In Focus: Research providing knowledge to inform the future management of aquatic plants and algae in the Coorong South Lagoon

Plants play a critical role in aquatic ecosystems, providing habitat and food that support the diversity and abundance of invertebrates, fish and birds. This is the case for the Coorong, with the presence and location of aquatic plants (seagrasses) and algae affected by the environmental conditions of the water and sediment. The hypersaline and nutrient-enriched conditions, which have persisted in the South Lagoon of the Coorong over the past two decades have led to a change in dominant plant community composition, from submerged aquatic seagrasses to large areas of filamentous and free-living algae, in turn reducing the biodiversity and resilience of this important ecosystem.

In our August issue of Goyder Institute eNews, we published our first In Focus article on the Goyder Institute-led research being delivered as part of the $77.8 million Healthy Coorong, Healthy Basin (HCHB) Program. This initiative of the Australian and South Australian governments aims to support the long-term health of the Coorong by providing evidence-based solutions to both immediate threats and future conditions under a changing climate. The Goyder Institute for Water Research is the delivery partner for research components of HCHB, providing independent research to inform future management decisions for the region. The Coorong is an area of immense environmental, cultural and social value to South Australia and Australia.

In this issue, we explore the aquatic plants and algae communities in the South Lagoon of the Coorong and the environmental conditions causing changes to these communities that have knock on effects for the wider ecosystem health of the Coorong. This research is being led by Professor Michelle Waycott of the University of Adelaide, in partnership with research teams at Flinders University and the South Australian Research and Development Institute (SARDI).

Three species of submerged aquatic plants have historically existed under different conditions in the South Lagoon of the Coorong: Ruppia tuberosa, Ruppia megacarpa and Althenia cylindrocarpa. One of these species, R. megacarpa, prefers conditions of lower salinities; while R. tuberosa and A. cylindrocarpa are both highly resilient species able to tolerate hypersaline conditions such as those currently present in the South Lagoon of the Coorong. When not flowering, two of the seagrass species R. tuberosa and A. cylindrocarpa that currently co-exist in the South Lagoon are indistinguishable, in fact, it takes a world expert or DNA analysis to correctly identify the two species.

The research being undertaken by Prof. Waycott’s team is providing exciting new insights into the interactions between aquatic plants and algae, and how management efforts can help to restore the seagrass community and improve aquatic health in the South Lagoon and across the Coorong system.

“Submerged aquatic plants such as Ruppia and Althenia are what are known as ‘keystone’ species for the Coorong South Lagoon” said Prof. Waycott. “The plants contribute to maintaining water quality and stabilising sediment, while providing habitat for invertebrates and fish, and food for waterbirds.”

“However, the Coorong South Lagoon has seen changes in environmental conditions over the past 20 or so years where both salinity and the amount of nutrients has increased, and this has led to the reduction in aquatic plant populations and greater amounts of filamentous algae growing in the Coorong” said Prof. Waycott. “The algae can impede waterbird feeding, and adversely affect aquatic plants by restricting growth, reducing reproduction, and affecting the nutrient dynamics of the water and sediment.” “Consequently,” said Prof. Waycott, “the aquatic plant community is in a vulnerable state requiring restoration to help improve the environmental condition of the Coorong South Lagoon.”

The research team is undertaking intensive field work in the Coorong, sampling over 100 different locations in large-scale seasonal surveys to determine the presence and health of the aquatic plant communities and to gain further understanding of the impacts that the algae is having on these plants. The team is also monitoring specific sites across the southern Coorong (South Lagoon and southern North Lagoon) fortnightly to observe seagrass growth and automatic data loggers have been deployed to continuously monitor the environmental conditions being experienced throughout the life cycle of the seagrass community.

“The good news is that we have found more of the aquatic plant community at these 100 locations than expected” explained Prof. Waycott. “Unfortunately, the condition of these plants is often poor and the growth of the algae, which starts in late spring and continues over summer, really inhibits plant growth and reproduction. The filamentous algae, a symptom of the excess nutrients, is hampering the long-term recovery of the aquatic plant community following large-scale losses from the Coorong during the 2001-2010 period of the Millennium Drought.”

