Dr Elizabeth Jeffers
How does climate change affect plant chemistry? And what are the cascading effects on nutrient cycling and ecological communities? These are the key questions that guide my current research. To answer them, I employ a range of palaeoecological, dendroecological and neo-ecological methods to measure changes in plant growth and chemical composition over time at seasonal to millennial time scales. These long-term records fill a major observational gap in ecosystem ecology. I then apply statistical modelling techniques to these time series to uncover new insights into the causes and consequences of ecosystem dynamics.
I convene the Ecology of Terrestrial Ecosystems third year option course and teach biogeochemical cycling for first year students in Biology. I am also the Department’s Director of Graduate Studies and serve on the editorial boards of Ecology Letters and the Journal of Ecology.
I am recruiting for collaborative D.Phil. projects with the Centre for Ecology & Hydrology and the Rutherford Appleton Laboratory. Project descriptions are available on the NERC DTP website:
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Resilience: nitrogen limitation, mycorrhiza and long-term palaeoecological plant-nutrient dynamics.
January 2020|Journal article|Biology lettersEcosystem dynamics are driven by both biotic and abiotic processes, and perturbations can push ecosystems into novel dynamical regimes. Plant-plant, plant-soil and mycorrhizal associations all affect plant ecosystem dynamics; however, the direction and magnitude of these effects vary by context and their contribution to ecosystem resilience over long time periods remains unknown. Here, using a mathematical framework, we investigate the effects of plant feedbacks and mycorrhiza on plant-nutrient interactions. We show evidence for strong nutrient controlled feedbacks, moderation by mycorrhiza and influence on ecological resilience. We use this model to investigate the resilience of a longitudinal palaeoecological birch-<i>δ</i><sup>15</sup>N interaction to plant-soil feedbacks and mycorrhizal associations. The birch-<i>δ</i><sup>15</sup>N system demonstrated high levels of resilience. Mycorrhiza were predicted to increase resilience by supporting plant-nitrogen uptake and immobilizing excess nitrogen; in contrast, long-term enrichment in available nitrogen by plant-soil feedbacks is expected to decrease ecological resilience.Mycorrhizae, Plants, Nitrogen, Soil, Ecosystem, Nutrients -
Machine learning and artificial intelligence to aid climate change research and preparedness
December 2019|Journal article|ENVIRONMENTAL RESEARCH LETTERSclimate change, global warming, extreme weather, drought, artificial intelligence, machine learning, climate simulations -
Plant controls on Late Quaternary whole ecosystem structure and function.
June 2018|Journal article|Ecology lettersPlants and animals influence biomass production and nutrient cycling in terrestrial ecosystems; however, their relative importance remains unclear. We assessed the extent to which mega-herbivore species controlled plant community composition and nutrient cycling, relative to other factors during and after the Late Quaternary extinction event in Britain and Ireland, when two-thirds of the region's mega-herbivore species went extinct. Warmer temperatures, plant-soil and plant-plant interactions, and reduced burning contributed to the expansion of woody plants and declining nitrogen availability in our five study ecosystems. Shrub biomass was consistently one of the strongest predictors of ecosystem change, equalling or exceeding the effects of other biotic and abiotic factors. In contrast, there was relatively little evidence for mega-herbivore control on plant community composition and nitrogen availability. The ability of plants to determine the fate of terrestrial ecosystems during periods of global environmental change may therefore be greater than previously thought.Animals, Plants, Nitrogen, Soil, Ecosystem, Biomass, Ireland, Herbivory -
What makes a terrestrial ecosystem resilient?
March 2018|Journal article|Science (New York, N.Y.)Conservation of Natural Resources, Ecosystem -
Shrub growth and expansion in the Arctic tundra: an assessment of controlling factors using an evidence-based approach
August 2017|Journal article|ENVIRONMENTAL RESEARCH LETTERSarctic, shrub, systematic approach, shrub growth, shrub expansion, global change -
Remote assessment of locally important ecological features across landscapes: how representative of reality?
