Emissions of the indirect greenhouse gases NH3 and NOx from Australian beef cattle feedlots

2008 ◽  
Vol 48 (2) ◽  
pp. 213 ◽  
Author(s):  
O. T. Denmead ◽  
D. Chen ◽  
D. W. T. Griffith ◽  
Z. M. Loh ◽  
M. Bai ◽  
...  

Emissions of indirect greenhouse gases, notably the nitrogen gases ammonia (NH3) and the odd oxides of nitrogen (NOx), play important roles in the greenhouse story. Feedlots are intense, but poorly quantified, sources of atmospheric NH3 and although production of NOx is to be expected in feedlots, rates of NOx emission are virtually unknown. In the atmosphere, these gases are involved in several transformations, but eventually return to the earth in gaseous or liquid form and can then undergo further transformations involving the formation and emission of the direct greenhouse gas nitrous oxide (N2O). The IPCC Phase II guidelines estimate that indirect N2O emissions due to atmospheric deposition of N compounds formed from NH3 and NOx could be ~14% of the direct emissions from agricultural soils or from animal production systems. IPCC recommends that these indirect emissions be accounted for in making inventory estimates of N2O emission. This paper is a preliminary report of emissions of NH3 and NOx from two Australian feedlots determined with micrometeorological techniques. Emissions of nitrogen gases from both feedlots were dominated by emissions of NH3. The average NH3 emission rate over both feedlots in winter was 46 g N/animal.day, while that of NOx was less than 1% of that rate at 0.36 g N/animal.day. It was apparent that NH3 release was governed by the wetness of the surface. Rates of emission from the feedlot with the wetter surface were almost three times those from the other. The IPCC default emission factor for the combined emission of NH3 and NOx from livestock is 0.2 kg N/kg N excreted, but in our work, the emission factor was 0.59 kg N/kg N excreted. Potential emissions of N2O due to NH3 and NOx deposition were estimated to be of the same magnitude as the direct N2O emissions, the sum of direct and potential indirect amounting to ~3 g N2O-N/animal.day. If applied nationally, this would represent a contribution of N2O from Australian feedlots of 533Gg CO2-e or 2.2% of all Australian N2O emissions.

2018 ◽  
Vol 18(33) (2) ◽  
pp. 70-81
Author(s):  
Antoni Faber ◽  
Zuzanna Jarosz

The aim of the research was to verify the N2O direct and NH3 emission factors adopted in national inventories, and to estimate the direct and indirect N2O emissions in cultivation systems increasing carbon sequestration. Simulations were performed using the DNDC model for NUTS2 and Poland with the use of twenty-year series of meteorological data. It was found that the simulated direct emission of nitrous oxide for Poland was in line with the adopted emission factor. The simulated ammonia emission was greater than the assumed emission factor. Use in simulations of cultivation systems increasing the sequestration of organic carbon, such as conservation system and conventional system with manure fertilization, increased: surface leaching and runoff of nitrogen as well as direct and indirect N2O emission. The increase of these emissions must be compensated with an allowance increase in the amount of sequestered organic carbon in the soil if the greenhouse gas emissions balance is to be negative.


2008 ◽  
Vol 5 (5) ◽  
pp. 1215-1226 ◽  
Author(s):  
D. Weymann ◽  
R. Well ◽  
H. Flessa ◽  
C. von der Heide ◽  
M. Deurer ◽  
...  

