Southern Pennines Research Articles

Effects of pipe outlet blocking on hydrological functioning in a degraded blanket peatland

AbstractPeatland restoration practitioners are keen to understand the role of drainage via natural soil pipes, especially where erosion has released large quantities of fluvial carbon in stream waters. However, little is known about pipe‐to‐stream connectivity and whether blocking methods used to impede flow in open ditch networks and gullies also work on pipe networks. Two streams in a heavily degraded blanket bog (southern Pennines, UK) were used to assess whether impeding drainage from pipe networks alters the streamflow responses to storm events, and how such intervention affects the hydrological functioning of the pipe network and the surrounding peat. Pipeflow was impeded in half of the pipe outlets in one stream, either by inserting a plug‐like structure in the pipe‐end or by the insertion of a vertical screen at the pipe outlet perpendicular to the direction of the predicted pipe course. Statistical response variable η2 showed the overall effects of pipe outlet blocking on stream responses were small with η2 = 0.022 for total storm runoff, η2 = 0.097 for peak discharge, η2 = 0.014 for peak lag, and η2 = 0.207 for response index. Both trialled blocking methods either led to new pipe outlets appearing or seepage occurring around blocks within 90 days of blocking. Discharge from four individual pipe outlets was monitored for 17 months before blocking and contributed 11.3% of streamflow. Pipe outlets on streambanks with headward retreat produced significantly larger peak flows and storm contributions to streamflow compared to pipe outlets that issued onto straight streambank sections. We found a distinctive distance‐decay effect of the water table around pipe outlets, with deeper water tables around pipe outlets that issued onto straight streambanks sections. We suggest that impeding pipeflow at pipe outlets would exacerbate pipe development in the gully edge zone, and propose that future pipe blocking efforts in peatlands prioritize increasing the residence time of pipe water by forming surface storage higher up the pipe network.

Quantitative palynological analysis of the E2a and E2b goniatite biozones (Arnsbergian, Mississippian) in mudstones from the Southern Pennine Basin (U.K.)

We performed a quantitative palynological analysis of Arnsbergian (Namurian, Late Mississippian) mudstone intervals, potentially prospective for unconventional hydrocarbons. While many palynological studies exist on these stratigraphic intervals in the Widmerpool Gulf and the Edale Basin (sub-basins of the Pennine Basin), very few studies perform full statistical analyses. Using the Carsington Dam Reconstruction C3 (Carsington DRC3, Widmerpool Gulf) and the Karenight-1 (Edale Basin) boreholes, we show that the combination of quantitative palynological data and detrended correspondence analysis (DCA) can aid biozonation and additionally, provide paleoecological constraints to the Arnsbergian mudrocks. The studied interval in Carsington DRC3 was assigned to the TK miospore biozone and a hitherto undescribed peak in the fresh water alga Botryococcus was recorded. Using relative abundances of hinterland species, mainly from the genus Florinites, both boreholes could be correlated and a more confident assignment of the TK miospore biozone covering an interval containing goniatite biozone E2b in Karenight-1 was achieved. The techniques used in the current study should be especially valuable for assessing borehole materials where the recovery of macrofossils, like goniatites used as the main biostratigraphic tool in the Namurian, can be very low. Future studies should focus on the same stratigraphic interval from different sub-basins of the Pennine Basin to further assess the applicability of quantitative palynological analysis combined with DCA as a stratigraphic tool for potentially prospective mudstones.

