Minimisation of N2O emissions from a plant-soil system under landfill leachate irrigation

The irrigation of a plant-soil system with landfill leachate should promote the formation of N2O due to the introduction of organic carbon and mineralized-N and the elevation of the moisture content. Laboratory incubation was performed to minimize N2O emissions from a leachate irrigated plant-soil system by manipulating leachate NH(4)(+)-N loading, moisture content, and soil type. A field investigation, consisting of three plots planted with Cynodon dactylon, Nerium indicum Mill, and Festuca arundinacea Schreb, was then conducted to select plant species. There was almost no difference in N2O emissions between soil moisture contents of 46% and 55% water-filled pore space (WFPS), while a sharp increase occurred at 70% WFPS. N2O fluxes were significantly correlated with leachate NH4(+)-N loading. Amongst the physiochemical characteristics of the selected nine soils, only soil pH was significantly correlated with N2O fluxes. Compared with fertilizers application in other ecosystems, N2O turnover rate from the plant-soil system under leachate irrigation was relatively lower. Therefore, avoiding high NH4(+)-N loadings and excessively wet conditions (<60% WFPS) and cultivating conifer plants of stronger sunlight penetration with less litter deposit on acidic sandy soil could minimize potential N2O emissions under leachate irrigation.     

Whole-year-round Observation of N<Subscript>2</Subscript>O Profiles in Soil: A Lysimeter Study

Despite many studies of the N₂O emission, there is a lack of knowledge on the role of subsoil for N₂O emission, particularly in sandy soils. To obtain insight into the entrapment, diffusion, convection and ebullition of N₂O in the soil, the N₂O concentration in the soil atmosphere was measured over a period of 1 year in 4 lysimeters (agricultural soil monoliths of 1 m2 × 2 m) at 30, 50, 80, 155, and 190 cm depth with altogether 86 gas probes. Additionally the N₂O emission into the atmosphere was measured in 20 closed chambers at the soil surface. Concurrently the soil temperature and soil water content were recorded in order to quantify their effects on the fate of N₂O in the soil. Results of the continuous measurements between January and December 2006 were: N₂O concentrations were highest in the deeper soil; maximum concentration was found at a depth of 80 cm, where the water content was high and the gas transport reduced. The highest N₂O concentration was recorded after ‘special events’ like snowmelt, heavy rain, fertilization, and grubbing. The combination of fertilization and heavy rain led to an increase of up to 2,700 ppb in the subsoil.     

N2O emission from a combined ex-situ nitrification and in-situ denitrification bioreactor landfill

A combined process comprised of ex-situ nitrification in an aged refuse bioreactor (designated as A bioreactor) and in-situ denitrification in a fresh refuse bioreactor (designated as F bioreactor) was constructed for investigating N₂O emission during the stabilization of municipal solid waste (MSW). The results showed that N₂O concentration in the F bioreactor varied from undetectable to about 130 ppm, while it was much higher in the A bioreactor with the concentration varying from undetectable to about 900 ppm. The greatly differences of continuous monitoring of N₂O emission after leachate cross recirculation in each period were primarily attributed to the stabilization degree of MSW. Moreover, the variation of N₂O concentration was closely related to the leachate quality in both bioreactors and it was mainly affected by the COD and COD/TN ratio of leachate from the F bioreactor, as well as the DO, ORP, and NO₃^?-N of leachate from the A bioreactor.     

Greenhouse gas emissions from landfill leachate treatment plants: A comparison of young and aged landfill

With limited assessment, leachate treatment of a specified landfill is considered to be a significant source of greenhouse gas (GHG) emissions. In our study, the cumulative GHG emitted from the storage ponds and process configurations that manage fresh or aged landfill leachate were investigated. Our results showed that strong CH₄ emissions were observed from the fresh leachate storage pond, with the fluxes values (2219–26,489 mg C m^?2 h^?1) extremely higher than those of N₂O (0.028–0.41 mg N m^?2 h^?1). In contrast, the emission values for both CH₄ and N₂O were low for the aged leachate tank. N₂O emissions became dominant once the leachate entered the treatment plants of both systems, accounting for 8–12% of the removal of N-species gases. Per capita, the N₂O emission based on both leachate treatment systems was estimated to be 7.99 g N₂O–N capita^?1 yr^?1. An increase of 80% in N₂O emissions was observed when the bioreactor pH decreased by approximately 1 pH unit. The vast majority of carbon was removed in the form of CO₂, with a small portion as CH₄ (<0.3%) during both treatment processes. The cumulative GHG emissions for fresh leachate storage ponds, fresh leachate treatment system and aged leachate treatment system were 19.10, 10.62 and 3.63 Gg CO₂ eq yr^?1, respectively, for a total that could be transformed to 9.09 kg CO₂ eq capita^?1 yr^?1.     