Abstract. We investigated the dynamics of denitrification and nitrous oxide (N2O) accumulation in 4 nitrate (NO−3) contaminated denitrifying sand and gravel aquifers of northern Germany (Fuhrberg, Sulingen, Thülsfelde and Göttingen) to quantify their potential N2O emission and to evaluate existing concepts of N2O emission factors. Excess N2 – N2 produced by denitrification – was determined by using the argon (Ar) concentration in groundwater as a natural inert tracer, assuming that this noble gas functions as a stable component and does not change during denitrification. Furthermore, initial NO−3 concentrations (NO−3 that enters the groundwater) were derived from excess N2 and actual NO−3 concentrations in groundwater in order to determine potential indirect N2O emissions as a function of the N input. Median concentrations of N2O and excess N2 ranged from 3 to 89 μg N L−1 and from 3 to 10 mg N L−1, respectively. Reaction progress (RP) of denitrification was determined as the ratio between products (N2O-N + excess N2) and starting material (initial NO−3 concentration) of the process, characterizing the different stages of denitrification. N2O concentrations were lowest at RP close to 0 and RP close to 1 but relatively high at a RP between 0.2 and 0.6. For the first time, we report groundwater N2O emission factors consisting of the ratio between N2O-N and initial NO−3-N concentrations (EF1). In addition, we determined a groundwater emission factor (EF2) using a previous concept consisting of the ratio between N2O-N and actual NO−3-N concentrations. Depending on RP, EF(1) resulted in smaller values compared to EF(2), demonstrating (i) the relevance of NO−3 consumption and consequently (ii) the need to take initial NO−3-N concentrations into account. In general, both evaluated emission factors were highly variable within and among the aquifers. The site medians ranged between 0.00043–0.00438 for EF(1) and 0.00092–0.01801 for EF(2), respectively. For the aquifers of Fuhrberg and Sulingen, we found EF(1) median values which are close to the 2006 IPCC default value of 0.0025. In contrast, we determined significant lower EF values for the aquifers of Thülsfelde and Göttingen. Summing the results up, our study supports the substantial downward revision of the IPCC default EF5-g from 0.015 (1997) to 0.0025 (2006).


2009 ◽  
Vol 6 (3) ◽  
pp. 5305-5337 ◽  
Author(s):  
M. Maljanen ◽  
P. Virkajärvi ◽  
J. Hytönen ◽  
M. Öquist ◽  
T. Sparrman ◽  
...  

Abstract. Agricultural soils are the most important sources for the greenhouse gas nitrous oxide (N2O), which is produced and emitted from soil also at low temperatures. The processes behind emissions at low temperatures are still poorly known. To simulate the effects of a reduction in snow depth on N2O emission in warming climate, snow pack was removed from three different agricultural soils (sand, mull, peat). Removal of snow lowered soil temperature and increased the extent and duration of soil frost which led to enhanced N2O emissions during freezing and thawing events in sand and mull soils. The cumulative emissions during the first year when snow was removed over the whole winter were 0.25, 0.66 and 3.0 g N2O-N m−2 yr−1 in control plots of sand, mull and peat soils, respectively. Without snow cover the respectively cumulative emissions were 0.37, 1.3 and 3.3 g N2O-N m−2 yr−1. Shorter snow manipulation during the second year did not increase the annual emissions. Only 20% of the N2O emission occurred during the growing season. Thus, highlighting the importance of the winter season for this exchange and that the year-round measurements of N2O emissions from boreal soils are integral for estimating their N2O source strength. N2O accumulated in the frozen soil during winter and the soil N2O concentration correlated with the depth of frost but not with the winter N2O emission rates per se. Also laboratory incubations of soil samples showed high production rates of N2O at temperatures below 0°C, especially in the sand and peat soils.


2020 ◽  
Vol 12 (24) ◽  
pp. 10528
Author(s):  
Robert Impraim ◽  
Anthony Weatherley ◽  
Trevor Coates ◽  
Deli Chen ◽  
Helen Suter

Lignite amendment of livestock manure is considered a viable ammonia (NH3) emission mitigation technique. However, its impact on the subsequent composting of the manure has not been well studied. This work compared changes in biochemical parameters (e.g., organic matter loss and nitrogen (N) transformation) and also the emissions of NH3 and greenhouse gases (GHGs) between lignite-amended and unamended cattle manure during forced aeration composting. Amending manure with lignite did not alter the time to compost stability despite delaying the onset of the thermophilic temperatures. Lignite treatments retained N in the manure by suppressing NH3 loss by 35–54%, resulting in lignite-amended manure composts having 10–19% more total N than the unamended compost. Relative to manure only, lignites reduced GHG emissions over the composting period: nitrous oxide (N2O) (58–72%), carbon dioxide (CO2) (12–23%) and methane (CH4) (52–59%). Low levels of CH4 and N2O emissions were observed and this was attributed to the continuous forced aeration system used in the composting. Lignite addition also improved the germination index of the final compost: 90–113% compared to 71% for manure only. These findings suggest that lignite amendment of manure has the potential to improve the quality of the final compost whilst mitigating the environmental release of NH3 and GHGs.


