The objective of the workshop was to explore ideas on the best approaches and tools for monitoring peatlands, to contribute to the development of a Peatland Monitoring Toolkit. The expected outcomes were the identification of key factors/techniques/approaches/tools that can indicate the progress and success of peatland restoration projects, and an assessment of empirical data required to monitor progress against targets.
The tasks were as followed:
1. The workshop was split into 2 groups: Group 1- upland peat, and Group 2- lowland peat 2. Each group first decided on the purpose of restoration.
3. The principal monitoring techniques were discussed along with sampling protocol (spatial/temporal) used to establish the progress/success of restoration. The following questions were considered:
a. What are the pros and cons for each technique?
b. What about pre- and post-restoration monitoring and the type of restoration technique(s)?
c. What do we know about the costs and benefits of your monitoring techniques?
d. What baseline and target data are currently used to evaluate the success of restoration?
4. Finally, the groups were asked what they have learnt that may help others?
A2.1. Uplands
There were a number of reasons discussed for restoring upland peat which are listed in Box 1.
However, there was no consensus as to which was the most important reason for restoring peat but an indication that restoration might have multiple objectives such as the habitat type, funding source, stakeholder views and especially socio-economic priorities. There was a suggestion that restoring for biodiversity would restore ecosystem integrity that could support the other restoration purposes such as the favourable condition objective of Natural England. Others suggested that not everything can be restored via biodiversity restoration e.g. greenhouse gas balance. Indeed, there is probably not enough scientific evidence yet to determine whether restoration for biodiversity does in fact reduce greenhouse gas emissions or increase water quality. The importance of restoration purpose was obvious from results presented for Wicken Fen that showed that standing water above the soil surface was required to increase the soil carbon (C) store, but that this environmental condition was adverse to the situation required by the Biodiversity Action Plan for the habitat.
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Box 1 Ecological and socio-economic reasons for restoring upland peatland Biodiversity
Vegetation
composition/cover/structure Carbon storage/sequestration Reducing greenhouse gas emissions Water table depth
Water quality/supply Flood risk management Cultural heritage
Paleoenvironmental evidence Achieving conservation status
So, what are the favourable conditions of peat and how do you determine those conditions?
Suggestions included characteristic plant species and a low level of impact from grazing/draining.
Agreement was reached that no loss of peat or chemical change in the peat was a major restoration task which may not be achievable in practice and that the objective of restoration needs clear definition prior to even pre-restoration monitoring. Also, consideration is required as to whether the site can even be restored to the desired target if there is one.
Techniques used for monitoring success of restoration were varied but the presence of Sphagnum and the species of Sphagnum were considered very important (e.g S. palustre) as indicators of restoration success. Raising the water table was clearly a key method to achieve the objective of restoration success and this is closely tied to the development of Sphagnum. The diverse array of monitoring techniques included weather stations, dipwells, piezometers, runoff traps, erosion pins, photographic monitoring, vegetation cover/composition, gas collars for GHGs, invertebrates, fauna, testate amoeba (indicator of past hydrology), breeding bird surveys, microbiology and remote sensing. Sustainability of the restoration was considered very important. However, it was not clear how you can establish sustainability without long-term monitoring.
A number of projects included pre-restoration monitoring although this was dependent on planning and funding and may be associated with academic research as well as restoration projects. Baseline data (pre-restoration) was considered key to evaluation of restoration success. Some suggested that we need to know the condition of peat in order to achieve our objectives although it appears that very little pre-restoration monitoring occurs. In some cases restored sites have been compared to unrestored sites. Costs of monitoring can be low especially where volunteers have been used.
However, hydrological monitoring and remote sensing can be expensive. It was felt that there is a difference between what you can do and what you want to do. Also, how frequently do you monitor? Storm events are not always captured by routine measurements.
Many experts felt that “we don’t know where we want to get to” in terms of restoration targets.
Different sites are restored based on different objectives and criteria as listed in Box 1. This leads to the requirement for different monitoring techniques for measuring success as the success of the restoration depends on the type of restoration, and the ultimate purpose of the restoration. How do you define the target of restoration? Drift in both the baseline and target are likely due to climate or other environmental change. Are we really aiming for pristine conditions in peatlands or is that an unrealistic goal? Active management in stages is suggested where monitoring of restoration changes over time, dependent on the restoration targets of the peatland.
