Raissa Gill
Project Title: Microbial dynamics of wildfire particulate matter deposition in temperate Australian estuaries
Supervisors: Professor Martina Doblin & Associate Professor Fraser Torpy
Contact Detail: Raissa.L.Gill@student.uts.edu.au
Project Background: Aerosols have been well studied in the context of human respiratory health, however understanding their impact on aquatic systems is a relatively new field of research. At present, biogeochemical cycles are known to be modified through atmospheric deposition of desert dust, which fertilises the ocean with iron, a key limiting nutrient. While this represents the largest source of iron by mass, it is relatively insoluble compared to other sources such as wildfire. Given the recent 2019-2020 bushfire season, where huge quantities of aerosols were produced with virtually nothing known about their impact on coastal waters, understanding its impact on microbes – the base of the aquatic food web - is now a significant national priority.
Project Aims: The specific research aims of this project are to (1) characterise particulate matter collected during the Australian 2019-20 bushfire season, focussing on properties relevant for aquatic nutrient enrichment and toxicity, 2) determine the acute microbial response of estuaries to wildfire particulate matter deposition over a spatial scale in NSW, Australia, and 3) assess how wildfire particulate matter deposition impacts the microbial dynamics of a healthy NSW estuary over time and at varying doses.