Faculty of Arts and Sciences Graduate Teaching Assistantships/PhD Studentships

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1 Faculty of Arts and Sciences Graduate Teaching Assistantships/PhD Studentships About Us The Faculty of Arts and Sciences is home to a large and diverse group of disciplines with a track record of excellence in research, much of which crosses traditional disciplinary boundaries. We are particularly keen to continue to build our research capacity, and welcome applications for up to 12 PhD studentships spread across all subject areas in the Faculty. All the studentships will be combined with Graduate Teaching Assistantships (GTAs). Geography Research interests in the Department of Geography span a wide range of geographical and geological subjects, including palaeoenvironmental reconstruction, environmental and climatic change, peatland carbon cycling, fluvial geomorphology and flooding, modelling coastal processes, clastic sedimentology and fossil records, volcanology and geochemistry, environmental remote sensing, and cultural and heritage geographies. Research in the Department is aided by high quality laboratories and specialist ICT facilities. Staff have developed an extensive network of research links with environmental organizations and other universities in the UK and overseas. We welcome applications across our full range of research interests and general enquiries may be addressed to Professor Paul Aplin, paul.aplin@edgehill.ac.uk. See our list of example project outlines below: Geo 1. Palaeofire Fire is an important disturbance mechanism in the Earth system, affecting ecosystems and the global carbon cycle. It has been present in the geological record since the appearance of terrestrial plants and some eight billion tonnes of vegetation are burned each year by natural wildfires. Our knowledge of past fire regimes is key to understanding the relationship between burning, climatic change, vegetation patterns and anthropogenic activities, especially as this is becoming increasingly important for conservation and management practice. Investigations into the drivers of fire regimes have been conducted both on a European scale and globally using palaeoclimatic reconstructions. However, regional understanding of paleofire regimes is integral for management practice development. The project will aim to identify the changing dominant drivers and controls of fire throughout the early, mid and late Holocene, utilising both primary and secondary proxy data, i.e. charcoal, pollen, etc. from a range of locations. The combination of charcoal and vegetation data, using related pollen records will provide information on vegetative response to fire and human manipulation of the environment through the use of fire.

2 Geo 2. Palaeoenvironmental change The Department of Geography has a strong Environmental Change research background focussing on palaeoenvironmental and palaeoclimate reconstructions, which incorporates the application of palaeoecology, geochemistry and geochronology and the study of peat bogs, lakes, small forest hollows, glaciers, rivers, deserts and high mountain terrains. A range of expertise and techniques are represented, these include, but not exclusively: Diatom, Pollen, Tephra and Charcoal analysis. Potential PhD project areas are: Stand-scale palynology and woodland history Fire history and regime change Palaeoecology and contemporary management Tephrochronology Palaeohazards Palaeo climate regimes We would welcome applications/research proposals on other themes of environmental change that are consistent with the expertise and techniques available in the Department.

3 Geo 3. A multi-proxy approach to stand-scale palynology investigations Stand-scale palynology is the study of pollen preserved close to its source vegetation, generally in sediments accumulated within the woodland and under the forest canopy. Stand-scale investigations provide useful data for management and conservation of a site as detailed long-term ecological information is provided. Small Forest Hollows (SFH) in the forest floor accumulate sediment and preservation of microfossils is aided by water-logged conditions. There has been limited use of these environments in the UK; England (Bradshaw 1981; Birks 1982; Day, 1993; Bradshaw, 2014); four sites in Wales (Edwards, 1986). Stand-scale investigations have used pollen as their primary proxy and have not utilised other techniques, most notably diatoms. Diatoms are unicellular algae that live in water, of which SFH would be a suitable habitat and depositional environment. Their distribution is controlled environmental variables e.g. ph, salinity, temperature, and nutrient supply. Diatoms rapidly respond to catchment wide environmental change, such as changes in vegetation. Vegetation type and density can influence the intensity of erosion, and the input of terrestrial material can affect the aquatic system. Further, diatoms have proven to be useful to detect anthropogenic disturbance. The project will explore the similarity in these fossil records of woodland disturbance and management.

4 Geo 4. Storm impact at a rapidly eroding sandy coastline Coastal dunes are one of the most efficient natural barriers against coastal flooding. The erosion of frontal dunes as a result of wave action is relatively well understood and modelled. However, the geomorphological response of coastal dunes to both wave and wind processes is relatively poorly integrated, mainly due to a lack of comprehensive data on dune response to winds, and aeolian sediment transport during supply-limiting conditions. Additionally, different dune configurations/morphologies including varying vegetation assemblages can lead to very different dune responses to similar storm action along the same coastline. This project will explore the response to storminess of one of the fastest eroding sandy coastlines in Europe: the Sefton dunes. The dunes erode at a rate of 4m year -1 and comprise a range of dune shapes, heights, and vegetation communities. Field data (e.g., TLS surveys to monitor dune and beach slopes and vegetation, sediment types, nearshore bathymetry, etc.) and modelling (e.g., SWAN, XBeach, and CFD) will be combined to characterize forcing parameters and resulting morphological changes as a result of strong waves and winds in this area.

