Northern Ireland

This is Northern Ireland. One of the four countries that make up the United Kingdom. Here are some things you might not have known:

Anyway, this interactive app was made during COP26 whilst I was living in Cambridge feeling utterly useless. The idea was to discover more about the "forests" in Northern Ireland.

For the programmers out there, it is all made using OCaml and is open-source.

Forests and Woodland Cover by County

Northern Ireland is made up of six counties. The map now shows the woodland and forest cover per county.

The colours indicate the percentage of woodland cover when compared to total land area per county. Totals are also given. The unit of measurement here is the hectare, for those unfamiliar it is a unit of measurement for area and is equivalent to 10,000 square metres (100m x 100m).

Taken at face value, Fermanagh is quite clearly ahead of the other counties in terms of percentage woodland cover (15.9%) and Armagh the worst (5.5%).

Taking these numbers and averaging them out yields 8.9% forest cover. The EU quotes around 37.7% of its land area being forest. Not necessarily a fair comparison given factors like population density, feasible economic activity (e.g. farming) and habitability. But even compared to a close neighbour like France (~31%) it is really not great.

Another often overlooked dimension to "forest cover" is the type of forest. Ancient woodland (areas wooded since before 1600) is one of the most valuable habitats in the UK. The Woodland Trust conducted a survey aiming to identify ancient and long-established (~1830) woods in Northern Ireland. They found:

Woods that could be classified with any degree of certainty as ancient were many times scarcer in Northern Ireland than in the rest of the UK, covering only 0.04 per cent of Northern Ireland's land area.

A truly sad statistic.

Protecting Forests

Forest management is the study and application of methods aimed at increasing or maintaining the health of a collection of trees. The notion of a forest is already hard to define (anyone who has read Colin Tudge's "The Secret Life of Trees" knows how hard it is to even define a tree), the health of a forest is even harder.

A clear distinction is given between afforestation (planting trees on land not previously forested) and reforestation (planting trees on land already considered forest). The latter does not count as increasing the amount of forest, which could be problematic when policies require "more forest". There's a tendency to lean towards afforestation through monoculture plantations. J. Ruby Harris-Gavin puts it bluntly for Ireland's Department of Agriculture, Food, and the Marine (DAFM).

... DAFM are technically creating new forests based on their own respective definitions, they are actually cultivating monoculture tree plantations of single species - moreover, they are doing so in areas with trees planted too close together for any wildlife or other plant life to survive

At a superficial level a mantra of "the more trees the better" sounds good, indeed many so-called carbon-offsetting companies would have you believe this. But density alone is not necessarily a good indication of health. We can fit younger trees more compactly in a given space to augment our density score so should we chop down all of the old, large trees? Another incredibly important metric neatly side-stepped here is biodiversity. This is evident in the monoculture plantations mentioned above. Research has already pointed to the devastating impact this can have, Veldman et al. show the alarming effect it can have in grassy biomes.

Forests have economic value and wood is just one of the commodities available from forests and plays an important role in how the forest is managed. Forests provide a means for regenerative resources to fuel a more sustainable economy. But left unprotected, the tragedy of the commons tells us exactly how forests mined for the economic potential will end up. Policy, education and local community engagement can go a long way in preventing this.

In truth, there is no well-defined single answer to how healthy a forest is. It is a combination of all of these factors (and more) with different priorities weighting each depending on which stakeholder group you find yourself in. Turning a blind-eye to other stakeholders will not lead to any productive, long-term solutions. This short section was somewhat inspired by John D. Castello's and Stephen A. Teale's "Forest Health: An Integrated Perspective" in which they argue for an objective, scientific method based on mortality rates and I'll leave you with a quote towards the end of the book:

The problems facing the world's forests are immense and they will not be solved any time soon. However if forest health professionals, scientists and policy makers cannot come to a consensus on what a healthy forest is, then there is little hope that the processes the reduce and degrade a forests can be objectively assessed...

As far as I can tell there's no getting around the importance of local, community knowledge. Methods we use in the future should probably recognise this and preserve as much of it as possible.

New Trees in the Belfast Hills

After protecting existing trees and rewilding as much as possible through natural regeneration, there's still a need to plant trees. For the potential of rewilding look no further than Eoghan Daltun's incredible work in the South of Ireland in the Beara Rainforest is amazing.

Not only that, but we need:

For large-scale reforestation projects, engagement of multiple stakeholders is required, to meet the diverse goals of enhancing rural livelihoods, biodiversity conservation, carbon sequestration, watershed protection and the provision of other ecosystem services

In fact their paper is well worth a read. Their comments on "Making it pay" are not very in-depth but overall I think it is a useful read.

The map has zoomed to near Cavehill and Belfast Zoo where the Woodland Trust are planning on planting some 150,000 trees for a new Glas-na-Bradan Wood. As far as I can tell this is an example of afforestation (I couldn't find any information saying it previously was woodland) done correctly.

Access to green space is incredibly important, the pandemic has exacerbated this for many. The NHS Forest project is evidence of this:

The NHS Forest works with healthcare professionals and organisations to make green spaces available for health purposes. We carry out practical work on the empirical links between health and the environment.

