UVA environmental scientists are continuing to document the value of seagrass meadows for mitigating climate change. They conduct much of their research in the seaside bays of Virginia’s Eastern Shore, working on the largest seagrass restoration project in the world. McGlathery directs UVA’s Long-Term Ecological Research project there.
Last week her former graduate student, Matthew Oreska, published a paper in the journal Scientific Reports that is the first to provide a full accounting of the net carbon gain that restored seagrasses can provide on the carbon trading market. His collaborators included McGlathery, environmental sciences professor Peter Berg and graduate students Lillian Aoki and Amelie Berger.
“Much of the current climate change discussion concerns efforts to reduce the amount of greenhouse gas pollution going into the atmosphere, but efforts to draw some of that pollution out of the atmosphere are equally helpful and may become increasingly important in coming years,” Oreska said. “Seagrass restoration projects and other agriculture, forestry and land-use projects that restore a plant community, therefore, provide a relatively straightforward approach for generating negative emissions.”
Seagrasses, such as eelgrass and turtle grass, live in shallow water in bays and estuaries. They provide nursery habitat for a wide range of fishes, shellfish, mollusks and more. They are crucial to healthy coastal ecosystems in many areas worldwide. They also “sequester” or absorb atmospheric carbon dioxide and store it within their leaves, stems and roots, and ultimately into the soil on which they live.
Carbon dioxide, considered a “greenhouse gas,” is produced naturally, but also as a result of the burning of fuels such as coal and gasoline. Excess carbon dioxide in the atmosphere can contribute to and accelerate climate warming. But natural “carbon sinks,” such as forests, salt marshes and seagrasses, can help alleviate the problem by capturing excess carbon and storing it within those systems.
The new UVA paper demonstrates the value of preserving and restoring these “blue carbon” ecosystems, providing a means for naturally removing and storing carbon for perhaps centuries.
“Both nature-based and technological strategies can put climate change in reverse by removing atmospheric carbon,” McGlathery said. “This is critical if we are to meet the Paris Climate Agreement goal of not exceeding 1.5 to 2 degrees Celsius of additional climate warming by the year 2100.”
The research is an example of the connection between science and policy, McGlathery said. Her research group has helped develop an international protocol by which carbon-producing companies can buy carbon credits in the voluntary carbon market and use those credits to pay for seagrass restoration. This is managed by the international environmental sustainability group Verra.
“Credit trading allows corporations and individuals to offset their carbon footprint; and these investments provide for further seagrass restoration,” McGlathery said.
This same research also has informed policy in Virginia. In March, Gov. Ralph Northam signed a bill, largely based on the UVA research, that allows carbon market participation for seagrasses and other aquatic vegetation.
“This is exactly the kind of actionable research that we promote through the Environmental Resilience Institute,” McGlathery said. “The new policy benefits our partner organization on the Eastern Shore, the Nature Conservancy, and others in generating funding for more seagrass restoration. It’s a win-win.”