Fluvial landscapes in the Roman world

Dr Tyler V. Franconi provides an overview of a new book exploring the role of rivers in Roman times.

Fluvial Landscapes in the Roman World is a newly published edited volume that emerged from the 2014 conference Shifting fuvial landscapes in the Roman world: new directions in the study of ancient rivers held at All Souls College in association with the Oxford Roman Economy Project.

Much of Roman history has viewed the landscape as a backdrop for history — a passive recipient of Roman imperialism: we wanted to move beyond this narrative. The conference and publication brought together experts in the history, archaeology, and geomorphology of the Roman world in order to understand better how Rome influenced the environment and how the environment, in turn, influenced Rome.

Rivers offered a particularly dynamic window into this topic, as they were a central focus of Roman settlement and economic activity across Europe, western Asia, and northern Africa, and therefore provided ample discussion of similarities and differences in Rome’s interaction with riverine landscapes in markedly different landscapes.

The volume begins with an introduction setting out how the study of rivers can contribute to new narratives of Roman history. This chapter synthesizes a large body of earlier geo-archaeological investigations from many parts of the Roman Empire, demonstrating widespread and repeated encounters between rivers and settlements.

Three main themes come out of this synthesis: mainly that studying rivers can help clarify the relationship between the Roman Empire and its changing climate; rivers can also help document Roman impacts on the environment through actions like agricultural production, deforestation, and mining; and that rivers often have significant roles to play in the shaping of historical narratives.

These historical narratives are explored further through subsequent chapters. Specific case studies from France, Italy, Germany, Syria, and Egypt accompany regional overviews of North Africa and the Mediterranean littoral, examining how hydrological events like floods, sedimentation, channel movement, droughts, and delta progradation influenced settlement location, economic networks, transportation systems, agricultural schemes, and irrigation networks.

Amongst these investigations of the physical interactions between river and society, the contributing authors also examine firsthand accounts from Greek, Roman, and Medieval sources that discuss ancient impressions and explanations for hydrological activity. These ancient sources make it clear that the hydrological processes were well understood by contemporaries, even if the Empire was not always able or willing to counteract environmental forces.

These written accounts provide invaluable evidence, which when considered alongside archaeological and geomorphological studies, document the social context of riverine activity of the time. Together, these papers make it clear that it is only through a contextualized consideration of all available evidence that we can begin to grasp the significance of the ancient environment in shaping Roman historical narrative.

We hope that these papers, synthesizing multidisciplinary research across the Roman Empire, will be of interest to many researchers, and will advance the study of Rome and its environment.

The book is published as a supplement of the Journal of Roman Archaeology and is available for purchase through the journal’s website, and the front matter is available for preview.

For further details contact Dr Tyler V. Franconi.

Possibilities and pitfalls of community-based financing of water supplies in rural Kenya

Dr Tim Foster sheds lights on three decades of water payment records from Kwale County.

The national water policies of most African countries stipulate that rural communities are responsible for covering their water supply operation and maintenance costs. However, emerging data from large-scale waterpoint inventories reveal a considerable gap between the policies on paper and reality on the ground.

Of the 90,000 handpumps installed on wells and boreholes in Sierra Leone, Liberia, Uganda and Tanzania, fewer than half are accompanied by any form of revenue collection system. The operational implications of this situation are plain to see, with hundreds of thousands of waterpoints across rural Africa in a state of disrepair.

To better understand the drivers and dynamics of rural waterpoint financial flows, our team of researchers, from the Smith School of Enterprise and the Environment, studied Kenya’s Kwale County, a region that bore witness to one of the first large-scale hand pump deployments in Africa.

In 2013, we assembled an inventory of handpumps located in the coastal regions of Kwale as part of a wide-ranging study into rural water service sustainability. As is the case in many other regions of rural Africa, a high proportion of the waterpoints identified were non-functional (42%) and breakdowns were lengthy (average of 1 month).

