The diversity and composition of moth assemblages of protected and degraded raised bogs in Ireland

1. Peatlands are a globally important habitat, which act as net carbon stores. Raised bogs in the midlands of Ireland are a diminishing and increasingly fragmented peatland habitat as a result of drainage, peat extraction and agricultural intensification. A network of protected sites has been established, which is intended to represent the best abiotic and plant community systems. 2. Lepidoteran communities are an important component raised bog biodiversity and may be useful as biodiversity indicators, yet they are a neglected area of research. We address this by surveying nocturnal lepidopteran communities on six degraded and six protected raised bogs. We collected 1,816 individuals (representing 93 species) across all sites. 2 3. Poisson generalised linear models were fitted to our count data and assessed using the Akaike information criterion (AIC) values. Models that included designation status were preferred for six species, three of which were more abundant on designated sites and three were more abundant on degraded sites. We discuss these findings in relation to the species’ known autecologies. Larval food plant choice, particularly due to the presence of invasive and non-typical plants, explained the alignment of species with undesignated sites. Other factors such as structural heterogeneity or nectar availability, may explain the alignment of most species with designated sites. 4. Rank abundance diagrams (RADs) of the total moth community were similar between protected and degraded sites, but the RADs of bog-associated species of conservation concern were different between protected and degraded sites with rarer bog associates being relatively better represented at the protected sites. This result was supported by Multi-response permutation-procedure (MRPP) analysis. 5. In general, differences between moth communities on degraded and protected raised bogs are rather subtle, with assemblages on both site types generally similar, but there is evidence that the “coarse filter” approach to conservation is working for some of the most important moth communities i.e. those that are bog-associated and of conservation concern. However, degraded sites may have a role to play in peatland invertebrate conservation, hitherto undervalued

A review of techniques for monitoring the success of peatland restoration

An important element of all peatland restorationprojects is a programme of monitoring to checkresults and progress. Several peat projectworkshops identified a demand for technicalguidance on monitoring techniques. So NaturalEngland commissioned this study to: -Review the range of peatland restorationmonitoring techniques available. -Identify those that were consistent, informativeand easily applicable for peatland restorationprojects at a range of scales and budgets.Tables to identify appropriate monitoringtechniques for specific projects are published inthe Technical Information Note TIN097 -Guidelines for monitoring peatland restoration.Further information on these techniques isprovided in this report.The findings of this study have been used to: -Inform the JNCC project to design a researchprogramme on UK Peatland Green House Gasand Carbon Flux. -Develop thinking on monitoring peatlands inthe IUCN UK Peatland Programme. -Inform hydrological monitoring programmes forthe Dartmoor and Exmoor Mires Project.These findings are being disseminated to: -Encourage the use of balanced and consistentapproaches to peatland restoration monitoring. -Develop consistency in monitoring approachesso as to enable possible future collation ofpeatland monitoring data as a single databaseresource.A single database resource of peatlandrestoration would enable more robust analysesof monitoring data to support the developmentand implementation of future support andmanagement techniques for peatlandrestoration

Nocturnal Lepidoptera of Midland Raised Bogs

Raised bogs started to form in Ireland at least 7000 years ago when peat started to accumulate in water-filled depressions left after the last glacial period. Due to centuries of damaging human activities, only 1% of the living, growing active raised bog habitat remains and this is rapidly being lost. Raised bogs are important reservoirs of biodiversity, hosting many uniquely adapted plant and animal species and are of high conservation concern internationally. The aims of this study were to objectively assess the potential of macro-moths as active raised bog biodiversity indicators, to collate baseline information on the distribution of this fauna on threatened midland raised bog habitat and to identify species with restricted distributions which may be of conservation concern. Macro-moths were sampled using light-traps on twelve midland raised bogs from early July to the end of October in 2011. Six high conservation value bogs designated as Special Areas of Conservations (SACs) and six undesignated and degraded bogs were surveyed. A total of 1,816 adult individuals of 93 moth species were recorded, representing 16% of the Irish moth fauna. Four species new to County Offaly were recorded. Only two potential indicator species of active raised bog were found, with only one species (Acronicta menyanthidis (Esper, 1789)) significantly correlated with the wettest areas of active raised bog (P = 0.01). Raised bog associated nocturnal macro-moth assemblages showed a significantly nested structure (P < 0.01), common in fragmented habitats, whereby species-poor sites form a nested subset of species-rich sites. The difference between designated and undesignated raised bog associated moth assemblages was significant (A = 0.044; P = 0.038), but within group homogeneity was low. As designated and undesignated bogs contain assemblages which are broadly similar, the findings of this study would suggest that even degraded undesignated raised bog remnants, may be of significant conservation value for macro-moth species

