Peatland restoration has become a common land-use management practice in recent years, with the water table depth (WTD) being one of the key monitoring elements, where it is used as a proxy for ...various ecosystem functions. Regular, uninterrupted, and spatially representative WTD data in situ can be difficult to collect, and therefore, remotely sensed data offer an attractive alternative for landscape-scale monitoring. In this study, we illustrate the application of Sentinel-1 SAR backscatter for water table depth monitoring in near-natural and restored blanket bogs in the Flow Country of northern Scotland. Among the study sites, the near-natural peatlands presented the smallest fluctuations in the WTD (with depths typically between 0 and 15 cm) and had the most stable radar signal throughout the year (~3 to 4 dB amplitude). Previously drained and afforested peatlands undergoing restoration management were found to have higher WTD fluctuations (depths up to 35 cm), which were also reflected in higher shifts in the radar backscatter (up to a ~6 dB difference within a year). Sites where more advanced restoration methods have been applied, however, were associated with shallower water table depths and smoother surfaces. Three models—simple linear regression, multiple linear regression, and the random forest model—were evaluated for their potential to predict water table dynamics in peatlands using Sentinel-1 SAR backscatter. The random forest model was found to be the most suited, with the highest correlation scores, lowest RMSE values, and overall good temporal fit (R2 = 0.66, RMSE = 2.1 cm), and multiple linear regression came in a close second (R2 = 0.59, RMSE = 4.5 cm). The impact of standing water, terrain ruggedness, and the ridge and furrow aspect on the model correlation scores was tested but found not to have a statistically significant influence. We propose that this approach, using Sentinel-1 and random forest models to predict the WTD, has strong potential and should be tested in a wider range of peatland sites.
Small mammals, such as small rodents (Rodentia: Muroidea) and shrews (Insectivora: Soricidae), present particular challenges in camera trap surveys. Their size is often insufficient to trigger ...infra-red sensors, whilst resultant images may be of inadequate quality for species identification. The conventional survey method for small mammals, live-trapping, can be both labour-intensive and detrimental to animal welfare. Here, we describe a method for using camera traps for monitoring small mammals. We show that by attaching the camera trap to a baited tunnel, fixing a close-focus lens over the camera trap lens, and reducing the flash intensity, pictures or videos can be obtained of sufficient quality for identifying species. We demonstrate the use of the method by comparing occurrences of small mammals in a peatland landscape containing (i) plantation forestry (planted on drained former blanket bog), (ii) ex-forestry areas undergoing bog restoration, and (iii) unmodified blanket bog habitat. Rodents were detected only in forestry and restoration areas, whilst shrews were detected across all habitat. The odds of detecting small mammals were 7.6 times higher on camera traps set in plantation forestry than in unmodified bog, and 3.7 times higher on camera traps in restoration areas than in bog. When absolute abundance estimates are not required, and camera traps are available, this technique provides a low-cost survey method that is labour-efficient and has minimal animal welfare implications.
Peatland restoration is undertaken to bring back key peatland ecosystem services, including carbon storage. In the case of drained, afforested blanket peatlands, restoration through drain blocking ...and tree removal may impact upon aquatic carbon concentrations and export, which needs to be accounted for when considering the carbon benefits of restoration.
This study investigated concentrations and export of aquatic carbon from a drained, afforested blanket bog catchment, where 12% of the catchment underwent drain blocking and conifer removal (termed ‘forest-to-bog’ restoration), and from two control catchments: one in open bog and one that remained afforested. Using a before-after-control-impact (BACI) design, we found no significant increases in concentrations or export of aquatic carbon (DOC, POC or DIC) in the first year following forest-to-bog restoration (i.e. across the whole post-restoration period). However, increased DOC concentrations were observed in the first summer (2015) post-restoration, and seasonally increased DOC export was noted during storm events in the autumn of the same year. The lack of significant effects of forest-to-bog restoration on aquatic carbon export may be a consequence of the small proportion of the catchment (12%) undergoing management. In terms of management, the removal of more of the forestry residues (i.e., brash) may help to mitigate effects on aquatic carbon, by removing a potential DOC and POC source. Restoring small areas at a time (≤12%) should result in minimal aquatic carbon export issues, in contexts similar to the current study.