Of the 518 communal handpumps located, around half were coupled with a system for collecting regular fees. There was an even split between those levying a flat monthly fee and those collecting a volumetric ‘pay-as-you-fetch’ tariff based on the quantity of water consumed.

As we delved deeper into the financial aspects of handpump water supplies in Kwale, it became apparent that a sizable number of communities maintained written records of user fee payments. Upon closer inspection, these records proved to be a treasure trove of information, with some documents stretching back to the mid-1980s.

All told, the records comprised more than 43,000 monthly fees payments, with revenue data spanning more than 270 water service years, and expenditure data covering 140 water service years.

This unique multi-decadal data set yielded a multitude of novel insights into the predictors and patterns of rural water supply financial flows, as well as the broader implications for the operational performance of waterpoints and water source choices of households. The investigation culminated in two papers – one published in the Journal of Rural Studies, and another in Water Resources Research.

Overall, we found that in the long-run, around 1 in 4 water users fail to pay their monthly fee each month, resulting in a shortfall of revenue. Late payment is also common: by the beginning of 2014, the payments received for water use in 2013 were about half what they should have been.

Multivariable regression analysis revealed that payment levels were associated with a number of social and environmental factors. Financial contribution rates tended to be higher when the water point was located close to households; when users considered the water palatable; when the water was put to productive use; and when there was little or no rainfall during the month.

The revenue collection approach adopted by communities also appeared to have a major bearing on financial and operational outcomes. Those collecting “pay-as-you-fetch” fees on a per bucket basis generated substantially more revenue than other approaches (e.g. monthly payments, ad hoc payments upon breakdown). This financial advantage also translated into significantly faster repair times when water points broke down.

The flipside was that “pay-as-you-fetch” payments also seemed to push a higher proportion of households towards use of unimproved drinking water sources. There were two likely reasons for these outcomes. First, free-riding is almost impossible under a “pay-as-you-fetch” model due to the requirement for pre-payments. Second, the average unit price for water under a “pay-as-fetch” arrangement was equivalent to US $1.30 per cubic metre – a rate that is more expensive than piped water in some urban areas of high-income countries.

These findings shine a spotlight on several conundrums facing policy makers and practitioners, particularly given the elevated ambition of the Sustainable Development Goal to achieve safe drinking water for all.

First, the data revealed great variation in the willingness and ability to pay for water, both within and between communities. Second, most of the factors linked with lower payment rates were characteristics which appear to be difficult to address (e.g groundwater quality, settlement patterns, rainfall). Third, the revenue collection system that leads to the most sustainable services also seems to have perverse impacts on the water source decisions of some households.

All of these observations point to a more fundamental question: can universal access to safe drinking water be achieved in rural Africa based on the current policy paradigm of community-based financing of operation and maintenance? An answer in the affirmative assumes rural water communities universally possess the willingness and wherewithal to cover the costs of operation and maintenance. The evidence from three decades of experience in Kwale shows that this assumption does not always hold.

About the author
Tim Foster is a Chancellor’s Postdoctoral Research Fellow at the University of Technology Sydney’s Institute for Sustainable Futures. His current research investigates the role of entrepreneurs and enterprise in rural water service delivery in Asia and Africa. He received his doctorate from the University of Oxford for research conducted at the Smith School of Enterprise and the Environment under the supervision of Dr Rob Hope, Director of the Smith School’s Water Programme.

On the trail of freshwater invaders

The Thames is one of the world’s most highly invaded freshwater ecosystems. Researchers from Oxford University’s Department of Continuing Education explore the increasing colonization of non-native amphipod species in the river basin.

Dr Jocelyne Hughes, Director of the Department for Continuing Education’s Postgraduate Certificate in Ecological Survey Techniques, is investigating an aggressive freshwater predator which has invaded English waterways with the potential to alter the aquatic ecology and to call existing management practices into question.

The culprit is called ‘demon shrimp’ – Dikerogammarus haemobaphes. It comes from the Ponto-Caspian Sea region in southern Europe and is most likely transported to the UK in ballast water and via cargo ships. It was first recorded in the UK in 2012, and ever since has been competing with the smaller native species (Gammarus pulex) for space and food.

