- Opportunity to work on highly novel proxies. Blues skies science, the thesis and paper outputs will have high impact.
- Fieldwork to collect fresh soil/lake surface samples from transects abroad (e.g. the USA, Europe, Japan).
- Collaboration and research visit to work with Prof. Xie at the China University of Geosciences, Wuhan and partners at CEH.
A wide range of environmental information from both terrestrial and marine realms is required from palaeoclimate archives to better understand the climate system and to provide a palaeoclimatic context for predictions of future rates of climate change, impact and Earth system sensitivity. Overall, far less attention has been paid to terrestrial environments, compared to the marine realm, due to the paucity of ubiquitous biomarkers with quantitative palaeoclimatic utility.
We have recently found strong correlations between 3-hydroxy fatty acid (3-OH-FA) distributions, synthesised within Gram-negative bacterial membranes, and environmental parameters (Wang et al., 2016). Based on this discovery we have defined new geochemical proxies for reconstructing temperature, pH and precipitation.
The ubiquitous natural distribution of Gram-negative bacteria means that these new techniques for reconstructing past climate have huge potential.
We have recently submitted the first manuscript to demonstrate that 3-OH-FA biomarkers can successfully reconstruct temperature and precipitation signals from an individual stalagmite (Wang et al, submitted).
This PhD project will undertake the next exciting steps in the development of these biomarkers:
- The production of new global scale calibrations to expand and refine the new proxies for pH and temperature and ensure wide uptake by the palaeoclimate community.
- First applications of new proxies to a variety of palaeoclimate archives beyond speleothems (lake sediments, ocean drilling sediment cores) on a variety of time-scales (Holocene to Cenozoic).
Geological work: Compile a collection of over 200 soil and sediment samples which span global gradients in temperature, hydrology and a diversity of bacterial and plant communities. Fresh samples will be obtained on field expeditions from regional transects (in Europe, the USA and Japan). In addition we have already obtained samples from the ISRIC soil repository and co-supervisor Griffiths possesses a frozen archive of soils from across the UK collected as part of nationwide soil surveys, and a recent NERC funded project (U-GRASS) under the Soil Security Programme.
Experimental work: All samples will be subjected to organic geochemical extraction and clean-up and analytical methods: i.e. acid hydrolysis and digestion Wang et al., 2012), extraction with organic solvents, separation into chemical fractions and analysis by GC-FID, GC-MS.
Training and Skills
CENTA students are required to complete 45 days training throughout their PhD including a 10 day placement. In the first year, students will be trained as a single cohort on environmental science, research methods and core skills. Throughout the PhD, training will progress from core skills sets to master classes specific to the student's projects and themes.
This project will also provide detailed training in the geochemical methods necessary for 3-OH-FA analyses for environmental reconstructions, including organic geochemistry provided at the Birmingham and a visit to world leading China University of Geosciences in Wuhan. The DR will also receive training in the collection and interpretation of transect data with colleagues at CEH.
This project will inevitably offer extensive networking opportunities with national and international scientists in addition to data handling and interpretation and scientific communication through writing, poster and oral presentations to academic and non-academic audiences.
Year 1: Obtain training in sample processing of soil and sediment sample material, organic geochemical techniques. First field season in USA. Generate data surface sediment samples and derive new calibrations.
Year 2: Second field season in Europe. Visit Prof. Xie, Wuhan. Present results at a domestic (BOGS) or smaller international meeting (Gordon conference) and prepare manuscript. Prepare samples from palaeoclimate archives.
Year 3&4: Possible Third field season in Japan. Finish remaining analytical work, present results at an international conference. Write up results for final thesis and additional papers.
Partners and collaboration (including CASE)
Close collaboration between CENTA partners (UoB and CEH) is integral to this project. This project also benefits from external collaborations with scientists working on 3-OH-FAs. We are seeking to make the project CASE with Isoprime UK (who are current CASE partners with Bendle). The PhD student will have excellent opportunities to engage in field-work and collaborate internationally. A research visit to work with Prof. Xie and Dr Wang at the China University of Geosciences (China UoG), Wuhan is of paramount importance. The collaboration between Dr Bendle and Prof. Xie’s group is leading the world in the exciting development of 3-OH-FAs as paleoclimate proxies.
Contact: Dr James Bendle.
Telephone: +44 (0) 121 41 46156