Destabilisation of terrestrial ecosystems in the high Arctic by extreme winter warming

The high Arctic is warming at an alarming rate, disrupting soil carbon, nutrient and hydrological cycles. This is resulting in increased soil microbial activity with subsequent increases in nutrient availability and hence plant productivity and nutrient losses to the wider environment. Losses of the greenhouse gases, nitrous oxide, methane and carbon dioxide result in a negative feedback, exacerbating future climate change, whilst increased losses of nitrogen and phosphorus could result in ecosystem eutrophication. Whilst much is already known about the effects of summer warming on ecosystem functioning in the high Arctic, little is known about the importance of winter warming on the carbon, nutrient and hydrological cycles of this fragile ecosystem. In recent years, this frozen winter period has been broken by prolonged periods where temperatures have risen well above temperatures above which microbial and plant activity restarts, and these unprecedented periods of winter defrosting are predicted to increase in frequency.

In this project, you will explore the effects of enhanced frequency of winter defrosting on carbon and nutrient cycling, focussing on the environmental consequences, such as the loss of soil organic matter and nutrient capital, increased greenhouse gas emissions, changes in plant performance and competition, and increased losses of nutrients. You will become competent in the use state-of-the-art methods to study the atmospheresoil-plant interactions, including portable greenhouse gas emission measurement equipment, stable and radioisotopes and metabolomics. The research will use a combination of laboratory and field-based experimentation, requiring regular visits to the high Arctic.

Eligibility

Applicant should hold a 2:1 degree or above in a subject related to this PhD project including: Biology, Environmental Science, Microbiology, Agriculture, Biotechnology.

Enquiries

For further information please contact Prof. Sacha Mooney (Sacha.Mooney@nottingham.ac.uk).