Southern Pennines Research Articles

The palynostratigraphy of the Brassington Formation (Upper Miocene) of the southern Pennines, central England

The Brassington Formation of Derbyshire and Staffordshire in the southern Pennine hills of central England is a succession of sands, gravels and clays preserved within karstic cavities in Carboniferous Limestone. Varicoloured clays and a thin lignite within the uppermost unit (the Kenslow Member) at Kenslow Top Pit near Friden, Derbyshire has yielded abundant pollen, spores and plant remains. The palynoflora was previously assigned to the Late Miocene to Early Pliocene. The Brassington Formation is reinterpreted here as being Tortonian (Late Miocene) in age based onthe presence of the key pollen taxa Symplocosroman Tricolpopollenites liblarensis and Tricolpopollenites microhenrici. The Tortonian age of the Brassington Formation means that it is the most extensive well-dated onshore Miocene unit in the UK. This refined age assessment also indicates that the rate of continuous uplift of the southern Pennines during Alpine mountain building was 0.03–0.06 mm a–1; this is significantly lower than has been recently suggested. Using the coexistence approach on the Kenslow Member palynofloras, a median value for the mean annual temperature is about 16°C.

Carbonaceous aerosols contributed by traffic and solid fuel burning at a polluted rural site in Northwestern England

Abstract. The experiment presented in this paper was conducted at the Holme Moss site, which is located in the southern Pennines region in Northwestern England during November–December 2006. The strong southwesterly wind during the experimental period, which enhanced the transport of urban pollutants from the conurbations of Greater Manchester and Liverpool, in addition to the seasonally increased nearby residential heating activities, made this site a receptor for pollutants from a range of sources. A factor analysis is applied to the mass spectra of organic matter (OM) measured by the Aerodyne Aerosol Mass Spectrometer (AMS) to attribute the pollutant sources. Besides the oxygenated organic aerosol (OOA), this site was found to contain a considerable fraction of primary organic aerosols (POA, mass fraction 50–70% within total mass of OM). The POA sources are attributed to be traffic emission and solid fuel burning, which are identified as hydrocarbon-like organic aerosol (HOA) and solid fuel organic aerosol (SFOA) respectively. There were strongly combined emissions of black carbon (BC) particles from both sources. The refractory BC component (rBC) was characterized by a single particle soot photometer. This site began to be influenced during the late morning by fresh traffic emissions, whereas solid fuel burning became dominant from late afternoon until night. A covariance analysis of rBC and POA was used to derive source specific emission factors of 1.61 μgHOA/μgrBC and 1.96 μgHOA/μgrBC. The absorbing properties of aerosols were characterized at multiple wavelengths (λ), and a stronger spectral dependence of absorption was observed when this site was significantly influenced by solid fuel burning. The rBC was estimated to contribute 3–16% of submicron aerosol mass. The single scattering albedo at λ = 700 nm (SSA700 nm) was significantly anti-correlated with the rBC mass fraction, but also associated with the BC mixing state. The BC incorporation/removal process therefore may play a role in modulating the radiative properties of aerosols at the site under the influence of fresh sources. Given that traffic and residential combustion of solid fuels are significant contributors of carbonaceous aerosols over Europe, these results provide important source-specific information on modeling the anthropogenic carbonaceous aerosols.