On the distinction of pollen grains of early varieties of Hordeum from Glyceria species: addressing the early cereal cultivation problem in palynology

Pollen grains of primitive varieties of Hordeum vulgare collected by the Gene Bank of the Crop Research Institute, Prague, are compared to pollen of native Glyceria species of the United Kingdom with a view to establishing separation criteria. It is found that a separation of Hordeum vulgare from both Glyceria maxima and Glyceria fluitans is possible according to annular characteristics in combination with grain size as dependent variables. These findings have implications for the identification of cereal-type pollen grains that could be evidence for early cultivation in the Terminal Mesolithic of north-west Europe, and for the use of palynology as a reliable source of palaeobotanical data, particularly in its inland areas. A phase of vegetation disturbance from the pollen site of Dog Hill in the southern Pennine uplands of the UK, an area with a high density of ‘rod’ microlith flint sites, is introduced as a case example using the above protocol. Here, multiple Hordeum-type grains are encountered alongside prominent pollen indicators of disturbance, but also including non-pollen palynomorphs and microcharcoal data, at a date well before the mid-Holocene decline in Ulmus pollen frequencies that is often regarded as marking the beginning of the Neolithic. Confident identification of cereal-type pollen will greatly assist the understanding of the introduction of cultivation and the Mesolithic–Neolithic transition in north-west Europe. The objective of this study is to show the utility of this palynology with respect to defining the ecology of early cultivation in UK uplands.

Regional variations in fluid formation and metal sources in MVT mineralization in the Pennine Orefield, UK: Implications from rare earth element and yttrium distribution, Sr-Nd isotopes and fluid inclusion compositions of hydrothermal vein fluorites

The Pennine Orefield is one of the most important ore fields for Pb-Zn-Ba-F mineralization in Great Britain. It is subdivided into the Northern Pennine Orefield (NPO), consisting of the Alston and Askrigg Blocks, and the Southern Pennine Orefield (SPO). The Alston Block is underlain by the early Devonian Weardale Granite and the Askrigg Block by the coeval Wensleydale Granite. The potential relationship between the batholiths and the mineralization is a matter of debate. We here studied the rare earth elements and Y (REY) geochemistry, Sr-Nd isotopes and fluid inclusion (FI) compositions of fluorites from the two structural blocks in the NPO and found that the fluorite mineralization in these blocks differ substantially. The REY in Askrigg fluorites show features that are characteristic for leaching of adjacent Lower Carboniferous limestones. In contrast, Alston fluorites have significantly higher REY concentrations, lack REYSN limestone signatures and show a decoupling of redox-sensitive Eu from its trivalent REY ‘neighbours’. Neodymium isotopes indicate a similar crustal source of REY in both blocks, but higher REY concentrations and lower Y/Ho ratios suggest Lower Carboniferous shales as potential REY source in the Alston Block. The fluids that precipitated the Alston fluorites experienced temperatures > 250 °C prior to mineral formation, as evidenced by Eu geothermometry. Fluorite formation, however, occurred at much lower temperatures, as suggested by homogenization temperatures in FI, that fall within ranges of 105–159 °C in Alston and 99–160 °C in Askrigg fluorites. Mineralization of the Mississippi-Valley Type usually lack association with igneous activity. We show that some of the fluids responsible for the NPO mineralization were influenced by magmatic sources. The REY systematics in Alston fluorites may be linked to an interaction of the Permian-age Whin Sill dolerite with the basement granite, which heated fluids and focussed fluid flow into the overlying sedimentary rocks. In the Askrigg Block, where such a dolerite intrusion was not described, fluorites lack any positive EuSN anomalies, indicating that these fluids had never been subjected to temperatures exceeding 200–250 °C.

Total organic carbon in the Bowland-Hodder Unit of the southern Widmerpool Gulf: a discussion

