Recovered wetlands cut carbon emissions by 39% in a year

Scientists have found that restoring degraded wetlands can reduce carbon emissions by 39% and improve critical ecosystem functions in just one year without triggering a methane surge, often undermining the climate benefits of other wetland types. The discovery challenges traditional ideas about wetland recovery timelines and provides new hope for rapid climate action.

The study, published in the Journal of Environmental Management, highlights floodplain wetlands along the Lodden River in Australia. These riparian systems that make up more than half of the global wetlands, and despite the huge climate, restoration efforts are often overlooked.

The rapid recovery surprised the researchers

Dr. Lukas Schuster from the Center for Natural Solutions at RMIT University led the study, comparing three restored wetlands with three degraded control sites. The recovery speed even caught experienced researchers off guard.

“We found that managing freshwater wetlands for the benefit of carbon also promotes resilience of flooding and drought, highlighting the dual benefits of recovery,” Schuster explained. The recovery site shows measurable improvements to multiple metrics:

• Carbon storage increased by 12% In surface soil within one year
• Soil moisture retention jumped 55% Even if the wetlands are dry
• Nitrogen retention rate increased by 43%improve water quality
• The mulch of native plants expands dramatically In submerged and emerging areas

At the same time, control the wetland to move in the opposite direction. During the monitoring period, carbon emissions increased by 169%, while surface carbon volume decreased by 10%.

Methane problem

What makes these results particularly important is what has not happened. Peatland recovery, while valuable for long-term carbon storage, usually produces peaks of methane, up to 530% and up to 530%. This greenhouse gas tide could offset years or even decades of climate benefits.

Floodplain wetlands did not have this increase in methane in the first year. Schuster’s team found that frequent wetting and drying cycles combined with rapid native plant establishment may prevent anaerobic conditions from methane production.

“Wetlands are natural purification systems that remove nitrogen from carbon in waterways and the atmosphere,” Schuster noted. “Now, we learn more about the important role they play and the speed of their ability to heal.”

The science behind success

Recovery involves two key steps: restoring degraded areas by reconnecting them to river flows and revegetation with 36 native wetland species. This combination has proven to be crucial for rapid ecosystem recovery.

Native plants play the leading role in carbon stubbornness. Leaf waste from Spike-Rush and Swamp Wallaby Grass (such as the spike-style indigenous species) is slower, creating better conditions for soil preservation than invasive ryegrass. The researchers used an innovative “tea bag method” (fuel-standardized green and Rooibos tea samples) to measure the rate of decomposition at various locations.

The link between carbon and ecosystem function proves to be particularly revealed. Soil moisture retention increases carbon storage, which suggests that managing wetlands automatically enhances drought elasticity for climate benefits.

Long-term verification

Another six-year monitoring study confirmed the permanence of these benefits. In wetlands recovered through hydrological recovery alone, surface carbon increased by 53%, indicating that initial gains persist over time.

However, long-term sites do show an increase in methane after six years, possibly due to the accumulation of soil carbon that provides more methane-producing microbial substrates. The researchers stress that enhanced carbon solidification should still exceed these emissions.

Global Impact

Given the statistics on wetland loss, these findings have particular urgency. Since 1700, 21% of the natural wetlands have been lost worldwide, which is 3.4 million square kilometers. Meanwhile, 80% of wastewater enters the environment without treatment, and only 28% of wastewater receives any treatment in middle-income countries.

Schuster highlights the ripple effect: “More nitrogen removed from these wetlands has a positive flow effect on connected waterways. If you manage carbon results, you will gain additional benefits such as drought elasticity and healthier farmland where flora and fauna can thrive.”

Funded by Australia’s Future Drought Fund and conducted by the Arthur Rylah Institute for Environmental Research, the research provides a template for rapid wetland recovery that can be applied globally. The paired experimental design (the sites that will be restored all have downgraded controls, providing a strict model for future recovery projects.

As climate impacts intensify, these findings suggest that wetland recovery represents one of the fastest-acting natural climate solutions available. Instead of waiting for decades of results, land managers realize measurable carbon and ecosystem benefits in a growing season.

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