July 2015|Journal article|Ecological applications: a publication of the Ecological Society of AmericaThe local ecological footprinting tool (LEFT) uses globally available databases, modeling, and algorithms to, remotely assess locally important ecological features across landscapes based on five criteria: biodiversity (beta-diversity), vulnerability (threatened species), fragmentation, connectivity, and resilience. This approach can be applied to terrestrial landscapes at a 300-m resolution within a given target area. Input is minimal (latitude and longitude) and output is a computer-generated report and series of maps that both individually and synthetically depict the relative value of each ecological criteria. A key question for any such tool, however, is how representative is the remotely obtained output compared to what is on the ground. Here, we present the results from comparing remotely- vs. field-generated outputs from the LEFT tool on two distinct study areas for beta-diversity and distribution of threatened species (vulnerability), the two fields computed by LEFT for which such an approach is feasible. The comparison method consists of a multivariate measure of similarity between two fields based on discrete wavelet transforms, and reveals consistent agreement across a wide range of spatial scales. These results suggest that remote assessment tools such as LEFT hold great potential for determining key ecological features across landscapes and for being utilized in preplanning biodiversity assessment tools.cities, spacecraft, SBTMR, biodiversity, databases, factual, uncertainty, environmental monitoring -
The role of palaeoecological records in assessing ecosystem services
March 2015|Journal article|Quaternary Science Reviews© 2014 Elsevier Ltd. Biological conservation and environmental management are increasingly focussing on the preservation and restoration of ecosystem services (i.e. the benefits that humans receive from the natural functioning of healthy ecosystems). Over the past decade there has been a rapid increase in the number of palaeoecological studies that have contributed to conservation of biodiversity and management of ecosystem processes; however, there are relatively few instances in which attempts have been made to estimate the continuity of ecosystem goods and services over time. How resistant is an ecosystem service to environmental perturbations? And, if damaged, how long it does it take an ecosystem service to recover? Both questions are highly relevant to conservation and management of landscapes that are important for ecosystem service provision and require an in-depth understanding of the way ecosystems function in space and time. An understanding of time is particularly relevant for those ecosystem services - be they supporting, provisioning, regulating or cultural services that involve processes that vary over a decadal (or longer) timeframe. Most trees, for example, have generation times >50 years. Understanding the response of forested ecosystems to environmental perturbations and therefore the continuity of the ecosystem services they provide for human well-being - be it for example, carbon draw-down (regulating service) or timber (provisioning service) - requires datasets that reflect the typical replacement rates in these systems and the lifecycle of processes that alter their trajectories of change. Therefore, data are required that span decadal to millennial time-scales. Very rarely, however, is this information available from neo-ecological datasets and in many ecosystem service assessments, this lack of a temporal record is acknowledged as a significant information gap.This review aims to address this knowledge gap by examining the type and nature of palaeoecological datasets that might be critical to assessing the persistence of ecosystem services across a variety of time scales. Specifically we examine the types of palaeoecological records that can inform on the dynamics of ecosystem processes and services over time - and their response to complex environmental changes. We focus on three key areas: a) exploring the suitability of palaeoecological records for examining variability in space and time of ecosystem processes; b) using palaeoecological data to determine the resilience and persistence of ecosystem services and goods over time in response to drivers of change; and c) how best to translate raw palaeoecological data into the relevant currencies required for ecosystem service assessments. -
Social-ecological systems in the Anthropocene: The need for integrating social and biophysical records at regional scales
January 2015|Journal article|Anthropocene Review© The Author(s) 2015. Understanding social-ecological system dynamics is a major research priority for sustainable management of landscapes, ecosystems and resources. But the lack of multi-decadal records represents an important gap in information that hinders the development of the research agenda. Without improved information on the long-term and complex interactions between causal factors and responses, it will be difficult to answer key questions about trends, rates of change, tipping points, safe operating spaces and pre-impact conditions. Where available long- term monitored records are too short or lacking, palaeoenvironmental sciences may provide continuous multi-decadal records for an array of ecosystem states, processes and services. Combining these records with conventional sources of historical information from instrumental monitoring records, official statistics and enumerations, remote sensing, archival documents, cartography and archaeology produces an evolutionary framework for reconstructing integrated regional histories. We demonstrate the integrated approach with published case studies from Australia, China, Europe and North America.
E: | elizabeth.jeffers@zoo.ox.ac.uk |
T: | 01865 (2) 71114 |
Oxford Long Term Ecology website |