This review of the article by Kenomore et al. (2017) on the total organic carbon (TOC) evaluation of the Bowland Shale Formation in the Widmerpool Gulf sub-basin (southern Pennine Basin, UK) reveals a number of deficiencies, rooted mostly in an inadequate appreciation of the local Carboniferous stratigraphy. Kenomore et al. use the ΔLog R, the ‘Passey’ method after Passey et al. (1990), to evaluate the TOC content in two boreholes in the Widmerpool Gulf: Rempstone 1 and Old Dalby 1. We show here that Kenomore and co-authors used maturity data, published by Andrews (2013), from different formations to calibrate their TOC models of the Bowland Shale Formation (Late Mississippian–Early Pennsylvanian); the Morridge Formation in Rempstone 1 and the Widmerpool Formation in Old Dalby 1. We contest that this gives viable TOC estimates for the Bowland Shale Formation and that because of the location of the boreholes these TOC models are not representative over the whole of the Widmerpool Gulf. The pyrite content of the mudstones in the Widmerpool Gulf also surpasses the threshold where it becomes an influence on geophysical well logs. Aside from these stratigraphic and lithologic issues, some methodological weaknesses were not adequately resolved by Kenomore and co-authors. No lithological information is available for the Rock-Eval samples used for the maturity calibration, which because of the interbedded nature of the source formations has implications for the modelling exercise. We recommend that more geochemical data from a larger array of boreholes covering a wider area, proximal and distal, of the basin are collected before any inferences on TOC are made. This is necessary in the complex Bowland Shale system where lithological changes occur on a centimetre scale and correlations between the different sub basins are not well understood.

A rapid method for determining organic matter maturity using Raman spectroscopy: Application to Carboniferous organic-rich mudstones and coals

A simple and rapid automated Raman maturity method is calibrated using a suite of Carboniferous organic-rich mudstones and coals from the Inch of Ferryton-1 borehole in the Midland Valley of Scotland. Sediments in the borehole have been thermally matured by intrusion of a quartz dolerite sill, generating vitrinite reflectance (VR) values ranging from 0.5 to 6.0%VRo. Calibration curves are tested on eight other UK wells penetrating Carboniferous shales and coals in the Midland Valley and southern Pennine Basin. The G-band full-width at half-maximum (G-FWHM) is the best Raman parameter to estimate the thermal maturity of organic matter (OM) in the oil and gas window (0.5 to 3%VRo) and has a very strong correlation with VRo.

Clumped isotope evidence for episodic, rapid flow of fluids in a mineralized fault system in the Peak District, UK

We have used clumped isotope thermometry to study a fault-hosted hydrothermal calcite vein associated with the Mississippi Valley Type (MVT) mineralization on the Derbyshire Platform in the southern Pennines, UK. This is the first published dataset obtained using a new mass spectrometer, MIRA, optimized for clumped isotope analysis and an associated clumped isotope–temperature calibration. We analysed multiple generations of vein growth at high spatial resolution in two transects across the vein. The vein grew episodically at temperatures between 40 and 100°C. We interpret each episode of growth as being associated with an increasing flux of formation waters from deep sedimentary basins next to the mineralized platform and an accompanying increase in the precipitation temperatures. Heat is conserved in the fluid as it ascends along the fault surface and, thus, flow must have been fast and restricted to short-lived pulses. The flux could have been driven by high pore pressures associated with rapid sedimentation, hydrocarbon generation and diagenesis in the basinal facies of the Visean Bowland–Hodder group. Natural hydraulic fracturing of shale units and failure of capillary seals, possibly triggered by uplift, allowed the release of fluids into aquifers within the sediment pile. The transmission of high pore fluid pressures from the shales to the fault zone, aided by the compressibility of the gas phase in two-phase pore fluids, may have resulted in fault rupture, accompanied by enhanced fracture permeability and rapid fluid flow. Vein growth ceased as pore pressures dissipated. Such behaviour is closely related to a seismic valve type model for mineralization. Supplementary material: Details of the methods and equipment are available at https://dx.doi.org/10.6084/m9.figshare.3808329.v9

Sensitivity analysis of shallow planar landslides in residual soils on south Pennine hillslopes, Derbyshire, UK

Rainfall-induced shallow planar landslides on residual soil slopes are common mass movement processes on the southern Pennine slopes of Derbyshire, UK. They can be densely distributed across the region following intense rainfall events, frequently causing damage to infrastructure. This paper considers the results of slope stability sensitivity analyses using a simplistic Infinite Slope Stability Analysis (ISSA) model in shallow residual soils on the south Pennine hillslopes in Derbyshire. The results of the sensitivity analyses demonstrate how the factor of safety against shallow planar sliding changes as one geotechnical parameter is varied. An awareness of the variables involved in shallow planar translational landslides along with the knowledge of critical thresholds of certain geotechnical parameters establishes a basic context which assists the geotechnical engineer in the selection of key variables and making the correct engineering decisions in terms of remedial stabilisation solutions. The simple ISSA model used has limitations and recommendations are provided for improved field investigation methodology and modification of the simplistic ISSA model.

