PhD StudentshipQuantifying vegetation responses to climate change using isotopic tracersSupervisors: Dr Dominic Hodgson, Dr Pete Convey (BAS, Cambridge) Funding is already secured for this studentship. The NERC award for the 2008-09 year will be £12,940. For more information, see http://www.nerc.ac.uk/funding/available/postgrad/awards/, and for eligibility see http://www.nerc.ac.uk/funding/available/postgrad/eligibility.asp. Antarctic moss banks contain a well-preserved record of individual sub fossil moss species and the overall response of plant communities to past natural, and recent anthropogenically-driven, climate change. An analysis of growth and isotopic proxies will determine past plant community responses to climate change, and enable modelling of future impacts of rapidly warming climates, that is of relevance to scientists and policymakers in both polar regions. The maritime Antarctic has seen one of the most rapid warming rates recorded on Earth over the last 40-50 years as well as changes in precipitation and radiation exposure. These climatic changes are increasingly linked with biological changes in plant growth rates, seasonal patterns of growth, and reproductive success. Signy Island was the site of detailed baseline studies of moss phenology (growth patterns) in the mid 1960's, near to the start of this warming phase and has long term climate data spanning > 50 years. It also has some of the oldest (c. 6000 years) accessible well-preserved moss bank accumulations in the Antarctic. After a further 40-50 years of regional warming since these baseline studies, this studentship will: (1) Reassess parameters of phenology in selected mosses on Signy I. to provide a first, explicit, test of predictions of changes in phenological parameters in herbarium specimens and natural accumulated, non-manipulated, field moss banks vs. the instrumental climate record. (2) reconstruct changes in phenology and carbon sequestration over longer periods (hundreds to thousands of years) through the use of growth patterns in preserved samples of two species retrieved from deep moss bank cores and compare these with the long term stable isotopic record (13C, 18O in plant cellulose) of past temperature, atmospheric CO2 concentrations and water availability. Together, these studies will enhance the accuracy with which we can link vegetation responses to past climate change (including past warm periods) and thereby better predict future climate impacts on plant communities. This NERC PhD studentship is linked with the BAS core science programmes "Climate and Chemistry" (CACHE), "Biodiversity, Function, Limits and Adaptation from Molecules to Ecosystems" (BIOFLAME) and Biological Sciences Long Term Monitoring (BSD-LTMS), with a focus on using biological and palaeobiological evidence to improve understanding of the interactions between climate and biological processes over past and present timescales, in order to better predict responses to future environmental variability and change. The PhD student will be based at the British Antarctic Survey but will spend time at the Department of Plant Sciences at the University of Cambridge, where stable isotopic studies will take place. Fieldwork is not currently planned during the studentship, but it is hoped there may be opportunities developed. The ideal student will have an excellent degree in Biological or Palaeobiological Sciences, very good analytical skills, and a strong interest in Earth system processes. For further details about the British Antarctic Survey please see: http://www.antarctica.ac.uk Applicants should include a cover letter, a CV and the e-mails of two referees. Closing date for applications: 16 March 2008 Applications and enquiries should be addressed to: Dr Dominic Hodgson |