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There does appear to be a requirement for guidance on monitoring the trajectory of peatland restoration particularly using cost effective techniques. However, it was argued that standardization of monitoring methods would stop moving innovative research forward. It appears that extensive monitoring occurs where it is funded by academic research, but monitoring is lacking where simple habitat restoration is the objective rather than gaining a clearer understanding of the restoration ecology of peatlands. Thus links between bodies such as universities and non-academic bodies involved in funding and managing restoration projects could be important. However, monitoring techniques are used in restoration projects and substantial monitoring data has been collected although there has been little if any evaluation of the available evidence base. Research is probably driven by the goals of C storage rather than restoration of the peatland to a functioning ecosystem (i.e. provider of multiple ecosystem services). It was even argued that we have not actually started restoration yet and are currently stabilising/maintaining peatlands by preventing degradation.
Alternative policy drivers such as the need for rural regeneration and increase in socio-economic benefits will require alternative monitoring objectives to be included.
Summary of key points
1. Monitoring protocols depend on purpose/objectives of restoration.
2. We are still unsure about the nature and practical attainability of targets (and sometimes) baselines. This is complicated by a moving envelope of boundary conditions determining peat development and status.
3. Planning and funding are major concerns.
A2.2. Lowlands
The principle restoration methods for lowland peat were blocking drains, felling trees, raising ground water levels, landscape change, and reducing the cover of purple moor-grass. However, there was discussion as to whether restoration or creation was the objective, for example, Wicken Fen is an important restoration project but there is no bog there. Also, the question was stressed over whether restoration should aim for the most sustainable habitat rather than the most bio-diverse.
The drivers for restoration were PSA, BAP and HLS targets and it was mentioned that one objective of restoration should be to aim to restore the functions attributed to biogeochemical processes in wetlands rather than short-term gains. As an example, it was suggested that bunded grazing marsh would be better at Wicken Fen than fen or bog as that type of wetland would be more sustainable in the long-term.
Monitoring techniques appeared to overlap with those techniques applied to upland peat particularly hydrology and vegetation (Sphagnum indicators). Hydrological techniques included monitoring of water levels (dipwells, piezometers, automated pressure recorders, notch weirs/gauges/stage boards and determination of water flow in drains). In terms of water and peat quality, redox, pH, temperature and soil chemistry were deemed necessary though some of these parameters were poorly understood by some practitioners. Physical swelling groundwater effects and lunar cycle can alter water levels by 30 cm. The periodicity of the dipwell/piesometer readings is therefore very important and should be related to lunar cycle too.
Sphagnum cover was stressed as an important proxy for both water level and quality as well as peat surface conditions. Also, NVC characterization was deemed of importance such as signs of M17 being worth restoring but that M25 present could complicate restoration efforts. Research at Thorne &
Hatfield moors (http://www.thmcf.org/home.html) has shown that the vegetation changes with the
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wetting up. Initially indicator species were used and then a little more detail to NVC communities, also CSM.
Invertebrates and fungi were also considered possible indicators of restoration but might also be objectives. However, invertebrate monitoring was considered costly in which case invertebrates would best be monitored where they are deemed a special feature of a site in which case it would be an objective which could be directly monitored. Indicator species could be used to relate data sets to track changes in your variable of interest e.g. on the R. Tees there are fish spawning data which has been found to tie in with other environmental data and the fish records go back much further than the other set so assumptions can be made. Also, seasonality of fungi fruiting bodies has been related to environmental data.
Peat loss/accretion/erosion was considered an important monitoring variable. Lidar penetrating radar can be used to determine the density of peat and the EA fly regularly in lowlands but at different times of the year. Also, the height from a bridge or ground anchors can be used. However, caution was stressed as GPS and Ordinance can conflict and be 5-10cm out – height of raised mires can vary up to foot in a year depending on water input.
Only two sites monitored greenhouse gas exchange and only methane appears to have been measured.
Fixed point photography was deemed important but often not well used. It was suggested that it can be used horizontally or vertically. Good to record every quarter to see seasonal changes and to use aerial photos where possible.
Any monitoring protocol will depend on money and time available to record the site as well as the response time of the vegetation/hydrology to the changed circumstances. The ‘what’ and ‘why’ you are monitoring will determine the periodicity of monitoring. Common Standards Monitoring (CSM) could potentially be used for measuring success.
For long term monitoring, it is crucial to use the same methods throughout and these must be written into site management plan. Dipwells must tie into the datum and climate data. Good baseline data crucial but generally felt to be a paucity of such information. In terms of recording of monitoring data, long term funding stream required with cost effective monitoring techniques and survey protocols i.e. frequency.
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