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•We investigated short-term aquatic carbon losses following bog restoration.•There were no significant changes in aquatic carbon concentrations or exports.•Seasonally increased DOC concentrations may be associated with restoration.•Restoring small catchment portions (e.g., ≤12%), should minimise aquatic carbon losses.
Objective
We examine the relationships between contemporary progress in on‐road vehicle automation and its coherence with an envisioned “autopia” (automobile utopia) whereby the vehicle operation ...task is removed from all direct human control.
Background
The progressive automation of on‐road vehicles toward a completely driverless state is determined by the integration of technological advances into the private automobile market; improvements in transportation infrastructure and systems efficiencies; and the vision of future driving as a crash‐free enterprise. While there are many challenges to address with respect to automated vehicles concerning the remaining driver role, a considerable amount of technology is already present in vehicles and is advancing rapidly.
Methods
A multidisciplinary team of experts met to discuss the most critical challenges in the changing role of the driver, and associated safety issues, during the transitional phase of vehicle automation where human drivers continue to have an important but truncated role in monitoring and supervising vehicle operations.
Results
The group endorsed that vehicle automation is an important application of information technology, not only because of its impact on transportation efficiency, but also because road transport is a life critical system in which failures result in deaths and injuries. Five critical challenges were identified: driver independence and mobility, driver acceptance and trust, failure management, third-party testing, and political support.
Conclusion
Vehicle automation is not technical innovation alone, but is a social as much as a technological revolution consisting of both attendant costs and concomitant benefits.
During the restoration of degraded bogs and other peatlands, both habitat and functional recovery can be closely linked with nutrient cycling, which is reflected in pore- and surface-water chemistry. ...Several peatland restoration studies have shown that the time required for recovery of target conditions is slow (>10 years); for heavily-impacted, drained and afforested peatlands of northern Scotland, recovery time is unknown. We monitored pore- and surface-water chemistry across a chronosequence of formerly drained, afforested bog restoration sites spanning 0–17 years, using a space-for-time substitution, and compared them with open blanket bog control sites. Our aims were to measure rate of recovery towards bog conditions and to identify the best suite of water chemistry variables to indicate recovery.
Our results show progress in recovery towards bog conditions over a 0–17 year period post-restoration. Elements scavenged by trees (Mg, Na, S) completely recovered within that period. Many water chemistry variables were affected by the restoration process itself, but recovered within 11 years, except ammonium (NH4+), Zn and dissolved organic carbon (DOC) which remained elevated (when compared to control bogs) 17 years post restoration. Other variables did not completely recover (water table depth (WTD), pH), exhibiting what we term “legacy” effects of drainage and afforestation. Excess N and a lowered WTD are likely to slow the recovery of bog vegetation including key bog plants such as Sphagnum mosses.
Over 17 years, we measured near-complete recovery in the chemistry of surface-water and deep pore-water but limited progress in shallow pore-water. Our results suggest that at least >17 years are required for complete recovery of water chemistry to bog conditions. However, we expect that newer restoration methods including conifer harvesting (stem plus brash) and the blocking of plough furrows (to increase the WTD) are likely to accelerate the restoration process (albeit at greater cost); this should be evaluated in future studies. We conclude that monitoring pore- and surface-water chemistry is useful in terms of indicating recovery towards bog conditions and we recommend monitoring WTD, pH, conductivity, Ca, NH4+, phosphate (PO43−), K, DOC, Al and Zn as key variables.
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•After restoration, water chemistry progressed toward bog conditions over 17 years.•pH, NH4+ and WTD had not recovered completely within 17 years.•PO43− and K were released post-restoration, but levels recovered within 11 years.•We recommend monitoring WTD, pH, conductivity, Ca, NH4+, PO43−, K, DOC, Al and Zn.