Jocelyne’s recent article, published in the journal Crustaceana highlights demon shrimp research done on the Thames River in 2015, with Tim Johns at the Environment Agency and Clarke Knight in the Geography Department at Oxford.

Amelia Charles, a student on the Department’s Postgraduate Certificate in Ecological Survey Techniques, is continuing the research and examining the extent to which river and canal boats might be vectors of transport for demon shrimps. Jocelyne and Amelia begin field work along the Kennet and Cherwell Rivers in April 2017.

Dr Jocyelyn Hughes and Amelia Charles, a student of the Postgraduate Certificate in Ecological Survey Techniques course, surveying the Thames.

A global problem
The River Thames is currently one of the world’s most highly invaded freshwater ecosystems. Favourable climate, habitat overlap, and efficiencies in global trade have facilitated colonization. Invaders arrive in any number of ways: in ships’ ballast water, on ornamental plants and animals, and on aquatic equipment such as boats and fishing gear.

The Thames demon shrimp invasion is part of a worldwide issue: freshwater ecosystems globally are experiencing ecological change due in part to increases in non-native species.

The invaders’ effect
While it’s too early to know exactly what the impact will be, it’s likely that the demon shrimp will: a) proliferate in the absence of native predators; b) replace native shrimp species; c) spread across UK river catchments and water bodies; d) have economic impacts where they have proliferated in water infrastructure such as sewage systems, and water treatment works.

Jocelyne said, ‘Our research with Clarke Knight and Tim Johns has shown that demon shrimp have spread throughout the Thames catchment but are mostly in the main Thames water channel and not in the headwater streams – but this may just be a matter of time. We didn’t find them co-existing with native shrimp species, Gammarus pulex, which favour gravel stream beds. We found demon shrimps preferred vegetated habitats with fine silt.’

The original 2015 research (in Crustaceana) is being followed up in 2017 to investigate the role of recreational boats in transporting non-native shrimps along the Thames.

The 2017 research, being done in collaboration with Tim Johns from the Environment Agency, will shed light on biosecurity and what we should be doing to best limit the spread of non-native freshwater species in the UK- this applies to anglers and boaters and all water sport users.

For more information:

A version of this post originally appeared on the Department for Continuing Education website.

Oxford hosts inaugural Foresight4Food workshop

Key players meet in Oxford to explore the use of foresight and scenario analysis in the global food system.

 The global food system is under pressure. Demand for food is growing at the same time as natural resources are being depleted. Climate change risks lower crop yields and unpredictable droughts, natural disasters and disease outbreaks that can disrupt food supply. Some two billion people still suffer poor health from low nutrient intake while changing consumption and exercise patterns are leading to obesity problems with dire implications for health and national budgets.

On March 22-23 leading international players gathered in Oxford to explore how foresight and scenario analysis for the global food system could be improved. The meeting resulted in an agreement on the need for more coordination and collaboration across on going work and better stakeholder engagement activities across all players. A small team will take a number of action items forward to develop the Foresight4Food initiative further.

Foresight is a key tool that governments, business and civil society can use to better understand future risks and the opportunities and to adapt – before crises hit.

Yet, as the workshop concluded, current foresight efforts are fragmented and the science of foresight needs to be better connected with societal debate and policy dialogue to drive change.

Dr John Ingram, the Food Systems Programme Leader at the Environmental Change Institute, University of Oxford, said that “this was a very valuable and timely meeting, expressing a clear need for better coordination and integration on both foresight development and outreach”.

Central to the discussion was a food systems perspective. This means looking at food issues across the entire supply chain from production to consumption as well as the connections between environmental, health and economic outcomes. It also looks at food issues in both the developed and developing world. Food is a “nexus” issue that connects across critical global challenges of reducing poverty, improving health, tackling and responding to climate change, protecting biodiversity and managing water scarcity.