Nitrous Oxide Emissions from Two Riparian Ecosystems: Key Controlling Variables

Nitrous oxide (N₂O) emissions were measured weekly to fortnightly between April 2001 and March 2002 from two riparian ecosystems drainingdifferent agricultural fields. The fields differed in the nature of the crop grown and the amount of fertiliser applied. Soil water content and soil temperature were very important controls of N₂O emission rates, with a ‘threshold’ response at 24% moisture content (by volume) and 8 °C, below which N₂O emission was very low.N₂O fluxes were higher at the site that had receivedthe most fertiliser N, but NO₃ ^- was not a limiting factor at either site. There was also a ‘threshold’ effect of rainfall, in which major rainfall events (≥10 mm) triggered a pulse of high N₂O emission if none of the other environmental factors were limiting. These results suggest the existence of multiple controls on N₂O emissions operating at a range of spatial and temporal scales and that non-linear relationships, perhaps with a hierarchical structure, are needed to model these emissions from riparian ecosystems.     

Spatially Disaggregated Inventories of Soil NO and N2O Emissions for Great Britain

Estimates of soil N₂O and NOemissions at regional and country scales arehighly uncertain, because the most widely usedmethodologies are based on few data, they do notinclude all sources and do not account forspatial and seasonal variability. To improveunderstanding of the spatial distribution of soilNO and N₂O emissions we have developedsimple multi-linear regression models based onpublished field studies from temperate climates.The models were applied to create spatialinventories at the 5 km² scale of soil NOand N₂O emissions for Great Britain. The N₂O regression model described soilN₂O emissions as a function of soil N input,soil water content, soil temperature and land useand provided an annual N₂O emission of 128 kt N₂O-N yr^-1. Emission rates largerthan 12 kg N₂O-N ha^-1 yr^-1 werecalculated for the high rainfall grassland areasin the west of Great Britain.Soil NO emissions were calculated using tworegression models, which described NO emissionsas a function of soil N input with and without afunction for the water filled pore space. Thetotal annual emissions from both methods, 66 and7 kt NO-N yr^-1, respectively, span the rangeof previous estimates for Great Britain.     

Emissions of ammonia and greenhouse gases during combined pre-composting and vermicomposting of duck manure

Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH₃), and greenhouse gases (GHG), including nitrous oxide (N₂O), methane (CH₄), and carbon dioxide (CO₂). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH₃ and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH₃ and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N₂O, CH₄, and CO₂ emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg^?1 DM to 274.2, 30.4, and 314.0 mg kg^?1 DM, respectively. Earthworms and amendments significantly decreased N₂O and CH₄ emissions. Emission of CO₂ was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH₃ emission ranged from 3.0 to 8.1 g kg^?1 DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N₂O, CH₄, and NH₃ from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer.     

Nitrous Oxide in Agricultural Drainage Waters Following Field Fertilisation

Dissolved nitrous oxide (N₂O), nitrate (NO₃ ^-), and ammonium (NH₄ ⁺) concentrations in an agricultural field drain were intensively measured over the period of field nitrogen (N) fertilisation and for several weeks thereafter. Supersaturations of dissolved N₂O were observed in field drain waters throughout the study. On entry to an open drainage ditch, concentrations of dissolved N₂O rapidly decreased and a total N₂O-N emission via this pathway of 13.2 g over the period of study (45 days) was calculated. This compared with a predicted emission of the order of 300 g, based on measured losses of NO₃ ^- and NH₄ ⁺ in the field drainage water, and the default IPCC emission factor of 0.01 kg N₂O-N per kg Nentering rivers and estuaries. In contrast to widespread evidence of a clear relationship between the amount of N applied to agricultural land and subsequent direct N₂O emission from the soil surface, the relationship between the amount of N₂O in soil drainage waters and the amount of N applied was poor. We conclude that the complexity, both spatially and temporally, of the processes ultimately responsible for the amount of N₂O in agricultural drainage waters make a straightforward relationship between N₂O concentration and N application rate unlikely in all but the simplest of systems.     