Afforestation of formerly open landscapes can transform mammalian predator communities, potentially impacting prey species like ground‐nesting birds. In Scotland's Flow Country, a globally important ...peatland containing many forestry plantations, earlier studies found reduced densities of breeding waders on open bogs, when forestry plantations were present within 700 m. One plausible explanation for this pattern is mammalian predation. We tested whether mammalian predator indices, based on scats (feces), differed between (1) open bog, forestry plantations, and former plantations being restored as bog (“restoration” habitats); (2) restoration habitats of different ages; and (3) open bogs with differing amounts of nearby forestry. We measured summer scat density and size over 14 years in 26 transects 0.6–4.5 km in length, collecting data during 93, 96, and 79 transect‐years in bog, forestry, and restoration habitats respectively. In forestry, scat density increased eightfold, reaching values ~6 times higher than those of bogs. On open bogs with over 10% forestry within 700 m, scat densities were 2.9 times higher than on open bogs with less forestry nearby. Results support the hypothesis that mammalian predators might be responsible for the low densities of breeding waders close to forests, on adjacent open bogs. In restoration habitats, scat densities rose 6–10 years after felling but fell to levels similar to open bogs in older restoration habitats, supporting restoration management as a means of reducing mammalian predator activity/abundance. We urge caution around decisions to establish forestry plantations in open landscapes of high biodiversity importance.
The restoration of drained afforested peatlands, through drain blocking and tree removal, is increasing in response to peatland restoration targets and policy incentives. In the short term, these ...intensive restoration operations may affect receiving watercourses and the biota that depend upon them. This study assessed the immediate effect of ‘forest-to-bog’ restoration by measuring stream and river water quality for a 15 month period pre- and post-restoration, in the Flow Country peatlands of northern Scotland. We found that the chemistry of streams draining restoration areas differed from that of control streams following restoration, with phosphate concentrations significantly higher (1.7–6.2 fold, mean 4.4) in restoration streams compared to the pre-restoration period. This led to a decrease in the pass rate (from 100 to 75%) for the target “good” quality threshold (based on EU Water Framework Directive guidelines) in rivers in this immediate post-restoration period, when compared to unaffected river baseline sites (which fell from 100 to 90% post-restoration). While overall increases in turbidity, dissolved organic carbon, iron, potassium and manganese were not significant post-restoration, they exhibited an exaggerated seasonal cycle, peaking in summer months in restoration streams. We attribute these relatively limited, minor short-term impacts to the fact that relatively small percentages of the catchment area (3–23%), in our study catchments were felled, and that drain blocking and silt traps, put in place as part of restoration management, were likely effective in mitigating negative effects. Looking ahead, we suggest that future research should investigate longer term water quality effects and compare different ways of potentially controlling nutrient release.
Peatlands provide important ecosystem services including carbon storage and biodiversity conservation. Remote sensing shows potential for monitoring peatlands, but most off-the-shelf data products ...are developed for unsaturated environments and it is unclear how well they can perform in peatland ecosystems. Sphagnum moss is an important peatland genus with specific characteristics which can affect spectral reflectance, and we hypothesized that the prevalence of Sphagnum in a peatland could affect the spectral signature of the area. This article combines results from both laboratory and field experiments to assess the relationship between spectral indices and the moisture content and gross primary productivity (GPP) of peatland (blanket bog) vegetation species. The aim was to consider how well the selected indices perform under a range of conditions, and whether Sphagnum has a significant impact on the relationships tested. We found that both water indices tested normalized difference water index (NDWI) and floating water band index (fWBI) were sensitive to the water content changes in Sphagnum moss in the laboratory, and there was little difference between them. Most of the vegetation indices tested the normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), structure insensitive pigment index (SIPI), and chlorophyll index (CIm) were found to have a strong relationship with GPP both in the laboratory and in the field. The NDVI and EVI are useful for large-scale estimation of GPP, but are sensitive to the proportion of Sphagnum present. The CIm is less affected by different species proportions and might therefore be the best to use in areas where vegetation species cover is unknown. The photochemical reflectance index (PRI) is shown to be best suited to small-scale studies of single species.
