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The effect of tree (lodgepole pine) planting with and without intensive drainage on soil greenhouse gas fluxes was assessed after 45 yr at a raised peatbog in West Flanders Moss, central Scotland. Fluxes of CO2, CH4 and N2O from the soil were monitored over a 2-yr period every 2 to 4 weeks using the static opaque chamber method in a randomised experimental block trial with the following treatments: drained and planted (DP), undrained and planted (uDP), undrained and unplanted (uDuP), and for reference also from an adjoining near pristine area of bog at East Flanders Moss (n-pris). There was a strong seasonal pattern in both CO2 and CH4 effluxes which were significantly higher in late spring and summer months, reflecting seasonal temperature changes. Effluxes of N2O were low and no significant differences were observed between the treatments. Annual CH4 emissions increased with the proximity of the water table to the soil surface across treatments in the order: DP 4ha-1 yr-1, respectively. For CO2, effluxes increased in the order uDP2ha-1 yr-1, respectively. CO2 effluxes dominated the calculated global warming potential (GWP) of the net fluxes for each treatment (76-98 %), and only in the n-pris site was CH4 a substantial contribution (23%). Based on soil effluxes only, the near pristine (n-pris) peatbog had 43% higher net GWP compared with the DP treatment because of high CH4 effluxes and the DP treatment had 33% higher GWP compared with the uDP because drainage increased CO2 effluxes. Restoration is likely to increase CH4 emissions, but reduce CO2 effluxes. Including estimates of CO2 uptake by vegetation from similar peatbog sites suggests that the total GWP of restored peatbog would be about half that of the peatbog covered by woodland. [ABSTRACT FROM AUTHOR]

Outgassing of carbon dioxide (CO 2 ) from river surface waters, estimated using partial pressure of dissolved CO 2 , has recently been considered an important component of the global carbon budget. However, little is still known about the high-frequency dynamics of CO 2 emissions in small-order rivers and streams. To analyse such highly dynamic systems, we propose a time-varying functional principal components analysis (FPCA) for non-stationary functional time series (FTS). This time-varying FPCA is performed in the frequency domain to investigate how the variability and auto-covariance structures in a FTS change over time. This methodology, and the associated proposed inference, enables investigation of the changes over time in the variability structure of the diurnal profiles of the partial pressure of CO 2 and identification of the drivers of those changes. By means of a simulation study, the performance of the time-varying dynamic FPCs is investigated under different scenarios of complete and incomplete FTS. Although the time-varying dynamic FPCA has been applied here to study the daily processes of consuming and producing CO 2 in a small catchment of the river Dee in Scotland, this methodology can be applied more generally to any dynamic time series.Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

Northern peatlands play an important role in the regulation of the atmospheric greenhouse gas (GHG) balance, functioning as a net carbon sink with low rates of organic decomposition. However, perturbations such as drainage increase peat oxidation, which may lead to enhanced gaseous release of carbon. For this reason, the number of restoration projects that aim to rewet blanket bogs has increased in the last few years, but there is still a lack of understanding of the impact of restoration on emissions of greenhouse gases, such as methane, particularly in sites restored from forestry. In this paper, we investigate the seasonal greenhouse gas dynamics in a forest‐to‐bog restoration site in Scotland. We analyse the effects of restoration on both carbon dioxide and methane fluxes, and investigate which site factors (microtopography, vegetation type, soil moisture and temperature) drive the processes of gaseous exchange between the bog surface and the atmosphere. Our results show that the original surface is near greenhouse gase equilibrium at −0.28 gCO2eq m2·day−1 and that microtopographic features act as a net greenhouse gas sink (ridges = −0.94 gCO2eq m2·day−1 and furrows = −0.86 gCO2eq m2·day−1), whereas the bog pool is a net source of greenhouse gases (0.98 gCO2eq m2·day−1). We found different vegetation species play a key role in greenhouse gas flux dynamics, especially in forestry‐derived microtopographical features, and their presence and influence on greenhouse gas dynamics should be accounted for to provide a more comprehensive understanding of emissions associated with restoration management practices. Highlights: GHG (CO2 and CH4) dynamics in a boreal peatland restored from forestry are mainly affected by microtopography and vegetation.Forestry‐derived microforms (ridges and furrows) are better GHG sinks than pools (GHG emitters) and original surfaces (near GHG equilibrium).The presence of Trichophorum cespitosum leads to higher CH4 emissions.Restoration practices like terraforming may create a short‐term pulse net GHG emission due to an increase of both CH4 and CO2 fluxes. [ABSTRACT FROM AUTHOR]