Laboratory investigation of the ignition and spread of smouldering in peat samples of different origins and the associated emissions

Tackling peatland wildfires, the largest fires on Earth in terms of fuel consumption, is an emerging combustion topic in the context of climate change. The understanding of fundamental smouldering dynamics and their application to peatlands are essential to mitigation methodologies’ development, but not yet fully understood in the literature. Most of the previous laboratory smouldering studies used horticultural peat which has a great advantage in controlling the influential factors, but has lower bulk density, and is not representative of some higher bulk density peat found in the field. In this thesis, a series of laboratory experiments were conducted to investigate the critical ignition conditions and governing fire spread parameters of smouldering in peat of various origins, and to quantify the associated emissions. To better understand natural variations, field samplings were conducted in Sumatra, Indonesia and Flow Country, Scotland. In addition, five types of horticultural peat were studied. The results show high bulk density peat from long-term drained peatlands experiences more extensive burning in terms of the amount of carbon and particle emitted, while newly drained peat with low bulk density is more vulnerable to fire in terms of easier ignition and faster fire spread. Evidence was found in this thesis that the heat sink density and the organic density, not only control horizontal spread and in-depth spread, but also determine ignition probability. Furthermore, as smouldering is multidimensional, a critical angle of spread direction (65˚ relative to horizontal plane) above which smouldering cannot self-sustain was found. By studying the emissions of different types of peat, the modified combustion efficiency (MCE) range for smouldering was broadened to 0.74 – 0.88, and found to be significantly dependent on the fuel composition. This thesis provides a better understanding of how smouldering wildfires start and spread in different types of peat and the associated emissions, thus contributing to prevention and mitigation.Open Acces

Review of existing information on the interrelations between soil and climate change. (ClimSoil). Final report

Carbon stock in EU soils – The soil carbon stocks in the EU27 are around 75 billion tonnes of carbon (C); of this stock around 50% is located in Sweden, Finland and the United Kingdom (because of the vast area of peatlands in these countries) and approximately 20% is in peatlands, mainly in countries in the northern part of Europe. The rest is in mineral soils, again the higher amount being in northern Europe. 2. Soils sink or source for CO2 in the EU – Both uptake of carbon dioxide (CO2) through photosynthesis and plant growth and loss of CO2 through decomposition of organic matter from terrestrial ecosystems are significant fluxes in Europe. Yet, the net terrestrial carbon fluxes are typically 5-10 times smaller relative to the emissions from use of fossil fuel of 4000 Mt CO2 per year. 3. Peat and organic soils - The largest emissions of CO2 from soils are resulting from land use change and especially drainage of organic soils and amount to 20-40 tonnes of CO2 per hectare per year. The most effective option to manage soil carbon in order to mitigate climate change is to preserve existing stocks in soils, and especially the large stocks in peat and other soils with a high content of organic matter. 4. Land use and soil carbon – Land use and land use change significantly affects soil carbon stocks. On average, soils in Europe are most likely to be accumulating carbon on a net basis with a sink for carbon in soils under grassland and forest (from 0 - 100 billion tonnes of carbon per year) and a smaller source for carbon from soils under arable land (from 10 - 40 billion tonnes of carbon per year). Soil carbon losses occur when grasslands, managed forest lands or native ecosystems are converted to croplands and vice versa carbon stocks increase, albeit it slower, following conversion of cropland. 5. Soil management and soil carbon – Soil management has a large impact on soil carbon. Measures directed towards effective management of soil carbon are available and identified, and many of these are feasible and relatively inexpensive to implement. Management for lower nitrogen (N) emissions and lower C emissions is a useful approach to prevent trade off and swapping of emissions between the greenhouse gases CO2, methane (CH4) and nitrous oxide (N2O). 6. Carbon sequestration – Even though effective in reducing or slowing the build up of CO2 in the atmosphere, soil carbon sequestration is surely no ‘golden bullet’ alone to fight climate change due to the limited magnitude of its effect and its potential reversibility; it could, nevertheless, play an important role in climate mitigation alongside other measures, especially because of its immediate availability and relative low cost for 'buying' us time. 7. Effects of climate change on soil carbon pools – Climate change is expected to have an impact on soil carbon in the longer term, but far less an impact than does land use change, land use and land management. We have not found strong and clear evidence for either overall and combined positive of negative impact of climate change (atmospheric CO2, temperature, precipitation) on soil carbon stocks. Due to the relatively large gross exchange of CO2 between atmosphere and soils and the significant stocks of carbon in soils, relatively small changes in these large and opposing fluxes of CO2, i.e. as result of land use (change), land management and climate change, may have significant impact on our climate and on soil quality. 8. Monitoring systems for changes in soil carbon – Currently, monitoring and knowledge on land use and land use change in EU27 is inadequate for accurate calculation of changes in soil carbon contents. Systematic and harmonized monitoring across EU27 and across relevant land uses would allow for adequate representation of changes in soil carbon in reporting emissions from soils and sequestration in soils to the UNFCCC. 9. EU policies and soil carbon – Environmental requirements under the Cross Compliance requirement of CAP is an instrument that may be used to maintain SOC. Neither measures under UNFCCC nor those mentioned in the proposed Soil Framework Directive are expected to adversely impact soil C. EU policy on renewable energy is not necessarily a guarantee for appropriate (soil) carbon management

