia and GHG emissions in a scale model of dairy cattle housesPublication . Pereira, J.; Misselbrook, T.H.; Chadwick, D.R.; Coutinho, J.; Trindade, H.Dairy cattle are usually housed in naturally ventilated dairy houses, in witch the presence of urine and faeces, during a few hours or some days, lead to gaseous emissions. The aim of this study was to evaluate, at a scale model, the effect of a solid and a slatted floor at different air temperatures on NH3 and greenhouse gas (GHG) emissions (N2O, CO2 and CH4).
- Effects of a urease inhibitor and aluminium chloride alone or combined with a nitrification inhibitor on gaseous N emissions following soil application of cattle urinePublication . Pereira, J.; Barneze, A.S.; Misselbrook, T.H.; Coutinho, J.; Moreira, N.; Trindade, H.Addition to soil of separated cattle-urine obtained from housing with urine-faeces segregation systems is an important source of gaseous nitrogen (N) emissions. This study aimed to evaluate the effect of adding different concentrations of the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) and aluminium chloride (AlCl3), alone or combined with the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP), on gaseous N losses and N transformations in soil amended with cattle-urine. Using laboratory incubations soil was amended with cattle-urine (200 kg total N ha!1 ) containing NBPT (0.1 or 1.0%) or AlCl3 (0.5 or 1.0%) either as a single additive or combined with 0.5% DMPP. Three additional treatments were included: soil only (Control), soil amended only with cattle-urine and soil amended with cattle-urine and DMPP. The addition of NBPT at 1% significantly delayed urea hydrolysis during the first 4- d after urine application comparatively to treatments receiving AlCl3. Nitrification was inhibited by addition of DMPP, with no further effect (P > 0.05) when DMPP was combined with NBPT or AlCl3. The AlCl3 treatment had no effect on urea hydrolysis or nitrification. The combination of DMPP with NBPT or AlCl3 increased (P < 0.05) NH3 emissions and reduced (P < 0.05) NO and N2O emissions compared with urine alone. It was concluded that NBPT was more effective at reducing gaseous N emissions from cattle-urine applications than AlCl3, and that NBPT alone was more effective than NBPT combined with DMPP. No advantages were gained from the combination of one of these additives with DMPP on total gaseous N emissions
- Effects of temperature and dairy cattle excreta characteristics on ammonia emissions from a simulated concrete floorPublication . Pereira, J.; Misselbrook, T.H.; Chadwick, D.R.; Coutinho, J.; Trindade, H.In warm climate areas, such as the Mediterranean region, significant amounts of ammonia may be released to the atmosphere from urine and faeces deposited in concrete floor areas of dairy cattle housing systems. In many farms these concrete areas are shared by cattle of different ages and at different stages of the production cycle. The objectives of our study were to assess the effects of temperature and of excreta characteristics (i.e. from heifers, dry cows and lactating cows) on ammonia emissions, using a laboratory system simulating a dairy house concrete floor.
- Effects of temperature and dairy cattle excreta characteristics on potential ammonia and greenhouse gas emissions from housing: A laboratory studyPublication . Pereira, J.; Misselbrook, T.H.; Chadwick, D.R.; Coutinho, J.; Trindade, H.Dairy cattle housing is a significant source of NH3 and GHG emissions to atmosphere. However, the climate, temperature in particular, and the characteristics of the excreta of the housed cattle, may have a strong influence on the magnitude of such emissions. The objectives were to assess the effects of temperature and excreta characteristics of heifers, dry cows and lactating cows on potential NH3, N2O, CO2 and CH4 emissions. The experiment was conducted using laboratory chambers where constant amounts of urine and faeces were applied to a concrete floor. Potential NH3 and GHG emissions were measured over 120-h following application at 5, 15, 25 and 35 C. Increasing temperature promoted a significant increase in NH3 emissions. At temperatures 15 C, total NH3 emissions accounted for more than 100% of the ureaeN content of the urine for the three dairy cattle types, indicating that other organic N compounds of urine and faeces are an important source of NH3. The cumulative amount of N2O released did not vary significantly with temperature and ranged from 1 to 2% of total N deposited. Cumulative CO2 emissions were ca. 14e58% of total C deposited and the cumulative CH4 emissions were significantly higher at 25 C than at all other temperatures. It was concluded that increasing temperature from 5 to 35 C significantly increased potential NH3, CO2 and CH4 emissions but did not significantly influence N2O emissions. Also, the diet supplied to lactating cows led to significantly higher NH3, N2O and CO2 emissions relative to heifers and dry cows
- Influence of cattle slurry treatment by separation and nitrification inhibitors addition on N dynamics and N2O emissions after soil applicationPublication . Pereira, J.; Fangueiro, D.; Chadwick, D.R.; Misselbrook, T.H.; Coutinho, J.; Trindade, H.Application of cattle slurry to agricultural soils results in increased nitrogen losses to air and water due to nitrification and denitrification processes. The aim of this study was to evaluate the effect of addition to soil of different fractions of cattle slurry combined with two nitrification inhibitors (NI), dicyandiamide (DCD) or 3,4-dimethylpyrazole phosphate (DMPP) on soil N dynamics and N2O emissions.