Scottish tourism is forecasted to grow by 50 per cent over the next 10 years but one of the factors that may hinder or facilitate that growth is climatic change. Indeed, many people are now starting to question the impact of such significant growth on the planet. Therefore, this paper assesses the impact of climate change on Scottish tourism in order that policy makers can separate the facts from the myths. The dimensions of climate change such as CO2 emissions, temperature, rainfall, storms, and wind speed are discussed and the implications for Scottish tourism are mapped. Those implications may include the introduction of CO2 allowances for all travellers, more wind farms in rural locations impacting on film tourism or the grouse species disappearing from Scotland. The paper concludes with a number of adaptation strategies that Scottish tourism agencies and business could adopt to mitigate climate change. The importance of this paper lies in understanding how climate change could impact upon a specific destination, in this case Scotland, and in providing a micro analysis of that impact. [ABSTRACT FROM AUTHOR]

• Urban wastewater, mine water and agricultural inputs dominated GHG generation. • Anthropogenic urban nutrient sources disproportionality increased GHGs in summer. • Low oxygen and high riverine residence time increased nutrient impacts on GHGs. • A source-to sea methodology enabled easy identification of GHG sources and sinks. • Load appointment modelling enabled separation of point and diffuse GHG sources. There is growing global concern that greenhouse gas (GHG) emissions from water bodies are increasing because of interactions between nutrient levels and climate warming. This paper investigates key land-cover, seasonal and hydrological controls of GHGs by comparison of the semi-natural, agricultural and urban environments in a detailed source-to-sea study of the River Clyde, Scotland. Riverine GHG concentrations were consistently oversaturated with respect to the atmosphere. High riverine concentrations of methane (CH 4) were primarily associated with point source inflows from urban wastewater treatment, abandoned coal mines and lakes, with CH 4 -C concentrations between 0.1 - 44 µg l−1. Concentrations of carbon dioxide (CO 2) and nitrous oxide (N 2 O) were mainly driven by nitrogen concentrations, dominated by diffuse agricultural inputs in the upper catchment and supplemented by point source inputs from urban wastewater in the lower urban catchment, with CO 2 -C concentrations between 0.1 - 2.6 mg l−1 and N 2 O-N concentrations between 0.3 - 3.4 µg l−1. A significant and disproportionate increase in all GHGs occurred in the lower urban riverine environment in the summer, compared to the semi-natural environment, where GHG concentrations were higher in winter. This increase and change in GHG seasonal patterns points to anthropogenic impacts on microbial communities. The loss of total dissolved carbon, to the estuary is approximately 48.4 ± 3.6 Gg C yr−1, with the annual inorganic carbon export approximately double that of organic carbon and four times that of CO 2, with CH 4 accounting for 0.03%, with the anthropogenic impact of disused coal mines accelerating DIC loss. The annual loss of total dissolved nitrogen to the estuary is approximately 4.03 ± 0.38 Gg N yr−1 of which N 2 O represents 0.06%. This study improves our understanding of riverine GHG generation and dynamics which can contribute to our knowledge of their release to the atmosphere. It identifies where action could support reductions in aquatic GHG generation and emission. [Display omitted] [ABSTRACT FROM AUTHOR]

Open‐water perennial pools are common natural features of peatlands globally, and peatland restoration often results in new pool creation, yet the concentrations of different forms of aquatic carbon (C) in natural and artificial restoration pools are not well studied. We compared carbon concentrations in both natural pools and restoration pools (4–15 years old) on three blanket peatlands in northern Scotland. At all sites, restoration pools were more acidic and had mean dissolved organic carbon (DOC) concentrations in restoration pools of 23, 22, and 31 mg L−1 compared with natural pool means of 11, 11 and 15 mg L−1 respectively across the three sites. Restoration pools had a greater fulvic acid prevalence than the natural pools and their DOC was more aromatic. Restoration pools were supersaturated with dissolved CO2 at around 10 times atmospheric levels, whereas for natural pools, CO2 concentrations were just above atmospheric levels. Dissolved CH4 concentrations were not different between pool types, but were ~200 times higher than atmospheric levels. Regular sampling at one of the peatland sites over 2.5 years showed that particulate organic carbon (POC) concentrations were generally below 7 mg L−1 except during the warm, dry summer of 2013. At this regularly‐sampled site, natural pools were found to process DOC so that mean pool outflow concentrations in overland flow were significantly lower than mean inflow DOC concentrations. Such an effect was not found for the restoration pools. Soil solution and pool water chemistry, and relationships between DOC and CO2 concentrations suggest that different processes are controlling the transformation of C, and therefore the form and amount of C, in natural pools compared to restoration pools. [ABSTRACT FROM AUTHOR]

