Dr Andrea Baker
Postdoctoral fellow, Earth Sciences Department, Stellenbosch University
Phone: +27 21 808 3814
I am an organic geochemist specialising in organic matter (OM) cycling in peatlands, which includes defining OM sources, humification and methanogenic processes under different redox conditions, and the environmental parameters that dictate rates of accumulation versus degradation of OM in peatlands. The focus of my PhD was to analyse biomarkers (alkanes, fatty acids, sterols and ketones) and compound specific carbon isotopes from leaf waxes using specifically configured GCMS instruments on peat samples from the ancient sub-tropical Mfabeni peatland, adjacent to Lake St Lucia, and reconstruct the regional palaeoenvironmental fluctuations over the last 50 thousand years.
Currently I am involved in a collaboration with colleagues at the Organic Chemistry department at Bristol University to set up a local HPLC method to analyse a quantitative temperature proxy specifically adapted for peatlands which employs branched glycerol dialkyl glycerol tetraethers (brGDGT) compounds. This method will be used to produce a regionally refined brGDGT calibration and tested using the Mfabeni archive to allow for more accurate temperature reconstructions from Southern African terrestrial archives.
I'm also involved in identifying water masses and changes in seasonal biomass production in the Southern Ocean as part of the South African National Antarctic program. Water samples, collected during the winter cruise 2017 on the S. A. Agulhas II along a 30⁰ E transect up to depths of 4250 m, were analysed on a Picarro L2140-i for δ18O, δ17O and δD and plotted against salinity and temperature readings to help identify water masses, ocean fronts and seasonal primary production zones.
Establish a brGDGT palaeotemperature HPLC analysis method at Stellenbosch University to produce a regionally refined brGDGT calibration so that quantitative and high-resolution temperature reconstructions can be produced from southern African terrestrial archives.
Set up and manage Picarro stable carbon (G2201-i), nitrogen (G5131-i) and oxygen (L2140-i) isotope analysers and their peripherals. Publish oxygen and deuterium isotope profile data sets from the Southern Ocean to identify water masses and constrain seasonal changes in ocean productivity.
Doctor of Philosophy (PhD) in Organic Geochemistry (Geology), Department of Earth Sciences, Stellenbosch University, March 2016.
Thesis title: Bulk geochemical, biomarker and compound specific isotope records of palaeoenvironmental controls on peat forming processes in Mfabeni peatlands, KwaZulu Natal, South Africa since the late Pleistocene.
- Baker, A., Routh, J., Blaauw, M., Roychoudhury, A.N., 2014. Geochemical records of palaeoenvironmental controls on peat forming processes in the Mfabeni peatland, KwaZulu Natal, South Africa since the Late Pleistocene. Palaeogeography. Palaeoclimatology. Palaeoecology. 395, 95–106.
- Baker, A., Routh, J., Roychoudhury, A.N., 2016. Biomarker records of palaeoenvironmental variations in subtropical southern Africa since the late Pleistocene: evidence from a coastal peatland. Palaeogeography. Palaeoclimatology. Palaeoecology. 451, 1-12.
- Baker, A., Pedentchouk, N., Routh, J., Roychoudhury, A.N., 2017. Climate variability in Mfabeni peatlands (South Africa) since the Late Pleistocene. Quaternary Science Reviews. 160, 57-66.
- Baker, A., Routh, J., & Roychoudhury, A. N., 2018. n-Alkan-2-one biomarkers as a proxy for palaeoclimate reconstruction in the Mfabeni fen, South Africa. Organic Geochemistry. 120, 75–85.
- IMOG 2013, Tenerife, 15 – 20 September 2013: Biomarker and n-alkane stable isotope records of climatic and environmental controls in the Mfabeni peatland (South Africa) since the Late Pleistocene.
- GSA 2014, Vancouver, 19-22 October 2014: Biomarker records of environmental changes and their climatic inferences in the Mfabeni peatland (South Africa) since the Late Pleistocene.
- AfQUA 2015, Cape Town 30 Jan – 7 Feb 2015: Leaf wax and bulk stable carbon isotope records of plant type assemblages and palaeoenvironment changes in Mfabeni peatland (South africa), since the Late Pleistocene.
- IMOG 2017, Florence, 17 – 22 September 2017: Climate variability in Mfabeni peatlands (South Africa) since the Late Pleistocene.
- Invited speaker, ICE AAPG 2018, Cape Town, 4 – 7 November 2018: Biomarker proxy records of palaeoenvironmental change in the Mfabani peatland, South Africa since the Late Pleistocene.