Characterising lake sediments by NIRS: integrating teaching and research in the Universities Central Teaching Laboratory

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A trend of ‘brownification’ identified in surface waters across the UK, North America and Northern Europe has been a growing concern, with the transfer of organic carbon from catchments to lake basins and water courses increasing. To explore this problem, in 2012-3 graduate teaching assistant Fiona Russell began PhD research investigating whether the sedimentary records preserved in lake basins provided new information on the longer term onset of this trend, the nature of any previous events in the last 11,500 years and the causes of browner surface waters. This research has used lakes in the UK Uplands Water Monitoring Network (formerly known as Acid Waters Monitoring Network), who for 30 years have collected data that shows some of these acid sensitive sites are affected by increases in the flux of dissolved organic carbon (DOC) and browner waters. The research involved accessing the sediments from these lakes and exploring for patterns that matched recent increases in monitored DOC and for other changes in the organic stratigraphy that might explain the patterns.
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Humic waters on the edge of Loch Grannoch

 At this time, the award winning state-of-the-art Central Teaching Laboratories (CTL) at the University of Liverpool expanded the Infrared Spectrometry capabilities adding a Near-infrared Diffuse Reflectance machine. The Bruker MPA Diffuse Reflectance Fourier Transform Near Infrared Spectrometer (FT-NIRS) was added to the teaching facility to enable the rapid and non-destructive characterisation of powders including soils and sediments. NIRS has proven to be a valuable tool for quantifying the components present in lake sediments, such as type and quantity of organic and mineral matter. Often the approach uses direct comparison of the NIR spectra to parallel independently measured parameters, for example organic content (loss-on-ignition or total organic carbon). This approach requires the development of an extensive training set of parallel measurements, and one has been developed in the CTL to enable undergraduates and postgraduates to estimate loss-on-ignition by NIRS. The NIRS measurement takes 60 seconds and is non-destructive, whereas equivalent combustion methods take several hours, are destructive and more difficult to accommodate in the time frame of practical classes.
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MPA FT-NIRS in the Central Teaching Laboratory

In developing utilities to support teaching in the School of Environmental Sciences, Fiona Russell began exploring alternative approaches to the handling of NIR spectra to obtain a broader range of environmental information from sediments and soils. The approach developed rather than using a large training set, for example our loss-on-ignition dataset comprises > 200 samples with parallel NIRS and l-o-i measurements, instead uses a library of end member NIR spectra measured for known composition materials e.g. biogenic silica (diatoms), humic/fulvic acids (key components of DOC), rock and mineral types. This alternative approach, recently published in the Journal of Paleolimnology (click here), applies a multiple regression of a selection of known material NIR spectra to a sample set of NIR spectra measured for unknown composition materials, in this research lake sediment samples. The research shows that with appropriate selection of 3-5 end member spectra, the method can reconstruct successfully the proportions that these end members form in the series of unknown lake sediments. This different approach means that environmental reconstructions can be undertaken using 3-5 end member spectra rather than a library of >100-200 parallel measurements and it can reconstruct the proportions of multiple end member materials or sediment components simultaneously.

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To demonstrate the approach, we sampled a 14,500 year duration sediment core from Loch Grannoch in the Galloway Hills (SW Scotland). Loch Grannoch is a small upland oligotrophic lake that has granite bedrock, relatively large catchment area and is one of the lakes in the UK Uplands Water Monitoring Network. Applying our approach reveals a down-core pattern of varying dominance by biogenic silica, organic and mineral content from the late glacial to present. Testing a wider range of end members shows there is sensitivity to the choice of end members, with a local bedrock or sediment end member characteristic of the lake catchment important. The wider generality of the approach, and the utility of our growing library of mineral, organic and biogenic silica end-member materials, is demonstrated by successful ‘blind’ application to additional lake sediment cores from Wales, Norway and Sweden each with differing climate and bedrock.
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Fitting mineral, organic and biogenic silica end members to multiple lakes.

The technique development embedded in this research showcases the importance of integrating teaching and research at the University of Liverpool. The paper is available as Open Access from the Journal of Paleolimnology should you wish to read more about it. The team have made available the library of end member NIR spectra and the multiple regression method code developed using the open source R platform with the the online version of the paper supplementary materials and in the University of Liverpool DataCat archive. The methodology is now being used routinely by colleagues, undergraduate and postgraduate students to characterise materials in their learning and independent research. For further information please contact the authors: Fiona Russell, John Boyle and Richard Chiverrell.

