Lead supervisor: Adam Pellegrini, Plant Sciences
Co-supervisor: David Coomes, Plant Sciences
Brief summary:
The project will leverage fieldwork and lab analyses of ecosystem carbon in a range of grasslands spanning Africa, South America, and North America, to estimate the conditions under which grasslands may serve as net-carbon sinks.
Importance of the area of research concerned:
As the global community develops pathways to achieve net-zero greenhouse gas emissions, there is a pressing need to refine estimates of carbon fluxes in natural ecosystems. Grasslands, which span an area five-times the size of the Amazon, offer a large opportunity to sequester carbon but interface with agricultural development. Thus, changing the management to sequester carbon needs to be carefully balanced with other stakeholder motivations such as production of cattle. Given rangelands support both subsistence agriculture in developing countries and national economies in developed countries, they are globally relevant.
Project summary :
Grasslands, which span ~15 million km2, play a key role in the global carbon cycle but much of this area has become either cultivated cropland or under active human management as rangelands. Thus, managing grasslands can potentially sequester large amounts of carbon, but both understanding the potential sequestration, its stability in the soils, and what sort of incentive schemes are successful (e.g., carbon credits), are unconstrainted. This project is part of a five-year grant that aims to produce a step-change in how carbon in grasslands is measured and modelled. The project will work to constrain estimates of how grassland management may lead to the sequestration or losses of carbon. It will be done by considering economic tradeoffs, suitability under climate change pathways, and other disturbance regimes such as fires.
What will the student do?:
The PhD will involve sampling ~15 fire-frequency and grazing manipulation experiments across the globe. Alongside a postdoctoral researcher, the student will measure plant biomass and productivity in the field, take soil samples and conduct analyses in the field, and contribute to a larger lab group initiative in compiling datasets for ecological synthesis.
This research project will both conduct fieldwork and lab analyses to measure soil organic carbon in a range of grasslands spanning Africa, South America, and North America, as well as conduct a detailed analysis of existing data. The project will be in collaboration with a postdoctoral researcher in the Pellegrini group. It would be expected that the student spends several months in the field (not necessarily continuously) each year for two years.
References - references should provide further reading about the project:
Bai, Yongfei, and M. Francesca Cotrufo. "Grassland soil carbon sequestration: Current understanding, challenges, and solutions." Science 377.6606 (2022): 603-608.
https://www.science.org/doi/abs/10.1126/science.abo2380
Scurlock, J. M. O., and D. O. Hall. "The global carbon sink: a grassland perspective." Global Change Biology 4.2 (1998): 229-233.
https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1365-2486.1998.00151.x
Applying
You can find out about applying for this project on the Department of Plant Sciences page.