Summary:
Restoring degraded floodplain wetlands can cut carbon emissions by nearly 40% and improve drought resilience in just one year, according to a new study published in the Journal of Environmental Management. Unlike restored peatlands, which often release large amounts of methane, the research found that restored riparian wetlands quickly recovered key ecosystem functions without a methane spike.
Led by Dr Lukas Schuster of RMIT University’s Centre for Nature Positive Solutions, the study monitored six wetland sites along the Loddon River in Victoria, Australia. Three sites had been restored by reintroducing water and vegetation, while three remained unrestored. Within a year, the restored wetlands saw a 39% drop in net carbon emissions, a 55% rise in soil moisture, and increases of 12% and 43% in surface organic carbon and nitrogen stocks, respectively.
Restored wetlands also retained more nitrogen and supported native plants whose slower-decomposing litter helped preserve carbon in the soil. A separate site monitored six years after restoration showed a 53% increase in surface organic carbon, highlighting the long-term potential of riparian wetland restoration as a climate solution.
The study emphasizes the value of managing freshwater wetlands for both climate and ecosystem benefits, offering an alternative to peatland-focused approaches.
Restored wetlands reap benefits for climate, drought-resilience after just one year: study
Peatlands are known as top carbon sinks, but can produce up to 530% more methane after restoration, potentially offsetting short-term climate benefits.
Whereas floodplain, or riparian wetlands, which comprise over half of global wetlands, are often overlooked due to their lower carbon storage.
Now a new study published in the Journal of Environmental Management reveals restored floodplain wetlands can recover within a year and show substantial ecosystem benefits rapidly.
New evidence of rapid and lasting benefits
Study lead-author Dr Lukas Schuster from RMIT University’s Centre for Nature Positive Solutions said the scale and pace of ecosystem benefits revealed within just one year of restoration provide a clear case for action.
“Restoring wetlands could be a secret weapon against climate change,” he said. “We found managing freshwater wetlands for carbon benefits also boosts flood and drought resilience, highlighting the dual benefits of restoration.”
While rewetting and revegetation reduced carbon emissions by 39%, net carbon emissions from the unrestored control wetlands increased by 169% over the monitoring period. Surface organic carbon stocks, where carbon is stored in plant roots and soil, increased by 12% within one year in restored sites and decreased by 10% in control sites, showing the difference in carbon sequestration potential.
Restored wetlands retained more water in the area, with soil moisture levels increasing by 55%, even after the wetlands themselves had dried, showing drought mitigation potential. Schuster said increased water retention was linked to improved surface carbon storage in freshwater wetlands.
“We observed a vital link between carbon dynamics and ecosystem function,” he said. “Wetlands are nature’s purification system, removing nitrogen from waterways and carbon from the atmosphere. Now we know even more about the important role they play and how quickly their recovery can be, it’s time to act.”
Freshwater wetlands, covering less than 10% of the Earth’s surface, contribute up to 25% of global methane emissions. Despite this, they hold significant potential as long-term carbon sinks, playing a crucial role in the global carbon cycle. For the study, researchers compared three degraded with three restored wetlands along the Loddon River in Victoria, Australia, measuring native plant cover, carbon cycling and ecosystem function.
In the restored wetlands, native plant cover increased significantly, with leaf litter from two dominant native wetland species decomposing more slowly than that of an invasive grass species, suggesting a greater potential for carbon preservation in the soil. With 45% more nitrogen retained in the soil, restored wetlands showed increased nutrient cycling, which is linked to improved water quality and helps prevent ecosystem disruption like harmful algal blooms, oxygen depletion and contamination.
Schuster said this was important because riparian wetlands are connected to other ecosystems like rivers and streams. “More nitrogen removed from these wetlands has a positive flow-on effect to connected waterways,” he said. “If you manage the carbon outcome, you get other benefits like drought resilience and healthier farmland where flora and fauna can thrive. We’ve shown wetland restoration pays off, so we hope this study will inform future land management policies.”
A floodplain wetland was also monitored six years after it was restored by reintroducing water flow, finding surface organic carbon stocks increased by 53%, demonstrating lasting benefits.
The research was led by RMIT’s Centre for Nature Positive Solutions, which focuses on addressing urgent environmental challenges from climate change to pollution and biodiversity loss.
Researchers from the Victorian Government’s premier biodiversity research institute, the Arthur Rylah Institute for Environmental Research, were also involved.
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The study was funded by the Australian Government’s Future Drought Fund, Deakin University’s Blue Sky Fund and the Australian Research Council.
Journal Reference:
Lukas Schuster, Stacey Trevathan-Tackett, Paul Carnell, Kay Morris, Bryan Mole, Martino E. Malerba, ‘Restoring riparian wetlands for carbon and nitrogen benefits and other critical ecosystem functions’, Journal of Environmental Management 391, 126433 (2025). DOI: 10.1016/j.jenvman.2025.126433
Article Source:
Press Release/Material by RMIT University
Featured image credit: RMIT University