2012 ◽  
Vol 9 (3) ◽  
pp. 1085-1097 ◽  
Author(s):  
G. Vilain ◽  
J. Garnier ◽  
P. Passy ◽  
M. Silvestre ◽  
G. Billen

Abstract. Agricultural basins are the major source of N2O emissions, with arable land accounting for half of the biogenic emissions worldwide. Moreover, N2O emission strongly depends on the position of agricultural land in relation with topographical gradients, as footslope soils are often more prone to denitrification. The estimation of land surface area occupied by agricultural soils depends on the available spatial input information and resolution. Surface areas of grassland, forest and arable lands were estimated for the Orgeval sub-basin using two cover representations: the pan European CORINE Land Cover 2006 database (CLC 2006) and a combination of two databases produced by the IAU IDF (Institut d'Aménagement et d'Urbanisme de la Région d'Île-de-France), the MOS (Mode d'Occupation des Sols) combined with the ECOMOS 2000 (a land-use classification). In this study, we have analyzed how different land-cover representations influence and introduce errors into the results of regional N2O emissions inventories. A further introduction of the topography concept was used to better identify the critical zones for N2O emissions, a crucial issue to better adapt the strategies of N2O emissions mitigation. Overall, we observed that a refinement of the land-cover database led to a 5 % decrease in the estimation of N2O emissions, while the integration of the topography decreased the estimation of N2O emissions up to 25 %.


Soil Research ◽  
2003 ◽  
Vol 41 (3) ◽  
pp. 381 ◽  
Author(s):  
Cecile A. M. de Klein ◽  
Louise Barton ◽  
Robert R. Sherlock ◽  
Zheng Li ◽  
Roger P. Littlejohn

The Intergovernmental Panel on Climate Change methodology estimates that over 50% of total nitrous oxide (N2O) emissions in New Zealand derive from animal excreta-N deposited during grazing. The emission factor for excreta-N as used by this methodology has an important impact on New Zealand's total N2O inventory. The objectives of this study were to refine the N2O emission factor for urine by simultaneously measuring N2O emissions from 5 pastoral soils of different drainage class, in 3 different regions in New Zealand following a single application of urine; plus test various aspects of the soil cover method for determining emission factors. Cow urine and synthetic urine was applied to pastoral soils in autumn 2000 and N2O emissions were measured using closed flux chambers at regular intervals for 4–18 months following application. The N2O emission factors for cow urine estimated for the first 4 months after urine application varied greatly depending on rainfall and soil drainage class, and ranged from 0.3 to 2.5% of the urine-N applied, suggesting that adopting a single emission factor for New Zealand may be inappropriate. The largest emission factor was found in a poorly drained soil, and the lowest emission factor was found in a well-drained stony soil. Ongoing measurements on one of the soils resulted in an increase in emission factors as the N2O emissions had not reached background levels 4 months after urine application. To characterise urine-induced N2O emissions, we recommend measurements continue until N2O emissions from urine-amended soil return to background levels. Furthermore, we recommend using real animal urine rather than synthetic urine in studies when determining the N2O emission factor for urine.


2009 ◽  
Vol 6 (11) ◽  
pp. 2461-2473 ◽  
Author(s):  
M. Maljanen ◽  
P. Virkajärvi ◽  
J. Hytönen ◽  
M. Öquist ◽  
T. Sparrman ◽  
...  

Abstract. Agricultural soils are the most important sources for the greenhouse gas nitrous oxide (N2O), which is produced and emitted from soils also at low temperatures. The processes behind emissions at low temperatures are still poorly known. Snow is a good insulator and it keeps soil temperature rather constant. To simulate the effects of a reduction in snow depth on N2O emission in warming climate, snow pack was removed from experimental plots on three different agricultural soils (sand, mull, peat). Removal of snow lowered soil temperature and increased the extent and duration of soil frost in sand and mull soils. This led to enhanced N2O emissions during freezing and thawing events. The cumulative emissions during the first year when snow was removed over the whole winter were 0.25, 0.66 and 3.0 g N2O-N m−2 yr−1 in control plots of sand, mull and peat soils, respectively. In the treatment plots, without snow cover, the respective cumulative emissions were 0.37, 1.3 and 3.3 g N2O-N m−2 yr−1. Shorter snow manipulation during the second year did not increase the annual emissions. Only 20% of the N2O emission occurred during the growing season. Thus, these results highlight the importance of the winter season for this exchange and that the year-round measurements of annual N2O emissions from boreal soils are integral for estimating their N2O source strength. N2O accumulated in the frozen soil during winter and the soil N2O concentration correlated with the depth of frost but not with the winter N2O emission rates per se. Also laboratory incubations of soil samples showed high production rates of N2O at temperatures below 0°C, especially in the sand and peat soils.


