I started volunteering with the RSPB at Dove Stone reserve last January, adopting an internship in July. I have been helping to restore blanket bog habitat through harvesting/planting sphagnum moss, gully blocking and creating fire breaks by clearing heather. Project officer Gareth Roberts and I thought it a good idea for me to blog about my experience as a volunteer and the work being carried out. We both feel, along with other areas of conservation that this type of work is often overlooked by the public. You can find Gareth’s blog posts here.
The importance of blanket bogs
Before I heard about this project I’d been studying the ecosystems of wetlands and their role in carbon sequestration (storing carbon) at university. It was a surprise to me just how important these ecosystems are at mitigating the effects of human activity, so when I learned that approximately 80% of our bogs are in poor condition and saw this volunteer opportunity, I jumped on the chance to get involved.
Of course like most ecosystems, bogs provide other services which benefit us in ways you may not expect. One of their most important services which benefits us directly is water storage and regulation. You may remember the floods late last year (2015), well blanket bogs can help retain and store much of the water from heavy rainfall that would otherwise flow down from upland areas into rivers leading to local villages and towns. It is widely believed that restoring the uplands ability to store water and slow down the flow, will have the potential to alleviate, even prevent the severe socio-economic consequences of floods. In contrast to heavy rainfall, in summer months where rainfall is significantly less, the stored water could also provide a slow outflow into rivers and streams preventing them from drying up.
Blanket bogs also play a role in cleaning this stored water by breaking down and filtering contaminants harmful to our health, making them an asset to utility companies who use upland surface waters as drinking water reserves. Conditions of these bogs have worsened over time from atmospheric deposition (air pollution) and management practices such as as burning and overgrazing which removes key vegetation and exposes bare peat. This has resulted in utility companies having to remove increasing amounts of dissolved organic carbon inputs from water. This process adds significant costs to water bills, whereas a healthier bog ecosystem will reduce these processing costs.
As mentioned, bogs are incredibly efficient at storing carbon due to peat forming plants such as mosses (sphagnum), including some sedges and shrubs. These plants remove CO2 from the atmosphere through the process of photosynthesis, using sunlight and CO2 to create oxygen and carbohydrates used to develop tissue. As they die, because the environment is waterlogged and acidic, the rate of decay is inhibited significantly. This means the plant material which stores carbon will begin to accumulate as it doesn’t break down well and will start to form peat, storing it for hundreds to thousands of years. The accumulation of carbon through this process tends to be a lot faster than it is lost and this is of great importance, especially when you consider the extent of CO2 being released from fossil fuel emissions.
It is estimated that over 138 megatonnes of carbon are stored in blanket bog/upland valley mires and up to 584.4 megatonnes in all deep and shallow peaty soils, Natural England (2014). As bogs begin to degrade they begin to release this stored carbon having the potential to emit vast amounts of CO2. On top of CO2 emissions, methane and other greenhouse gases are released into the atmosphere contributing to the potential worsening of air pollution and climate change.
Habitat to wildlife
In keeping with giving nature a home, bogs offer a unique habitat to even more unique species of mammal such as mountain hare, water voles and nesting species of bird such as curlew, dunlin and golden plover, not to mention insects key to their diet. As bogs are relatively species poor, this makes their preservation even more imperative given the scale of potential degradation.
Now that you’ve learned a little about why these now, delicate ecosystems are important, I invite you to learn about the voluntary work I’m getting involved with and stories from the bogs!
Harvesting and replanting Sphagnum moss
As you now know, sphagnum moss is a keystone species in the creation of bog habitat and its reintroduction has been one of the more significant tasks of the project. The objective has been to plant over 150, 000 individual handfuls across 40 hectares of the reserve.
Part of my role has been to conduct surveys across the reserve using a GPS, to find established sphagnum moss communities that we’re able to harvest from. A perfect community would be one larger than 1 m² with others located around it. This makes it easier for us when we’re harvesting as we collect 25 individual handfuls of moss per bag and can take no more than 10% from each 1 m² patch.
Once we’ve harvested a couple of bags each, careful not to stand on any existing replanted areas, we look for suitable places to plant. Typical areas are often surrounded by cotton grass and are a good indicator as they prefer to grow in waterlogged conditions. Using a fork handle as a borer, depending on the sphagnum size, we create a hole and gently place the moss in it, squeezing the peat around it to secure it in place. Each handful is spaced roughly 1 m apart and the planted area is marked out using a GPS track and stakes to measure our progress.
Raising the water table is not only a way to reduce the effects of wind erosion, it aids in creating habitat for vegetation like peat mosses and wading birds such as curlew. One method of raising the water table is blocking gully’s that form naturally as water flows down higher regions of a raised bog. Part of my work was to survey gully’s suitable for a series of dams with the aim to essentially flood the surrounding area.
Unlike the existing 100 stone dams that have been installed, these blocks were developed using interlocking corrugated plastic piling. The piling was delivered via helicopter at drop points which me and the other RSPB staff helped direct on the ground.
Working in teams of two or three depending on the size of the gully and number of volunteers, we set a line across which we used to align the first piece of piling. This first piece was the most important because it determined the angle the piling would cross. If it deviated from the line, we had to restart, much to the merriment of the other volunteers (sorry guys). With all the piling in place, using a rubber mallet, it was tapered to the contour of the gully where the middle piece was required to be the lowest point (see Figure 1).
We installed 115 of these blocks and after revisiting some of the sites,the majority of them have proven to be very effective, though there are the odd few which have failed to retain as much water as we’d hoped. This is likely due to leaking joints in the piling or pipes in the peat which carry water to the bog catchment and further down the peat profile.
We’ve also been working with heather bale dams to slow the flow of water in areas unsuitable for large plastic/stone dams. If the gully’s aren’t blocked it’s likely they would become larger over time as they erode. These types of dams use natural moorland materials which typical moorland vegetation can grow, they also create shallow pools and improve the habitat for wading birds.
Large areas of heather are not only an issue in terms of biodiversity, but also in terms of being fuel to fires which tend to break out at random times, especially during summer. By removing heather in strategic ways, the scale of damage fires can have is reduced significantly. I’ve had the opportunity to cut some clearings across gully’s at Robinson’s Moss in anticipation for future fires. These clearings also create a better mosaic of habitats, particularly in wetter areas which are suitable for sphagnum reintroduction.
So far the work I’ve been involved in, whilst challenging at times, has given me some incredible experiences and a greater passion for preserving upland ecosystems which I expect will continue as I carry on.
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