Abstract: Scotland''s 17% forested land cover sequesters 10% of Scotland''s emissions of greenhouse gases. The expected rise of forested land cover to 25% by the middle of this century make forests an important component of the national carbon budget. This paper presents the carbon exchange measurement methodology, results, and modeling associated with a five-year experiment at a plantation forest in Scotland, UK, as part of a European initiative to develop and verify vegetation carbon-exchange models. We have developed a site specific correction for advective flux loses. While based on ustar corrections, it differs from current approaches in that it includes site topographic effects, corrects existing data instead of replacing it, and applies over the entire diel cycle instead of only during nocturnal periods. Models of soil respiration are compared and reveal the inadequacy of soil state parameterization. A non-rectangular hyperbola model of assimilation is selected to examine the maximum assimilation rate and quantum use efficiency parameters’ responses to environmental temperature, vapour pressure, and sky condition. Intra-annual variability is found to be highest in early autumn, linked to a combination of seasonal changes in radiation and phenological changes in canopy quantum yield. Inter-annual variability was low, with less than %5 variation from year to year, and factors driving this variability were not clearly apparent. Over the 5 years of reported measurements, this forest sequestered about 6 tonnes of C per hectare per annum. Photosynthetically active radiation use efficiency of the forest is about 4.2%. Constancy of radiation use efficiency was observed at both diel and annual scales. This constancy depended on the ecosystem''s thermal inertia and assimilation/radiation response curve characteristics at diel time scales but depended on thermal inertia and phenological changes in quantum yield at annual time scales. The net carbon uptake rates are consistent with two other flux sites in the British Isles and suggest that the relatively maritime climatology of these areas is highly suitable for the species of trees routinely planted here. [Copyright &y& Elsevier]

Carbon Capture and Storage (CCS) is an essential tool in the fight against climate change. Any prospective storage site must meet various criteria that ensure the effectiveness, safety and economic viability of the storage operations. Finding the most suitable site for the storage of the captured CO 2 is an essential part of the CCS chain of activity. This work addresses the site selection of a second site for the Acorn CCS project, a project designed to develop a scalable, full-chain CCS project in the North Sea (offshore northeast Scotland). This secondary site has been designed to serve as a backup and upscaling option for the Acorn Site, and has to satisfy pivotal project requirements such as low cost and high storage potential. The methodology followed included the filtering of 113 input sites from the UK CO 2 Stored database, according to general and project-specific criteria in a multi-staged approach. This criteria-driven workflow allowed for an early filtering out of the less suitable sites, followed by a more comprehensive comparison and ranking of the 15 most suitable sites. A due diligence assessment was conducted of the top six shortlisted sites to produce detailed assessment of their storage properties and suitability, including new geological interpretation and capacity calculations for each site. With the new knowledge generated during this process, a critical comparison of the sites led to selection of East Mey as the most suitable site, due to its outstanding storage characteristics and long-lasting hydrocarbon-production history, that ensure excellent data availability to risk-assess storage structures. A workshop session was held to present methods and results to independent stakeholders; feedback informed the final selection criteria. This paper provides an example of a criteria-driven approach to site selection that can be applied elsewhere. • CO 2 storage site selection for the Acorn CCS project in the North Sea. • Criteria-driven approach based on geological, economic, and safety aspects. • Multi-staged methodology including filtering, comparison and ranking of sites. • East Mey selected thanks to its storage characteristics and hydrocarbon history. [ABSTRACT FROM AUTHOR]