5 Geo 5. Investigating anthropogenic impacts on coastal dune evolution using airborne lidar and hyperspectral image data Coastal dune fields form a natural defence against flooding and coastal erosion, a defensive role that becomes more vital with predictions of significant sea-level rise throughout the 21 st century. Sand dunes, though, are notoriously dynamic phenomena constantly shifting position, size and shape in response to environmental, and anthropogenic, pressures and we lack basic knowledge about how they evolve over time. This project aims to map, model and monitor Sefton Coast SAC, the largest dune field in England, investigating how dune evolution relates to natural and human processes. The research will be conducted as part of a 2018 NERC Airborne Research Facility data grant, providing airborne lidar and hyperspectral image data. Lidar data will be acquired to generate detailed 3D representation of the dune field, and this will be compared against a rich set of recent lidar acquisitions by the Environment Agency, enabling temporal analysis of dune morphology since Hyperspectral imagery will be acquired to classify vegetation and other land cover over the dune field, indicating how factors such as distance from coast, position on/in dune and proximity to human development influence vegetation cover. Lidar and hyperspectral data outputs will then be combined to drive predictive roughness modelling of dune evolution. Finally, dune morphology will be compared against environmental and anthropogenic impacts to start to unpick the causes of dune evolution over time.

6 Geo 6. Spatio-temporal resilience of high-value grazing lawns against broader land cover change in southern Africa savannahs Savannah ecosystems encompass one fifth of the terrestrial landscape worldwide. In many southern African savannahs, isolated grassy patches occur within tree-dominated landscapes, and these grassy patches are of great importance for herbivores such as impala (Aepyceros melampus), wildebeest (Connochaetes taurinus), zebra (Equusburchellii), and white rhino (Ceratotherium simum). Grazing lawns are highlyutilized grassland patches with nutrient-dense, palatable plants which attract herbivores in high numbers, and represent key food resource areas. Researchers are beginning to understand the significance of grazing lawns as a functioning resource within savannah ecosystems, but less is known about the dynamic nature of lawns over space and time. More importantly, we lack a robust, broad-scale mechanism for identifying and characterizing grazing lawns which would enable investigation of the structural differences between grazing lawns and surrounding areas, and the resilience of grazing lawns to broader landscape change. A better characterisation of grazing lawns is essential to elucidate the mechanisms driving lawn origins and maintenance to better predict how they may respond to future impacts such as climate change, exotic species invasions, and the broader-level landscape change and scrubbing up currently observed across regions of Africa. Here, we propose to use high resolution satellite imagery to map and characterise grazing lawns, quantify the spatial structure of lawns and surrounding areas, and monitor the changing distribution of these lawns with potential implications for large herbivore species.

7 Geo 7. Investigating textural and mineralogical changes prior to a volcanic eruption in Villarica, Chile Villarrica volcano (39.42 S, W) is one of the most active volcanoes in Chile, with more than 55 eruptions in the last 500 years. Villarrica is a basaltic andesite stratovolcano, with open-system degassing and a lava lake. The volcanic activity switches with little or no warning from mild or moderate activity within the lava lake into major eruptions, of which the last one occurred in Specifically, the 2015 eruption exemplified the sudden changes in eruptive style; on 3 March activity increased over only a few hours, culminating in a violent strombolian eruptive phase lasting ~55 minutes. The eruption ejected tephra, ballistics, an amount of agglutinated spatter on the area around the vent, and produced a few small lahars around the slopes of the cone. By 6 March the seismic activity dropped to below the usual background level, returning to the typical values by 10 March. The project will assess and quantify what triggers a major volcanic event at Villarrica, studying the geochemistry and textures of the volcanic products from before and during eruption.

8 Geo 8. Measuring the missing carbon Peatlands are the world s largest soil carbon store containing as much carbon as the atmosphere in 2-3% of the land area. There is intense pressure upon these ecosystems due to climate change and human induced land use change. Scientific study is essential in order to understand and preserve these carbon stores. Current technology allows us to directly measure how much carbon is stored in a peatland, and whether peatlands are sinks or sources of carbon. What is currently unknown is how these ecosystems respond to changes in the climate. In particular, can we quantify historic carbon losses, and what the future will hold for these carbon stores? This studentship will develop and test a novel approach to constrain long-term carbon losses for a peatland where contemporary carbon emissions are being measured. The site chosen for the study has had 0.5 million in scientific infrastructure and investment and measurements have been conducted for the past 6 years. Furthermore, climate manipulation trials are being conducted at the site that will allow reconstructed and contemporary budgets to be viewed in the light of future climate change on peatlands. This project will run in collaboration with research partners at Durham University and the University of York.

9 Geo 9. Extending flood records using evidence from floodplain environments River floods are a hazard to populations and infrastructure located within the floodplain. Floodplains preserve evidence of past floods in the form of sediments deposited by overbank flows. Grain sizes of the deposited sediment are determined by flood magnitude, along with factors including sediment supply and floodplain topography. Sedimentary evidence for floods that occurred prior to the start of river flow gauge records can be used to extend flood records and constrain estimates of the frequencies and magnitudes of relatively infrequent, high-magnitude flood events. This project aims to study magnitudes and frequencies of flood events on centennial to millennial timescales in selected river catchments using analysis of floodplain sediments. It builds on previous work in river systems in Wales on methods for extracting flood records from floodplain environments and will use a range of techniques to examine floodplain geomorphology and sediment characteristics.