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This study estimates the complete carbon budget of an 11.4 km 2 peat-covered catchment in Northern England. The budget considers both fluvial and gaseous carbon fluxes and includes estimates of particulate organic carbon (POC); dissolved organic carbon (DOC); excess dissolved CO 2 ; release of methane (CH 4 ); net ecosystem respiration of CO 2 ; and uptake of CO 2 by primary productivity. All components except CH 4 were measured directly in the catchment and annual carbon budgets were calculated for the catchment between 1993 and 2005 using both extrapolation and interpolation methods. The study shows that: Over the 13 year study period the total carbon balance varied between a net sink of − 20 to − 91 Mg C/km 2 /yr. The biggest component of this budget is the uptake of carbon by primary productivity (− 178 Mg C/km 2 /yr) and in most years the second largest component is the loss of DOC from the peat profile (+39 Mg C/km 2 /yr). Direct exchanges of C with the atmosphere average − 89 Mg C/km 2 /yr in the catchment. Extrapolating the general findings of the carbon budget across all UK peatlands results in an approximate carbon balance of − 1.2 Tg C/ yr (±0.4 Pg C/yr) which is larger than previously reported values. Carbon budgets should always be reported with a clear statement of the techniques used and errors involved as this is significant when comparing results across studies.

Peatlands are among the largest long-term soil carbon stores, but their degradation can lead to significant carbon losses. This study considers the carbon budget of peat-covered sites after restoration, following degradation by past wildfires. The study measured the carbon budget of eight sites: four restored-revegetated sites, two unrestored bare soil control sites, and two intact vegetated controls over two years (2006)(2007)(2008). The study considered the following flux pathways: dissolved organic carbon (DOC); particulate organic carbon (POC); dissolved carbon dioxide (CO 2 ); primary productivity; net ecosystem respiration, and methane (CH 4 ). The study shows that unrestored, bare peat sites can have significant carbon losses as high as 522 ± 3 tonnes C/km 2 /yr. Most sites showed improved carbon budgets (decreased source and/or increased sink of carbon) after restoration; this improvement was mainly in the form of a reduction in the size of the net carbon source, but for one restored site the measured carbon budget after four years of restoration was greater than observed for vegetated controls. The carbon sequestration benefit of peatland restoration would range between 122 and 833 tonnes C/km 2 /yr.

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This study measures the complete carbon budget of a drained peat-covered catchment. It includes dissolved organic carbon (DOC), particulate organic carbon (POC), dissolved CO 2 , primary productivity, soil respiration of carbon dioxide (CO 2 ) and methane (CH 4 ) in contrast to other studies which have focused on only some of the possible carbon uptake and release pathways; values for rainfall inputs were taken from a nearby catchment. The study is based on data collected over 2 yr for two drain catchments within one site and the main findings are: 1. The catchments were a net source of all forms of carbon at between +63.8 and +106.8Mg C ⁄ km 2 ⁄ yr; 2. There was a net loss of between +9.3 and +40.7 Mg C ⁄ km 2 ⁄ yr in terms of exchange of carbon with the atmosphere; 3. The small size of the study catchments seems to have resulted in higher values of exported DOC than recorded elsewhere and the highly disturbed drainage of the site may have given rise to losses in net ecosystem exchange (NEE). If the fate of the peatland carbon store is to be understood, then it is important that all carbon uptake and release pathways are considered and not just components of the carbon cycle.

This study aimed to measure the effects of ecological restoration on blanket peat water in and around the gullies investigated whereas a blocked gully has water table depths comparable to a naturally revegetating gully. A 10 cm lowering in water table depth decreases the probability of observing a net CO2 sink, on a given site, by up to 30 %. The most i mportant conclusion of this research was that restoration interventions are effective at increasing the likelihood of net CO2 sink behaviour and raising water tables on degraded, climatically marginal blanket bog.

UK peatlands are affected by severe gully erosion with consequent impacts on ecosystem services from these areas. Incision into the peat can damage the vegetation and hydrology and lead to increases in carbon loss and sediment transfer downstream. Gullies represent then a conduit for and a hotspot of carbon loss but the relatively high water tables of gullies have meant that they have been identified as areas with a high restoration potential because of easily restored peat‐forming conditions. This study uses a series of gully sites, subject to different restoration interventions, to investigate differences in carbon pathways (DOC, CO2) and hydrology between restoration strategies and gully position. The results show that the position within the gully (interfluve, gully side, or gully floor) does not significantly affect water quality but that it plays a significant role in CO2 exchange. Gully floors are areas of high photosynthesis and ecosystem respiration, though net ecosystem exchange is not significantly different across the gully. While gully position plays a role in the cycling of some carbon species, this study highlights the importance of vegetation as a key control on carbon cycling. Copyright © 2012 John Wiley & Sons, Ltd.

In northwest Europe, large areas of open peatland have been drained and planted with spatially homogenous stands of non-native conifers. The detrimental impact of afforestation on peatland carbon and biodiversity have led to large-scale attempts to restore these landscapes back to their open, tree-less form. The responses of dominant microbial consumers-testate amoebae-to peatland forest-to-bog restoration are largely unexplored. We studied changes in testate amoebae with forest-to-bog restoration in the largest expanse of blanket bog in the UK and compared testate amoeba communities in relatively undisturbed open bog with forested and forest-to-bog restoration sites. Forested areas contained testate amoeba communities which were functionally different from open bog, characterised by a lack of mixotrophic taxa known to contribute to primary production. Seventeen years after restoration management, the microbial communities in the forest-to-bog sites remained more similar to forested areas than to the open bog community. Our results suggest that afforestation has reduced the trophic level of testate amoeba communities, which are only beginning to recover post-restoration in the wettest areas where Sphagnum has re-colonized. This study also highlights the need to consider a wide-range of reference sites to encompass the natural variability within ombrotrophic blanket bog. We conclude that testate amoebae have the potential to act as functionally-significant bio-indicators in peatlands undergoing forest-to-bog restoration.