Impact of gully erosion on carbon sequestration in blanket peatlands

CR Climate Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials CR 45:31-41 (2010) - DOI: https://doi.org/10.3354/cr00887 Impact of gully erosion on carbon sequestration in blanket peatlands Martin Evans1,*, John Lindsay2 1Upland Environments Research Unit, School of Environment and Development, University of Manchester, Manchester M19 3PL, UK 2Department of Geography, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada *Email: martin.evans@manchester.ac.uk ABSTRACT: Over 50% of UK soil carbon is stored in peatland systems and 75% of these peatlands are upland blanket bog. The upland blanket bogs of the UK have suffered severe erosion over the last millennium so that they are widely dissected by gully systems. Gully erosion entails primary removal of particulate carbon from the peatland system but also has secondary effects in that it enhances drainage and lowers water tables, potentially enhancing decomposition of surface peats. This paper exploits recent high resolution mapping of the gully erosion on the Bleaklow Plateau in the southern Pennines and existing data on peat growth rates in the area to assess the impact of gully erosion on peatland carbon balance and the relative importance of primary and secondary impacts of gullying on carbon sequestration. The results indicate that gully erosion during the last millennium has shifted the Bleaklow Plateau from being a net sink of carbon (–20.3 gC m–2 yr–1) to a net source (29.4 gC m–2 yr–1). The relative importance of gullying impacts can be expressed as follows: particulate organic carbon (POC) flux > change in gully net ecosystem exchange >> loss of gully margin carbon sequestration. The implication of these findings is that the magnitude of the potentially reversible impacts of gully erosion (reduced carbon fixation due to vegetation loss and ongoing erosional loss of POC) far exceed the effects associated with irreversible morphological change (enhanced peat decomposition in gully margin locations). KEY WORDS: Blanket peat · Gully erosion · Carbon balance · Carbon sequestration Full text in pdf format PreviousNextCite this article as: Evans M, Lindsay J (2010) Impact of gully erosion on carbon sequestration in blanket peatlands. Clim Res 45:31-41. https://doi.org/10.3354/cr00887 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in CR Vol. 45. Online publication date: December 30, 2010 Print ISSN: 0936-577X; Online ISSN: 1616-1572 Copyright © 2010 Inter-Research.

Fluvial organic carbon flux from an eroding peatland catchment, southern Pennines, UK

Abstract. This study investigates for the first time the relative importance of dissolved organic carbon (DOC) and particulate organic carbon (POC) in the fluvial carbon flux from an actively eroding peatland catchment in the southern Pennines, UK. Event scale variability in DOC and POC was examined and the annual flux of fluvial organic carbon was estimated for the catchment. At the event scale, both DOC and POC were found to increase with discharge, with event based POC export accounting for 95% of flux in only 8% of the time. On an annual cycle, exports of 35.14 t organic carbon (OC) are estimated from the catchment, which represents an areal value of 92.47 g C m−2 a−1. POC was the most significant form of organic carbon export, accounting for 80% of the estimated flux. This suggests that more research is required on both the fate of POC and the rates of POC export in eroding peatland catchments.

Peat soils as a source of lead contamination to upland fluvial systems

Upland peat soils are generally regarded as effective sinks of atmospherically deposited lead. However, the physical process of erosion has the potential to transform peat soils from sinks to sources of lead contamination. Lead input and fluvial lead outputs (dissolved + particulate) were estimated for a contaminated and severely eroding peatland catchment in the southern Pennines, UK. Lead input to the catchment is 30.0 ± 6.0 g ha −1 a −1 and the output from the catchment is 317 ± 22.4 g ha −1 a −1. Suspended particulate matter accounts for 85% of lead export. Contaminated peat soils of the catchment are a significant source of lead to the fluvial system. This study has demonstrated strong coupling between the physical process of erosion and the mobilization of lead into the fluvial system. The process of peat erosion should therefore be considered when estimating lead outputs from peatland catchments, especially in the context of climate change.

Microbial Communities in Long-Term Heavy Metal Contaminated Ombrotrophic Peats

High concentrations of heavy metals are known to be toxic to many soil organisms. The effects of long-term exposure to lower levels of metals on the soil microbial community are, however, less well understood. The southern Pennines of the U.K. are characterised by expanses of ombrotrophic peat soils that have experienced deposition of high levels of heavy metals since the mid to late 1800s. Concentrations of metals in the peat remain high but the effect of the contamination on the in-situ microbial communities is unknown. Geochemical and molecular polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and sequencing techniques were used to derive new information on the metal chemistry and microbial populations in peat soils from six locations in the southern Pennines. All sites were highly acidic (pH 3.00–3.14) with high concentrations of potentially toxic heavy metals, particularly porewater Zn and particulate-associated Pb. The results also reveal a split in site characteristics between the most polluted sites with the highest levels of bioavailable metals (Bleaklow, FeatherBed Moss and White Hill) and those with much lower bioavailable metals (Cowms Moor, Holme Moss and Round Hill). There was no difference in the number of dominant bacterial species between the sites but there were significant differences in the species composition. At the three sites with the highest levels of bioavailable metals, bacterial species with a high similarity to acidophilic sulphur- and iron-oxidizing bacteria and those from high metal environments were detected. The transformations carried out by these metal mobilising and acid producing bacteria may make heavy metals more bioavailable and therefore more toxic to higher organisms. Bacteria with similarity to those typically found in forest and grassland soils were documented at the three sites with the lowest levels of bioavailable metals. The data highlight the need for further studies to elucidate the species diversity and functionality of bacteria in heavy metal contaminated peats in order to assess implications for moorland restoration.

