Dr. Elizabeth S. Jeffers
As a James Martin Research Fellow, I investigate how ecosystems respond to a number of environmental changes. I use palaeoecological data including fossil pollen, chironomids, charcoal, dung fungal spores and stable isotopes along with mechanistic modelling techniques to reconstruct changes in ecosystem structure and function over time. The overarching aim of my research is to use palaeoecological analyses to address pressing ecological questions, as detailed in the current projects below.
Is nitrogen (N) availability to plants increasing or decreasing over time? Global environmental changes such as N deposition, climate warming and increasing atmospheric CO2 concentrations are driving complex changes in N cycling within ecosystems. The Progressive Nitrogen Limitation (PNL) hypothesis posits that as atmospheric CO2 concentrations increase, plants will become increasingly nitrogen-limited; this will have strong negative impacts on primary productivity of ecosystems worldwide. A global synthesis of stable nitrogen isotope (δ15N) records has been conducted in order to test the progressive nitrogen limitation hypothesis for both recent and ancient periods of increasing atmospheric CO2. This project is being conducted in collaboration with Kendra McLauchlan, Joseph Williams and Joseph Craine at Kansas State University.
Palaeo-ecosystem service research
How might the provision of important ecosystem services change over time given global and local environmental changes? There are a number of ways in which palaeoecological data have already been used to understand the provision of ecosystem services over time; yet they are largely missing from the international and national ecosystem assessments, which aim to answer this important question. Palaeoecological data are available at the high spatial and temporal resolution needed to support policy making for the sustainable management of biodiversity and ecosystem services. Incorporating palaeoecological research into ecosystem assessments and landscape planning for ecosystem service provision requires coordinated efforts to (1) promote the use and interpretation of new palaeo-proxies; (2) develop modelling techniques for translating raw palaeoecological data into the currencies used by ecosystem managers; and (3) make the information collected in palaeo-databases accessible and useful for landscape planning tools. This project was kick-started with a workshop entitled Landscape Planning for the Future, funded by the Oxford Martin School and PAGES.
Palaeo-population and community ecology
How does global and local environmental change affect plant populations, communities and ecosystem functioning? Palaeoecological data allow us to extend our ecological “observations” to millennia and beyond. This long-term view offers an essential perspective on how ecosystems change in response to both slow and fast drivers. Growth in the number of palaeoecological proxies available for environmental reconstructions and the development of novel modelling methods enables us to test hypotheses about the mechanisms underlying long-term ecosystem changes. With Mike Bonsall, I use statistical modelling to answer questions such as how do individual populations contribute to ecosystem functioning and how resilient are these links between populations and ecosystem functions to perturbations and long-term shifts in the environment?
Roughly 12% of the earth’s land area is currently protected from development; how can we develop the remaining 88% while protecting biodiversity and key ecosystem processes? The LEFT is a simple and transparent decision support tool that aims to help businesses make more informed choices about where to place facilities with minimal ecological impacts. With Kathy Willis and Carolina Tovar, I developed the LEFT, which uses readily available, web-based spatial data and existing algorithms to assess differences in ecological value across a landscape. My future work on the LEFT is the development of a management layer that will address two important questions: (1) what is the expected loss in ecological value for a given proposed development strategy and (2) what is the optimal placement of proposed facilities in order to minimize the loss in ecological value? This decision support layer will be applied to the new, high resolution (30m) version of the LEFT that is being developed by other members of the Biodiversity Institute.
I completed my D.Phil. entitled “The dynamics of ecosystem processes over successional time scales: plant population responses to environmental change and their feedback effects on ecosystem functioning” (supervised by Kathy J. Willis, Michael B. Bonsall and Steve Brooks) in the Oxford Long-Term Ecology Laboratory (LTEL) within the School of Geography & the Environment. I came to the LTEL because I wanted to investigate new methods of modelling the palaeoecological record in order to improve our understanding of long-term ecosystem dynamics and to support conservation and natural resource management decision making.