The submerged aquatic plant communities also play a key role in the nutrient dynamics of the Coorong ecosystem. As highlighted in last month’s In Focus article, much of the sediment in the South Lagoon of the Coorong contains little or no oxygen. When Ruppia plants gather enough light and photosynthesise, their roots release oxygen into the sediment. This oxygen release supports nutrient cycling and enhances sediment health by reducing the amount of oxygen-deprived (anoxic) sediment. Therefore, further increasing the presence of aquatic plant communities throughout the South Lagoon, while reducing the impact of the algae on these communities, can help to improve the nutrient conditions and nutrient cycling within the Coorong.

“We are working closely with Assoc. Prof Luke Mosley and his Nutrient Dynamics team of the HCHB Program to further understand how improving the presence and condition of the aquatic plants throughout the Coorong South Lagoon can help improve the nutrient conditions of the region” said Prof. Waycott. “In addition, we are examining the responses of the seagrass community to changes in water quality and sediment types to help identify thresholds for plant survival and subsequently future habitat requirements for the plants. This will provide a better understanding of the factors which are driving algal growth in the Coorong and how it affects the aquatic plant community.”

The next year of research being undertaken by the Goyder Institute team will further investigate the suitability of habitat throughout the Coorong South Lagoon for the growth of aquatic plants; as well as understanding the associations between aquatic plants, environmental conditions and microorganisms; and assessing the success of previous aquatic plant restoration efforts within the Coorong South Lagoon. The data collected as part of the aquatic plants and algae component of the HCHB Program will also be incorporated into complex biogeochemical modelling, which will give a greater understanding of the Coorong ecosystem as a whole and, allow predictions of the impacts of environmental change or effectiveness of interventions in improving ecosystem health.

More information on the HCHB aquatic plants and algae research can be found here. For further information on the Goyder Institute-led HCHB research, please contact Dr Alec Rolston.

This project is part of the Department for Environment and Water’s Healthy Coorong Healthy Basin Program, which is jointly funded by the Australian and South Australian governments.

Tags: Coorong Lower Lakes & Murray Mouth SA Department for Environment and Water (DEW) Flinders University Goyder Institute News Murray River Murray-Darling Basin South Australian Research and Development Institute (SARDI) University of Adelaide Water for the Environment Wetlands

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We are delighted to welcome Fiona Adamson and Dr Hamideh Nouri to the Goyder Institute for Water Research team.  Fiona has joined us on secondment from Institute partner Flinders University, where she has been providing administrative and
The Millennium Drought (1996-2010) had a devastating environmental, economic, social and cultural impact throughout the Murray-Darling Basin. The Coorong, Lower Lakes and Murray Mouth (CLLMM) region, situated at the end of the Basin, was no exception.

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Chris Wright

Manager Water Science, DEW

Chris Wright holds significant experience in public sector senior leadership, having led policy, scientific and operational business units over the last twelve years in both State and Commonwealth government agencies. Chris has excellent experiences in leading policy and strategy formulation. He is skilled in building and maintaining networks across the public and private sectors to facilitate business delivery; leading and negotiating with others to achieve outcomes; and in bridging the science-policy gap, drawing on earlier roles in geospatial information systems (GIS) consulting. Chris’s formal qualifications include a Bachelor of Social Science, a Masters of Spatial Information Science and graduation from the AICD Company Directors course in 2019.

Dr Ilka Wallis

Senior Lecturer, Flinders University

Dr Ilka Wallis is a hydrogeologist with areas of expertise in quantitative hydrogeology and geochemistry. Ilka focuses on the development of reactive geochemical transport models which integrate fundamental processes that are normally studied in isolation (hydrogeological, mineralogical, geochemical and biochemical).

Ilka is also an Adjunct Professor, Department of Civil Engineering, University of Manitoba, Canada since 2017.

Peter Goonan

Environmental Science Branch, EPA

Peter Goonan is the Principal Aquatic Biologist in the Environmental Science Branch of the EPA. He has over 30 years’ experience monitoring the condition of aquatic ecosystems in SA and assessing the environmental effects caused by discharges, deposits and contaminants entering inland and coastal waters. He specialises in aquatic invertebrate identification and their responses to contaminants and water quality stressors. He also provides expert professional advice relating to water quality risks, regulation, policy, and strategic directions, and represents the EPA as an expert witness in court.

