Peatland restoration - a path more often travelled
- Thursday, 11 June 2015
Bog - wet, easy to sink into, need to wear your wellies, and off the beaten track...
A bog is a wetland made up of a range of wetland plants and mosses, including several species of Sphagnum Moss. Sphagnum moss thrives in constantly wet conditions. Raised blogs began forming 7,000 to 8,000 years ago, and blanket bogs over the last 2,000 years. These bogs have a wide range of benefits including providing a home for animals, storing carbon, adding to the landscape, and helping to regulate water flows and reduce flooding downstream.
What's all this got to do with forestry? We take a holistic approach to managing the landscape and we work to protect and in some cases, restore many of the benefits that various land uses provide.
In 2014 we secured funding of £1.6m from the Peatland Action fund which is run by Scottish Natural Heritage, with the aim of sequestering and storing carbon through the restoration of peatland.
We tackled 24 different sites across Scotland, all involving either blanket bogs or lowland raised bogs.
The work aimed to restore the particular growing conditions required by the type of vegetation found only on bogs. This included removing trees (which cast shade and replace the valuable plants), and drain blocking which is very important to re-wet the peat to make it very wet at the surface. A large part of the restoration was carried out by staff from our North Highland office, which complements the work of the Peatlands Partnership across the whole of the Flow Country. Other sites were in Tay, Galloway, West Argyll, and Scottish Lowlands.
A closer look at bog restoration in West Lussa, mid Kintyre
West Lussa sits on the crest of one of the rounded hill tops characteristic of mid Kintyre. Many of the other hill tops within the forest were left open during the intensive planting phase of the late 1960's and 1970's but this site was ploughed and planted with sitka spruce, leaving only a small area of intact blanket bog nearby. The blanket bogs here are unusual in there positioning on the tops of the hills. This is due to the local terrain, with the relatively flat tops holding rainwater for long enough to allow peat to form, whereas away from the tops, the slope and natural drainage increases preventing peat formation.The peat deposits are locally important refuges of native flora above the intensively managed agricultural ground along the coastlines and the forestry on the hill slopes. The carbon stores in the peat on the 5, now 6, open hill tops in Lussa forest collectively are significant and worthy of protecting for the future.
The area is largely covered by 40yr old sitka spruce which has grown very slowly under the waterlogged conditions. Small patches of bog vegetation survived in the wettest, unplanted parts with wet heath covering much of the rest of the site in the rides and under the conifer canopy.
The aim of the restoration work was to restore the original hydrology conditions of the deep peat, and to connect the site to bog/wet heath immediately adjacent to the PAF site, and to prevent further drying of the hill tops hydrological unit.
The trees growing on the bog were manually felled by chainsaw and branches were removed to reduce their volume. The pruned material was packed into the plough furrows to slow down the movement of water across and out of the site along these features.
Subsequently, an 8 ton excavator with 1000mm tracks was brought in to block the drains with peat dams.
Parts of the site had trees large enough to make harvesting or mulching machinery the best option for tackling them, whereas others had tiny stunted trees. However, the presence of very wet natural or modified seepage channels crossing the site further added to the challenges of introducing heavy machinery onto the site.
To get round these issues, experienced operators used chainsaws which meant that we didn't have to use machines which could have got bogged or cutting up the peat surface.
Removing the conifers can prevent the site drying out and releasing its stored carbon; re-wetting enables bog vegetation to recolonise and begin taking in carbon from the atmosphere once more.
This helps reduce the overall net amount of carbon dioxide being released into the atmosphere by using fossil fuels across Scotland. At a more local level, it is hoped that the bog will act to increase biodiversity by increasing the availability of open habitats within the forest.
This will benefit woodland edge species such as black grouse and true open habitat and bog species such as snipe, many of which have been using the site already over the winter period. The site also has an abundance of heathland and bog specialist berry species such as blaeberry, crowberry, cow berry and cranberry.
Andrew McBride, Peat Manager for SNH, said: "The short turnaround of the Peatland Action Project has been a real challenge to us all, but FES staff and contractors really showed their metal, battling against storm force winds and snow to deliver good quality peatland restoration on time and on budget. Through Peatland Action we have shown how two government organisations can find common ground to get action on the ground to benefit biodiversity.”
Why is restoring the conditions of bogs so important?
Other than carbon storage, bogs have a variety of roles and benefits including:
- biodiversity: peatlands provide a habitat for animals and plants;
- water: peatlands improve water quality and can in some cases, help reduce the instances of flooding downstream;
- recreation and working landscapes: peatland makes up some of our most scenic landscape like the Flow Country, which is a popular area for hill walking and leisure activities. Many peatland areas are used for farming; and
- cultural heritage: the remains of our past can be found in the bogs and can be studied.
Did you know?
- blanket bog is reckoned to cover at least one million hectares of land in Scotland
- peatlands are found in at least 175 countries and cover around 4 million km2 or 3% of the world's land area.
- the UK is amongst the top ten nations of the world in terms of its total peatland area;
- the UK has between 9 -15% of Europe's peatland area (46,000 -77,000 km2) and about 13% of the world's blanket bog – one of the world's rarest habitats;
- peat soils in Scotland contain almost 25 times as much carbon as all other plant life in the UK. The carbon stored in Scotland's soils (notably peat and peaty soil) is equivalent to over 180 years of greenhouse gas emissions from Scotland at current emission rates.
- the Flow Country of Caithness and Sutherland is part of a vast expanse of blanket bog. It is widely recognised as the largest expanse of blanket bog in Europe. Blanket bog habitat covers approximately 400,000 hectares, 50% of the total area of Caithness and Sutherland; and
- underneath the living peatland surface of The Flow Country is an estimated 400 million tonnes of carbon. That's more than twice the amount found in all of Britain's forests combined. The carbon stored in Scotland's soils (notably its peat and peaty soils) is equivalent to over 180 years of greenhouse gas emissions from Scotland at current emission rates.
Sources: The Peatlands Partnership and Habitat Action Plan for Blanket Bog JNCC.