• Offshore CCS research & development making good progress in Scotland and wider UK. • Yet differing views between oil and gas developers and civil society on CCS. • Survey and interview research explores differences between stakeholders. • Respondents more familiar with CCS tend to see it as more necessary for mitigation. • CCS most likely to find stakeholder support for specific and/or localised uses. Although Scotland and the wider UK is making good progress with research and development towards deployment of offshore carbon capture and storage, there is increasing divergence in opinion on the necessity of CCS for meeting climate change targets. Oil and gas operators appear optimistic about the technical feasibility of CCS; whereas civil society and NGOs are increasingly vocal in their scepticism towards the necessity of CCS in a net-zero society. Given that operators' expertise may be required to support offshore CO 2 storage given their subsea experience, and that civil society is important in shaping government and public opinion, this divergence may be a challenge to offshore CCS deployment in the UK and elsewhere. The purpose of this paper is to evaluate the grounds on which oil and gas operators' views on CCS differ from a wider range of stakeholders, through a survey and in-depth interviews. Our results show that people with more knowledge of CCS are more likely to support its deployment, and that strong belief in anthropogenic climate change is lower – albeit rising – among oil and gas respondents. Our results also show concern that the net-zero transition may have negative effects for carbon-intensive regions, and that storage expertise is the UK's strongest skill set for CCS deployment. We suggest that across a range of stakeholders, the value of CCS is thus most likely to lie in specific applications (e.g. hydrogen) and/or very specific localities (e.g. places with existing subsurface knowledge and skills), rather than widespread deployment as a mitigation technology. [ABSTRACT FROM AUTHOR]

The future status of peatlands as carbon stores/sinks is uncertain given current and predicted environmental change. Several factors can affect the magnitude of the peatland carbon sink including disturbances such as wildfire. There is at present little evidence of how wildfire affects the emission of carbon dioxide (CO2) and methane (CH4) via perturbation to aerobic and anaerobic respiration. The greatest effects, which are likely to vary according to wildfire severity, would be expected in the immediate post-fire stages when little recovery has taken place. Here, we investigate five UK peatland wildfires (2011–2012) in the immediate post-wildfire period measuring CO2 and CH4 fluxes using static chambers. Fire severity was described using a modified form of the composite burn index. A hierarchical partitioning approach indicated time since fire was the most strongly associated variable that fluxes of both CO2, and CH4 followed by soil temperature for CO2 and fire severity for CH4. Using a liner mixed modelling approach to account for repeated measures; fire severity was a significant term for CH4 and borderline significant for CO2. Mean fluxes of CH4 were consistently lower on burnt sites. In contrast, data from a fire in the north of Scotland appeared to show the opposite relationship for CH4 with higher fluxes on the burnt sites. These results suggest that wildfire can affect gaseous carbon fluxes, but the responses can be variable in both space and time and that disruption to anaerobic processes may be site and/or fire dependent. [ABSTRACT FROM AUTHOR]

Yamulki and co-authors address in their recent publication the important issue of net emissions of greenhouse gases (GHGs) from peatlands where land use conversion has taken place. In their case, they studied conversion to forestry versus peatland restoration after a first rotation of plantation forestry. They monitored soil-derived fluxes of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) using opaque chamber measurements on planted and unplanted control treatments (with or without drainage), and an unplanted plot within a restored (felled) block on former lowland raised bog. They propose that their measurements of greenhouse gas (GHG) emissions at these sites suggest that the total net GHG emissions, in 100 yr carbon dioxide equivalents, of the restored peat bog would be higher than that of the peat bog with trees. We believe there are a number of issues with the measurement, calculation and comparison of these greenhouse budgets that may invalidate this conclusion. [ABSTRACT FROM AUTHOR]

The article presents the updates related to environmental law. The Energy Act seeks to implement the coalition government's Plan for Government and Carbon Plan to support Great Britain's low carbon, safe, and affordable energy infrastructure. The 2011 Water Environment Order in Scotland allows the Scottish Ministers and the Scottish Environment Protection Agency (SEPA) to practice their functions. Meanwhile, the 2011 Storage of Carbon Dioxide regulations are discussed.

