Climatic volatility and its impacts on populations and ecosystems

Project Rationale:
Within its projected warmest autumn on record, Sydney experienced its coldest morning in over 20 years during May 2016. This kind of increasing climate volatility, both its variance and temporal sequence (including the breakdown of seasonality), is a ubiquitous prediction of future climate projections1. Current research nevertheless either neglects climate volatility as “background noise” or focuses on its consequences for population dynamics and extinction risk.
Combining modeling and new experiments in a well-established system2, the aim of this project is to test how climatic volatility affects the life cycle of an “ecosystem engineer” species to explore how ecosystem processes might be disrupted. Statistical analysis will assess the transferability of the experimental results in the natural world.
The experiments will focus on the ecosystem impact of different patterns of environmental change, holding the mean environment constant but altering the number of flips between environmental states, the order of those flips and their magnitude. The impact of and recovery from these different environmental sequences will be pivotal to achieve a better understanding how the impacts of climatic volatility scale from population dynamics to ecosystem functioning.

Methodology:
The project will combine laboratory-based experiments with mathematical and statistical modeling, and opportunities for fieldwork. The successful candidate will conduct a range of short (weeks) and long-term (months) experiments in which selected marine invertebrates will be exposed to different environmental regime changes. Over the duration of the experiments, you will quantify changes in species-specific functional effect and response traits including sediment reworking and ventilation activity, which will be mapped to demographic rates such as growth, survival and fertility. The experimental data will be analyzed statistically and embedded in a stochastic life table response experiment3 to quantify the relative influence of stochastic growth rate to contributions within and across environmental states and their temporal pattern. This analysis will identify the key life stages for an ecosystem engineer species that delivers ecosystem functioning, and whether the influence of those stages remain the same in different and changing environments.

Training:
The INSPIRE DTP programme provides comprehensive personal and professional development training alongside extensive opportunities for students to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and industrial/policy partners. The student will be registered at the University of Southampton and hosted in the School of Ocean and Earth Sciences. Specific training will include:
(i) laboratory- and field-based experimental skills in marine ecology, (ii) an understanding of experimental design, (iii) programming and analytical skills in the R environment for statistical computing (iii) understanding of ecological patterns and processes in benthic ecosystems experiencing a variable environment.The student’s transferrable skills will be attractive to a range of academic, governmental and non-governmental organizations. Results will be written up for peer-reviewed journals. Key professional attributes such as scientific writing and oral presentation skills will be developed further and reinforced by presenting research at international conferences and workshops.