Marine host-microbiome interactions under environmental change

The University of Sydney

In my postdoctoral research, I explore how marine host–microbiome interactions respond to environmental change. My work focuses on seagrasses and seaweeds, using experimental field manipulations and global meta-analyses to uncover how environmental stressors shape their microbial communities — and how these microbes, in turn, affect host health and performance.

I aim to understand where seagrasses get their microbes from and how both local conditions and host genetics shape these communities. I am also testing methods to manipulate microbes across seagrass species to test their effects on plant performance and resilience to stress. Together, these approaches guide efforts to restore and protect coastal ecosystems under climate change.

PhD project: The role of belowground microbes in seagrass responses to environmental stress.

Supervised by Ezequiel Marzinelli (The University of Sydney) and Paul Gribben (UNSW)

Climate change is dramatically altering the environmental conditions that organisms are exposed to. Understanding the factors that contribute to the tolerance and resilience of organisms to environmental stressors is crucial for predicting and mitigating the impacts of environmental change. Belowground microbial communities play a critical role in plant health and performance, yet their influence on the performance of marine plants under environmental stress remains poorly understood. In this thesis, I investigated the role of rhizosphere and bulk sediment microbial communities in the performance of the dominant seagrass Zostera muelleri under key global stressors, including elevated ocean temperatures and nutrient variability. A review of existing literature revealed significant gaps in our understanding of the role of belowground processes on seagrass performance. In particular, the influence of belowground microbes on seagrass health and performance remains poorly understood, compared to terrestrial plants, limiting their potential application in management and restoration strategies.

Through experimental manipulations of rhizosphere and bulk sediment microbial communities, in aquarium and field experiments experiment, I aimed to understand these belowground processes in marine ecosystems. Understanding these processes might be the missing piece needed to enhance seagrass restoration and may result in a step-change in seagrass restoration success.