Making space for natural processes: forest to bog restoration at RSPB Forsinard Flows Reserve

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1 Climate change adaptation case study #2 Making space for natural processes: forest to bog restoration at RSPB Forsinard Flows Reserve This case study demonstrates SNH s third climate change adaptation principle: the importance of making space for, and restoring natural processes, allowing ecosystems to increase resilience against climate change pressures. Designated as a nature reserve in 1995, Forsinard Flows is located in Caithness and Sutherland in the north of Scotland. Here you can find a vast area of blanket bog - Europe's largest - known as the Flow Country. However, in the 1970s and 1980s, large areas were chosen as sites for non-native conifer plantations, affecting the hydrological (water regulating) function of the bog, and contributing to losses of habitats and wetland species. Blanket bog ecosystems are at risk from climate change as they are vulnerable to changes in rainfall and temperature. Healthy active bogs are more resilient to climate change, however, and adaptation focuses on restoring the natural functions of degraded bogs. The RSPB bought the reserve in 1995, and since then, their work to fell the trees and restore the bog hopes to improve climate change resilience by, in time, returning the bog to a healthy state. Restoration also has the benefits of carbon storage for climate change mitigation, and once again creating a good habitat for wetland species. Figure 1: The Flow Country is famous for its wide open landscapes and myriads of bog pools. (Lorne Gill/SNH) 1

2 1. The climate change risk: blanket bogs and hydrology Blanket bog: a unique habitat Peat bogs are unique and spectacular landscapes. They are habitats for many rare birds and other species; the peat preserves a detailed record of past vegetation, climates and human activity, going back thousands of years; they capture and store atmospheric carbon in their natural state, contributing to regulating the Earth's climate; and finally, they are also important for local communities, helping support tourism, agriculture and field sports. Blanket bogs rely on regular rainfall, and cool summers, conditions often found in Scotland. They consist of two layers; the uppermost is an active living surface of peat-forming vegetation such as Sphagnum mosses which help create permanently waterlogged conditions. Sphagnum mosses blanket the ground, and, due to the cool, acid and waterlogged conditions, they do not fully decompose, leading to the build-up of peat soil, which is made up of remains of mosses and other bog plants accumulated over 1000s of years. This makes up the lower layer, which can have a depth of up to 10 metres. Hydrology is very important to this ecosystem. If a bog s hydrology is affected for example, if the water table is lowered and the surface is dried out the Sphagnum mosses and other bog plants can no longer survive. The surface layer begins to degrade, releasing potentially large quantities of stored carbon back into the atmosphere, contributing to climatic warming (IUCN, 2014a). Figure 2: Sphagnum moss at The Flows National Nature Reserve (Lorne Gill/SNH/2020Vision) Forested bogs The RSPB Forsinard Flows houses a portion of the vast area of blanket bog located in Caithness and Sutherland in the north of Scotland. Almost 5% of the world s blanket bog is to be found here, and it is a habitat of international importance. Much of the RSPB site is also a National Nature Reserve, (NNR). After 1945, forestry on peatlands was promoted by the government through grants and tax concessions. In the Flow Country, large areas were planted with non-native conifers in the 1970s and 1980s, despite having been treeless for thousands of years, radically altering and degrading the bog and its wildlife. In order for forests to grow on peatlands, the ground needs to be ploughed to a depth of a metre or more, and drained dramatically affecting water table, bog vegetation, and animals. Growing trees disturb the hydrology, as the roots extend into the peat (RSPB, 2011). Moreover, water is lost by the trees through evapotranspiration 2

3 Figure 3 (above): Map showing the Flow Country, including The Flows National Nature Reserve (green) and the Caithness and Sutherland Peatlands Special Area of Conservation (blue). Figure 4: (right) Map showing RSPB Forsinard Flows reserve evaporation and transpiration and the tree canopy intercepts rainfall, reducing the amount of water that reaches the bog by up to 40% (IUCN, 2014b). As a result of this and deep shading, the bog vegetation is eventually completely destroyed. Loss of Sphagnum mosses and the generally drier conditions leads to the bog degrading, ceasing to lay down new layers of peat, and is no longer an active peat-forming bog. The carbon store that has accumulated over millennia begins to be released into the atmosphere, and the bog turns from a carbon sink, where carbon is taken out of the atmosphere, to a carbon source, where it is being released into the atmosphere. Facing climate change: active bogs Peatlands are sensitive to anticipated climate change. Temperature rise leads to the peat drying out in summer, and an increased risk of moorland fires, while heavier rainfall may cause more erosion on those peatlands that are already damaged or degraded (Marsden & Ebmeier, 2012). Bogs are quite resilient habitats, having sustained climatic variations for the last 10,000 years. However, they are only able to remain intact in the face of change if they are healthy, meaning that they are in an active, peat-forming state (IUCN, 2014c). This is not the case when they have been exposed to land use changes such as afforestation. The IUCN note that: recent surveys have identified that more than 80% of UK peat bogs now lack such an active living surface as a result of human impacts, and that they therefore have little or no capacity for resilience in the face of climate change (IUCN, 2014c). Not only are afforested peat bogs less able to cope with climate change, but when there is no longer a living surface layer as a result of draining and limited water supply, in their degraded state they are also releasing carbon into the atmosphere, contributing to climatic warming. 3