Soil Research ◽  
2020 ◽  
Vol 58 (2) ◽  
pp. 198 ◽  
Author(s):  
Janquieli Schirmann ◽  
Diego Fernandes de Bastos ◽  
Douglas Adams Weiler ◽  
Murilo G. Veloso ◽  
Jeferson Dieckow ◽  
...  

Native grassland supports extensive livestock production in the Pampas of South America, but the impact of cattle excreta on nitrous oxide (N2O) emissions remains unknown in this biome. The objective of this study was to determine the N2O emission factor (EF-N2O, % of N applied that is emitted as N2O) for urine and dung from beef cattle grazing on native grasslands. A field trial was conducted under low and moderate forage allowances (FA4 and FA12; i.e. 4 and 12 kg dry matter/100 kg live weight respectively) during the 30th year of a long-term grassland experiment on a Typic Paleudult in South Brazil. Urine and dung were applied onto separate patches, at rates equivalent to one average urination or defecation; and N2O fluxes were monitored with closed static chambers over 338 days. In adjacent microplots receiving the same excreta treatment, water-filled pore space, nitrate, ammonium and extractable dissolved organic carbon were monitored in the top 0.1 m of soil. Averaged across the forage allowances, daily soil N2O fluxes were low in the control without excreta (1.3 g N ha–1), but increased upon application of dung (3.8 g N ha–1) and urine (66 g N ha–1). The annual N2O emission and the EF-N2O for urine were greater under FA12 than FA4, but no difference was observed for dung. The positive relationships between N2O-N emissions and ammonium intensity and nitrate intensity suggest that N2O may have been produced concurrently by nitrification, nitrifier/denitrification and denitrification. On average, the EF-N2O was almost 10 times higher for urine than for dung (0.74% vs 0.08%), both much lower than the IPCC’s Tier 1 default value of 2%. Our findings reinforce the need for disaggregating the EF-N2O for urine and dung and of revising the IPCC’s Tier 1 EF-N2O.


2013 ◽  
Vol 43 (3) ◽  
pp. 322-338 ◽  
Author(s):  
Diana Signor ◽  
Carlos Eduardo Pellegrino Cerri

The greenhouse gases concentration in the atmosphere have significantly increased since the beginning of the Industrial Revolution. The most important greenhouse gases are CO2, CH4 and N2O, with CH4 and N2O presenting global warming potentials 25 and 298 times higher than CO2, respectively. Most of the N2O emissions take place in soils and are related with agricultural activities. So, this review article aimed at presenting the mechanisms of N2O formation and emission in agricultural soils, as well as gathering and discussing information on how soil management practices may be used to reduce such emissions. The N2O formation in the soil occurs mainly through nitrification and denitrification processes, which are influenced by soil moisture, temperature, oxygen concentration, amount of available organic carbon and nitrogen and soil C/N ratio. Among these factors, those related to soil could be easily altered by management practices. Therefore, understanding the processes of N2O formation in soils and the factors influencing these emissions is fundamental to develop efficient strategies to reduce N2O emissions in agricultural soils.


2011 ◽  
Vol 134 (1) ◽  
Author(s):  
Hailin Li ◽  
W. Stuart Neill ◽  
Hongsheng Guo ◽  
Wally Chippior

This paper presents the oxides of nitrogen (NOx) and nitrous oxide (N2O) emission characteristics of a Cooperative Fuel Research (CFR) engine modified to operate in homogeneous charge compression ignition (HCCI) combustion mode. N-heptane was used as the fuel in this research. Several parameters were varied, including intake air temperature and pressure, air/fuel ratio (AFR), compression ratio (CR), and exhaust gas recirculation (EGR) rate, to alter the HCCI combustion phasing from an overly advanced condition where knocking occurred to an overly retarded condition where incomplete combustion occurred with excessive emissions of unburned hydrocarbons (UHC) and carbon monoxide (CO). NOx emissions below 5 ppm were obtained over a fairly wide range of operating conditions, except when knocking or incomplete combustion occurred. The NOx emissions were relatively constant when the combustion phasing was within the acceptable range. NOx emissions increased substantially when the HCCI combustion phasing was retarded beyond the optimal phasing even though lower combustion temperatures were expected. The increased N2O and UHC emissions observed with retarded combustion phasing may contribute to this unexpected increase in NOx emissions. N2O emissions were generally less than 0.5 ppm; however, they increased substantially with excessively retarded and incomplete combustion. The highest measured N2O emissions were 1.7 ppm, which occurred when the combustion efficiency was approximately 70%.


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