I hold a Masters of Arts in Geography & Environmental Engineering and a Masters in Public Policy from the Johns Hopkins University and a Bachelors of Arts in Political Science from the University of Colorado, Boulder. I have held a variety of environmental policy research positions, including work at the Bureau of Land Management (US Government), the International Centre for Environmental Finance (non-profit consulting) and Coast Alliance (non-profit advocacy).
I teach a masters-level elective course entitled “Ecosystem Valuation” in the School of Geography and the Environment. Additionally, I have led the statistics tutorials for first year undergraduate students reading Geography at the University of Oxford. At the Johns Hopkins University, I was a teaching assistant for the Institute for Policy Studies master's program, which involved tutoring graduate students in policy analysis methods, effective writing, teamwork and desktop mapping.
Tel.: +44 1865 281 326
Click here for CV
Syllabus for Ecosystem Valuation MSc Elective Course
Jeffers, E.S., M.B. Bonsall, C.A. Froyd, S.J. Brooks and K.J. Willis (in preparation) Life history traits as indicators of shifts in ecosystem functioning given a changing climate.
Jeffers, E.S., S. Nogue and K.J. Willis (in preparation) Conservation of ecosystem function: Using palaeoecological data to understand the processes that support ecosystem service provision.
McLauchlan, K.K., J. J. Williams, J. M. Craine and E.S. Jeffers (2013) Changes in nitrogen cycling during the Holocene epoch. Nature, 495: 352-355.
Jeffers, E.S. (2013) Handbook for opening the vault: a helpful guide to using and interpreting paleontological data. Frontiers in Biogeography 5(1): 13-15.
Willis, K.J., E.S. Jeffers, C. Tovar, P. Long, N. Caithness, et al. (2012)Determining the ecological footprint of industrial development on landscapes beyond protected areas. Biological Conservation 147(1): 3-12.
Jeffers, E.S., M.B. Bonsall, J. Watson and K.J. Willis (2012) Climate change impacts on ecosystem functioning: evidence from an Empetrum heathland. New Phytologist 193 (1): 150-164.
Jeffers, E.S., M.B. Bonsall, S.J. Brooks and K.J. Willis (2011) Abrupt environmental changes drive shifts in plant-plant interaction outcomes. Journal of Ecology, 99(4), 1063-1070.
Jeffers, E.S., M.B. Bonsall and K.J. Willis (2011) Stability in ecosystem functioning across a climatic threshold and contrasting forest regimes. PLoS ONE, 6(1), e16134.
Combs, D., E. S. Pazdernik (Jeffers) and J. Savitz. (2002) Mission Possible II: State progress in controlling runoff on the coast. Coast Alliance, Washington, DC.
E.S. Jeffers (2012) “Mechanistic modelling of palaeoecological data,” IGBP/PAGES Biodiversity Theme Workshop, University of Oxford.
E.S. Jeffers, M.B. Bonsall, J.E. Watson and K.J. Willis (2011) "Identifying plant-environment feedback mechanisms from palaeoecological data," British Ecological Society Annual Meeting, Sheffield, UK.
Willis, K.J., E.S. Jeffers, C. Tovar, M.G.D. Smit, C. Collin-Hansen and J. Weissenberger (2011) “Assessing the physical impact (footprint) of industrial development on landscapes beyond protected areas,” Society of Petroleum Engineers Health, Safety and Environment Meeting, Austria, Vienna.
Jeffers, E.S., M.B. Bonsall and K.J. Willis (2010) “Fire and flammability characteristics in plant community dynamics: Inferring feedback mechanisms from the palaeoecological record,” Ecological Society of America Annual Meeting, Pittsburgh, PA.
Jeffers, E.S. (2010) “Using ordinary differential equation models to represent fire and temperature dynamics from palaeoecological data,” Mathematical Geosciences Workshop, Mathematical Institute, University of Oxford.
Jeffers, E.S., M.B. Bonsall and K.J. Willis (2007), “Model-fitting the fossil record: Evaluating multiple drivers of vegetation change,” British Ecological Society Annual Meeting, Glasgow, UK.
Jeffers, E.S. (2006) “Fossil pollen and stable isotopes: Modelling vegetation dynamics and nitrogen availability,” Wolfson Symposium on Evolutionary Ecology, University of Oxford.