Consequently improved foresight for the global food system will be critical to achieving the Sustainable Development Goals, in particular Goal Two (end hunger, achieve food security and improved nutrition, and promote sustainable agriculture).

The event was hosted by the Environmental Change Institute and the Oxford Martin School and organized in collaboration with the Food and Agriculture Organisation (FAO), the International Food Policy Research Institute. Funding to support the event is provided by the Australian Centre for International Agricultural Research (ACIAR), Oxford University through the UK Biotechnology and Biological Sciences Research Council, and the Cooperative Group on International Agricultural Research Program on Policies, Institutions, and Markets (PIM).

Organisations at the meeting agreed to ongoing collaboration to help develop a collaborative “foresight4food” initiative. This will provide mechanisms for greater scientific collaboration as well as for improved communication and engagement process that can support global, regional and national policy dialogue.

“This was a very valuable and timely meeting, expressing a clear need for better coordination and integration on both foresight development and outreach”.

Dr John Ingram, Leader of Food Research, ECI.

A version of this post originally appeared on the Environmental Change Institute website.

Unifying scientific disciplines to solve emerging membrane filtration challenges

Mathematicians and engineers join forces to identify and tackle the pressing issues that are limiting future advances in membrane science.

The Royal Society recently convened experts from around the world to discuss emerging membrane filtration challenges at a workshop held at the Kavli Royal Society International Centre, Chicheley Hall.

The workshop, led by Ian Griffiths, Senior Research Fellow at Oxford University’s Mathematical Institute, with Sourav Mondal (Oxford) and Davide Mattia (University of Bath), considered recent advances in membrane design, fabrication, and their use in filtration technologies. It provided a forum to address problems in filtration science that demand collaboration in experimentation and field testing, microscale theories (molecular dynamics), and macroscale (continuum) theories.

Experts from the UK, Canada, Germany, Israel, Italy, Saudi Arabia and the USA, explored 6 primary topics during the workshop: 1) new membranes for the future; 2) molecular simulations; 3) process modelling; 4) membrane characterization; 5) porosity-graded filters; and 6) fluid transport modelling.

The workshop fostered many fruitful discussions, with a number of new international collaborations emerging from these. These projects are employing state-of-the-art modelling, computational techniques, and experiments to understand how membrane performance can be enhanced and new membranes can be designed for targeted separation tasks.

Ian Griffiths is a Royal Society University Research Fellow whose research agenda concerns 21st century fluid dynamical challenges in water purification. Ian’s research focuses on developing mathematical models that enable improvements in current water purification techniques and assist in developing new filtration technologies. Ian currently has a collaboration with IIT Kharagpur developing mathematical models for arsenic-removal filters, funded through the Global Challenges Research Fund (GCRF) and will continue this work through support from the Royal Society Challenge Grants. You can find out more about the research taking place in his group here.

Tropical rainfall over the last two millennia: evidence for a low-latitude hydrologic seesaw

Researchers at Earth Sciences shed light on the movement of the Intertropical Convergence Zone (ITCZ) over the past 2000 years using paleoclimate techniques.

Precipitation in tropical regions is governed by the Intertropical Convergence Zone (ITCZ), a band of high rainfall encircling the globe near the equator. The ITCZ migrates seasonally between the hemispheres, following the thermal equator of the Earth. In this study, we used a number of published high resolution and precisely dated paleoclimate reconstructions distributed across the tropics and subtropics of the globe and covering the last 2000 years. The reconstructions are extracted from stalagmites, lake records, ice cores, and tree rings. We focused on records that reflect changes in ITCZ-driven precipitation, to track past changes in this important driver of low-latitude climate.

We find that changes in global temperature gradients caused the ITCZ to migrate South for prolonged periods of time, most notably during the Little Ice Age (ca. 1300-1800 AD), where the Northern Hemisphere tropics became drier, while the Southern Hemisphere experienced wetter conditions. This disturbance in tropical atmospheric circulation patterns can be tracked up to the mid-latitudes, where changes in the North Atlantic Oscillation (NAO) are apparent at the same time.