The prospectivity of a potential shale gas play: An example from the southern Pennine Basin (central England, UK)

During the Serpukhovian (late Mississippian) Stage, the Pennine Basin, now underlying much of northern England, consisted of a series of interlinked sub-basins that developed in response to the crustal extension north of the Hercynic orogenic zone. For the current study, mudstone samples of the Morridge Formation from two sub-basins located in the south-eastern part of the Pennine Basin were collected from the Carsington Dam Reconstruction C3 Borehole (Widmerpool Gulf sub-basin) and the Karenight 1 Borehole (Edale Gulf sub-basin). Detailed palynological analyses indicate that aside from the dominant (often 90% or more) heterogeneous amorphous organic matter (AOM), variable abundances of homogeneous AOM and phytoclasts are present. To complement the palynological dataset, a suite of geochemical and mineralogical techniques were applied to evaluate the prospectivity of these potentially important source rocks. Changes in the carbon isotope composition of the bulk organic fraction (δ13COM) suggest that the lower part (Biozone E2a) of Carsington DR C3 is markedly more influenced by terrigenous kerogen than the upper part of the core (Biozones E2a3–E2b1). The Karenight 1 core yielded more marine kerogen in the lower part (Marine Bands E1–E2b) than the upper part (Marine Band E2b). Present day Rock-Eval™ Total Organic Carbon (TOCpd) surpasses 2% in most samples from both cores, a proportion suggested by Jarvie (2012) that defines prospective shale gas reservoirs. However, when the pyrolysable component that reflects the generative kerogen fraction is considered, very few samples reach this threshold. The kerogen typing permits for the first time the calculation of an original hydrogen index (HIo) and original total organic carbon (TOCo) for Carboniferous mudstones of the Pennine Basin. The most prospective part of Carsington Dam Reconstruction C3 (marine bands E2b1–E2a3) has an average TOCo of 3.2% and an average HIo of 465 mg/g TOCo. The most prospective part of Karenight 1 (242.80–251.89 m) is characterized by an average TOCo of 9.3% and an average HIo of 504 mg/g TOCo. Lastly, X-ray diffraction (XRD) analysis confirms that the siliceous to argillaceous mudstones contain a highly variable carbonate content. The palynological, geochemical and mineralogical proxies combined indicate that marine sediments were continuously being deposited throughout the sampled intervals and were punctuated by episodic turbiditic events. The terrestrial material, originating from the Wales-Brabant High to the south of the Pennine Basin, was principally deposited in the Widmerpool Gulf, with much less terrigenous organic matter reaching the Edale Gulf. As a consequence, the prospective intervals are relatively thin, decimetre-to meter-scale, and further high resolution characterization of these intervals is required to understand variability in prospectivitiy over these limited intervals.

Prior to Peat: Assessing the Hiatus between Mesolithic Activity and Peat Inception on the Southern Pennine Moors

Palaeoecological investigation of soils exposed by eroding peat haggs on the moors above Tintwistle (Derbyshire) suggests that Mesolithic impact on upland soils between c. 360–500 m OD was not as dramatic, nor as long-lasting, as has sometimes been suggested. Despite evident erosion prior to peat inception, patterning has survived within Mesolithic scatters of artefacts. Neolithic activity is attested by both artefacts and charcoal-rich horizons suggesting intermittent burning of vegetation. Peat finally blanketed these uplands around the start of the second millennium cal. BC.These results demonstrate radically different scenarios at different altitudes within relatively small distances across the southern Pennines, shifting our appreciation of the chronology of changes in vegetation and erosion, as well as contributing to wider debate on the causes of moorland development, which can inform future land management.