4 2. Adaptation Principle: Making space for natural processes In order for blanket bogs to become more resilient to the negative impacts of man-made climate change it is important to restore their natural processes to ensure that they remain peat-forming. This is a key priority. The National Peatland Plan states that the vision for 2020 is for Scottish peatlands to be improving, and for those in protected sites to be in good condition (SNH, 2015). The Forestry Commission has also revised its policies since the 1980s; it is no longer permitted to establish new woodland on deep peat (over half a metre). Adaptation for blanket bog includes restoring the water table and hydrological functioning. Since purchasing the reserve in the mid-1990s, the RSPB has worked to restore natural processes and bog habitats on afforested areas at the Forsinard Flows by felling the trees, restoring the water table, controlling tree regeneration and managing deer grazing. In 2001, along with SNH, the Forestry Commission Scotland, and Plantlife, the RSPB was the recipient of a 2.8 million European Union LIFE Nature grant to restore the bog. Trees have been felled over the course of many years, and then crushed into the plough furrows, recreating the open landscape. Two phases have been completed over the course of a decade: first trees were felled to waste, then drains were blocked, and in the second phase brash cutting and furrow damming helped to raise the water table further. The creation of peat dams and blocking drains raises the water table, rewetting the bog and allowing for the growth of peat-forming vegetation. This vegetation then smothers the dead trees, and preserves some of the carbon in the wood. The return of peat-forming vegetation such as Sphagnum mosses and bog cotton restores the habitats for wetland wildlife (RSPB, 2015). Figure 4: Pre-crushing and damming of forestry plantation, as part of peatland restoration at RSPB Forsinard Flows Reserve. (G. Thompson/RSPB, February 2015). Figure 5: Brash cutting and furrow damming under way at RSPB Forsinard Flows Reserve. (G. Thompson/RSPB, February 2015) 4

5 3. Results This is one of the largest peatland restoration projects in the UK (RSPB, 2011). At the sites where the earliest work was done in 1998, there has been significant recovery. The trees on this site were less mature than those felled today, which have had an extra seventeen years to grow. There was therefore still some bog vegetation left here, allowing for a faster recovery. Though the plough furrows and ridges from the plantation remain, the site is returning to a healthy blanket bog state. The furrows which contributed to exposing and oxidising the peat, are now filling up with mosses and peatland plants, recreating the former vegetation mix found on the blanket bog, and contributing to restoring its natural processes of capturing carbon from the atmosphere, and storing it in the peat soil (RSPB, 2011). Figure 6: Bog cotton growing at Talaheel, one of the earliest restoration areas on RSPB Forsinard Flows Reserve. (Mark Hancock/RSPB) RSPB's Forsinard Flows Reserve has also become a centre for research on carbon, bog hydrology and ecology in partnership with major universities and research institutes, including the Environmental Research Institute (part of the University of the Highlands and Islands), based locally at Thurso. This research is contributing to our understanding of how draining and disrupting the hydrology affects carbon fluxes (RSPB, 2011). However, there is still plenty of work to be done: more trees will be felled where inappropriate forestry remains on deep peat soils, and further drains need to be blocked (RSPB, 2011). It is the ambition that this will lead to a vibrant ecological community, and a healthy blanket bog, which will help restore the Flow Country. Overall, it is important to recognise that the restoration process for peatlands is slow but steady, reflecting the pace of the peatland s natural processes. Where funding is available, more intensive 5

6 measures, like additional dams on drainage furrows, can help nature speed up the return to a healthy state. For the work that is carried out now on more mature plantation sites, there is both the initial process of felling and blocking drains, as well as removing timber and crushing it into the plough furrows (see Figures 4 and 5). Follow-up management involves furrow-blocking, and removing the plough ridges by machines crushing old stumps to restore the original flat topography. This second stage helps to raise the water table more quickly. Figure 7: after initial felling in , restoration enhancement work in 2012 involved brash crushing and blocking furrows with peat dams (Andy Skinner/RSPB) Research and management trials are also being carried out to improve restoration techniques. These have responded to the challenge of carrying out restoration on these more mature sites. Here, trees can be 6-8 metres high, and also have some commercial value for biomass and timber. Increasingly, trees are being completely removed from the site, rather than left to decompose, and more and less intensive techniques for both tree removal and drain blocking are being trialled, in order to have the best-possible knowledge to continue with the restoration. 6

