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Background
Ireland’s peatlands, occurring as raised bogs, blanket bogs, or fens, host specialised plant and animal communities, which contribute to global biodiversity and carbon regulation. However, exploitation has reduced the habitat distribution and damaged the ecohydrological functioning of remaining areas.
In the past 100 years, wetland cover has reduced by up to half globally and by up to two-thirds in Western Europe Owen, 2007. As a result, peatlands are now among Europe’s most threatened ecosystems and the conservation and restoration of remaining areas is an international concern.
A peatland system of particular importance is “active”, or peat-forming, raised bogs. These habitats have disappeared almost entirely in temperate climates as a result of land reclamation for agriculture and forestry, fuel production and urbanisation.
Despite these losses, Ireland contains one of the highest concentrations of wetlands in Europe and approximately 60% of the remaining raised bog habitat area in the European Union (EU).
However, mechanised commercial peat extraction, combined with marginal turf cutting, has resulted in the loss of >80% of the original raised bog area. As a result, despite peatland covering over 20% of the Irish landscape, only 9% of the original raised bog area is considered suitable for conservation — and less than 1% is still actively forming peat NPWS, 2017.
Ecosystem Services
Peatlands cover just 3% of the global land surface, yet they are the Earth’s largest natural terrestrial carbon store — holding more carbon than all the world’s forests combined. Their preservation is critical for mitigating climate change.
According to Page and Baird (2016), peatlands store more carbon than any other type of vegetation.
It is estimated that peatlands globally sequester around 0.37 gigatonnes of CO₂ annually Yu et al., 2010, making them essential in the fight against climate change.
Map Layers & Analysis Overview
The PeatSense platform features an interactive map that allows users to explore Ireland’s peatlands by toggling different types of data layers.
- All Ireland Raised Bog Ecotopes: Classified ecotope types, habitat distribution, and emission potential.
- Ecotope Mosaic: Enhanced ecotope classifications including updated patches and additional transitions between ecotope types.
- Slope Layers: Terrain gradient across peatland types, useful for hydrological and restoration planning.
- Irish Peat Soil Map – Soil Types (Gilet et al., 2024):National-scale classification of peat vs. non-peat soils with subtypes such as Raised Bogs, Blanket Bogs, and Fens.
- Sharavogue Hydrology Site: Dipwell and rain data from the Living Bog Project, used for Specific Yield (Sy) analysis of raised bogs.
- Mullingar Met Station: Hourly rainfall data from the Mullingar weather station, used to estimate VWB response in nearby peatlands.
- Emission Factors: Estimated CO₂ emissions or uptake per hectare per year for each ecotope type, based on field studies and scientific literature. The platform calculates carbon impact under three scenarios — Conservative, Average, and Non-conservative — to support restoration and policy decisions.
Together with ecotope classification and soil mapping, slope analysis enhances understanding of peatland conditions and supports evidence-based restoration planning.
Visualizations like pie charts, bar graphs, and histograms are generated based on the selected layers.
Ecological Zones Analysis
When the All Ireland Raised Bog Ecotopes layer is selected, the platform classifies the area using ecological zones called ecotopes.
The following analysis was generated from a user-selected box on the PeatSense map. The ecotope distribution chart below shows the proportion of area covered by each ecotope type (in km²).
Carbon Emission of All Ireland Raised Bog
Based on known emission factors for each ecotope type, the platform estimates the total CO₂ impact.
In this example, the area is dominated by Sub-marginal and Marginal ecotopes — both of which are associated with higher carbon emissions. The presence of these ecotopes can indicate a need for restoration.
Ecotope Mosaic Analysis
The Ecotope Mosaic layer provides enhanced classification of Ireland’s peatlands by integrating updated patch boundaries and transitional zones between ecotope types. This raster-based layer builds upon the original All Ireland Raised Bog Ecotopes by capturing finer-scale ecological variability.
Selected Area Insights
In the example shown below, a selected box area (displayed on the map) has been analyzed using the Mosaic layer. The chart illustrates the proportional coverage (in km²) of each ecotope type.
