Mr Giles Ross


Graduated Master of Philosophy (2018)

Thesis Title

Impacts of elevated CO2 and ecosystem restoration on belowground biodiversity in Cumberland Plain Woodlands

Project description

Giles RossLand-use intensification and climate change are the two most pressing challenges caused by human actions to which ecosystems must adapt, in order to remain sustainable in the long-term. These two global change agents reduce the above and belowground biodiversity of terrestrial ecosystems, and influences critical ecosystem functioning essential for ecosystem stability. Assessing how biodiversity recovers following these impacts, can help shape strategies for managing ecosystems such as the endangered Cumberland Plain Woodlands (CPW). In this project I aim to quantify belowground biodiversity responses to elevated atmospheric carbon dioxide concentration using the Eucalyptus Free Air CO2 Enrichment (EucFACE) facility, and to further assess whether restoration of CPW increases belowground biodiversity and ecosystem functioning.

Belowground soil invertebrates and microarthropods play a key role in soil carbon (C) and nutrient cycling due to their role in leaf litter decomposition and organic matter dynamics through direct and indirect effects (i.e. as microbial grazers, predators, etc.). Oribatid mites will be used as indicators of belowground biodiversity responses to eCO2 and restoration because of their ubiquity, species diversity and sensitivity to soil disturbance through land-use. Using a combination of morphological sorting and molecular metabarcoding techniques, it is possible to acquire reliable measures of mite species compositions (presence/absence) and community abundances, by simultaneously sequencing the mitochondrial "barcode" COI region from multiple specimens. This will allow me to rapidly assess oribatid mite biodiversity and relate this to microbial community composition and ecological functioning. This project will help develop a protocol for metabarcoding analysis of soil faunal assemblages, which can then be applied more broadly.

Research Supervisors

Dr Uffe Nielsen and Professor James Cook