Southern Pennine Brass Bands and the Creation of Northern Identity, c. 1840–1914: Musical Constructions of Space, Place And Region

In spite of being a national form of music-making, the brass band movement is accepted — almost without question in the popular imagination — as working class and northern. Hence, in 1974, Peter Hennessy described a band contest at the Albert Hall: ‘A roll call of the bands is like an evocation of industrial history. From Wingates Temperance and Black Dyke Mills to more modern conglomerates .... Grown men, old bandsmen say, have been known to cry at the beauty of it all …. Of all the manifestations of working-class culture, nothing is more certain than a brass band to bring on an attack of the George Orwells. Even the most hardened bourgeois cannot resist romanticising the proletariat a little when faced with one.(The Times, 11 Oct. 1974) This stereotype, which emerged in the nineteenth century, generated the following questions about northern identity: what elements in the brass band movement created this reportage of northern bandsmen and how did bands, which thrived in large numbers in the Southern Pennines, emerge as a musical and cultural metonym of the industrial landscape? This article explores notions of music-making and the creation of a musical space, place and region through the reporting of brass bands c. 1840–1914.

Using harvesting data to examine temporal and regional variation in red grouse abundance in the British uplands

Large areas of the British uplands consist of heather moorland, a habitat of global conservation importance that supports communities of threatened animal and plant species. Red grouse Lagopus lagopus scotica are dependent on heather and benefit from management of habitat, predators and parasites by gamekeepers employed to create a surplus of grouse for sport shooting. We compared numbers of red grouse shot across nine British regions over four discrete time periods (1890– 1920, 1920–1950, 1950–1980, 1980–2010) using annual records of shooting bags from 272 estates. We examined whether trends in numbers of grouse shot may be explained by changes in keeper density, heather moor extent or replacement of moorland by afforestation. Grouse bags were consistently higher in regions of northern England than in Scotland and Wales, and declined in all nine regions except southern Pennines from 1920 to 1950. Bags in northern England increased significantly from 1950, coinciding with increases in keeper density. In north‐east Scotland and Wales, numbers of grouse shot declined over the same period, coinciding with declines in keeper density and increased afforestation of moors. Regional variation in red grouse bag counts over time may be explained by changes in land use and management intensity affecting extent of suitable habitat and predator prevalence.

Palaeoenvironment, palaeoclimate and age of the Brassington Formation (Miocene) of Derbyshire, UK

The Brassington Formation is the most extensive Miocene sedimentary succession onshore in the UK. Because of its unique position at the margin of NW Europe, the pollen from this lithostratigraphical unit provides evidence on the development of vegetation affected by North Atlantic currents and hypothesized atmospheric circulation changes during the Middle to Late Miocene climate cooling. Palynostratigraphy suggests that the uppermost Kenslow Member of the Brassington Formation is not coeval. Previously, all occurrences of the Kenslow Member were assumed to be contemporary. The oldest pollen assemblage is from the more southern Bees Nest Pit, which represents a subtropical conifer-dominated forest of late Serravallian age ( c . 12 Ma). A younger assemblage was observed from the more northern Kenslow Top Pit; this indicates that a subtropical mixed forest was present during the early Tortonian (11.6–9 Ma). The shift from a conifer-dominated to a mixed forest was related to precipitation. Although the total precipitation did not change between the two assemblages, the younger assemblage had more uniform rainfall throughout the year. The diachronous nature of the Kenslow Member means that the depositional model of the Brassington Formation needs revising, and this will have implications for Neogene to recent uplift of the southern Pennines. Supplementary material: All valid formally defined palynomorph taxa below the generic level that are mentioned in this paper, with full author citations, are available at http://www.geolsoc.org.uk/SUP18889 .