 

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Learning Machine Learning Open Workgroup (LMLow) Hackathon

Following on from the successes of the first three sessions of LMLOW, we are proud to announce our first ever hackathon event! The event will be entirely hands-on and provide an opportunity for individuals to gain practical experience in utilising the two methodologies that we have covered so far: (1) Regression Trees and Gradient Boosting, and (2) Word2vec and text mining

The hackathon will focus on analysing a single data set: AirBnb reviews in London provided by Inside Airbnb. The data include geographically referenced reviews for airbnb lodgings and includes a mixture of numerical and text data. The data can be found here (search for London). 

Please come prepared having examined the data source and the potential questions that could be explored using the data. During the event, individuals will be split into small teams who will identify and explore research questions utilising the two methodologies, under the guidance of our team of experts. Participants will be required to bring their own laptop with relevant statistical software pre-installed (e.g. R/RStudio, Python, QGIS etc). There will be a prize for the team who completes the best project.
You can sign up for the event at this link.

Understanding Polish Migration to the UK

New blog post by Dr Kathy Burrell

In my academic research I have focused on Polish migration to the UK. I have done this largely through interviewing Polish migrants directly – in-depth interviews which allow time to talk about key experiences and feelings related to migrating from Poland to the UK. I have interviewed people who were refugees from the Second World…

Reblogged – follow this link to read the full post Understanding Polish Migration to the UK — Kathy Burrell

Carceral Geography comes to Liverpool

Post by Dr Jennifer Turner

Human Geography at Liverpool has a strong reputation for the study of socio-spatial exclusion, inequality, geographies of the life-course and developing understandings of moving, mobile populations. As a new Lecturer in Human Geography, I’ve been excited to join this vibrant department, bringing to it, a further way of thinking about those themes – through the study of so-called ‘carceral’ life – or, in layman’s terms, thinking about the geographies of places of imprisonment, detainment or confinement and the people who are involved with these spaces.

My research focuses upon spaces and practices of incarceration, past and present. Most recently, I have interrogated prison architecture, design, technology and their potential to impact upon rehabilitation. Other interests include penal tourism, articulations of the prison boundary and conceptualisations of carceral space. My work has been published widely in the fields of carceral geography and criminology.  Please see my website for further details.

I’ll be bringing this specialism to Liverpool through a variety of teaching at undergraduate level and postgraduate level, including the modules ENVS385 Issues in Geography and ENVS434 Space, Power and Culture.

Here will be will thinking about a range of themes; some covered in a new book entitled Carceral Mobilities: Interrogating Movement in Incarceration just published with another Liverpool geographer, Dr Kimberley Peters.

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The book has been an exciting, cross disciplinary project. At first glance, the words ‘carceral’ and ‘mobilities’ seem to sit uneasily together. Yet, through its introduction and 17 chapters, the book challenges the assumption that carceral life is characterised by a lack of movement; and that mobilities scholars may find no obvious interest in supposed spaces of confinement and stasis – the prison, camp or asylum centre. Identifying and unpicking the manifold mobilities that shape (and are shaped by) carceral regimes, the book brings together contributions that speak to contemporary debates across carceral studies and mobilities research, offering fresh insights to both areas of concern. It features four sections that move the reader through the varying typologies of motion underscoring carceral life: tension; circulation; distribution; and transition. Each mobilities-led section seeks to explore the politics encapsulated in specific regimes of carceral movement.

It is now argued that mobilities research is ‘centre stage’ in the social sciences with wide-ranging work that considers the politics underscoring the movements of people and objects. From studies that examine technologies of motion, to the infrastructures that enable/disable mobility; and from investigations of the subjects made mobile or immobile by regimes of regulation, to the materialities that shape and are shaped by mobilities, what this turn has come to achieve is a critical consideration a world that is ever ‘on the move’. This book, however, offers a fresh perspective on these questions, exploring mobilities through a carceral lens.

Featuring contributions from leading academics working in the field of carceral studies and mobilities research (as well as a strong selection of chapters from emerging scholars, freelance writers and social workers), the book brings together timely discussions in one collection, which will appeal to wide, cross-disciplinary audiences, contributing firmly to current conceptual debates shaping the social sciences. Indeed, drawing on a range of international examples (from the UK, Europe, Australia, South-East Asia, North and South America), the book offers an authoritative, global collection on the theme of carceral mobilities, from a variety of disciplinary perspectives including Criminology, Sociology, History, Cultural Theory, Human Geography and Urban Planning. A foreword and afterword will be provided by established figures in carceral geography (Dr Dominique Moran) and mobilities studies (Professor Peter Merriman), also illuminates how understandings of ‘carcerality’ and ‘mobility’ can each inform the other.  The book therefore offers a first port of call for those examining spaces of detention, asylum, imprisonment and containment, who are increasingly interested in questions of movement in relation to the management, control, and confinement of populations.

