The Arctic plays host to a diverse range of microorganisms, including bacteria, algae, and viruses. The activity (or inactivity) or these microorganisms impacts the carbon and nutrient cycling among glaciers and soils, as well as the fertilization and productivity of Polar fjords and oceans, and the albedo of ice surfaces and thus the rate of sea-level rise. Microorganisms in cryospheric habitats must overcome a multitude of environmental stresses, including the freezing of water, desiccation, nutrient deficiencies, and exposure to UV irradiation. To counteract the potentially damaging effects of their harsh environment, they have evolved a range of adaptations. During extended periods of extremely harsh conditions (such as winter), dormancy is essential to enable life to persist. The PhD project seeks to measure the level of activity and dormancy of microorganisms from of a number of Arctic settings including glaciers and soils. This project will develop novel methods to determine the activity of microbial communities from Arctic habitats in situ and in the lab, and will involve laboratory and computational methods, with a possibility of Arctic fieldwork. The student will collaborate within a multi-disciplinary team across Queen Mary University of London and the Natural History Museum. The project would suit a student with an interest in environmental microbiology and biogeochemistry, and Arctic climate change. Opportunities for funding include London NERC DTP and QMUL Principal’s Postgraduate Research Studentships. For further information about the project, eligibility and future application deadlines in 2019/20, please contact Dr James Bradley.
The deep subsurface biosphere contains a vast proportion of Earth’s microbial life and organic carbon. In deep, energy-limited settings, microorganisms persist over extraordinarily long timescales with very slow metabolisms – constituting an important analogue to the potential for life beyond Earth. However, the subsurface is notoriously difficult to study because of its remoteness and limited access, as well as the low biomass concentrations and energy fluxes associated with microbial activity. Therefore, numerical models are pivotal in addressing how microorganisms endure, proliferate, and assemble in deep subsurface settings, and understanding the selective environmental pressures that determine energetic trade-offs between growth and maintenance activities. This PhD project provides the opportunity to work at the frontier of deep biosphere science by developing a microbially-explicit model for the subsurface. This model will provide quantitative insight into microbial and geochemical coupling in deep marine or terrestrial settings, and insight into the energetic limit of life. The project would suit a computational and numerate student with an interest in life in extreme environments, biogeochemistry, and microbial-biogeochemical modelling. Opportunities for funding include London NERC DTP and QMUL Principal’s Postgraduate Research Studentships. For further information about the project, eligibility and future application deadlines in 2019/20, please contact Dr James Bradley.