PhD studentship Supervised by Dr Tom Shepherd [1], The James Hutton Institute, Dr Scott Johnson [2], University of Western Sydney, Dr Adam Vanbergen [3] and Professor Rosie Hails [4] at CEH and Dr Hefin Jones [5] at Cardiff University
Trophic cascades in a changing climate – Effects of elevated CO2 on the breakdown of plant defences.
Carbon dioxide emissions from anthropogenic sources have increased in the atmosphere since the industrial revolution. Atmospheric CO2 concentrations are predicted to rise from the current 350ppm to 550ppm by 2050.
Initial evidence suggests plants will benefit from the fertilising effect of elevated levels of CO2 (eCO2), with plant productivity in C3 plants predicted to increase by 10-20%. However, recent evidence suggests increases in productivity may be counteracted by CO2-induced changes to plant defences against herbivory.
It is currently unknown how changes to plant defences will cascade to higher trophic levels within a community. How will eCO2-induced changes to plant defences affect herbivore performance? How will these alterations affect interactions with higher trophic levels? Will predatory species abundance increase in response to increased prey availability, suppressing any change to herbivore populations, or will eCO2-induced reduction of plant defences prevent this?
My PhD will aim to provide answers to these questions by using the red raspberry, Rubus ideaus and the large raspberry aphid Amphorophora idaei as a model plant-herbivore system. I will investigate the effect of eCO2 on higher trophic levels by using a specialist predator, a parasitoid wasp, Aphidius ervi, and a generalist predator, the harlequin ladybird, Harmonia axyridis.
I completed a BSc in Zoology at Sheffield University and an MSc in Biodiversity and Conservation at Leeds University. Before starting my MSc I worked for 18 months as a research assistant for Dr Andrew Beckerman at Sheffield University. Here I investigated the indirect effects of predation on the life history, morphology and behavioural characteristics of Daphnia pulex.
Links:
[1] https://www.hutton.ac.uk/staff/tom-shepherd
[2] http://www.uws.edu.au/hie/people/researchers/doctor_scott_johnson
[3] http://www.ceh.ac.uk/StaffWebPages/DrAdamVanbergen.html
[4] http://www.ceh.ac.uk/staffwebpages/ProfessorRosemaryHails.html
[5] http://www.cardiff.ac.uk/biosi/contactsandpeople/stafflist/i-l/jones-hefin-dr-overview_new.html