Sharing resources to promote diversity: do co-existing plants use different forms of phosphorus to reduce competition for nutrients?

Supervisors: Dr Gareth K Phoenix and Dr Duncan D Cameron

Key words: phosphorus, competition, plant nutrient acquisition, resource partitioning, ecology, ecophysiology

Competition for resources is a major mechanism that controls the biodiversity of communities. Where co-existing organisms share a resource by using different forms of that resource (“resource partitioning”), competition is reduced and hence co-existence of those organisms is promoted. In many plant communities worldwide, phosphorus (P) is the most important nutrient for plant growth, and excitingly our recent work suggests that different plant species may in fact prefer different forms of phosphorus in soil. Given the universal importance of P as an essential nutrient for plant growth, this sharing of P by using different forms may be a globally important mechanism regulating ecosystem biodiversity. Despite our early evidence however, the strength of this as a driver of community structure, how broadly it operates over space and time, and against other environmental drivers such as ecosystem nutrient enrichment (e.g. from pollution) remains unknown. This PhD will therefore investigate resource partitioning of P and explore how, and how strongly, preference for different P compounds among co-existing plant species operates. It will use a combination of laboratory, growth chamber and field studies. Field work will focus on floristically rich grassland communities in the Peak District National Park with further opportunity to expand the study into Arctic tundra.

The project would suit a highly motivated, independently thinking student with a background in/enthusiasm for plant ecology/biology, nutrient acquisition by plants and the mechanisms that regulate plant community diversity. The project will include use of radio-isotope P compounds – full training will be given.

For more information about how to apply, or the application process, please contact Mrs S Carter (s.a.carter@sheffield.ac.uk).

To apply now go to: http://www.sheffield.ac.uk/postgraduate/online