The role of wildfire and gully erosion in particulate Pb export from contaminated peatland catchments in the southern Pennines, U.K.

The near-surface layer of peatlands of the Peak District, southern Pennines, UK, is severely contaminated with atmospherically deposited Pb. Contemporary catchment soil Pb inventories at Upper North Grain and Torside Clough reveal that ∼ 23% and ∼ 54%, respectively, of the potential store of Pb in each catchment has been lost through erosion of the contaminated near-surface peat layer. Soil Pb inventories and the Pb content of suspended sediments reveal that, in both catchments, the main mechanism for contemporary particulate Pb export is gully erosion. Historical sheet erosion on bare peat flats at Torside Clough has released significant quantities of Pb into the fluvial system, triggered by the exposure of the near-surface peat during an accidental wildfire in 1970. Up to 32% of the total Pb export from the catchment may have been released during a discrete erosion event soon after the wildfire. Accidental wildfires and the subsequent release of highly contaminated peat into the southern Pennine fluvial system may increase under predicted climate change scenarios.

Lead contamination of fluvial sediments in an eroding blanket peat catchment

Over the last few years there has been growing concern over the mobilisation of anthropogenically derived, atmospherically deposited Pb from upland blanket peat soils to receiving surface waters. The near-surface layer of blanket peat soils of the Peak District, southern Pennines, UK, is severely contaminated with high concentrations of Pb. Erosion of peat soils in this upland area may be releasing large quantities of previously deposited Pb into the fluvial system. Samples of fluvial sediments (suspended, floodplain, streamside fan, trash-line and channel bed) were collected from a severely eroding blanket peat catchment in the Peak District in order to investigate Pb contamination of fluvial sediments, to determine the mechanism for fluvial Pb transport and to determine if erosion of contaminated peat soils in the catchment is releasing Pb into the fluvial system. Concentrations of Pb associated with fluvial sediments are considerably higher than those in the catchment geology, but not as high as those in peat soils in the catchment. Intra- and inter-storm variability in the Pb content of suspended sediments can be explained by differences in organic matter content of these sediments and differences in erosion processes operating within the catchment. High Pb concentrations are associated with suspended sediments that have a high organic matter content. The results of this study suggest that organic matter is the principle vector for sediment-associated Pb in the fluvial system. Erosion of contaminated peat soils in the Peak District is releasing Pb into the fluvial system. The extent to which this is a problem in other peatland environments is an area requiring further research.

Sediment–Water Interactions in an Eroded and Heavy Metal Contaminated Peatland Catchment, Southern Pennines, UK

Atmospherically deposited lead in the upper layer of the heavily eroded peatlands of the Peak District, southern Pennines, UK, reaches concentrations in excess of 1,000 mg kg−1. Erosion of the upper peat layer in this region is releasing lead, associated with eroded peat particles, into the fluvial system. Understanding the process mechanisms that control dissolved lead concentrations in contaminated peatland streams is vital for understanding lead cycling and transport in peatland streams. Many headwater streams of the southern Pennines recharge drinking water reservoirs. Measurements in the Upper North Grain (UNG) study catchment show that mean sediment-associated and dissolved lead concentrations are 102±39.4 mg kg−1 and 5.73±2.16 µg l−1, respectively. Experimental evidence demonstrates that lead can desorb from suspended sediments, composed of contaminated peat, into stream waters. In-stream processing could therefore account for the elevated dissolved lead concentrations in the fluvial system of UNG.