Dr Paul Monis

Manager, Research Stakeholders and Planning, SA Water

Dr Paul Monis is a technical expert within SA Water’s Business Services group, which provides scientific expertise to support the delivery of water and wastewater services to SA Water’s customers. He has specialist expertise in the areas of biotechnology and microbiology, with almost 20 years’ experience applying DNA-based and other technologies to address water quality challenges posed by microorganisms, especially enteric pathogens. Dr Monis also holds title of Adjunct Associate Professor at Flinders University, the University of Adelaide and UniSA.

Jennie Fluin

Principal Advisor Research Partnerships, DEW

Jennie’s role in the Department for Environment and Water (DEW) allows her to foster and strengthen opportunities for researchers to better connect with government to enable evidence-based decision making. Jennie has extensive experience working in both universities and government, allowing her to bridge the divide between the two sectors. She is focused on connecting natural resource researchers with natural resource decision makers, and facilitating fit for purpose partnerships.

Dr Tanya Doody

Principal Research Scientist, CSIRO

Dr Tanya Doody is a Principal Research Scientist working on high impact spatial eco-hydrological projects within CSIRO’s Land and Water Business Unit. Dr Doody leads the Managing Water Ecosystems Group, based in Adelaide, Albury and Canberra and has significant experience in quantifying the water requirements of vegetation and at times, their impact on water resources. This involves ecophysiological field-based research to underpin remote sensing tools to scale regionally to improve our understanding of the effect of flood regimes on the health of water-dependent ecosystems on the Murray-Darling Basin floodplains. Additional research includes investigating the ecological response of vegetation to water availability and environmental water to inform integrated basin water planning and management.

Professor Lin Crase

Dean of Programs (Accounting & Finance), UniSA

Professor Lin Crase is Professor of Economics and Dean of Programs (Accounting & Finance) at UniSA. He joined UniSA in February 2016 as Head of School of Commerce. Prior to commencing at UniSA, Lin was Professor and Director of the Centre for Water Policy and Management at La Trobe University.

Lin’s research has focused on applied economics in the context of water. He has analysed water markets and the property rights that attend them, water pricing and numerous applications of water policy. Whilst his expertise includes the Murray-Darling Basin in Australia, he has also worked on projects in south Asia, Japan and Europe. Lin has published over 100 journal articles, numerous book chapters, four books and a range of other papers and opinion pieces.

Professor Justin Brookes

Director, Water Research Centre, University of Adelaide

Justin has broad research interests in limnology and water treatment with a primary focus on coupling between hydrodynamics, biology and water quality contaminants such as cyanobacteria and pathogens. He is a founding member of the management committee of the IWA Specialist Group on Lake and Reservoir Management and member of the Steering Committee for the Global Lakes Ecological Observatory Network.

Justin has a PhD and a Bachelor of Science degree with Honours from the University of Adelaide.

Daniel Flaherty


Daniel Flaherty is the Accountant for the Goyder Institute for Water Research.

Daniel has extensive experience in higher education having worked in senior financial management roles at the University of South Australia, Flinders University and the University of Adelaide over the past 26 years. Daniel has also been a Board Director on a number of university related entities. Prior to that, Daniel has worked in a range of agencies in the Commonwealth and State Governments.

Daniel is a Fellow of CPA Australia and has a Bachelor of Economics from the University of Adelaide.

Dr Alec Rolston

Interim Director

Alec Rolston joined the Institute in 2021 as Research Program Manager of the Goyder Institute’s research projects in the Healthy Coorong, Healthy Basin program. He has extensive experience in integrated water resource management, integrated catchment management, drinking water source protection and wetland ecology, conservation and management across Europe and Australia.

Alec holds a PhD from the National University of Ireland Maynooth and has worked with An Fóram Uisce|The Water Forum and the Dundalk Institute of Technology in Ireland as well as the MANTEL Innovative Training Network across Europe.