Examples of the commercial trap Mosquito Magnet® Pro™ (MMP emitting attractant 1-octen-3-ol in carbon dioxide 500 mL/min generated from propane fuel), were run 24 h/day on the Isle of Skye, Scotland, during June–August 2001 and evaluated for catchingCulicoidesbiting midges (Diptera: Ceratopogonidae). From 30 days trapping, the catch averaged 2626 ± 1358Culicoidesfemales/trap/day (mean± SE, range 558 ± 139 to 6088 ± 3597, for five sets of six consecutive nights), predominantly the pestCulicoides impunctatusGoetghebuer (68% overall), plusC. vexans(Stæger) > C. deltaEdwards>C. pulicaris(L.) > C. lupicarisDowns&Kettle>C. albicans(Winnertz)>otherCulicoidesspp.Attempts were made to enhance the odour baiting system by adding hexane-extracts (2.1 mg/day) of hair samples from large host animals, resulting in the following effects onCulicoidescollections: sheep− 53 %, red deer− 26 %, calf+ 20%, pony+ 40%, water buffalo+ 262%, with greatest increases forC. impunctatus and C. pulicaris.Serial concentrations of these animal extracts (10−1 − 10−3 × 2.2 g/mL) were assayed on parous femaleC. impunctatusresponse in a Y-tube olfactometer (air-flow 150 mL/min), and by electroantennogram (EAG) onCulicoides nubeculosusMeigen laboratory-reared parous females. Positive behavioural responses to host odours were dose-dependent: the water buffalo extract being most active (threshold 0.22 g/mL), similar to deer, whereas other host extracts were≥ 10-fold less active. Correspondingly, the EAG threshold was lowest for water buffalo, 10-fold greater for deer, calf and pony, but not detected for sheep. If the active component(s) of these host extracts can be identified and synthesized, they might be employed to improve the capture ofCulicoidesmidges for local control by removal trapping. [ABSTRACT FROM AUTHOR]

The influence of CO2 transported in the transpiration stream on measurements of leaf photosynthesis and stem respiration was investigated. Measurements were made on trees in a temperate forest in Scotland and in a tropical rain forest in Cameroon, and on shrubs in the Sahelian zone in Niger. A chamber was designed to measure the CO2 partial pressure in the gas phase within the woody stems of trees. High CO2 partial pressures were found, ranging from 3000 to 9200 Pa. Henry's Law was used to estimate the CO2 concentration of xylem sap, assuming that it was in equilibrium with the measured gas phase partial pressures. The transport of CO2 in the xylem sap was calculated by multiplying sap CO2 concentration by transpiration rate. The magnitude of aqueous transport in the studied species ranged from 0.03 to 0.35 μmol CO2 m−2 s−1, representing 0.5 to 7.1% of typical leaf photosynthetic rates. These values strongly depend on sap pH. To examine the influence of aqueous transport of CO2 on stem gas exchange, we made simultaneous measurements of stem CO2 efflux and sap flow on the same stem. After removing the effect of temperature, stem CO2 efflux was positively related to sap flow. The apparent effect on measurements of stem respiration was up to 0.7 μmol m−2 s−1, representing ∼12% of peak stem respiration rates. [ABSTRACT FROM PUBLISHER]

The acid-base status of two sea urchins, Psammechinus miliaris (Gmelin) and Echinus esculentus (L.) during experimental emersion has been investigated. Sea urchins were collected from the Firth of Clyde between August and September 1987. The carbon dioxide capacity of the coelomic fluid of P. miliaris was greater than that of E. esculentus, although both were low and only marginally greater than that of sea water. The pH of the coelonic fluid was also low (7.05 to 7.17) and was influenced mainly by the internal partial pressure of CO (P). Acid-base disturbance in the coelomic fluid of both species during emersion, although minimal, was more pronounced in E. esculentus than in P. miliaris and was due primarily to an increase in the internal P, although there was an increase in the concentration of L-lactate in the coelomic fluid of E. esculentus. The coelomic fluid of both species was in a state of perfectly compensated respiratory acidosis. An increase in the concentration of divalent ions (Ca and Mg) may be related to the dissolution of the test as a source of carbonate buffer. [ABSTRACT FROM AUTHOR]

In a 27-month CO2-enrichment experiment, Calluna vulgaris plants were grown on peat obtained from an upland heath in NE Scotland and given a nutrient supply which mimicked that in precipitation in the area. Three CO2 concentrations were used; ambient, +100 ppm and + 200 ppm. Calluna showed a negative growth response to increased CO2 over the first year of treatment and a positive response by the end of the experiment. Final above-ground biomass was greatest in the enriched CO2 treatments, showing an increase of 30% in + 100 ppm CO2. Determination of tissue nutrient concentration, and calculation of total nutrient uptake, demonstrated that nutrient uptake did not increase with increased growth, resulting in significant dilution of elements in leaf tissue. This suggests that, in its typical, nutrient poor habitats, the growth response of Calluna to CO2 will be limited by nutrient deficiency, and will reach a maximum with a relatively small increase in CO2 concentration. Flowering was advanced and extremely prolific in +100 ppm CO2 grown plants, but the ecological significance of this is uncertain. The results highlight the need for long term studies of native species on their natural soils, using lower CO2 concentrations than the usual 'double CO2'. [ABSTRACT FROM AUTHOR]