Scale-dependent spatial variability in peatland lead pollution in the southern Pennines, UK

Increasingly, within-site and regional comparisons of peatland lead pollution have been undertaken using the inventory approach. The peatlands of the Peak District, southern Pennines, UK, have received significant atmospheric inputs of lead over the last few hundred years. A multi-core study at three peatland sites in the Peak District demonstrates significant within-site spatial variability in industrial lead pollution. Stochastic simulations reveal that 15 peat cores are required to calculate reliable lead inventories at the within-site and within-region scale for this highly polluted area of the southern Pennines. Within-site variability in lead pollution is dominant at the within-region scale. The study demonstrates that significant errors may be associated with peatland lead inventories at sites where only a single peat core has been used to calculate an inventory. Meaningful comparisons of lead inventories at the regional or global scale can only be made if the within-site variability of lead pollution has been quantified reliably.

Working with Tradition: Towards a Partnership Model of Fieldwork

This paper explores the interaction between fieldworker and “tradition bearer” over an extended period of time, in the context of an ethnographic study of singing traditions in the southern Pennines of England. Using examples, it examines the negative as well as the positive aspects of the exchange, with particular emphasis on mutuality and reciprocity. It charts the development of key relationships and the ways in which they have come to maturity and achieved equilibrium. Careful thought is given to the role of the fieldworker in respect of active/passive, interventionist/non-interventionist stances. Aspects of performance, commercialisation, networking, promotion, and media relations are discussed. Following a consideration of ethical and moral issues, including exploitation and advocacy, the paper suggests a working model of partnership as a way forward for future productive field-based research into traditional expressive arts.

Eroding blanket peat catchments: Global and local implications of upland organic sediment budgets

Globally, peatlands account for circa 50% of terrestrial carbon storage containing as much carbon as is present in the atmosphere. The uplands of the UK have an extensive cover of blanket peat but much of it is actively eroding. This paper presents a detailed organic sediment budget for a blanket peat catchment in the north Pennines and comparative data from a catchment in the southern Pennines. The catchments have total sediment yields (organic and mineral) of 44 and 267 t km − 2 a − 1 and organic sediment yields 31 and 195 t km − 2 a − 1 , respectively. They represent two extremes of a spectrum of eroded peat catchments. It is demonstrated that the lower sediment yields in the north Pennines are associated with extensive natural revegetation of the catchment and consequent reductions in slope-channel linkage. Construction of a carbon budget for the north Pennine catchment demonstrates that particulate carbon losses associated with the fluvial suspended sediment load are the largest single carbon loss from the system. The system is currently close to carbon neutral but much higher carbon losses associated with actively eroding systems such as the south Pennine site would make these systems a major carbon source. The possibility that enhanced summer temperatures and winter storminess will accelerate erosion of upland mires means there is a risk that physical degradation of peatlands could become a significant positive feedback on global warming. Mitigation of these potential global effects will depend on local management informed by a clear understanding of peatland sediment dynamics. The sediment budget data here suggest that in gullied peatlands revegetation of gully floors is an effective control on sediment flux so that techniques such as gully blocking are likely to be effective approaches to erosion control.

How important is N 2O production in removing atmospherically deposited nitrogen from UK moorland catchments?