The estimation of N2O emissions from municipal solid waste incineration facilities: The Korea case

The greenhouse gases (GHGs) generated in municipal solid waste (MSW) incineration are carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O). In South Korea case, the total of GHGs from the waste incineration facilities has been increasing at an annual rate 10%. In these view, waste incineration facilities should consider to reduce GHG emissions.This study is designed to estimate the N₂O emission factors from MSW incineration plants, and calculate the N₂O emissions based on these factors. The three MSW incinerators examined in this study were either stoker or both stoker and rotary kiln facilities. The N₂O concentrations from the MSW incinerators were measured using gas chromatography-electron capture detection (GC-ECD) equipment.The average of the N₂O emission factors for the M01 plant, M02 plant, and M03 plant are 71, 75, and 153 g-N₂O/ton-waste, respectively. These results showed a significant difference from the default values of the intergovernmental panel on climate change (IPCC), while approaching those values derived in Japan and Germany. Furthermore, comparing the results of this study to the Korea Energy Economics Institute (KEEI) (2007) data on waste incineration, N₂O emissions from MSW incineration comprised 19% of the total N₂O emissions.     

Fate and distribution of nitrogen in soil and plants irrigated with landfill leachate

Landfill leachate contains a high concentration of ammoniacal substances which can be a potential supply of N for plants. A bioassay was conducted using seeds of Brassica chinensis and Lolium perenne to evaluate the phytotoxicity of the leachate sample. A soil column experiment was then carried out in a greenhouse to study the effect of leachate on plant growth. Two grasses (Paspalum notatum and Vetiver zizanioides) and two trees (Hibiscus tiliaceus and Litsea glutinosa) were irrigated with leachate at the EC50 levels for 12 weeks. Their growth performance and the distribution of N were examined and compared with columns applied with chemical fertilizer. With the exception of P. notatum, plants receiving leachate and fertilizer grew better than those receiving water alone. The growth of L. glutinosa and V. zizanioides with leachate irrigation did not differ significantly from plants treated with fertilizer. Leachate irrigation significantly increased the levels of NH_x-N in soil. Although NO_x-N was below 1 mg N L⁻¹ in the leachate sample, the soil NO_x-N content increased by 9-fold after leachate irrigation, possibly as a result of nitrification. Leachate irrigation at EC50 provided an N input of 1920 kg N ha⁻¹ over the experimental period, during which up to 1050 kg N ha⁻¹ was retained in the soil and biomass, depending on the type of vegetation. The amount of nutrient added seems to exceed beyond the assimilative capability. Practitioners should be aware of the possible consequence of N saturation when deciding the application rate if leachate irrigation is aimed for water reuse.     

Variability of nitrous oxide and carbon dioxide emissions continuously measured in solid waste incinerators

Nitrous oxide and carbon dioxide were continuously measured and variability of emission factors (EFs) was evaluated in five municipal waste incinerators (MWIs) and four industrial waste incinerators (IWIs) from 24 to 86 days between 2008 and 2011. N₂O EFs were calculated by Monte Carlo simulation and mean N₂O EFs were 7.1, 107, 127, 219 g N₂O/ton waste combusted in MWIs with selective catalytic reduction (SCR) for NOx control, MWIs with selective non-catalytic reduction (SNCR), IWIs with SNCR, and a MWI using fluidized bed with SNCR, respectively. Climate-relevant CO₂ EFs ranged from 0.45 to 0.72 ton CO₂/ton waste combusted in MWIs. Maximum values of upper limit for 95% confidence intervals (CIs) of N₂O EFs estimated in each MWIs with SCR, MWIs with SNCR, IWIs with SNCR were 185, 94, 101% of mean N₂O EFs, respectively. Meanwhile, maximum values of upper limit for 95% CIs of CO₂ EFs were much lower as between 18 and 36% in those facilities. 84% CIs of mean N₂O EFs in MWIs with SNCR and IWIs with SNCR were overlapped indicating those values are not significantly different.     

