Impacts of CO2 and O3 on sugarcane physiology and productivity. Geography NERC GW4+ DTP PhD studentship

This project is one of a number that are in competition for funding from the NERC Great Western Four+ Doctoral Training Partnership (GW4+ DTP). The GW4+ DTP consists of the Great Western Four alliance of the University of Bath, University of Bristol, Cardiff University and the University of Exeter plus six Research Organisation partners: British Antarctic Survey, British Geological Survey, Centre for Ecology and Hydrology, the Met Office, the Natural History Museum and Plymouth Marine Laboratory. The partnership aims to provide a broad training in earth and environmental sciences, designed to train tomorrow’s leaders in earth and environmental science.

For further details about the programme please see http://nercgw4plus.ac.uk/

Supervisors:

Main Supervisor: Prof Stephen Sitch (University of Exeter)
Co-Supervisor: Dr Lina Mercado (University of Exeter)
Co-Supervisor: Dr Alex Cheesman (James Cook University)
Co-Supervisor: Dr Lucas Cernusak (JCU)
Co-Supervisor: Felicity Hayes (CEH, Bangor)

Project description:

Carbon dioxide (CO2) and tropospheric ozone (O3) have physiological impacts on agricultural crop productivity. Tropospheric ozone is the third most important anthropogenic greenhouse gas and is a global air pollutant responsible for an estimated $14-$26 billion loss in crop yield each year. O3 enters leaves, causing oxidative stress which decreases photosynthesis, plant growth, biomass accumulation. Tropical vegetation was highlighted in Sitch et al. (2007) as potentially most vulnerable to future O3 scenarios given their high productivity, high stomatal conductance and environmental conditions conducive to O3 uptake. Sugarcane is an important tropical crop in the production of raw sugar and has feedstock for ethanol (biofuel) production. Globally 1,88 million metric tons of raw sugar are produced annually, with the global sugar market worth ~ $100 billion/year. However, little is known about how changing air quality in the tropics impacts sugarcane.

Project aims and methods:

This project will provide the first comprehensive set of measurements of the individual and combined effects of O3 and CO2 on the plant physiology, biomass accumulation and yield in sugarcane.

Experiments for this project will be conducted at the controlled environment greenhouses, housed at the James Cook University (JCU) in Cairns, Australia. Sugarcane plants will be exposed to CO2, O3 doses in isolation and in combination, from which a set of physiological measurements will be collected to elucidate individual and combined effects. Finally, based on the obtained empirical understanding, a conceptual model of the key processes affecting sugarcane physiology and productivity will be devised. This conceptual model for sugarcane, can be later used to inform the JULES-CROP model, as part of the UK Earth System model.

The project leverages access to experiments from an ongoing NERC funded project on investigating impacts of O3 on tropical tree and crop physiology and productivity at the controlled environment greenhouses, housed at JCU in Cairns, Australia (University of Exeter with partners at JCU).