Nitrate (NO 3 −) leaching due to anthropogenic nitrogen (N) deposition is an environmental problem in many parts of the UK uplands, associated with surface water acidification and affecting lake nutrient balances. It is often assumed that gaseous return of deposited N to the atmosphere as N 2O through denitrification may provide an important sink for N. This assumption was tested for four moorland catchments (Allt a’Mharcaidh in the Cairngorms, Afon Gwy in mid-Wales, Scoat Tarn in the English Lake District and River Etherow in the southern Pennines), covering gradients of atmospheric N deposition and surface water NO 3 − leaching, through a combination of field and laboratory experiments. Field measurements of N 2O fluxes from static chambers with and without additions of NH 4NO 3 solution were carried out every 4 weeks over 1 yr. Wetted soil cores from the same field plots were used in experimental laboratory incubations at 5 and 15 °C with and without additions of NH 4NO 3 solution, followed by measurement of N 2O fluxes. Field measurements showed that significant N 2O fluxes occurred in only a very small number of plots with most showing zero values for much of the year. The maximum fluxes were 0.24 kg-N/ha/yr from unamended plots at the River Etherow and 0.49 kg-N/ha/yr from plots with NH 4NO 3 additions at the Allt a’Mharcaidh. Laboratory incubation experiments demonstrated that large N 2O fluxes could be induced by warming and NH 4NO 3 additions, with the top 5 cm of soil cores responsible for the largest fluxes, reaching 11.8 kg-N/ha/yr from a podsol at Scoat Tarn. Acetylene block experiments showed that while N 2 was not likely to be a significant denitrification product in these soils, reduced N 2O fluxes indicated that nitrification was an important source of N 2O in many cases. A simple model of denitrification suggesting that 10–80% of net N inputs may be denitrified from non-agricultural soils was found to greatly over-estimate fluxes in the UK uplands. The proportion of deposition denitrified was found to be much closer to the IPCC suggested value of 1% with an upper limit of 10%. Interception of N deposition by vegetation may greatly reduce the net supply of N from this source, while soil acidification or other factors limiting carbon supply to soil microbes may prevent large denitrification fluxes even where NO 3 − supply is not limiting.

Sediment Stratigraphy and Heavy Metal Fluxes to Reservoirs in the Southern Pennine Uplands, UK

Reservoir sediments are rarely used as environmental archives because of the potential for sediment disturbance by fluctuating water levels. However, rapid rates of sedimentation, proximity to urban centres and often the existence of management records, may make them potentially important resources for reconstructing recent, anthropogenically-derived environmental change. This project assesses the potential of reservoir sedimentary records for reconstructing past atmospheric and drainage basin fluxes of heavy metals (manganese, iron, nickel, copper, zinc and lead) in the southern Pennines, UK. Five reservoirs were selected on the basis of management history and drainage basin characteristics. Multi-parameter analysis showed sediments to be replicable across the ȁ8accumulating zone’ with reasonably consistent rates of sedimentation. Water level fluctuations were not found to detrimentally affect sediment records in the deepwater area of the reservoirs. In fact, spheroidal carbonaceous particle (SCP) profiles show trends in inputs that closely reflect major changes in industrialisation, indicating the reservoir sediments to be excellent records of particulate inputs. Only lead (Pb) and zinc (Zn) were significantly enriched in the reservoir sediment in comparison to background levels. Manganese (Mn), iron (Fe) and to a limited degree, copper (Cu), appeared to be affected by post-deposition mobility. Preliminary calculations of Pb fluxes indicate that over 80% of the current Pb input to the reservoirs is from Pb deposited onto drainage basin soils in the past, rather than from direct atmospheric deposition or natural background inputs. In Howden reservoir, for example, the total Pb flux to deepwater sediment cores in 2000 was 119 mg m−2 a−1. Of this, an estimated 99 mg m−2 a−1 was from anthropogenically-derived Pb, initially deposited onto drainage basin soils and subsequently entering the reservoir via erosion and leaching processes. There is, therefore, no indication that the flux of Pb to the aquatic system is declining in response to reductions in Pb deposition. The ecotoxicological effects of the high and continuing Pb flux to these reservoirs, despite recent decreases in atmospheric deposition, is an area requiring further investigation.

Effects of simulated long‐term climatic change on the bryophytes of a limestone grassland community

AbstractThe bryophyte vegetation of upland limestone grassland at Buxton in the southern Pennine Hills (UK) was studied following seven years' continuous simulated climate change treatments. The experimental design involved two temperature regimes (ambient, winter warming by 3°C) in factorial combination with three moisture regimes (normal, summer drought, supplemented summer rainfall) and with five replicate blocks. Percentage cover of the bryophytes was estimated visually using 15 randomly positioned quadrats (30 cm × 30 cm) within each of the 30 3 m × 3 m plots. Significant treatment effects were found but these were relatively modest. Total bryophyte cover and cover of Calliergonella cuspidata and Rhytidiadelphus squarrosus responded negatively to drought, whereas Fissidens dubius increased in the droughted plots. Campyliadelphus chrysophyllus increased with winter warming, while R. squarrosus, Lophocolea bidentata and species richness all decreased. The effects on the total bryophyte flora were further studied by canonical correspondence analysis, which yielded a first axis reflecting the combined effects of the moisture and temperature treatments. However, this analysis and a detrended correspondence analysis of the plot data also revealed that natural factors were more important causes of variation in the grassland community than the simulated climate treatments. It was concluded that dewfall may be an important source of moisture for grassland bryophytes and that this factor may have reduced the impact of the moisture treatments. The absence of some thermophilous species such as Homalothecium lutescens in the plots initially may also have reduced their scope for major vegetational change.