New insight into the Quaternary evolution of the River Trent, UK

An exhaustive review of geological, palaeontological and archaeological data, coupled with selected new research and dating programmes using optically stimulated luminescence and amino acid racemization, has provided new insights into the origin and Quaternary evolution of the Trent river system. An important component of the new research was uplift/incision modelling based on the river-terrace archives from the greater Trent system, but also including dated speleothems in the southern Pennine valleys. The Trent came into existence following the Anglian (MIS 12) glaciation as a river draining the Dove, Derwent and Soar catchments via the Lincoln Gap and the newly eroded Fen Basin. Prior to that glaciation much of what is now the Trent catchment was drained by the Bytham system, which had its main axis significantly further south and flowed to the North Sea via East Anglia. Eastward Middle-Trent drainage from Derby to Nottingham only began with deglaciation of MIS 8 (Wragby glaciation) ice, which reached at least to the lower Soar and the Fen Basin. The widespread preservation of MIS 7 interglacial deposits in the Lower Trent and in Fen Basin valleys implies that no subsequent glaciation affected these areas. Late Devensian (MIS 2) ice reached the uppermost and lowermost Trent, possibly effecting diversion of the river into the Yorkshire Ouse, following overflow and subsequent emptying of Glacial Lake Humber.

Bacterial and fungal communities in a degraded ombrotrophic peatland undergoing natural and managed re-vegetation.

The UK hosts 15–19% of global upland ombrotrophic (rain fed) peatlands that are estimated to store 3.2 billion tonnes of carbon and represent a critical upland habitat with regard to biodiversity and ecosystem services provision. Net production is dependent on an imbalance between growth of peat-forming Sphagnum mosses and microbial decomposition by microorganisms that are limited by cold, acidic, and anaerobic conditions. In the Southern Pennines, land-use change, drainage, and over 200 years of anthropogenic N and heavy metal deposition have contributed to severe peatland degradation manifested as a loss of vegetation leaving bare peat susceptible to erosion and deep gullying. A restoration programme designed to regain peat hydrology, stability and functionality has involved re-vegetation through nurse grass, dwarf shrub and Sphagnum re-introduction. Our aim was to characterise bacterial and fungal communities, via high-throughput rRNA gene sequencing, in the surface acrotelm/mesotelm of degraded bare peat, long-term stable vegetated peat, and natural and managed restorations. Compared to long-term vegetated areas the bare peat microbiome had significantly higher levels of oligotrophic marker phyla (Acidobacteria, Verrucomicrobia, TM6) and lower Bacteroidetes and Actinobacteria, together with much higher ligninolytic Basidiomycota. Fewer distinct microbial sequences and significantly fewer cultivable microbes were detected in bare peat compared to other areas. Microbial community structure was linked to restoration activity and correlated with soil edaphic variables (e.g. moisture and heavy metals). Although rapid community changes were evident following restoration activity, restored bare peat did not approach a similar microbial community structure to non-eroded areas even after 25 years, which may be related to the stabilisation of historic deposited heavy metals pollution in long-term stable areas. These primary findings are discussed in relation to bare peat oligotrophy, re-vegetation recalcitrance, rhizosphere-microbe-soil interactions, C, N and P cycling, trajectory of restoration, and ecosystem service implications for peatland restoration.

Peatland restoration: controls on sediment production and reductions in carbon and pollutant export

