FENCES

Project Team

• Professor Laurence Gill gill@tcd.ie
• Morgane Weissenburger - PhD student weissenm@tcd.ie
• Daniel Kaufman - PhD student kaufmada@tcd.ie
• Pétronille Langlais - PhD student langlaip@tcd.ie
• Shane Regan – National Parks & Wildlife Service
• Professor Patrick Morrissey
• Professor Matt Saunders
• Professor Muhammad Ali
• Sate Ahmad – Post Doctorate
• Professor Bidisha Ghosh
• Professor Catherine Coxon
• Professor Stephen Waldren
• Assistant Professor Paul Johnston

 

Location 

Trinity College Dublin, research sites are located nationwide.

 

Theme

 

What is a Wetland?

There are numerous definitions of wetlands, proposed either by government agencies (USEPA, Irish EPA, etc.) or by international organisations (Natura 2000, Ramsar, etc;). The definition proposed by the Ramsar Convention is as follows:

“Wetlands are areas of marsh, fens, peatlands or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres.”

Wetlands are among the most productive ecosystems in the world (de Groot et al., 2012; USEPA, 2018). They provide a sleuth of ecosystem services such as carbon storage, hotspots of biodiversity, water retention, eutrophication prevention, recreation, and ecotourism.

 

What is a peatland?

Peat is the remains of animal and plant constituent accumulating under water saturated conditions leading to incomplete decomposition. This process is driven by anaerobic conditions, limited plant matter decomposability, and a combination of other complex processes (Håkan and Jeglum, 2013).  A peatland is a terrestrial wetland ecosystem where the production of peat exceeds the annual decomposition and thus leads to an accumulation of peat. For an area to be classified as peatland, characteristics such as peat depth and percentage organic matter must be considered. There are efforts to standardize the definition of peatland (Lourenco, 2022).

 

What is a fen?

A fen is a peat forming wetland with a water table near ground level or just below its surface for the majority of the year. Fens are primarily fed by, often base rich, groundwater as well as surface water inputs (Kuczyńska, 2008; USEPA, 2025). Unlike bogs they are not dominated by Sphagnum moss, hosting a rich group of sedges and bryophytes (Ahmad, 2025).

 

Fens can be divided into two major groups based on their hydrological characteristics. Rich fens (also called calcareous fens) are fed by base rich groundwater stored in carbonate bedrock. They are characterized by higher levels of alkalinity and are biodiversity hotspots. In contrast, poor fens are typically more acidic and have more homogenous vegetation communities (Bijkerk et al., 2022; Gill et al., 2022).

 

A small subsection of the Irish peatlands are fens. There are 808 identified fens across the country, with the highest concentrations in the West and Midlands.

 

Distribution of fens in Ireland 2017 – Map made by the IPCC in 2017

 

What is the importance of studying fens?

In Ireland, 20% of land area is peatland (Tanneberger et al., 2017). The vast majority of peatland including fens are degraded and damaged by drainage, peat removal, land use changes, and a host of other anthropogenic activities.

When peat land is damaged it changes from a CO₂ sink and CH_­­4 source to a CO₂ source and CH­­₄ sink (Swenson et al. 2019). Ireland is required to report wetland emissions through the  UNFCCC and the Kyoto Protocol requirements (Duffy et al. 2021).

Fens are one of the most threatened ecosystems in Europe (Bedford, 2003; Gill et al., 2025). Fens, and particularly alkaline or calcareous fens, are included in the Natura 2000 network as a Special Area of Conservation (SAC), listed in the Annex I of habitat of European importance. Fens are also under the RAMSAR convention of wetlands of international importance. Fens provide habitat to critically endangered species. There are over 1000 species that have been recorded in Irish fens, one of the most endangered being the Narrow-mouthed Whorl Snail, included in the Annex II, animal and plant species of community interest of the Natura 2000 European legislation.

 

Narrow-mouthed Whorl Snail (Vertigo angustior) - Global Biodiversity Information Facility (GBIF)

 

Peatlands sites where peat was formally extracted have been rewetted or otherwise restored. We believe many of them will have characteristics similar to fens in the future (Renou-Wilson et al., 2011; NPWS 2019).

 A better conceptual understanding of the hydrologic/hydraulic function of fen wetlands as well as their role in regulating nutrient fluxes and carbon cycling will help to develop a methodology which can be used to investigate and better assess the hydrological and hydrochemical controls that support healthy Irish fen habitats. These insights can be helpful for the development of restoration guidelines which will optimally protect and/or regain the Ecosystem Services from such unique wetlands.

 

Description

The FENCES Project is an interdisciplinary research initiative focused on understanding Ireland’s calcareous fens that provide vital ecosystem services, that is the benefits that nature can provide to humans (IPBES, 2019). Calcareous fens and peatlands in general provide fuel, fibre, food, freshwater, climate and water regulation, erosion protection, biodiversity support, soil formation, nutrient cycling, recreational and educational services (Bonn et al., 2016; Kimmel & Mander, 2010). The FENCES project will focus its research on different sites of calcareous fens from pristine to heavily degraded ecosystems.

The project focuses on developing a deeper scientific understanding of calcareous fen ecohydrology, nutrient cycling, and carbon dynamics across a degradation gradient. The project integrates hydrological, ecological, biogeochemical, field analyses and remote sensing methods to investigate how these systems function under different environmental pressures. By combining field measurements with remote sensing and modelling approaches, the FENCES project aims to build conceptual and empirical models that capture the complexity of fen systems in Ireland. A better understanding of such a complex ecosystem will allow the creation of recommendations for management and restoration measures.

 

Expected Project Impacts 

• Improved quantification of ecosystem services
  • Carbon Budgets
  • Nutrient storage and flows
  • Resilience of the biodiversity to a changing climate
• Improved emissions factors
  • Developing Tier II (nation-specific) and Tier III (more complex, process-based models) emission factors for CO₂, CH₄, N₂O, and fluvial carbon. Guidelines (IPCC 2006) and Wetlands Supplement (IPCC, 2014).
• Restoration recommendations to protect critical habitat

 

Funding Agency

European Protection Agency

 

Participating Organisations

National Park Wildlife Services (NPWS)

 

Specific Policies Covered

Natura 2000, Ramsar Convention, Kyoto Protocol requirements, United Nations Framework Convention on Climate Change (UNFCCC), Water Framework Directive, National Inventory Reports

 

Contact

LinkedIn project page: https://www.linkedin.com/groups/13289288/

ResearchGate profile: 

Bluesky profile: 

Instagram: fences_project