Heavy metal release by peat erosion in the Peak District, southern Pennines, UK

AbstractUpper North Grain (UNG) is a heavily eroding blanket peat catchment in the Peak District, southern Pennines, UK. Concentrations of lead in the near‐surface peat layer at UNG are in excess of 1000 mg kg−1. For peatland environments, these lead concentrations are some of the highest globally. High concentrations of industrially derived, atmospherically transported magnetic spherules are also stored in the near‐surface peat layer. Samples of suspended sediment taken during a storm event that occurred on 1 November 2002 at UNG, and of the potential catchment sources for suspended sediments, were analysed for lead content and the environmental magnetic properties of anhysteretic remanent magnetization (ARM) and saturation isothermal remanent magnetization (SIRM). At the beginning of the storm event, there is a peak in both suspended sediment and associated lead concentration. SIRM/ARM values for suspended sediment samples throughout the storm reveal that the initial ‘lead flush’ is associated with a specific sediment source, namely that of organic sediment eroded from the upper peat layer. Using the magnetic ‘fingerprinting’ approach to discrimination of sediment sources, this study reveals that erosion of the upper peat layer at UNG is releasing high concentrations of industrially derived lead (and, by inference, other toxic heavy metals associated with industrial particulates) into the fluvial systems of the southern Pennines. Climate‐change scenarios for the UK, involving higher summer temperatures and stormier winters, may result in an increased flux both of sediment‐associated and dissolved heavy metals from eroding peatland catchments in the southern Pennines, adversely affecting the quality of sediment and water entering reservoirs of the region. Copyright © 2005 John Wiley & Sons, Ltd.

Blanket peat erosion and sediment yield in an upland reservoir catchment in the southern Pennines, UK

AbstractThis paper investigates temporal variations in fluxes of peat and other sediment in the catchment of March Haigh Reservoir, West Yorkshire. Long‐term estimates of sediment yield were derived from a study of reservoir sediments. Magnetic properties were used to correlate ten cores to a master profile dated using 210Pb and 137Cs. A 14C date suggests that most of the organic component of the sediment is allochthonous and derived from peat eroded from the catchment. Organic sediment yields suggest low catchment erosion rates between 1838 and 1963. Blanket peat erosion increased significantly after 1963, and peaked between 1976 and 1984. Estimates of total sediment yield range between 2 and 28 t km−2 a−1. These yields are significantly lower than those from some previous studies examining reservoir sedimentation in other blanket peat‐covered catchments. The low yield estimates may be due to relatively low rates of erosion in the basin, but may also be partly explained by maintenance of silt traps during the early life of the reservoir and removal of sediment by scouring. Sedimentation within the reservoir is spatially variable, and bathymetry and sediment source appear to be the dominant controls on sedimentation patterns within the reservoir. Copyright © 2005 John Wiley & Sons, Ltd.

Recreating atmospheric sulphur deposition histories from peat stratigraphy: Diagenetic conditions required for signal preservation and reconstruction of past sulphur deposition in the Derbyshire Peak District, UK

