Thesis: Using novel molecular approaches to assess the effect of environmental stressors on seagrass productivity
Seagrass meadows are amongst the most productive ecosystems in the world and sequester high concentrations of carbon in sediments. However, seagrasses are under threat due to shifts of several environmental factors: poor water quality; the formation of toxic sulphides in anoxic sediments; extreme saline conditions, and; high temperatures. The molecular physiological changes of seagrasses to these abiotic parameters remain largely unknown. However, knowledge about molecular changes is critical in order to better understand the overall plant stress response mechanisms which can be applicable and of high value to seagrass management globally. I will address this knowledge gap by applying novel molecular biomarker techniques such as metabolomics and proteomics on seagrasses from a variety of locations in Western Australia, using a combined field and mesocosm design. A mesocosm (tank) experiment will assess the effects of both high temperature and low light on three seagrass species from Shark Bay: Amphibolis antarctica, Posidonia australis and Halodule uninervis. In addition, the effect of low light on the inorganic carbon uptake rates of A. antarctica will be determined using stable 13C isotopes visualized via nanoscale secondary ion mass spectrometry (NanoSIMS). In situ experiments will be used to assess both the metabolic and proteomic response of Halophila ovalis and Halodule uninervis along environmental gradients in Shark Bay and the Swan-Canning estuary, respectively.
Why my research is important
The application of ‘omics’ techniques in my PhD will allow the detection of in depth ‘hidden’ stress responses of seagrasses which will significantly contribute to the development of “early warning” indicators of seagrass health.