The effect of drainage ditches on vegetation diversity and CO2 fluxes in a Molinia caerulea dominated peatland

AcceptedArticleCopyright © 2015 John Wiley & Sons, Ltd.Peatlands are recognized as important carbon stores; despite this, many have been drained for agricultural improvement. Drainage has been shown to lower water tables and alter vegetation composition, modifying primary productivity and decomposition, potentially initiating peat loss. To quantify CO2 fluxes across whole landscapes, it is vital to understand how vegetation composition and CO2 fluxes vary spatially in response to the pattern of drainage features. However, Molinia caerulea-dominated peatlands are poorly understood despite their widespread extent. Photosynthesis (PG600) and ecosystem respiration (REco) were modelled (12 °C, 600 µmol photons m−2 s−1, greenness excess index of 60) using empirically derived parameters based on closed-chamber measurements collected over a growing season. Partitioned below-ground fluxes were also collected. Plots were arranged ⅛, ¼ and ½ the distance between adjacent ditches in two catchments located in Exmoor National Park, southwest England. Water table depths were deepest closest to the ditch and non-significantly (p = 0·197) shallower further away. Non-Molinia species coverage and the Simpson diversity index significantly decreased with water table depth (p < 0·024) and increased non-significantly (p < 0·083) away from the ditch. No CO2 fluxes showed significant spatial distribution in response to drainage ditches, arguably due to insignificant spatial distribution of water tables and vegetation composition. Whilst REco showed no significant spatial variation, PG600 varied significantly between sites (p = 0·012), thereby controlling the spatial distribution of net ecosystem exchange between sites. As PG600 significantly co-varied with water table depths (p = 0·034), determining the spatial distribution of water table depths may enable CO2 fluxes to be estimated across M. caerulea-dominated landscapes. © 2015 The Authors. Ecohydrology published by John Wiley & Sons, Ltd.South West WaterThe University of Exete

Carbon fluxes at an upland blanket bog in the north Pennines

The peat soils found in blanket bogs are significant stores of carbon. The degree to which these ecosystems are currently functioning as sinks or sources of carbon is not clear. There is a paucity of measurements from suitable sites but the available evidence suggests that certain sites might be close to being carbon neutral or acting as a net source of carbon to the atmosphere. A complete understanding of the carbon budget of a landscape requires a comprehensive assessment of the magnitude of the whole range of pathways by which carbon enters and leaves the system. Measurements were made of all of the key gaseous carbon fluxes, including the net CO2 flux, the soil CO2 flux and emissions as methane. A flux partitioning model was utilised to separate the net CO2 flux into its component parts. Values for the fluvial carbon losses from the site were taken from the literature. The various CO2 fluxes were by far the largest terms in the complete carbon budget. Growing season measurements showed that methane emissions were a small component. The key environmental variables that were driving the temporal variations in the fluxes were identified. In general soil temperature was important in explaining variations in ecosystem respiration, soil CO2 fluxes and the methane flux. The water table was usually high and fluctuations did not appear to affect carbon fluxes. There was evidence of increased soil CO2 fluxes as a response to low soil moisture levels during a summer dry period. A comprehensive carbon budget for the blanket bog at Moor House NNR showed the site to be a relatively large carbon sink, of an estimated 134.09 ± 32 g C m-2 yr-1