Impact of nitrate-enhanced leachate recirculation on gaseous releases from a landfill bioreactor cell

This study evaluates the impact of nitrate injection on a full scale landfill bioreactor through the monitoring of gaseous releases and particularly N₂O emissions. During several weeks, we monitored gas concentrations in the landfill gas collection system as well as surface gas releases with a series of seven static chambers. These devices were directly connected to a gas chromatograph coupled to a flame ionisation detector and an electron capture detector (GC-FID/ECD) placed directly on the field. Measurements were performed before, during and after recirculation of raw leachate and nitrate-enhanced leachate. Raw leachate recirculation did not have a significant effect on the biogas concentrations (CO₂, CH₄ and N₂O) in the gas extraction network. However, nitrate-enhanced leachate recirculation induced a marked increase of the N₂O concentrations in the gas collected from the recirculation trench (100-fold increase from 0.2 ppm to 23 ppm). In the common gas collection system however, this N₂O increase was no more detectable because of dilution by gas coming from other cells or ambient air intrusion. Surface releases through the temporary cover were characterized by a large spatial and temporal variability. One automated chamber gave limited standard errors over each experimental period for N₂O releases: 8.1 ± 0.16 mg m^?2 d^?1 (n = 384), 4.2 ± 0.14 mg m^?2 d^?1 (n = 132) and 1.9 ± 0.10 mg m^?2 d^?1 (n = 49), during, after raw leachate and nitrate-enhanced leachate recirculation, respectively. No clear correlation between N₂O gaseous surface releases and recirculation events were evidenced. Estimated N₂O fluxes remained in the lower range of what is reported in the literature for landfill covers, even after nitrate injection.     

Effect of fresh green waste and green waste compost on mineral nitrogen, nitrous oxide and carbon dioxide from a Vertisol

Incorporation of organic waste amendments to a horticultural soil, prior to expected risk periods, could immobilise mineral N, ultimately reducing nitrogen (N) losses as nitrous oxide (N₂O) and leaching. Two organic waste amendments were selected, a fresh green waste (FGW) and green waste compost (GWC) as they had suitable biochemical attributes to initiate N immobilisation into the microbial biomass and organic N forms. These characteristics include a high C:N ratio (FGW 44:1, GWC 35:1), low total N (<1%), and high lignin content (>14%). Both products were applied at 3 t C/ha to a high N (plus N fertiliser) or low N (no fertiliser addition) Vertisol soil in PVC columns. Cumulative N₂O production over the 28 day incubation from the control soil was 1.5 mg/N₂O/m², and 11 mg/N₂O/m² from the control + N. The N₂O emission decreased with GWC addition (P < 0.05) for the high N soil, reducing cumulative N₂O emissions by 38% by the conclusion of the incubation. Analysis of mineral N concentrations at 7, 14 and 28 days identified that both FGW and GWC induced microbial immobilisation of N in the first 7 days of incubation regardless of whether the soil environment was initially high or low in N; with the FGW immobilising up to 30% of available N. It is likely that the reduced mineral N due to N immobilisation led to a reduced substrate for N₂O production during the first week of the trial, when soil N₂O emissions peaked. An additional finding was that FGW + N did not decrease cumulative N₂O emissions compared to the control + N, potentially due to the fact that it stimulated microbial respiration resulting in anaerobic micro sites in the soil and ultimately N₂O production via denitrification. Therefore, both materials could be used as post harvest amendments in horticulture to minimise N loss through nitrate-N leaching in the risk periods between crop rotations. The mature GWC has potential to reduce N₂O, an important greenhouse gas.     

Landfill leachate as irrigation water for tree and vegetable crops

The effects of landfill leachate (from Gin Drinker's Bay landfill, Hong Kong) on the growth of tree and vegetable crops were studied in a greenhouse. Higher yields were obtained for Brassica chinensis (Chinese White Cabbage) and B. parachinensis (Flowering Chinese Cabbage) with 5, 10, 20 and 40% leachate dilutions than in the non-leachate control. Yield was reduced for Acacia confusa (Acacia) under all concentrations of leachate treatments. Inhibition of root growth was also observed in the three species with 40% leachate treatment.Leachate-treated soil had elevated levels of electrical conductivity, total-, ammonia) and nitrate-N, exchangeable Na and P. For all heavy metals analysed, only Mn significantly (p < 0.05) accumulated in soil after leachate irrigation.Uptake of N, Na, Fe and Mn was evident for all test species after leachate irrigation. The degree of uptake was positively correlated (p < 0.05) with the leachate concentrations used for irrigation.     

