Bio-protection: long-term modification of rock weathering by microorganisms?

(BASU_RH20ARIES)

Bio-protection: long-term modification of rock weathering by microorganisms?

(BASU_RH20ARIES)

Project Description

Supervisors

Dr Anirban Basu, Department of Earth Sciences, Royal Holloway University of London (RHUL)

Dr Javier Cuadros, Department of Earth Sciences, Natural History Museum (NHM)

Dr Anne Jungblut, Department of Life Sciences, Natural History Museum

 

Scientific background

One of the most important questions related to the critical zone research and long-term climate stability is how biology influences weathering. This PhD project investigates a crucial question of Earth’s biogeochemistry: do microorganisms accelerate rock weathering or slow it down under environmentally relevant conditions? Because microorganisms have been extracting nutrients and energy from rocks for ~3.7 billion years there is a mutual life-lithosphere modification, which is not yet well-explored. Very slow weathering observed at the field scale contradicts the idea of microbially enhanced rapid weathering from experimental studies. Therefore, it is important to test the hypothesis that microbial biofilms around minerals inhibit weathering by regulating the transport and loss of weathering products. Knowing the metabolic diversity of microbial communities, grain-scale interactions between microbial communities and minerals, and the weathering intensity is important to link the roles of biological agents to erosion and climatic change.

Research methodology

Gran Canaria (Canary Islands) is a natural laboratory providing two essential constraints for the project – 1) volcanic rocks of homogeneous composition and the same age, and 2) large differences of rainfall inducing large differences of microbial development in soils. This PhD project will apply cutting-edge chemical, mineralogical, isotopic and microbiology techniques and bioinformatics to determine the relationship between soil weathering rates, atmospheric precipitation and microbial communities and assess how microorganisms modify weathering intensities. U series isotopic disequilibrium (234U/238U) in porewater/stream water and soils will be used to independently constrain the weathering intensity.

Training

The student will obtain training in field work and sample collection in Gran Canaria. They will receive training in X-ray diffraction, wet chemical analysis methods, molecular, microbiology techniques and bioinformatics (environmental DNA, high throughput sequencing, microbial community structure analysis, metagenomics and phylogenetic interference) at NHM. They will also receive training in clean lab techniques and isotopic measurements using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) at RHUL. They will gain highly interdisciplinary quantitative geochemical skills integrating mineralogical, microbial, chemical and isotopic data.

Person specification

A good background in Earth Sciences, preferably with some knowledge of chemistry and biology.

References

  • S. L. Brantley and 26 more authors (2011) Twelve testable hypotheses on the geobiology of weathering. Geobiology 9, 140-165. DOI: 10.1111/j.1472-4669.2010.00264.x
  • Javier Cuadros, Mara Cesarano, William Dubbin, Stuart W. Smith, Alexandra Davey, Baruch Spiro, Rodney G.O. Burton, Anne D. Jungblut (2018) Slow weathering in a sandstone-derived Podzol (Falkland Islands) resulting in high content of a non-crystalline silicate. American Mineralogist 103, 109-124. DOI: http://dx.doi.org/10.2138/am-2018-6230
  • Mitchell, R.L., Cuadros, J., Duckett, J.G., Edgecombe, G.D., Mavris, C., Pressel, S., Sykes, D., Kenrick, P. (2016) Mineral weathering and soil development in the earliest land-plant ecosystems Geology 44, 1007-1010. DOI: 10.1130/G38449.1
  • Anirban Basu, Shaun T. Brown, John N. Christensen, Donald J. DePaolo, Paul W. Reimus, Jeffrey M. Heikoop, Giday Woldegabriel, Ardyth M. Simmons, Brian M. House, Matt Hartmann, and Kate Maher (2015). Isotopic and Geochemical Tracers for U(VI) Reduction and U Mobility at an in Situ Recovery U Mine. Environmental Science & Technology 2015 49 (10), 5939-5947 DOI: 10.1021/acs.est.5b00701
  • Li L., and 12 more authors (2018). Weathering dynamics reflected by the response of riverine uranium isotope disequilibrium to changes in denudation rate. Earth and Planetary Science Letters. 500, 136-144. https://doi.org/10.1016/j.epsl.2018.08.008

Key Information

  • This project has been shortlisted for funding by the ARIES NERC Doctoral Training Partnership, and will involve attendance at mandatory training events throughout the course of the PhD.
  • Successful candidates who meet UKRI’s eligibility criteria will be awarded a NERC studentship - UK and EU nationals who have been resident in the UK for 3 years are eligible for a full award.
  • Excellent applicants from quantitative disciplines with limited experience in environmental sciences may be considered for an additional 3-month stipend to take advanced-level courses in the subject area (see https://www.aries-dtp.ac.uk/supervisors/additional-funding/).
  • This studentship will start on 1st October 2020, and the closing date for applications is 12:00 on 7th January 2020.
  • Shortlisted applicants will be interviewed on 18/19 February 2020.
  • For further information, please contact the supervisor.
  • Please note that the joint NERC-ESRC ARIES-SeNSS studentship projects have different deadlines and funding arrangements. For full details please visit https://senss-dtp.ac.uk/aries-senss-joint-studentship, or contact SeNSS.dtp@uea.ac.uk.

Studentship Open for Applications

Apply Now