Dr Elizabeth Follett
Royal Academy of Engineering-Sêr Cymru Research Fellow
- follette1@cardiff.ac.uk
- Room S/1.42, Queen's Buildings - South Building, 5 The Parade, Newport Road, Cardiff, CF24 3AA
- Available for postgraduate supervision
Overview
My research demonstrates the physical processes by which wood jams and vegetation affect flow, particle transport, and ecological health. I develop physically-based representations of these processes for modelling and design guidance using a combination of flume experiments, theoretical development and field observations, in order to improve the design and assessment of natural flood management projects and restoration interventions.
Publications
2021
- Follett, E., Schalko, I. and Nepf, H. 2021. Logjams with a lower gap: Backwater rise and flow distribution beneath and through logjam predicted by two-box momentum balance. Geophysical Research Letters 48(16), article number: e2021GL094279. (10.1029/2021GL094279)
2020
- Follett, E., Schalko, I. and Nepf, H. 2020. Momentum and energy predict the Backwater rise generated by a large wood jam. Geophysical Research Letters 47(17), article number: e2020GL089346. (10.1029/2020GL089346)
2019
- Follett, E., Hays, C. G. and Nepf, H. 2019. Canopy-mediated hydrodynamics contributes to greater allelic richness in seeds produced higher in meadows of the coastal eelgrass Zostera marina. Frontiers in Marine Science 6, article number: 8. (10.3389/fmars.2019.00008)
2018
- Follett, E. and Nepf, H. 2018. Particle retention in a submerged meadow and its variation near the leading edge. Estuaries and Coasts 41(3), pp. 724-733. (10.1007/s12237-017-0305-3)
2017
- Kelly, P. T. et al. 2017. Ecological dissertations in the aquatic sciences: an effective networking and professional development opportunity for early career aquatic scientists. Limnology and Oceanography Bulletin 26(2), pp. 25-30. (10.1002/lob.10180)
2016
- Follett, E., Chamecki, M. and Nepf, H. 2016. Evaluation of a random displacement model for predicting particle escape from canopies using a simple eddy diffusivity model. Agricultural and Forest Meteorology 224, pp. 40-48. (10.1016/j.agrformet.2016.04.004)
2014
- Pan, Y., Follett, E., Chamecki, M. and Nepf, H. 2014. Strong and weak, unsteady reconfiguration and its impact on turbulence structure within plant canopies. Physics of Fluids 26, article number: 105102. (10.1063/1.4898395)
2012
- Follett, E. and Nepf, H. 2012. Sediment patterns near a model patch of reedy emergent vegetation. Geomorphology 179, pp. 141-151. (10.1016/j.geomorph.2012.08.006)
Structure and function of wood jams for natural flood management
Natural flood management practices, including engineered logjam installations, can promote floodwater storage and infiltration in upstream catchments, ehancing sediment storage and ecological resilience. Dr Follett's research considers the effects of engineered log jam installations on stream hydrodynamics and sediment transport in order to accurately assess the implications of natural flood management projects and guide management interventions.
Funding: Royal Academy of Engineering-Sêr Cymru Research Fellowship [2020-2025]
The answer lies in the soil: Environmental resilience in rural Wales
Welsh farmers play a crucial role in sustaining ecosystem services of clean water, air and habitat provision, as well as food production. In addition to pressures to produce food cheaply, farmers are at serious risk due to the negative impacts of climate change, which is already increasing summer storm intensity and sediment runoff. Online and in-person workshops communicated basic mechanisms of sustainable farming actions and collected feedback from farmers on barriers to implementation, key decisionmaking points, and preferences for information delivery. Partnership with NFU Cymru, Nuffield Farming Trust Scholar Ms. Lorna Davis and designer Mrs. Penelope Turnbull, who is developing mosaic sculpture based on farmer-identified tensions and bilingual childrens' art tutorials.
Funding: NERC Wales Showcase 2021 [March-Nov 2021]
WoodJam: Sediment dynamics of instream wood jams and managed installationsIn order to reduce flood damages and prepare for an expected increase in severe floods due to climate change, the EU Water Framework Directive encourages the use of engineered logjams and other natural flood management interventions. It is necessary to consider the effects of channel- spanning engineered log jam installations, which are the most common, on stream hydrodynamics and sediment scour and retention in order to guide management interventions and accurately assess the implications of natural flood management project. This project experimentally investigated the impact of jam geometry and spacing on sediment storage, including development of a method to assess the porosity of a jam without disassembly in partnership with Slow the Flow Shropshire, a DEFRA-designated natural flood management site.
Funding: Marie Skłodowska-Curie Individual Fellowship [2018-2020]
Particle transport in vegetated canopies
The feedbacks between plants, flow, and particle fate shape the size, shape, and resilience of vegetated regions, which provide key ecosystem services to the landscapes in which they reside. Vegetation acts as an ecosystem engineer by creating distinct regions of flow diversion, turbulent mixing, and quiescent flow, dependent upon canopy physical parameters. The density and extent of vegetated canopies alters the canopy mediated flow profile, in turn influencing particle transport. In order to predict the resilience and future growth of vegetation, it is necessary to consider particle transport in light of the canopy-mediated flow environment. Dr Follett's research considers particle fate and transport in emergent and submerged vegetated canopies through laboratory experiments and numerical modeling, connecting transport trends to the physical parameters governing the canopy mediated flow profile, as well as particle size and density.
Funding: U.S. National Science Foundation Grant No. AGS-1005480 (PI Professor Heidi Nepf)
EAR-0738352 (PI Professor Heidi Nepf)
Supervision
I am happy to discuss support of applications for external PhD and postdoctoral funding related to environmental fluid mechanics, vegetated flows, and natural flood management. Currently, I supervise 1 PhD student (start Oct 2021) and PDRA.
Currently, we have an open EPSRC DTP studentship in fluid-structure interaction for logjams placed over a mobile sediment bed, using a combination of flume experiments and numerical modelling (co-I Dr Zhihua Xie). Please see linked advert for additional details.