The restoration of drained and afforested peatlands is carried out by removing trees and blocking forestry drains to reinstate key ecosystem services such as peatland habitat provision to support ...specialised biodiversity assemblages and carbon storage. Although restoration is a slow process, in the short-term, management interventions result in physical and biogeochemical disturbances, impacting upon pore- and surface-water quality. These impacts may vary depending on the restoration techniques used. Here, we compare the effects of two restoration techniques that both include blocking of main forestry drains but that vary in the amount of tree material removed from afforested sites: stem only harvesting (“standard harvesting”, STD) and whole tree harvesting (“enhanced harvesting”, ENH). We measured their short-term (0–1 year) effects on pore- and surface-water quality in a replicated BACI study. We assessed pore- and surface-water quality using principal response curves, comparing restoration treatments with afforested and open bog controls.
Our results showed the largest effects in surface- and shallow pore-water after restoration, where DOC, PO43−, NH4+ and K showed the greatest concentration increases, in both ENH and STD plots, relative to controls. Lesser increases were measured for Al, Ca, Fe and Mn concentrations. Meanwhile, in deep pore-water, water quality changed comparatively little during the study. We also found a post-restoration (mean) rise in water table of 10 cm in both ENH and STD treatments.
In general, ENH plots showed larger concentration increases in surface-water, likely related to the additional disturbance caused during brash removal (i.e. more intensive management). However, concentrations had begun to decline for many parameters by the end of the study, which was attributed to the removal of a major source of nutrients (brash) by this technique. In contrast, STD plots showed greater concentration increases in shallow pore-water, given (on average) a 5 cm shallower water table and with all brash remaining on site. Although longer-term monitoring would be required to test this, our results suggest that there remains merit in removing brash (compared to stem-only harvest) when considering longer-term recovery to bog.
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•Stem only harvest showed greater increases of PO43−, NH4+ and K in pore-water•Whole tree harvest showed greater surface-water increases in DOC, PO43−, NH4+ and K•Extra machine disturbance during whole tree harvest likely affected surface-water•Large brash volumes left after stem only harvest may continue to release nutrients•We suggest that whole tree harvest may aid more rapid recovery of water quality
Questions: Does restoration management of a formerly afforested blanket bog lead to the vegetation, and the environmental conditions it indicates, becoming similar to intact bog? Location: A 147-ha ...blanket bog in Scotland's Flow Country, afforested in the 1980s but undergoing restoration since 1998. Methods: Vegetation in the restoration area was surveyed in nine, 1.6–6.4-ha plots, in 1998, 2003 and 2011. Each plot was matched to nearby plots that were either intact bog or remained afforested. Principal Response Curves were used to highlight the main axes of vegetation variation and test whether plant community trajectories in the restoration area differed from intact bog. The following restoration outcomes were assessed: floristic similarity to bog vegetation; and moisture, fertility and acidity, as inferred from vegetation using Ellenberg indicator values. Results: In the 6 years after restoration began, vegetation developed towards bog-like conditions. In the subsequent 8 years, overall vegetation change stalled, and spatial variability increased, reflecting diverging trajectories in wetter and drier parts of the site. Ellenberg's F-values implied significant re-wetting in the restoration area, reaching moisture levels similar to intact bog. Other restoration outcomes progressed in wetter microsites and areas (furrows and flat ground), but stalled in drier locations (plough-ridges and steeper slopes). Conclusions: Overall moisture conditions, as indicated by plants, have recovered. However, restoration progress has stalled in drier areas, where additional management may be needed. Long-term vegetation monitoring has helped clarify barriers to recovery and the management needed to overcome them. The value of such monitoring schemes in guiding restoration should be reflected in their wider implementation, within an adaptive management framework.