7 4. Wider benefits As mentioned, healthy, peat-forming blanket bogs are not only more resilient to changes in climate, but they also contribute to mitigating climate change by storing carbon. Climate change mitigation is also a policy driver for peatland restoration in the Scottish Government as carbon is captured and stored in peatlands, making restoration increasingly important (Marsden & Ebmeier, 2012). Moreover, peatland restoration contributes to re-establishing rarer wetland habitats for birds and other species. Afforestation displaces blanket bog birds, and some species are negatively affected within about 800 metres of the forest s edge (RSPB, 2011). These species are the replaced by woodland birds, which are more common at a national level, than the characteristic wetland birds of the blanket bogs (Stroud et al., 1988). However, since restoration began, species such as golden plover, dunlin and greenshank have started to return for formerly forested areas in the Flows (RSPB, 2011). Figure 8: Golden plover is one of the most characteristic wading birds of the Flow Country (Lorne Gill/SNH) We hope that the restoration of the bogs at Forsinard Flows will contribute to creating a vibrant natural landscape which provides homes for several of our most important bird species, and an outstanding natural area for visitors. 4,000 visitors come to Forsinard Flows every year, and this contributes 190,000 to the local economy (RSPB, 2011). In addition to the estimated 10.5 million total project expenditure over 5 years, the current Flows to the Future project is expected to deliver a further 6.3 million of benefit (Gross Value Added) across Caithness and Sutherland in the next 30 years. Healthy bogs will also become increasingly important to ensure that more carbon is not lost into the atmosphere, helping regulate the Earth's climate for the benefit of all, and to ensure the survival of these important habitats for future generations. 7

8 REFERENCES AND FURTHER READING FC (2000). Forests and Peatland Habitats. Forestry Commission report, July, Online. Available from: [Accessed: 12/05/2015]. FC (2015). Deciding future management options for afforested deep peatland. Forestry Commission Practice Guide, Online. Available from: [Accessed: 20/07/2015]. Gallego-Sala, A.V., Clark, J.M., House, J.I, Orr, H.G., Prentice, I.C., Smith, P., Farewell, T., Chapman, S J. (2010). Bioclimatic envelope model of climate change impacts on blanket peatland distribution in Great Britain. Climate Research. 45: Online. Available from: [Accessed: 02/06/2015]. IUCN (2014a). Peat Bog Ecosystems: Structure, Form, State and Condition. IUCN UK Committee Peatland Program, Briefing Note N o 2. Online. Available from: [Accessed: 28/05/2015]. IUCN (2014b). Ecological Impacts of Forestry on Peatlands. IUCN UK Committee Peatland Program, Briefing Note N o 4. Online. Available from: [Accessed: 28/05/2015]. IUCN (2014c). Peat Bogs, Climate and Climate Change. IUCN UK Committee Peatland Program, Briefing Note N o10. Online. Available from: [Accessed: 28/05/2015]. Marsden, K., & Ebmeier, S. (2012). Peatlands and Climate Change. SPICe Briefing, Scottish Parliament Information Centre. 20 April, Online. Available from: ResearchBriefingsAndFactsheets/S4/SB_12-28.pdf [Accessed: 02/06/2015]. Natural England (2014). Climate Change Adaptation Manual. Natural England, 3 June, Online. Available from: [Accessed: 12/05/2015]. RSPB (2010). Scotland s Land-Use Future. Royal Society for the Protection of Birds, report. Online. Available from: [Accessed: 01/06/2015]. RSPB (2011). Bringing life back to the bogs. Royal Society for the Protection of Birds, report. Online. Available from: [Accessed: 10/06/2015]. RSPB (2015). Forsinard Flows Peatland Restoration Green stimulus peatland restoration report to SNH. SNH (2015). Scotland s National Peatland Plan. Scottish Natural Heritage. Webpage. Online. Available from: [Accessed: 27/05/2015]. Stroud, D.A., Reed, T.M., Pienkowski, M.W., Lindsay, R.A., (1988). Effects of afforestation on the ecosystem. In: Bogs, birds and forestry: The peatlands of Caithness and Sutherland. D.A. Ratcliffe and P.H. Oswald, eds. Nature Conservancy Council. Online. Available from: [Accessed: 02/06/2015]. SNH, 2015 For more information on the Forsinard Flows and its management please visit This publication is part of a series of case studies on the climate change adaptation principles. For more information on the principles, and how SNH is helping nature adapt to climate change, please contact Julia Quin julia.quin@snh.gov,uk or Anna Brand anna.brand@snh.gov.uk or visit