University of Cambridge
Cambridge CB2 3EA
- MRes Marine Biology, University of Plymouth
- BA Biological Sciences, University of Oxford
Mobilizing terrestrial primary production into aquatic food webs
Boreal lakes hold more than half of Earth’s freshwater. Understanding their functioning is highly important for predicting how anthropogenic pressures on land will affect freshwater ecosystems and the multiple services – clean drinking water, healthy fish populations, recreational areas – they provide us with. The vertical energy transfer that occurs in aquatic food webs has been shown to be highly complex, with organic carbon inputs from terrestrial ecosystems subsidizing large amounts of secondary production. Indeed, by providing a source of organic matter (OM) derived from vegetation and soil, terrestrial habitats can contribute between 30-70% of the organic carbon content of organisms in lakes. The mechanisms underlying initial energy transfer at the base of lake food webs remain poorly understood though.
The aim of my PhD is to understand how terrestrial resources are integrated into aquatic food webs by focusing on the biological composition of sediments and the way in which processing of OM by bacterial communities depends on interactions with algae. I will identify the dominant microbial groups in sediment samples, to see how these relate to mineralization rates and to their surrounding watersheds. I will then determine in the lab how the productivity of these communities is influenced by competition with algae for inorganic nutrients. I will also work within a larger whole-lake experiment (Ontario, Canada) consisting of artificial delta ecosystems and test how changing OM supplies influence energy transfer in the field. Finally, the influence of land use on phytoplankton abundance and nutrient availability will be tested using field observations on watershed characteristics and lake biochemical data.
Other Professional Activities
- Entente Cordiale Scholarship, British Council
- Mellon Bursary, Clare Hall, University of Cambridge
- Fondation de la Vocation Bursary