Carbon Emission Ecotope Mosaic
Based on emission factors for each ecotope, PeatSense estimates the annual CO₂ balance under three scenarios: Conservative, Average, and Non-conservative. The emission factors reflect different assumptions about peatland condition and vegetation productivity.
In this analysis, Sub-marginal and Sub-central ecotopes contribute the most to emissions. The Total emissions estimate varies based on the scenario: negative values indicate net sequestration, while positive values reflect carbon release.
PeatSense uses these factors to estimate the climate impact of selected regions and support science-based restoration planning and policy development.
Further references: For more information about ecotopes see the Ecotope Types section.
Slope Analysis
The Slope Map Layers in PeatSense provide insights into the topographic variation across Ireland’s peatlands. These layers (e.g., Slope Map (based on NLCM) for Raised Bogs, Cutover Bog Slope Map (based on NLCM) for Cutover, and Blanket Bog Slope Map (based on NLCM) for Blanket Bogs) help assess restoration potential, geomorphological conditions, and hydrological dynamics.
Why Slope Matters
Slope plays a key role in peatland formation and degradation. Steeper slopes can lead to surface runoff and erosion, while flatter terrain retains water and supports peat accumulation.
Example: Slope Analysis of a Selected Region
In the example below, a region within the Blanket Bog zone in western Ireland was selected (coordinates approximately: 54.30°N to 53.91°N and –10.03°W to –8.61°W).The Blanket Bog layer was enabled to examine terrain characteristics specific to blanket bogs in the area.
A slope histogram was generated from the raster data, summarizing the area (in km²) for each slope interval class.
The slope analysis shows that the majority of terrain falls within moderate slope classes such as1.00–3.30° (Class D) and 0.50–1.00° (Class C). However, notable portions of the region exhibit steeper gradients above 5.50° (Classes F and G), particularly around the edges. This variety in slope indicates a mix of relatively flat peat accumulation zones and more rugged, erosion-prone areas — a common pattern in blanket bog landscapes.
Why Slope Matters
- Hydrology: Flatter slopes retain water and promote peat accumulation; steeper slopes increase runoff risk.
- Restoration: Low-gradient zones are more favorable for re-wetting; steep areas may need engineering solutions.
- Landscape Assessment: Helps differentiate between intact bogs and cutover/degraded zones.
Volumetric Water Balance (VWB) Analysis
The Volumetric Water Balance (VWB) module in PeatSense enables detailed time series analysis of Water Table Depth (WTD) and Precipitation across fixed dipwell locations. This is used to estimate Specific Yield (Sy)—a critical hydrological property influencing peatland water storage, flow regulation, and carbon balance.
What is Specific Yield (Sy)?
Specific Yield is defined as the amount of water released or stored in a peat profile per unit change in water table depth. It varies depending on depth, peat composition, and geomorphological history. Accurate estimation of Sy helps model water retention and predict peatland response to climate change.
- High Sy: Indicates gradual water table changes and high storage potential.
- Low Sy: Suggests rapid fluctuations and limited storage capacity.
Example: VWB Analysis of a Selected Region
In the example below, a rectangular boundary was selected around the Sharavogue Raised Bog in central Ireland, bounded approximately by coordinates: 53.331°N to 53.344°N and –7.358°W to –7.328°W. This region includes known dipwell locations and allows detailed time series water balance analysis using daily rainfall and dipwell data.
The selected area corresponds to a portion of the Living Bog Project, where long-term dipwell and rain data enabled specific yield estimation using conservative daily methods. This technique provides reliable estimates in areas lacking continuous hourly rainfall data.
Example: VWB Analysis from Sharavogue and Liffey Head
In the example below, WTD and rainfall are plotted for a site at Sharavogue. Specific Yield (Sy = 0.166) was derived using rainfall events and dipwell response. The chart shows seasonal variation in WTD and rainfall over time.
