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DAVID JOHN
MILAN

Geography - United Kingdom

Research topics

PROJECT

Understanding braided rivers for improved sediment management and biodiversity in a changing climate

 

Braided rivers are characteristic of many temperate piedmont and alpine-valley environments where they are found in locations with high sediment supply and a flow regime often controlled by glacial meltwater cycles. Pristine braided rivers are characterized by a shifting mosaic of channels, ponds, bars, and islands, fed with flood pulses to create diverse habitats. A diverse flora and fauna colonize these habitats, adapted to their dynamic character, including rare and endangered species. Unfortunately, many braided rivers have been degraded by flow regulation or channelization. Restoration of braided rivers presents many challenges, and needs to address not only habitat conservation, but also enhanced flood risk caused by climate change. As glaciers retreat in a warmer world, proglacial zones are revealing vast quantities of unconsolidated sediment available to rivers for transport. Climate change is also increasing the probability of intense precipitation events causing flash flooding. The impact of changing sediment loads and flood magnitudes upon braided river biodiversity is unknown. Measurement of sediment transport in braided rivers is also difficult due to their complex morphodynamics, hindering the validation of models used for flood management. Restoration of braided rivers also faces public perception issues: the presence of gravel bars, are often viewed as being unattractive, and a possible cause of flooding, and the public are often unaware of their high biodiversity value. This research brings together earth scientists, social scientists and ecologists, in a project that aims to:

  1. Develop an approach to better estimate sediment flux in braided rivers;
  2. Review the impacts of climate change upon braided river biodiversity, and explore their current status globally; and
  3. Improve public perceptions of braided rivers

Activities / Resume

BIOGRAPHY

David Milan is a Senior Lecturer in Physical Geography at the University of Hull, UK. His research is focused at the interface between fluvial geomorphology and freshwater ecology. It aims to tackle issues related to the effects of changing flow and sediment supply regimes upon river habitat quality, in response to climate change and human activities.
David Milan has a particular interest in the application of new technologies to address river science problems. His work using terrestrial LiDAR has demonstrated how the technology can be used to provide improved assessments of bed roughness and grain-size at the reach-scale, assess rapid morphological change in dynamic proglacial rivers, and map river habitat.
 

BIBLIOGRAPHY

  • Milan, D.J., Tooth, S., Heritage, G.L., 2020. Topographic, hydraulic and vegetative controls on bar and island development in mixed bedrock-alluvial multichanneled, dryland rivers. Water Resources Research.
  • Schwendel, A., Milan, D.J. 2020. Terrestrial structure-from-motion: spatial error analysis of roughness and morphology. Geomorphology, 350.
  • Entwistle, N., Heritage, G., Milan, D. 2019. Ecohydraulic modelling of anabranching rivers. River Research and Applications, 35, 353-364.
  • Heritage, G.L., Entwistle, N., Milan, D.J., Tooth, S. 2019. Quantifying and contextualising cyclone-driven, extreme flood magnitudes in bedrock-influenced dryland rivers. Advances in Water Research. 123, 145-159.
  • Entwistle, N., Heritage, G.L., Milan, D.J. 2018. Recent Remote Sensing Applications for Hydro and Morphodynamic Monitoring and Modelling. Earth Surface Processes and Landforms, 43, 2283-2291.
  • Entwistle N, Heritage G, Milan D. 2018. Flood energy dissipation in anabranching channels. River Research & Applications, 34 (7), 709-720.
  • Milan, D.J., Heritage, G.L., Tooth, S., Entwistle, N. 2018. Morphodynamics of bedrock-influenced dryland rivers during extreme floods: insights from the Kruger National Park, South Africa, Geological Society of America Bulletin. 130, 1825-1841.
  • Milan, D.J. 2017. Controls on spatial and temporal variations in sand delivery to salmonid spawning riffles. Hydrological Processes, 31, 2179-2195.
  • Milan, D.J. & Large, A.R.G. 2014. Magnetic tracing of sand over pool-riffle morphology. Catena, 115, 134-149.
  • Milan, D.J. 2013. Sediment routing hypothesis for pool-riffle maintenance. Earth Surface Processes and Landforms, 38, 1623-1641.
  • Milan, D.J. 2013. Virtual velocity of tracers in a gravel-bed river using size-based competence duration. Geomorphology, 198, 107-114.
  • Milan, D.J. & Heritage, G.L. 2012. LiDAR and ADCP use in gravel bed rivers: Advances since GBR6. In Church, M., Biron, P. and Roy, A. (eds) Gravel-bed rivers: Processes, Tools, Environments, John Wiley & Sons, Chichester, pp286-302.
  • Milan, D.J. 2012. Geomorphic impact and system recovery following an extreme flood in an upland stream: Thinhope Burn, northern England, UK. Geomorphology, 138(1), 319-328.
  • Milan, D.J., Heritage, G.L., Large, A.R.G., Fuller, I. D. 2011. Filtering spatial error from DEMs; implications for morphological change estimation. Geomorphology, 125, 160-171.
  • Milan, D.J., Heritage, G.L., Large, A.R.G., Entwistle, N. 2010. Mapping hydraulic biotopes using terrestrial laser scan data of water surface properties. Earth Surface Processes & Landforms, 35, 918-931.
  • Heritage, G.L., Milan, D.J., G.L., Large, A.R.G., and Fuller, I. 2009. Influence of survey strategy and interpolation model upon DEM quality. Geomorphology, 112, 334-344.
  • Heritage, G. L., Milan, D.J. 2009. Terrestrial laser scanning of grain roughness in a gravel-bed river, Geomorphology, 113, 4-11.
  • Milan, D.J., Heritage, G.L., Hetherington, D. 2007. Application of a 3D laser scanner in the assessment of erosion and deposition volumes in a proglacial river. Earth Surface Processes & Landforms, 32(11), 1657-1674.