Gas production, composition and emission at a modern disposal site receiving waste with a low-organic content

AV Miljø is a modern waste disposal site receiving non-combustible waste with a low-organic content. The objective of the current project was to determine the gas generation, composition, emission, and oxidation in top covers on selected waste cells as well as the total methane (CH₄) emission from the disposal site. The investigations focused particularly on three waste disposal cells containing shredder waste (cell 1.5.1), mixed industrial waste (cell 2.2.2), and mixed combustible waste (cell 1.3). Laboratory waste incubation experiments as well as gas modeling showed that significant gas generation was occurring in all three cells. Field analysis showed that the gas generated in the cell with mixed combustible waste consisted of mainly CH₄ (70%) and carbon dioxide (CO₂) (29%) whereas the gas generated within the shredder waste, primarily consisted of CH₄ (27%) and nitrogen (N₂) (71%), containing no CO₂. The results indicated that the gas composition in the shredder waste was governed by chemical reactions as well as microbial reactions. CH₄ mass balances from three individual waste cells showed that a significant part (between 15% and 67%) of the CH₄ generated in cell 1.3 and 2.2.2 was emitted through leachate collection wells, as a result of the relatively impermeable covers in place at these two cells preventing vertical migration of the gas. At cell 1.5.1, which is un-covered, the CH₄ emission through the leachate system was low due to the high gas permeability of the shredder waste. Instead the gas was emitted through the waste resulting in some hotspot observations on the shredder surface with higher emission rates. The remaining gas that was not emitted through surfaces or the leachate collection system could potentially be oxidized as the measured oxidation capacity exceeded the potential emission rate. The whole CH₄ emission from the disposal site was found to be 820 ± 202 kg CH₄ d⁻¹. The total emission rate through the leachate collection system at AV Miljø was found to be 211 kg CH₄ d⁻¹. This showed that approximately ¼ of the emitted gas was emitted through the leachate collections system making the leachate collection system an important source controlling the overall gas migration from the site. The emission pathway for the remaining part of the gas was more uncertain, but emission from open cells where waste is being disposed of or being excavated for incineration, or from horizontal leachate drainage pipes placed in permeable gravel layers in the bottom of empty cells was likely.     

Field scale N2O flux measurements from grassland using eddy covariance

In order to assess nitrous oxide (N₂O) emissions from typical intensively managed grassland in northern Britain fluxes were measured by eddy covariance using tuneable diode laser absorption spectroscopy from June 2002 to June 2003 for a total period of 4000 h. With micrometeorological techniques it is possible to obtain a very detailed picture of the fluxes of N₂O at field scale (10³–10⁴ m²), which are valuable for extrapolation to regional scales. In this paper three of the four fertilizer applications were investigated in detail. N₂O emissions did not always show a clear response. Hourly fluxes were very large immediately after the June 2002 nitrogen fertilizer application, peaking at 2.5 mg N₂O–N m^?2 s^?1. Daily fluxes were averaging about 300 ng N₂O m^?2 s^?1 over the 4 days following fertilizer application. The response of N₂O emissions was less evident after the August fertilization, although 2 days after fertilizer application an hourly maximum flux of 554 ng N₂O–N m^?2 s^?1 was registered. For the rest of August the flux was undetectable. The differences between fertilization events can be explained by different environmental conditions, such as soil temperature and rainfall. A fertiliser-induced N₂O emission was not observed after fertilizer application in March 2003, due to lack of rainfall. The total N₂O flux from June 2002 to June 2003 was 5.5 kg N₂O–N ha^?1y^?1, which is 2.8% of the total annual N fertilizer input.     