Alec spent his early career in Adelaide working with Flinders University through the Coorong, Lower Lakes and Murray Mouth (CLLAMM) Ecology Research Cluster and within the Department for Environment and Water.

Daniel Pierce

Research and Development Officer

Daniel Pierce has managed research projects at the Goyder Institute for Water Research since November 2017 under both the second and third terms of the Institute.

Daniel brings experience in project management and knowledge transfer and application from 4 years working as a Senior Hydrogeologist in the Department for Environment and Water (DEW) in South Australia and from 13 years of private sector work in environmental management, science and engineering in Australia and the South Pacific. His work with DEW has included providing technical advice to the development and revision of Water Allocation Plans around South Australia in collaboration with researchers and policy makers, and managing a team of groundwater modellers and hydrogeologists involved in an assortment of water resource management issues.

Daniel has a Bachelor of Engineering (Hons, Environmental) and a Bachelor of Science (Geography) from the University of Western Australia.

Professor Enzo Lombi

Dean of Research, UniSA STEM

Professor Lombi’s main contributions to environmental research cover various aspects of contaminant risk assessment, biogeochemistry, ecotoxicology and waste management. Furthermore, the methodological development he has pursued in his research has provided the basis for collaborative efforts in a variety of research areas ranging from soil fertility and plant physiology to human health issues related to contaminant uptake via occupational exposure and diet. In the last few years he has been increasingly focusing on the transformation and toxicity of manufactured nanomaterials in the environment.

Dr Carmel Pollino

Research Director Land and Water, CSIRO

Dr Carmel Pollino is a Research Director for Land and Water at CSIRO. She has 20 years of experience working on water issues in Australia and throughout Asia. Carmel has degrees in science and environmental law and works across the science and policy interface. Significant areas of research in Environmental Flows, Hydrology, Ecology and Integrated River Basin Planning. Carmel is the lead and also a contributor to global working groups on water and has published widely in this domain.

Professor Bronwyn Gillanders

Head of School of Biological Sciences, The University of Adelaide

Professor Bronwyn Gillanders is interim Head of School of Biological Sciences at the University of Adelaide. Prof Gillanders completed her BSc at the University of Canterbury, MSc at the University of Otago and her PhD at the University of Sydney. She has a research background in environmental science focused predominantly on freshwater and marine ecology.

Her research interests include integrated marine management; coastal carbon opportunities; multiple use activities and cumulative impact assessment; biology, ecology and fisheries of cephalopods; stocking and provenance of fish; plastics in the marine environment including in seafood; use of fish bones (and other calcified structures) for assessing ecological and environmental change. She has trained and mentored ~70 Honours and Higher Degree Research students and shaped the future of 1000s of students through her undergraduate teaching. She is passionate about encouraging capable women to enter and remain in science careers.

Dan Jordan

Director, Water Security, Policy and Planning, Department for Environment and Water (DEW)

Dan Jordan is the Director, Water Security, Policy and Planning, Department for Environment and Water (DEW). Dan is also the Basin Officials Committee Alternate Member for South Australia.

Professor Okke Batelaan

Dean, School of the Environment, Flinders University

Professor Okke Batelaan is a graduate of the Free University of Amsterdam, Netherlands (MSc – Hydrogeology) and of the Free University Brussels, Belgium (PhD – Engineering). He worked for more than 20 years at the Free University Brussels and also led the hydrogeology group at the KU Leuven, Belgium since 2006. He was chairman of the Interuniversity Programme in Water Resources Engineering.

Since 2012 Okke Batelaan is Strategic Professor in Hydrogeology and currently Dean of the School of the Environment, Flinders University. Okke has broad experience in teaching groundwater hydrology, groundwater modelling, GIS and remote sensing for hydrological applications. He was supervisor of more than 140 MSc and 25 PhD students. He has extensive research experience and a publication record in shallow groundwater hydrology and modeling, recharge-discharge estimation and modeling, urban hydrology and distributed modelling, ecohydrology and impacts of land use and climate change on groundwater systems. He coordinated and participated in a large number of projects in Europe, Africa, South America, Asia and Australia. He is editor-in-chief of Journal of Hydrology: Regional Studies and of MDPI-Hydrology.