The database of GHG Emissions and Removals from Irish Peatlands

This database of GHG Emissions and Removals from Irish Peatlands used in Emission Factor calculations in Aitova et al. (2023) compiles data directly from original published studies, with values presented as reported in those sources. Land Use Categories are following Aitova et al. (2023).

Note: While Helfter et al. (2015), Drewer et al. (2010), Dinsmore et al. (2013) and Levy and Gray (2015) were used to calculate emission factors (EFs) for near-natural peatlands in Aitova et al. (2023), they are not included in this database as they focus on UK peatlands. 

Column headings
Peatland Name: Name used in the study.
Study years: Years that the study was ongoing.
Bog type: Bog type in each publication.
LUC: Land Use Category according to Aitova et al. 2023 (see below).
Drainage status: Peatlands were categorised as rewetted if they had undergone deliberate actions that involved raising and maintaining the water level on the site (be it successfully or unsuccessfully).
Vegetation: Classification according to dominant species and/or Best Practice in Raised Bog restoration in Ireland (Mackin et al. 2017).
MAWT: Mean Annual Water Table in cm. Negative values indicate the water table is below ground, while positive values indicate it is above ground.
Collar N: Number of collars if applicable.
Timeframe: Indicates whether the value represents data for a single year (annual) or an average over the years of study (mean).
FluxType: The categorical value of the measured greenhouse gas (GHG) flux (see descriptions below).
Flux: The numerical value of flux measured as published in the publication.
SE: Standard Error.
Nutrient Status: Peatlands with pH < 5.5 are nutrient-poor; pH values > 5.5 indicate nutrient-rich.
pH level: Numeric value of pH.
TimeSinceRewetting: In years, unless otherwise stated or not applicable.
Peat depth: Reported value or range in metres	
Latitude and Longitude: Location of the study site. 
Method: Closed chamber or Eddy covariance.
GHGAnalyserModel: where available.
Reference(s): The study (ies) from which data were collated.
Link: A direct link to the study. 
Updated: In the case where GHG fluxes from a site were reported in more than one study, only values from the most complete and/or recent study were used in the calculation of EFs in Aitova et al. (2023) to avoid double accounting. For example, Koehler et al. (2011) is used for CH4 and DOC, and McVeigh et al. (2014) is used for CO2 as the most comprehensive study for this gas on the same bog.	


Description of LUC:
Near-natural: In terms of Irish peatlands, near-natural is a more accurate description of unmanaged peatlands as all Irish peatlands have experienced anthropogenic pressure to some extent.
Domestic peat extraction: Extraction of peat with small machinery by private landowners.
Industrial peat extraction: Extraction of peat with heavy milled peat machinery over a large spatial scale. 
Grassland: Grassland on peat soils.	
Forestry: Forestry on peat soils.


Flux Types:
In this database, we followed the sign convention whereby positive values indicate a GHG flux from the peatland to the atmosphere (source) and negative values indicate a flux from the atmosphere to the peatland (sink).
CO2: Carbon dioxide emissions/removals, or Net Ecosystem Exchange (NEE), g C my
CH4: Methane emissions/removals, g C my (g CH4 my in Wilson et al. (2009) were converted to g C my)
DOC: Dissolved Organic Carbon, g C my. When DOC is measured for a site, the value is assigned to the individual habitat.
DIC: Dissolved Inorganic Carbon, g C my. When DIC is measured for a site, the value is assigned to the individual habitat.
POC: Particulate Organic Carbon, g C my. When POC is measured for a site, the value is assigned to the individual habitat.
CO2 evasion: CO2 evasion from the stream surface, g C my. When CO2 evasion is measured for a site, the value is assigned to the individual habitat.
Biomass: Biomass export in grazed grassland, g C my
N2O:  Nitrous oxide emissions, mg N my
Average C balance: CO2, CH4 emissions and fluvial loses combined, g C m y
Full C balance: CO2, CH4 emissions and DOC combined, g C m y
GHG balance: CO2, CH4 and N2O combined and global warming impact calculated, g CO2-eq. m y
NECB: Net Ecosystem Carbon Balance: CO2, CH4 and fluvial combined (and biomass export for grazing grassland category), g C m y
Terrestrial NECB = CO2, CH4eco and CH4live combined, g C m y
GWP: Global Warming Potential, t CO2 eq. ha y, where CH4 = 34 and N2O = 298 (AR5) (g CO2 eq. m y in Renou-Wilson et al. 2016 were converted to t CO2 eq. ha y) 
Emission Factor (EF): A coefficient that quantifies the CO2 emissions/ removals per unit activity (IPCC 2019), t CO2-C ha y 

