News from a scientific frontier: the complexity of field-to-river connectivity in the Rother catchment

Researchers from the University of Oxford’s Environmental Change Institute explore the dynamics of soil erosion and river sedimentation in a catchment in South East England.

Picture this: the River Rother flowing eastward through the High Weald on its way to the English Channel. An archetypal lowland scene in the English South Downs National Park, with a peaceful river winding sedately through a mosaic of woodland, farmsteads and villages, all set against a backdrop of green rolling hills.

Rother Catchment. SMART (Sediment and Mitigation Actions for the River Rother) project.

But things are not actually as tranquil and well-ordered as they might seem. The beauty of the view belies the poor ecological condition along much of the river. High sediment load is smothering the riverbed gravels. This is thought to be exacerbating pollution and degradation of the riverine ecosystem, threatening the ‘good ecological status’ required by the European Water Framework Directive, and increasing the costs of producing drinking water: a particular concern of Southern Water.

There is much debate as to the proportion of sediment generated by erosion from arable fields, versus that caused by natural erosion of the bed and banks of the river. In part, this is because it is far from easy to determine the routes by which runoff and sediment leaves eroding fields and reaches the river. The connectivity of runoff and sediment flows is difficult to map and even more difficult to capture in a quantitative model. This is a highly complex research frontier1 – one where science struggles to advance.

Ephemeral gully, Rotherbridge, Feb 2014. SMART (Sediment and Mitigation Actions for the River Rother) project.

For a number of years, the Environmental Change Institute’s Professor John Boardman, and a team of collaborators, have been working on field-to-river connectivity in the Rother catchment. For news from this scientific frontier, come along to a lunchtime seminar hosted by Oxford Water Network at the School of Geography and the Environment. Professor Boardman will present alongside ECI collaborator, Dr Dave Favis-Mortlock, at 1 pm on Monday November 13 in the Gilbert Room.

1. ‘There are three great frontiers in science: the very big, the very small, and the very complex.’ Rees, M. (2002) Our Cosmic Habitat. Weidenfeld and Nicolson, London, pp180.

References

About the researchers

Professor John Boardman
Emeritus Professor

John Boardman is a geomorphologist educated at the Universities of Keele (BA and DSc) and London (BSc and PhD). John retired from ECI in September 2008 and from his positions as Deputy Director of the ECI, Director of the MSc in Environmental Change and Management. He is now an Emeritus Professor at the ECI and continues working on land degradation issues, particularly in the Karoo, South Africa. He has published over 160 papers mainly on land degradation and has edited several books: Soils and Quaternary Landscape Evolution (Wiley 1985), Periglacial Processes and Landforms in Britain and Ireland (CUP 1987), Soil Erosion on Agricultural Land (Wiley 1990), Modelling Soil Erosion by Water (Springer 1998) and Soil Erosion in Europe (Wiley 2006). John continues to work on soil erosion in southern England and also on land degradation in South Africa.

Dr David Favis-Mortlock
Honorary Research Associate

Dave Favis-Mortlock is a geomorphological modeller whose research is focused on soil erosion by water and (more recently) long-term coastal change. Particular interests include self-organization of complex systems, modelling the impacts of changing climate and land use, and model evaluation.

He obtained an undergraduate degree in Environmental Sciences from Lancaster University. Then following a period in commercial computing and as a musician, he began doctoral research at the University of Brighton, co-publishing the first studies on the impacts of future climate change on erosion. In 1992, Dave moved to Oxford to begin work as a researcher at what was then called the Environmental Change Unit. Following ten years as a lecturer at Queen’s University Belfast, in 2011 he returned to the Environmental Change Institute. Dave is also a jazz violinist.