You’ll be able to access this in the library soon!

Keeping things moving A to B: why what happens at sea matters

 

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The Trans Future unloading in Auckland, NZ. Ships help to carry 96% of goods around our world (Photo: K Peters)

Post by Kimberley Peters

Breaking chains: the threat of piracy

Just a few years ago the threat of piracy – the seizure of huge cargo ships and the holding hostage of their crews –  loomed large off of the coast of Somalia. This illicit maritime activity, which is many centuries old and can be traced back to the earliest seafaring (see Hasty 2014), was a cause for global concern. Ships are the technologies that link spaces together for the majority of trade (96% to be exact). Moreover, much of that trade travels through piracy ‘hotspots’ – voyaging through the Suez Canal linking Europe with the Middle East and South-East Asia.

As was depicted in the Hollywood film Captain Phillips (based on the events experienced by the real Captain Phillips) piracy has costs. There are, for shipping companies, large economic costs of training crews, installing water cannons and locking systems onto vessels, and, of course, rising insurance premiums. At the height of the piracy crisis (which coincided with a fall in oil prices) it was cheaper for vessels to travel around the African continent, following 18th and 19th century colonial trade routes, than to journey via Suez and the Somali coast. Higher costs for shipping translate, ultimately, into higher costs for us as consumers. But there are also other costs – the costs to lives, of those victim to piracy, but also those in war-torn countries who commit such offshore acts.

The spate of piratical acts over the last decade has alerted the world to the often invisible world that exists offshore (Urry 2014). It has also alerted us to the fact that the chains that keep things moving A to B, are not unbreakable. When we go shopping – for food, clothes, a new mobile phone – almost all of these things will have travelled on a ship across the oceans, connecting us to the world beyond dry land and to the lives of those offshore who are making (and breaking) those commodity chains (see Peters 2010).

Today, we hear less of piracy in the news. This is partly due to better oceanic governance to prevent it, and efforts onshore to assist the rebuilding of communities who often have little option but to turn to crime at sea (see the excellent work of Gilmer on piracy in the recent issue of Geoforum, 2016). But just because piracy is not as visible as it has been, doesn’t mean that it is all plain sailing for those who facilitate the supply chains that keep our shop shelves stacked.

Stuck in limbo: when shipping companies go bust

In the past few months we’ve seen a new crisis emerge as global shipping firm Hanjin went bust. As geographers Stephen Graham and Nigel Thrift have argued (2007), we often fail to recognise the infrastructural systems that keep our world functioning: the pipes, cables, roads, cars, planes and even ships – that are part of networks which keep things moving A to B. It is only when things fail we notice these invisible systems (piracy for example, made the closed world of shipping suddenly very visible). The Hanjin crisis did the same.

When the company was declared insolvent, ships and their crews were stuck out at sea with nowhere to go (see this BBC report). Ports refused them entry knowing the bankrupt company would not be able to pay the port fees. Captains and workers were stranded on board. The thousands of container boxes carried by the ships were undelivered – trapped in an oceanic limbo. Supply chains were severed. Cars failed to arrive in showrooms. Electrical goods failed to reach their destination. Personal items shipped overseas were left bobbing about offshore. Again, this instance alerts us to the fundamental but fragile role of shipping in everyday life.

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Viewed from the New Brighton beach, the Liverpool2 container port. This recent development will enable the city to welcome some of the world’s largest vessels (Photo: K Peters)

Keeping things moving: new developments

In recent months we have been confronted with the global world of shipping in new ways here in Liverpool. The opening of the new Liverpool2 docks in November 2016 will enable the world’s largest ships – of 400 meters and above – to enter the port. Liverpool, it is anticipated, will become a new hub of global trade in the North of England – a key site for enabling those vital connections that move things from A to B (see this BBC report).

The difference this will make for Liverpool, the north-west region, and to the world of commerce and trade is, as yet, unclear. It is argued it will bring more jobs and greater prosperity to the area. It may also create new global links between Liverpool and the rest of the world. As such, what happens at sea, on ships, and in ports matters to us here on land (as myself and colleagues have argued elsewhere, see Anderson and Peters 2014). Developments like Liverpool2 are part of the network of infrastructures that keep things moving and enable us to access the goods and resources essential to our daily lives (see also this recent article on the Geographical Magazine website).

So next time you go shopping, spare a thought for the oceanic connections interwoven with the things you buy, and the geographic processes, and infrastructural maintenance that has enabled them to reach our shores. And if this has sparked your interest, we explore some of these themes in the new ENVS339 Maritime Geographies module in the Department of Geography and Planning in Spring 2017, taught by myself, Prof. Andy Plater and Dr. Andy Davies.

