Dr Katie Hillyer1
1Queensland Government, Brisbane, Australia
Biography:
Katie is Acting Principal Scientist at the Aquatic Ecosystem Health team, Department of the Environment, Tourism, Science and Innovation, Queensland Government. She manages a long term estuarine water quality monitoring program that extends from Central to Far North Queensland. With a background in multi-omics, she is interested in the application of novel omics based tools, including eDNA, to the monitoring and management of complex aquatic systems, such as estuaries and coral reefs.
Abstract:
As local and global scale pressures on estuarine systems continue to grow, it is critical to develop indicators of system health. However, estuaries pose many logistical challenges to monitoring, being highly dynamic, turbid, and in many regions host to a range of deadly taxa.
Applying a metabarcoding approach, estuarine biota were characterised along a latitudinal gradient across three Queensland regions, estuarine zones, and water quality types. A total of 4757 detections, in 36 biota groupings were observed, the majority in seven: bacteria, plants, fungi, fish, ciliates, insects, and crustaceans.
Characteristic differences were observed in detected biota, structured primarily according to zone, and estuary, and to a lesser extent by region. However, at sites characterised by the poorest water quality, differentiation was observed; primarily in lower order groups, bacteria, cryptomonads, and ciliates, and photosynthetic groups, green algae, dinoflagellates, and diatoms. Lower diversity and total number of detections were observed overall at sites with impacted water quality, with a loss of zonation in the most human influenced region, at mid-estuary sites. However, this homogenisation was not observed for all biota groups, with higher aggregated counts and diversity observed for bacteria, plants, and archaea at the most impacted sites.
Many abiotic and biotic factors influence estuarine biota and their detection; this study serves as a snapshot for some of Queensland’s diverse, data poor systems subject to a range of impacts. A commitment to their ongoing monitoring is required to inform locally relevant indicators of system health, and facilitate their management for future resilience.