Similar observations have previously been made over glacial-interglacial cycles and Dansgaard-Oeschger events, when cooling of the Northern Hemisphere during full glacial conditions and Heinrich events pushed the ITCZ southward, while warmer interglacials were characterized by a more northerly position of the tropical rainfall belt. Our results however show that even much smaller changes in global temperatures can trigger a notable shift in the distribution of low latitude rainfall patterns. The global extent of this seesaw pattern highlights the importance of tropical energy fluxes on climate.

Postdoc Franziska Lechleitner, first author on the paper, describes her work: “We did extensive fieldwork at Yok Balum Cave in southern Belize over the past seven years, to study and characterize the evolution of tropical Atlantic rainfall patterns and climate over the last 2000 years. Apart from the collection of stalagmite samples, we installed an extensive network of monitoring equipment, to understand how weather conditions affect the cave, and collected water samples from inside the cave and the overlying soil, to identify processes occurring between the surface and the cave.

Researchers crossing a stream in Belize during the rainy season.

“The cave is located right at the northern extent of the present-day ITCZ and therefore is extremely sensitive to even small shifts in the latter, as we found in a previous study (Ridley et al., 2015, Nature Geoscience).”

Paper: Tropical rainfall over the last two millennia: evidence for a low-latitude hydrologic seesaw, by Franziska A. Lechleitner, Sebastian F. M. Breitenbach, Kira Rehfeld, Harriet E. Ridley, Yemane Asmerom, Keith M. Prufer, Norbert Marwan, Bedartha Goswami, Douglas J. Kennett, Valorie V. Aquino, Victor Polyak, Gerald H. Haug, Timothy I. Eglinton & James U. L. Baldini, is published in Scientific Reports.

This post was originally published on the Earth Sciences website.

Rising to the water challenge

Since its inception in 2011, the Oxford Water Network (OWN) has helped cement Oxford University’s reputation as a global centre for excellence in water research and teaching. Now in its 6th year, OWN looks to build on this success and take the network to the next level.

A glance at today’s headlines provides a stark reminder of the many water-related problems we face: drought in East Africa; floods in Peru and Colombia; conflict around the Tabqa Dam on the Euphrates; concerns regarding drinking water safety in the US. These stories highlight the often complex and multi-dimensional nature of the water security challenges facing decision makers globally: it is problems such as these that prompted the creation of the Oxford Water Network (OWN) in 2011.

OWN is an initiative that seeks to leverage the University of Oxford’s diverse research expertise to tackle the growing threat of water insecurity worldwide. OWN comprises an immediate network of over 130 Oxford University research and support staff, spread across the natural, social and engineering sciences. Beyond the University, OWN maintains links with external partners drawn from the academic, policy, civil society and business communities.

Since its creation, OWN has helped its members secure a number of major funding awards. Notable examples include REACH – a global research programme seeking to improve water security for poor people in Asia and Africa; MaRIUS – a project exploring the management of droughts and water scarcity in the UK; and Gro for GooD – a project seeking to develop a groundwater risk management approach to support development in Kenya.

OWN events provide a forum to share ideas and build the relationships necessary to realise interdisciplinary collaboration. We host seminar series, workshops and conferences. In 2012 and 2015, OWN convened two, agenda-setting, international water security conferences, which brought together leading thinkers and practitioners from government, enterprise, civil society and academia to advance and debate a risk-based analysis of water security. The first of these events gave rise to a themed issue on water security in the Philosophical Transactions of the Royal Society.

As OWN embarks on its next chapter, we are taking time to consider how we can build on our success to date. As part of this process, we are seeking to initiate a period of consultation with our members to better understand how we can support their research, improve its impact, and ultimately harness the full potential of the network to address the many water challenges we face.

If you have any thoughts as to how we can take OWN to the next level, contact me at alastair.strickland@ouce.ox.ac.uk. You can find out more about the Oxford Water Network at www.water.ox.ac.uk or by subscribing to our monthly newsletter.