We once thought these icy settings were very barren environments, but we now know them to be viable habitats for microbial life. As such, they also serve as possible model habitats for life on other icy terrestrial planets, such as Mars and the moons of Jupiter. Many microbes in icy ecosystems are adapted to extreme conditions and play a role in regulating key biogeochemical cycles on Earth. Permafrost environments, for example, are significant producers of the greenhouse gas methane, known to be a significant contributor to global warming. Knowledge of the survival mechanisms utilised by such microbes and their role in biogeochemical cycles is therefore required in order to under-stand the evolution and persistence of life on Earth, and feedback between the climate and the Earth’s biosphere. The LOWTEX (LOW Temperature EXperimental) facilities will thus provide key analytical and experimental facilities that are required to improve our understanding of extreme icy environments.
Permafrost environments are significant producers of the greenhouse gas methane
One of the projects already underway includes the development and testing of miniaturised sensors to detect life in icy environments on Earth and Mars. Achieving a full understanding of biogeochemical processes in such places is currently limited by a lack of instruments that can be used for in situ, remote monitoring. Chemical and biosensors that can be used to infer life-mediated processes, or the characteristics of life itself, just do not exist for these extreme ecosystems. This programme unites the efforts of glaciologists, space scientists, oceanographers and biotechnologists derived from six UK universities and aims to develop sensing technologies for icy environments. The temperature-controlled facilities in LOWTEX will provide the testing site for such chemical and biosensors as they are developed. As Wadham said of the facilities: “One of the key ways to better understand the effect of climate on the polar regions is to recreate these icy environments close to home.”
Another project looks at whether the melting of glaciers might be accompanied by the release of methane trapped at the glacier bed, thereby amplifying the effects of global warming. Significant populations of micro-organisms have recently been found beneath such ice masses, but almost nothing is known about the carbon sources for these microbes (ie, what do they live on and where does their food come from?); the rates of microbial activity; and the full spectrum of products (gases) that they emit. This information is important for understanding the global carbon cycle on Earth. The fate of large amounts of organic carbon during the advance of the glaciers over the boreal forest during the last Ice Age, for example, is unknown and is likely to depend fundamentally on microbial processes in sub-ice environments. The possibility that this carbon is used by subglacial microbes and converted to carbon dioxide and methane has not previously been considered, but it may explain the variation in the Earth’s atmospheric greenhouse gas composition seen over the last two million years.
This last project represents an international effort, led from Bristol University, aimed at constraining details of the subglacial carbon cycle for the first time. It will also address the question of whether subglacial environments could be significant sources of greenhouse gases during periods of rapid ice wastage. Analytical and experimental investigations of microbial activity will be undertaken in LOWTEX and in specialist laboratories in the School of Chemistry and Department of Earth Sciences.
One way to understand the effect of climate on the polar regions is to recreate icy environments close to home
LOWTEX will become a unique national facility for cryospheric biogeochemical research. At its core is a series of seven temperature-controlled walk-in cold rooms for experimentation and sample storage, supported by a suite of interconnected wet/sediment laboratories for biological and non-biological sample preparation. LOWTEX also houses a research-grade analytical laboratory, with the latest instrumentation for the biogeochemical analysis of dilute solutions. The commissioning of LOWTEX reflects wider UK research council interest in the ‘hot’ scientific areas of climate change and life in extreme environments. To reflect this interest, LOWTEX has received almost £2 million in investment over the past 18 months from research councils, the University, and the EU.
The launch of the laboratories took place in Mongolian yurts on the only day of the year that Bristol had any snow. Frozen vodka shots were handed round to break the ice and chill-out tunes were provided by the Poles Apart string ensemble. Let’s hope that the research done at LOWTEX will help prevent such freezing conditions becoming a regular feature in Bristol.
Dr Jemma Wadham & Dr Jon Telling / School of Geographical Sciences