AbstractPeatlands are an important store of soil carbon, and play a vital role in global carbon cycling, and when located in close proximity to urban and industrial areas, can also act as sinks of atmospherically deposited heavy metals. Large areas of the UK's blanket peat are significantly degraded and actively eroding which negatively impacts carbon and pollutant storage. The restoration of eroding UK peatlands is a major conservation concern, and over the last decade measures have been taken to try to control erosion and restore large areas of degraded peat. This study utilizes a sediment source fingerprinting approach to assess the effect of restoration practices on sediment production, and carbon and pollutant export in the Peak District National Park, southern Pennines (UK). Suspended sediment was collected using time integrated mass flux samplers (TIMS), deployed across three field areas which represent the surface conditions exhibited through an erosion–restoration cycle: (i) intact; (ii) actively eroding; and (iii) recently re‐vegetated. Anthropogenic pollutants stored near the peat's surface have allowed material mobilized by sheet erosion to be distinguished from sediment eroded from gully walls. Re‐vegetation of eroding gully systems is most effective at stabilizing interfluve surfaces, switching the locus of sediment production from contaminated surface peat to relatively ‘clean’ gully walls. The stabilization of eroding surfaces reduces particulate organic carbon (POC) and lead (Pb) fluxes by two orders of magnitude, to levels comparable with those of an intact peatland, thus maintaining this important carbon and pollutant store. The re‐vegetation of gully floors also plays a key role in decoupling eroding surfaces from the fluvial system, and further reducing the flux of material. These findings indicate that the restoration practices have been effective over a relatively short timescale, and will help target and refine future restoration initiatives. Copyright © 2014 John Wiley & Sons, Ltd.

PRACTITIONER'S PERSPECTIVE: Bridging the gap between applied ecological science and practical implementation in peatland restoration

PRACTITIONER'S PERSPECTIVE: Bridging the gap between applied ecological science and practical implementation in peatland restoration

The Carboniferous Southern Pennine Basin, UK

Many of the Carboniferous outcrops located in the Derbyshire region of the Peak District National Park, UK, have provided sites for both significant and pioneering research relating to the clastic sedimentology of marine palaeoenvironments, particularly so during the 1960s and 1970s when early models describing the sedimentary architecture of fluvio‐deltaic, submarine‐slope and deep‐marine submarine‐fan sedimentation were first developed. The area was subject to hydrocarbon exploration from the 1920s to 1950s, which although unsuccessful in economic terms left a legacy of sub‐surface data. Despite a long‐history of sedimentological research, the deposits exposed at several classic localities in the Pennine Basin continue to broaden and challenge our current understanding of sedimentary processes to this day.

Measurement of rates of surface lowering of limestone in the southern Pennines: an example in the Wye catchment, Derbyshire, UK

Measurement of the differential denudation between chert and limestone in a Carboniferous limestone sequence that was cut during excavations for a railway tunnel (in 1865) has provided a means of assessing limestone dissolution rates in a valley side setting in the southern Pennines over the last ∼150 years. Dissolution rates of 0.031 mm/annum have been determined. This rate falls within the range of previously determined limestone dissolution rates in the UK, which have been described in the context of different methods of measurement and the difference in denudations rates over time.

Predicting soil respiration from peatlands

This study considers the relative performance of six different models to predict soil respiration from upland peat. Predicting soil respiration is important for global carbon budgets and gap filling measured data from eddy covariance and closed chamber measurements. Further to models previously published new models are presented using two sub-soil zones and season. Models are tested using data from the Bleaklow plateau, southern Pennines, UK. Presented literature models include ANOVA using logged environmental data, the Arrhenius equation, modified versions of the Arrhenius equation to include soil respiration activation energy and water table depth. New models are proposed including the introduction of two soil zones in the peat profile, and season. The first new model proposes a zone of high CO2 productivity related to increased soil microbial CO2 production due to the supply of labile carbon from plant root exudates and root respiration. The second zone is a deeper zone where CO2 production is lower with less labile carbon. A final model allows the zone of high CO2 production to become dormant during winter months when plants will senesce and will vary depending upon vegetation type within a fixed location. The final model accounted for, on average, 31.9% of variance in net ecosystem respiration within 11 different restoration sites whilst, using the same data set, the best fitting literature equation only accounted for 18.7% of the total variance. Our results demonstrate that soil respiration models can be improved by explicitly accounting for seasonality and the vertically stratified nature of soil processes. These improved models provide an enhanced basis for calculating the peatland carbon budgets which are essential in understanding the role of peatlands in the global C cycle.