Humanity is struggling to contain two compounding crises: skyrocketing global temperatures and plummeting biodiversity. But people tend to tackle each problem on its own, for instance deploying green energies and carbon-eating machines, while roping off ecosystems to preserve them. But in a new report, 50 scientists from around the world argue that treating each crisis in isolation means missing out on two-fer solutions that resolve both. Humanity can’t solve one without also solving the other.
The report is the product of a four-day virtual workshop attended by researchers of all stripes, and is a collaboration between the United Nations’ Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, and the Intergovernmental Panel on Climate Change. In light of the Paris Agreement, it’s meant to provide guidance on how campaigns that address biodiversity might also address climate change, and vice versa.
The plain-language report should prove to be hugely influential not only among governmental policymakers and conservation groups, but also corporations, says Betsy Beymer-Farris, a sustainability scientist at the University of Kentucky, who wasn’t involved in the report but did peer review it. “It’s hard for companies or even nation states to really distill academic literature,” Beymer-Farris says. The report both lays out the climate and biodiversity science and the social science of how to effect change with the help of the people who actually rely on the land for farming and grazing. “I definitely got excited when I reviewed the report,” Beymer-Farris adds. “I thought: Okay, this is definitely different from what I’ve seen before, because it’s a conscious and serious engagement with a more equitable and just way forward.”
So what might these campaigns look like? Say, for instance, you turn a heavily logged forest into a national park. As the trees grow back, they would sequester carbon in their tissues and provide habitat for the return of animals. Letting a forest come back naturally, rather than planting a single species of tree to offset some corporation’s carbon emissions, makes it more resilient. This is known as a nature-based solution, a campaign that both sequesters carbon and provides an extra ecological or economic benefit.
“You’re helping biodiversity, and you may actually generate opportunities for people to use that system sustainably,” says climatologist Hans-Otto Pörtner of the Alfred Wegener Institute in Germany. Pörtner co-chaired the scientific steering committee for the workshop that produced the report. But, he continues, if you create a monoculture, “there’s only one use. And then if that crop that you’re using there is hit by some catastrophe, you’re losing that purpose altogether.”
A monoculture is less resistant to the ravages of a single disaster—like a wildfire—or the slower, constant stress of climate change. “When trees are stressed and sort of weak, they tend to be quite vulnerable to, let’s say, attacks from insects and other sorts of diseases,” says report co-author Almuth Arneth, a modeling expert at the Karlsruhe Institute of Technology in Germany. And if that species is pretty much on its own, and it gets stressed and dies off, now the entire new forest is gone.
Biodiversity is a sort of insurance policy against this. A naturally-growing forest includes a greater variety of species, and the odds are better that some of them will ride out a one-time catastrophe, or endure ongoing stressors like higher temperatures and more intense droughts. Resilience is built into the ecosystem, because it’s been functioning for thousands or even millions of years. Its greater odds of survival also mean that it’s got a better chance of holding onto all of its sequestered carbon, keeping it out of the atmosphere and preventing further global warming.
Halting humanity’s attacks on ecosystems can also help fight climate change, the study’s authors write. The draining of wetlands for agriculture kills off species and disrupts an important process for sequestering carbon. Slash-and-burn agriculture in the tropics ignites concentrated underground carbon known as peat, which releases astonishing amounts of greenhouse gases. (Yes, peat’s not just an Arctic thing.) Protecting coastal mangrove forests comes with a particularly long list of co-benefits, the report points out: They sequester four times the amount of carbon per area as a rainforest, they’re home to a wide range of species, and they act as a barrier that absorbs the energy of storm surges.