The release of nitrous oxide from the intertidal zones of two European estuaries in response to increased ammonium and nitrate loading

Nitrous oxide (N₂O) release and denitrification rates were investigated from the intertidal saltmarsh and mudflats of two European river estuaries, the Couesnon in Normandy, France and the Torridge in Devon, UK. Sediment cores and water were collected from each study site and incubated for 72 h in tidal simulation chambers. Gas samples were collected at 6 and 12 h intervals from the chambers during incubation. From these N₂O emission rates were calculated. The greatest rates for both N₂O production and denitrification were measured from saltmarsh cores. These were 1032 μmol N₂O m^?2 day^?1 and 2518 μmol N₂ m^?2 day^?1, respectively, from the Couesnon and 109 μmol N₂O m^?2 day^?1 and 303 μmol N₂ m^?2 day^?1 from the Torridge. A strong positive correlation was apparent with N₂O emission rates and ammonium concentration in the sediment, nitrate concentration in floodwater and sediment aerobicity.     

Effect of commercial mineral-based additives on composting and compost quality

The effectiveness of two commercial additives meant to improve the composting process was studied in a laboratory-scale experiment. Improver A (sulphates and oxides of iron, magnesium, manganese, and zinc mixed with clay) and B (mixture of calcium hydroxide, peroxide, and oxide) were added to source-separated biowaste:peat mixture (1:1, v/v) in proportions recommended by the producers. The composting process (T, emissions of CO₂, NH₃, and CH₄) and the quality of the compost (pH, conductivity, C/N ratio, water-soluble NH₄–N and NO₃–N, water- and NaOH-soluble low-weight carboxylic acids, nutrients, heavy metals and phytotoxicity to Lepidium sarivum) were monitored during one year. Compared with the control, the addition of improver B increased pH by two units, led to an earlier elimination of water-soluble ammonia, an increase in nitrates, a 10-fold increase in concentrations of acetic acid, and shortened phytotoxicity period by half; as negative aspect it led to volatilization of ammonia. The addition of improver A led to a longer thermophilic stage by one week and lower concentrations of low-weight carboxylic acids (both water- and NaOH-extractable) with formic and acetic of similar amounts, however, most of the aspects claimed by the improver’s producer were not confirmed in this trial.     

Anaerobic co-digestion of food waste and landfill leachate in single-phase batch reactors

In order to investigate the effect of raw leachate on anaerobic digestion of food waste, co-digestions of food waste with raw leachate were carried out. A series of single-phase batch mesophilic (35 ± 1 °C) anaerobic digestions were performed at a food waste concentration of 41.8 g VS/L. The results showed that inhibition of biogas production by volatile fatty acids (VFA) occurred without raw leachate addition. A certain amount of raw leachate in the reactors effectively relieved acidic inhibition caused by VFA accumulation, and the system maintained stable with methane yield of 369–466 mL/g VS. Total ammonia nitrogen introduced into the digestion systems with initial 2000–3000 mgNH₄–N/L not only replenished nitrogen for bacterial growth, but also formed a buffer system with VFA to maintain a delicate biochemical balance between the acidogenic and methanogenic microorganisms. UV spectroscopy and fluorescence excitation–emission matrix spectroscopy data showed that food waste was completely degraded.We concluded that using raw leachate for supplement water addition and pH modifier on anaerobic digestion of food waste was effective. An appropriate fraction of leachate could stimulate methanogenic activity and enhance biogas production.     

Extension of EU Emissions Trading Scheme to Other Sectors and Gases: Consequences for Uncertainty of Total Tradable Amount

Emissions trading in the European Union (EU), covering the least uncertain emission sources of greenhouse gas emission inventories (CO₂ from combustion and selected industrial processes in large installations), began in 2005. During the first commitment period of the Kyoto Protocol (2008–2012), the emissions trading between Parties to the Protocol will cover all greenhouse gases (CO₂, CH₄, N₂O, HFCs, PFCs, and SF₆) and sectors (energy, industry, agriculture, waste, and selected land-use activities) included in the Protocol. In this paper, we estimate the uncertainties in different emissions trading schemes based on uncertainties in corresponding inventories. According to the results, uncertainty in emissions from the EU15 and the EU25 included in the first phase of the EU emissions trading scheme (2005–2007) is ±3% (at 95% confidence interval relative to the mean value). If the trading were extended to CH₄ and N₂O, in addition to CO₂, but no new emissions sectors were included, the tradable amount of emissions would increase by only 2% and the uncertainty in the emissions would range from −4 to +8%. Finally, uncertainty in emissions included in emissions trading under the Kyoto Protocol was estimated to vary from −6 to +21%. Inclusion of removals from forest-related activities under the Kyoto Protocol did not notably affect uncertainty, as the volume of these removals is estimated to be small.