Carbon beneath your feet

When discussing terrestrial carbon sinks most people would think of forests with trees and shrubs. For many people in Ireland (and other parts of the UK such as the Fens in eastern England) another important carbon sink they will be familiar with is peatland. In fact only Canada, Finland and Indonesia have more peatland as a percentage of land cover than the island of Ireland.

Peatland is characterised by its waterlogged ecosystem and is a type of wetland. Peat itself (sometimes called turf) is partially decayed vegetation. There are many types of peatland from the temperate, blanket mires here in the UK to the tropical, peat swamps of Southeast Asia. Estimates indicate that 3% of the Earth's surface is made up of peatland.

Incredibly peatlands store and sequester more carbon than any other type of terrestrial ecosystem.

Please note, the peatland displayed on the map is both old data (1980s) and has been simplified with the excellent mapshaper to help reduce the size of the data to make the map a little more responsive (although you may have to use the keyboard to move about). A more up to date approach might be to use the Peatland Monitoring from Space data.

Identifying and tracking peatland through satellite imagery is challenging but a worthwhile pursuit. As Prof. Kevin Tansey for the MDPI special issue on the "Remote Sensing of Peatlands" put it:

... Satellite data can be used to establish the extent of peatlands, their elevation and topographic characteristics, the land use/land cover change history, the diversity of the vegetation, the fire disturbance impacts and various measurements associated with the atmosphere, such as emissions, smoke and air quality.

There are some interesting papers in that special issue, in particular Rahman et al.'s "A New Method to Map Groundwater Table in Peatlands Using Unmanned Aerial Vehicles" is very cool! The author's describe a technique of interpolating known groundwater level (GWL) measurements to estimate the GWL across the peatland. The known measurements are from areas of surface water which are captured using a UAV. They used ENVI to extract the open water sections from the images.

Peatland can provide other important natural processes as well as acting as a carbon sink. In Co. Tyrone peatland restoration is providing cleaner drinking water by acting as a filtration system before water from Lough Bradan reaches the water treatment facility. This makes the job of treating the water less intensive using fewer chemicals and less electricity in the process. BBC NI covered it just recently.

Northern Ireland does have a peatland restoration and protection plan, their consultation document is available online. They note some of the worrying trends that put our peatland at serious threat:

... Since the early 1980s there has been a trend towards mechanised peat extraction, which has greatly accelerated bog degradation and loss... On bogs, inappropriate levels of grazing and trampling from grazing livestock can have adverse effects on the peatland ecosystem...

But the amount of protection seems woefully low

The best areas of semi-natural peatland habitats in Northern Ireland are designated and protected under National, European and International nature conservation legislation to afford them the greatest protection. However, site designation only covers around 10% of seminatural peatland habitat in Northern Ireland.

Their objectives and strategies are heading in the right direction, but given the emergency of the climate crisis are worded a little vaguely and cautiously (but perhaps that's just politics).

  1. Encourage the reduction and cessation of the use of peat by all statutory bodies and agencies by end of 2022.
  2. Seek to phase out the use, import and sale of peat compost in Northern Ireland by 2025.
  3. Conduct a review on the potential for a ban on peat extraction on all publicly owned land by 2022.

Whilst writing this section, the National Trust joined others in calling for a ban on peat products. Peat is commonly used as compost and in particular for the new trees used in reforestation efforts. This is a good step in the right direction, but the slowness of the response is worrying.

Forests in the sea

For a completely different notion of forest, we can look beneath the waves. Seagrasses are the only flowering plant able to live in seawater. Seagrass forms meadows typically in shallower waters just off the coast. According to Project Seagrass and other sources:

Seagrasses occupy 0.1% of the seafloor, yet are responsible for 11% of the organic carbon buried in the ocean.

The data plotted from OpenDataNI shows subtidal and intertidal seagrass beds in Strangford Lough (a Marine Conservation Zone and the British Isles' largest inlet).

During the writing of this section, the Environment Agency released a handbook for the restoration of seagrass. Strangford Lough gets a special, small mention:

Patches of seagrass may also occur within pebble and rubble environments (e.g. Strangford Lough in Northern Ireland), near other sensitive sedimentary habitats such as oyster reefs, maerl beds and mussel beds, and within other coastal habitats such as saltmarsh and mudflats.

Unfortunately, Green et al. have brought to light just how catastrophically the seagrass loss in the UK has been.

... at least 44% of United Kingdom's seagrasses have been lost since 1936, 39% since the 1980's. However, losses over longer time spans may be as high as 92%.

The good folk at Project Seagrass are working hard to raise awareness for the disappearing meadows. Recently, they announced their first Seagrass nursery. The OpenDataNI information seems to suggest more work will be planned to complete mapping in Northern Ireland in particular for Larne Lough and Carlingford Lough.


This was a fun, small project I did during COP26. Nothing revolutionary or new, but maybe you learnt something or were inspired by some of the interesting projects highlighted. If there were any takeaways to be had I think they would be.

If there are any mistakes or suggestions feel free to contribute directly or with issues. You can also find me on twitter.

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