Innovative research assesses connectivity across the Murray–Darling Basin

Filling knowledge gaps about ecosystem functions within the Murray–Darling Basin is fundamental to sustainable water management moving forward, and one award-winning project has made strides in developing an innovative new approach to understanding connectivity across the Basin.

Sponsored by Water Research Australia (WaterRA), the AWA R&D Excellence Award was presented to CSIRO and the Murray–Darling Basin Authority (MDBA) at Ozwater’24 for the collaborative Ecosystem Functions project.
 
Aiming to fill knowledge gaps around hydrological connectivity, biological connectivity, habitat provision and productivity across the Basin, the project represents a world-first attempt to assess ecosystem functions at such a large scale.
 
The Australian Water Awards stand to recognise innovation and excellence within the water community, with state and territory project awards now open for nominations.
 
MDBA Basin Science and Knowledge Assistant Director Matthew O'Brien said key ecosystem functions are fundamental to healthy ecosystems and are embedded in key policy arrangements, including the Murray–Darling Basin Plan.
 
“The Murray–Darling Basin is a sizable area and at a Basin-scale we are aware of knowledge gaps. Our focus on this project was to address those gaps to inform improved management and delivery of water for the environment,” he said.
 
“There's been a lot of focus on things like fish or waterbirds. However, we have less understanding of some of the fundamental processes that lead to healthy populations of fish or waterbirds.
 
“The MDBA manages water resources at a scale to achieve healthy, sustainable rivers. Basin-scale, and we're very keen to understand the relationship between flow, hydrology and ecosystem functions. Gaining a Basin-scale perspective on ecosystem functions is a real challenge, and it's one of the innovative aspects of this project.”
 
CSIRO Ecosystem Ecologist Dr Paul McInerney said that, historically, scientific research in Australia has tended to focus on structural aspects of ecosystems, such as estimating the abundance and diversity of animals.
 
“Science has shifted in the last 15 years. We've moved away from just focusing on structural aspects of ecosystems because they don't provide us with information about how the ecosystem functions overall,” he said.  
 
“There was a big opportunity with this project. We explored the role of ecosystem functions in supporting environments of the Murray–Darling Basin. Gaining a mechanistic understanding of ecosystem processes allowed us to better comprehend how these functions impact structural aspects of ecosystems.”

Key project focuses

MDBA General Manager of Science Acquisition Dr Matt Coleman said understanding flow and connectivity as a key driver of ecosystem functions within the Basin, was the central objective of the project to help water managers better plan for a sustainable future.
 
“This deep partnership approach between scientific researchers and government has been a fantastic model for future scientific investment. It ensures that the science will have impact and allow water managers to better prepare for future challenges,” he said.
 
In terms of the project’s broader focus, McInerney said one of the other key aims was to improve the capacity in areas of ecosystem function that are not yet well understood. 

“Part of the project was also about developing ecosystem function metrics that could be quantified and assessed under various programs and policies, like the Murray–Darling Basin Plan or other national water strategies, so that we can assess what we are doing," he said. 

“It was important to start by being very clear on the difference between ecosystem functions and ecosystem services. Ecosystem functions are very specific processes that are important to sustain ecosystems, including things like changes in primary productivity, nutrient cycling or growth rates of animals.”
 
“At the other end of the spectrum, there’s ecosystem services, which relate to benefits that humans receive from natural ecosystems. In our project, we extended ecosystem functions to include research on connectivity and habitat, because although not traditional ‘processes’, they were identified as critical elements of ecosystem functioning.”
 
Another particularly important aspect of the project was to draw on the vast and deep library of data already collected within the Basin, McInerney said.
 
“This project leveraged existing data that has not been used to its full potential yet. We weren't going out on-ground and catching more fish and collecting new data. We were using data sets that we had available and trying to get the most out of them,” he said.

Project facilitation

CSIRO Senior Research Scientist Ashmita Sengupta said the Australian Government, through the Department of Climate Change, Energy and Environment, provided funding for the project. 

The Australian Government has also invested in other monitoring and research across the Murray-Darling Basin, including long-term monitoring data being gathered through the Flow-MER (Monitoring, Evaluation and Research) program that was an important source of data. 

"We merged a lot of novel data sets, like remote sensing data and on-ground data to develop new knowledge, such as long-term hydrological connectivity in the Basin. We developed new methods to map water extent and depth at a Basin scale,” Sengupta said. 

“We then used these water depth and extent layers to generate new data sets such as time since last inundation that were critical inputs into research themes of the project like biological habitat provision. 

“Importantly, a lot of these environmental data sets that we built are available to others for a range of potential applications. An example would be carbon accounting that could utilise the Basin-scale layers of terrestrial gross primary production that provide an improved understanding of carbon dynamics across the Basin.”
 
As there have been many previous studies conducted in the Basin, the team started with a prioritisation process to identify ecosystem function research focus themes with key knowledge gaps but had data available that could be fed into the project, Sengupta said.
 
"We asked ourselves what data we had that was scalable. Also, if some other project was already looking at this data, then we didn't want to duplicate that effort,” she said. 

Given that assessing hydrological connectivity within the Basin was one of the primary objectives of the project, McInerney said many different data sets relating to flow were important to utilise, including magnitude, duration and frequency of inundation.
 
“There is flow and then there is connectivity. Connectivity is when you start looking at connecting the river with its floodplain and the whole landscape and thinking about connectivity from one part of the Basin to the others,” he said.

Project outcomes

So far, six peer reviewed scientific papers have been published in established journals from the project in the past 18 months. Sengupta said those papers have now been cited dozens of times, indicating a high level of interest in the approach taken to this work. 

“Aside from a high level of interest from the scientific community, the project’s output has also been cited in the Productivity Commission’s National Water Reform Inquiry. So the project is helping inform policy at a national level, as well,” she said. 

Dr Coleman said the research has been designed to better inform water management, particularly of environmental water across the Basin – and knowledge is power.
 
“The more we understand about how we can better influence ecosystem function outcomes, the more likely we are to make better decisions,” he said.   
 
“At a higher level, it can also help inform long-term policy settings within the Murray–Darling Basin. We will review the Basin Plan in 2026, and this work will be one of the lines of evidence to inform the review, along with the whole suite of research that has been happening.”
 
Through sponsorship of the R&D Excellence award, WaterRA was delighted to be able to recognise outstanding research taking place across Australia, WaterRA CEO Karen Rouse said.
 
“Research is the foundation for innovation and growth in the sector,” she said. 

“The excellence in this award-winning research lies in its comprehensive, innovative and collaborative approach, which significantly advances the understanding and management of water-dependent ecosystems in the Murray–Darling Basin, ensuring sustainable and effective environmental outcomes.”
 
Interested in nominating an outstanding research project for the Australian Water Association’s awards? Take a look at nomination categories here.