There are many stories and news around us about how protecting forests can have a positive impact on our current efforts to improve climate change. Well, a new study gives us one more proof about the advantage of forest protection and how important it is.
In the study, which was published in Nature Communications, researchers found that worldwide protected forests have an additional 9.65 billion metric tons of carbon stored in their aboveground biomass compared to ecologically similar unprotected areas.
Different from previous studies which explored similar subjects, this one utilized the highly accurate forest height, structure and surface elevation data produced by NASA’s Global Ecosystem Dynamics Investigation or GEDI.
With GEDI, the team compared the efficacy of protected areas in avoiding emissions to the atmosphere with unprotected areas’ ability to do the same. Then, they tested the assumption that protected areas provide a lot more benefits, like carbon storage and sequestration, than areas that are left as it is.
Lead author Laura Duncanson said that there had been no 3D satellite datasets before, so studies had never mapped forest carbon accurately at this scale.
“Analyzing the data to discover the magnitude of avoided emissions in protected areas shines yet another light on the global importance of forest conservation. We look forward to continuing this work to monitor the future success of protected areas for preserving carbon,” Duncanson said.
According to their data, the current biggest, most climate-positive impact the researchers observed came from the protected, moist broadleaf forest biome in the Brazilian Amazon, with Brazil contributing 36% to the global signal.
Also, the researchers discovered that the amount of aboveground biomass gained from protected areas is roughly equivalent to one year of annual global emissions from fossil fuels. Aboveground biomass is dry mass of woody matter in vegetation that stands above the ground.
A significant difference using GEDI
Previous reports or studies that attempt to quantify protected areas’ biomass content were, to put it simply, unreliable. Because, they had high uncertainties and/or biases. Past satellite biomass products are known to saturate in high biomass forests, such as old-growth protected areas.
With GEDI, the researchers can overcome those limitations.
In this study, the team specifically used height, cover, Plant Area Index (PAI), and Above Ground Biomass Density (AGBD) products from the first 18 months of GEDI mission data, which was collected between April 2019 and September 2020.
Overall, the researchers analyzed more than 400 million 3D structure samples and matched each protected area to ecologically similar unprotected areas based on climate, human pressure, land type, country and other factors.
According to co-author Scott Goetz, these results were the first, long-anticipated, evident proof that protected areas played an important and effective role in sequestering CO2 from the atmosphere than otherwise similar but degraded areas that surround them.
“They were only possible because of systematic spaceborne measurements of canopy structure and aboveground biomass from the GEDI Lidar mission,” Goetz said.
The Intergovernmental Panel on Climate Change (IPCC) reported that protection and restoration efforts are urgently needed to conserve biodiversity and alleviate climate change. According to the IPCC, those efforts are among the top five most effective strategies for mitigating carbon emissions by 2030.
Patrick Roehrdanz, director of Climate Change and Biodiversity at Conservation International who wasn’t involved in the study, said, “This research reflects the importance of the Convention on Biological Diversity target—of achieving 30 percent protection of all ecosystems—as an effective strategy to address more than one of the biggest environmental crises we face: biodiversity loss and climate change.”
Effect not so much as ‘stepping stones’
Speaking of biodiversity loss, protected areas are believed to function as “stepping stones” for species to adjust their ranges as the planet warms. Now, although forest protection has its carbon storing and sequestration, research found that such effects may not apply to the species after all.
“It’s been suggested that these protected areas can serve as safe harbors for species moving or shifting in response to climate change. But we’re finding that may not always be the case,” said Sean Parks, a research ecologist with the USDA Forest Service Rocky Mountain Research Station.
Now, historically, protected areas are a safe haven for preserving biodiversity. But now, since the world is warming, climate is changing, and everything isn’t the way it used to be, the idea of shifting ranges is not easy.
The USD researchers analyzed contemporary climate and human land use data. They found that that many species will not be able to move from one protected area to another in response to climate change. This situation is called climate connectivity failure.
Roughly two thirds of the world’s 30,000 protected areas will experience climate connectivity failure under a 2℃-warming scenario.
Why protected areas may hinder range shifting
There are many things that can contribute to connectivity failure. For instance, protected areas are too far apart or separated by habitats a species cannot pass through—maybe there’s a desert between two mountain ranges.
In another case, the species would have to move through highly developed areas. Or, when our planet warms, some climates may be gone altogether, and the species has nowhere to go.
Co-author of the research Katherine Zeller believed that the research was impressive from a computational standpoint, requiring a supercomputer to run all the data. At the same time, the study came to critical conclusions in terms of the current global protected area system and how it might function in the future
The USA is now contemplating the best ways to achieve its 2030 commitment to protect at least 30% of the planet.
According to Parks, conservation managers could use the study’s findings to prioritize and maximize the probability that species can shift their ranges and more effectively use protected areas as stepping stones under climate change.
Parks also added, as a management strategy, it was also possible to attempt extreme interventions such as transplanting species from one place to another.
Agencies missing the mark on forest protection
Through the studies, we’re reminded that forests are “the lungs of the Earth,” as we all know. And if they’re old, it’s all the more reason to keep them safe.
Experts believe that protecting and restoring mature and old-growth forests on America’s public lands is the cheapest, most effective way to pull carbon from our atmosphere, while at the same time protecting important wildlife habitat and ensuring clean drinking water for communities downstream.
But ever since the threat of wildfire daunts forests in some areas, some experts commented that US agencies focused almost exclusively on forest fire as the only threat facing older forests on public lands today.
“This is odd, because older forests survive fire better than younger ones,” said Jim Furnish, former deputy chief of the USDA Forest Service.
According to the retired deputy chief, US agencies have cooperated with commercial timber sales that keep cutting them down. Instead of focusing on the forest fire, they should address logging and cutting down of the trees.
So, going forward, Furnish believed that keeping forests safe while also preventing fire is the appropriate solution. “The solution lies in conserving ancient forests while reducing fire risk. These are not mutually exclusive goals.”
Looking at the two studies above, Furnish’s suggestion, combined with that of Parks’, may be what we need to boost our efforts to improve climate change and help species with their range shifting.