Three modern pristine and one previously polluted ombrotrophic peat were sampled and analysed to investigate whether the isotopic composition of atmospheric sulphur inputs could be preserved in the organic fraction of ombrotrophic peats without undue alteration through syn-depositional or diagenetic effects. Peat type (reflecting the environment of deposition and diagenesis) was shown to be critical in determining whether an environmental archive of sulphur deposition could be preserved within the profile. Of the pristine peats sampled, hummock peat from Shetland proved to be the most suitable exhibiting a near-constant δ 34S characteristic of the growing vegetation in the organic fraction of peat in the upper 30 cm of the profile. However, only short to medium term changes (<600 years) in input are likely to be preserved due to the masking effect produced by incorporation of sulphide, derived from bacterial sulphate reduction (BSR), into the organic fraction at depth. The organic fraction of peat sampled from waterlogged pools at Forsinard (NE Scotland) was masked by sulphide incorporation throughout the profile, while peat from Abisko (N. Sweden) was exposed to annual freeze–thaw cycles, which appear to have produced significant decomposition of the organically bound sulphur and loss of the original depositional isotopic signal. Three peat types were sampled from the southern Pennines, an area with a gross history of sulphur pollution during the Industrial Revolution: high hummock peat, low hummock peat and waterlogged peat from a pool complex. In drier, high and low hummock peat types, diagenesis and decomposition were not found to be significant processes in the upper portions of the peat. Hence, alterations in the isotopic composition of the organic sulphur fraction in the profile reflect that of the depositional environment. In the hummock peats, organically bound sulphur becomes isotopically lighter at around 1400 AD, which may reflect alterations in local sulphur inputs at this time due to the small-scale smelting of lead in the area. Isotopic compositions become progressively lighter still towards the peat surface layers, which correlate well with the excesses of sulphur deposition, largely from coal burning, during the Industrial Revolution.

Potentially toxic metals in ombrotrophic peat along a 400 km English–Scottish transect

Four samples of ombrotrophic peat were collected from each of 10 upland locations in a transect from the southern Pennines to the Highland Boundary Fault, a total distance of ca. 400 km. Bulk compositions and other properties were determined. Total contents of Al and heavy metals (Ni, Cu, Zn, Cd, Pb) were determined following digestion with hydrofluoric acid, and concentrations of metals extractable with dilute nitric acid were also measured. Supernatants obtained from aqueous extractions of the peat samples were analysed for pH, major cations and anions, dissolved organic carbon and dissolved metals, and concentrations of free metal ions (Al 3+, Ni 2+, etc.) were estimated by applying a chemical speciation model. Both total and HNO 3-extractable metal concentrations varied along the transect, the highest values being found at locations close to industrial and former mining areas. The HNO 3-extractable soil metal contents of Ni, Cu and Cd were appreciably lower than lowest-observed-effect-concentrations (LOEC) for toxicity towards microorganisms in acid, organic rich soils. However, the contents of Zn at two locations, and of Pb at five locations exceeded LOECs, suggesting that they may be exerting toxic effects in the peats. Soil solution concentrations of free heavy metal ions (Cu 2+, Zn 2+, Cd 2+, Pb 2+) were substantially lower than LOECs for toxicity towards vascular plants, whereas concentrations of Al 3+ were near to toxic levels at two locations.

Alan Charles Higgins (1936–2004)

Abstract. Alan Higgins was born in Hanley, Staffordshire on 16 December 1936, the youngest of three children. Throughout his childhood he was fascinated by the natural history of the nearby Peak District and it was not surprising that sciences played an important part in his education at Hanley High School. In 1955, he went to the University of Sheffield to study Geology and obtained a 2(1) degree in 1958. During those early years in Sheffield, he came under the influence of the late Professor Leslie Moore and, on graduation, was encouraged by him to undertake research on Namurian conodonts. At that time, little was known of the true potential of conodonts and, indeed, almost nothing of their occurrence in Upper Carboniferous rocks. Alan collected samples extensively throughout the southern Pennine region, often working closely with the staff of the Geological Survey and generated the first Namurian conodont zonation for the British Isles. He exploited every opportunity to prove the value of conodont studies outside the Carboniferous Period and, in 1962, published the results of an investigation on the microfaunas found in the Durness Limestone of northwest Scotland. His PhD was completed in 1961.In late 1961, he was awarded a DSIR (Government) Fellowship which allowed him to work in Brussels at the offices of the Belgian Geological Survey whilst investigating the stratigraphic distribution of conodonts in the Namurian type sections of the Namur Basin. These studies, carried out in close collaboration with Jos Bouckaert, established detailed correlations with the British sequences . . .