Results from other sites such as Liffey Head showed higher Sy values (up to 0.62), influenced by peat type and restoration status. For instance:
- Sy (Sharavogue, Raised Bog): 0.16 (±0.11)
- Sy (Liffey Head, Blanket Bog): 0.42–0.62 (±0.22)
Methodology Overview
- Identify isolated rainfall events using local Met Éireann daily data.
- Measure water level change in dipwell loggers over 24h periods.
- Calculate Sy as rainfall divided by water level change (adjusted for evapotranspiration where applicable).
This method provides a conservative estimate of Sy using publicly available rainfall data, enabling standardized comparisons across peatland sites. Fixed dipwell locations (from shapefiles) guide the selection of analysis points on the PeatSense map.
Applications of VWB Analysis
- Support restoration planning by identifying sites with low/high water storage capacity.
- Monitor hydrological change post-restoration.
- Quantify resilience of peatlands to climate-driven hydrological shifts.
Ecotope Types and Characteristics
The table below summarizes the biotic and abiotic characteristics of common ecotopes found in Irish peatlands. This classification helps ecologists and land managers assess the condition and restoration needs of different zones. This table was created by Regan et al. (2020), with definitions adapted from Schouten (2002).
| Ecotope | Abiotic Characteristics | Biotic Characteristics |
|---|---|---|
| Facebank | No hummocks and hollows Acrotelm usually absent | Few or no peat-forming plant communities Vegetation dominated by Calluna vulgaris |
| Marginal | No hummocks and hollows Acrotelm usually absent or poorly developed (<0.05 m) | Few or no peat-forming plant communities Vegetation dominated by Calluna vulgaris and Trichophorum cespitosum |
| Sub-marginal | Some differentiation between hummocks and hollows Hollows inundated during small fraction of the year Acrotelm absent or thin (<0.05 m) | Hollows dominated by Narthecium ossifragum and Sphagnum tenellum |
| Sub-central | A micro-topography of hummocks, hollows and lawns, but no pools Lawns are dominant Acrotelm depth variable from 0.10 m to 0.40 m | Lawns dominated by Sphagnum magellanicum |
| Central | A micro-topography of hummocks, hollows and pools Acrotelm moderately to well developed Depth up to 0.5 m | Pools and hollows dominated by Sphagnum cuspidatum |
| Active flush/soak | Wet to extremely wet conditions Pools, hollows, lawns, and large flat hummocks Acrotelm well developed (>0.4 m) | Sphagnum cuspidatum and Sphagnum recurvum lawns with Carex rostrata Myrica gale and Betula pubescens scrub with Sphagnum palustre Molinia caerulea tussocks in some areas |
References
- Owen, P., 2007. LIFE and Europe’s Wetlands: Restoring a Vital Ecosystem. Office for Official Publications of the European Communities, Luxembourg.
- NPWS (National Parks and Wildlife Service), 2017. National Raised Bog Special Areas of Conservation Management Plan 2017–2022. Department of Culture, Heritage and the Gaeltacht, Dublin.
- Page, S. E. & Baird, A.J. (2016). Peatlands and Global Change: Response and Resilience.Annual Review of Environment & Resources. Vol. 41:35-57
- Yu, Z., Beilman, D. W., Frolking, S., MacDonald, G.M., Roulet, N. T., Camill P. & Charman, D. J. (2011). Peatlands and Their Role in the Global Carbon Cycle, . Eos Trans. AGU, 92(12), 97.
- Schouten, M.G., 2002. Conservation and Restoration of Raised Bogs: Geological, Hydrological, and Ecological Studies. The Government Stationery Office, Dublin.
- Gilet, L., Morley, T., Flynn, R. & Connolly, J. (2024). An adaptive mapping framework for the management of peat soils: A new Irish peat soils map. Geoderma. 447, 116933.
- Regan, S., Swenson, M., O'Connor, M. & Gill, L. (2020). Ecohydrology, Greenhouse Gas Dynamics and Restoration Guidelines for Degraded Raised Bogs. EPA Research Report No. 342.