Introducing James Lea: New Lecturer in Glacial Geomorphology

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Post by Dr. James Lea

I’m James Lea, and I’ve just started in the department as a new lecturer in glacial geomorphology.

My research looks at how glacial and geomorphic processes can aid our understanding of the past, present, and potential future behaviour of glaciers and ice sheets, though I also have more general interests in Quaternary environments, remote sensing, and numerical modelling techniques.

One of the main areas I research is the behaviour of tidewater glaciers (those that flow into the sea), since these are amongst the largest and fastest on the planet, and potentially the most likely drivers of future rapid sea level rise. I started to study these types of glaciers during my PhD at the University of Aberdeen, where I reconstructed the last 250 years of behaviour at the largest and most dynamic tidewater glacier in SW Greenland (the catchily named Kangiata Nunaata Sermia).

As part of this, I used a variety of information including satellite imagery, explorer’s photographs, geomorphology, and forgotten diaries of early Greenland colonists to reconstruct glacier positions. The result was the longest observation based record of tidewater glacier dynamics anywhere in Greenland, which I then was able to use to test whether a numerical model could adequately simulate the decadal to centennial behaviour of these glaciers.

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Following my PhD, I moved from Aberdeen to Stockholm University, Sweden to take a postdoc position looking at performing simulations of the former Svalbard-Barents Sea Ice Sheet (north of Scandinavia) that existed during the last glacial. During this time I was also researching how iceberg calving processes are incorporated into ice sheet models, with the aim of improving how this significant but poorly understood mechanism of ice loss is represented.

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In addition to these mostly model and remote sensing based studies, I also very much enjoy taking part in field-based research. Some of examples of this have included: nearly getting heat stroke in an Essex Quarry (Quantification of turbate structures through a subglacial till: dimensions and characteristics, Lea & Palmer, 2014); standing in a lake for 6 hours in the middle of the Swedish winter coring for sediments (Timing of the first drainage of the Baltic Ice Lake synchronous with the onset of Greenland Stadial 1, Muschitiello, Lea, et al., 2015); and hiking round Greenland for 4 weeks at a time carrying everything on my back (Terminus driven retreat of a major Greenlandic tidewater glacier during the early 19th century, Lea et al., 2014a; Fluctuations of a major Greenlandic tidewater glacier driven by changes in atmospheric forcing, Lea et al., 2014b).

If you have any questions just drop me an email (j.lea@liverpool.ac.uk), or call by my office (Rm404 in the Roxby Building) to say hello!

‘Knowing me, Knowing you’

 By Mark Green

I have just joined the department to take up a Lectureship in Health Geography here at the University of Liverpool.

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Mark himself!

My research interests lie in two interconnected areas. Firstly, I am interested in how body weight and physical activity vary within the UK population, as well as their association to various health outcomes. Secondly, I am interested in examining how neighbourhoods influence health outcomes and behaviours. I also have a broad interest in social inequalities in health and in understanding the processes through which they persist.

I joined the department having previously been based at ScHARR (School of Health and Related Research, University of Sheffield), where I was a Research Associate in Public Health (2013-2015). I was attached to two large research projects during this post:

  • The Yorkshire Health Study: A survey of residents of Yorkshire collected every three years which began in 2010-2012. The aim of the survey is to better understand the health needs of the population of Yorkshire, as well as investigate the associations between a variety of personal, social and behavioural factors to long term health conditions. The study was funded by the NIHR CLAHRC for Yorkshire and the Humber.
  • An analysis of the associations between the density of different types of shops which sell alcohol and alcohol-related admissions to hospitals at a small geographical scale (2002/03 to 2013/14). The study was funded by Alcohol Research UK.
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Mark is involved in the Global Burden of Disease study, which estimates worldwide trends in health. This figure is of the prevalence of overweight and obesity (source: Ng et al., 2014, Lancet, 384: 766–81).

Despite having a Public Health background, I am a Geographer by trade. I completed my PhD in Geography at the University of Sheffield (2010-2013), entitled ‘Death in England and Wales: Using a classificatory approach for researching mortality’ (supervised by Dr Daniel Vickers and Prof. Danny Dorling). My PhD explored the clustering of mortality patterns at a small scale for England and Wales through the creation of an area classification. I also have a MSc and BA(Hons) in geographical-related disciplines both from the University of Sheffield.

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Mark’s PhD created an area classification of mortality patterns for England and Wales. Of course, as a geographer he loves maps! (Source: Green et al., 2014, Health & Place, 30, 196-204).

A list of my publications can be found here. If you have any questions or fancy a chat, feel free to pop by my office (Room 602c in the Roxby Building), or email me.