Humanity is fighting to contain two aggravating crises: the soaring global temperatures and the fall in biodiversity. But people tend to tackle each problem in isolation, for example by deploying green energy and carbon-consuming machines, while protecting ecosystems to preserve them. But in a new report, 50 scientists around the world argue that treating each crisis in isolation means missing out on two-iron solutions that solve both. Humanity cannot solve one without also solving the other.
The report is the product of a four-day virtual workshop attended by researchers from all walks of life and is the result of a collaboration between the United Nations Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services and the Group of intergovernmental experts on climate change. In light of the Paris Agreement, it aims to provide guidance on how campaigns that address biodiversity could also tackle climate change, and vice versa.
The plain language report is expected to prove hugely influential not only among government policymakers and conservation groups, but also among businesses, says Betsy Beymer-Farris, a sustainability scientist at the University of Kentucky, who did not participated in the report but revised it. “It’s hard for businesses or even nation states to truly distill academic literature,” Beymer-Farris explains. The report presents both the science of climate and biodiversity and social science on how to effect change with the help of the people who actually depend on the land for agriculture and grazing. “I was really excited when I looked at the report,” adds Beymer-Farris. “I thought to myself, okay, this is definitely different from what I have seen before, because it is a conscious and serious engagement with a more equitable and just way forward.”
So what might these campaigns look like? Say, for example, that you turn a heavily logged forest into a national park. As trees grow back, they will sequester carbon in their tissues and provide habitat for animals to return. Letting a forest come back naturally, rather than planting a single species of tree to offset some companies’ carbon emissions, makes it more resilient. This is called a nature-based solution, a campaign that both sequesters carbon and provides additional ecological or economic benefit.
“You are helping biodiversity and you can actually generate opportunities for people to use this system sustainably,” says climatologist Hans-Otto Pörtner of the Alfred Wegener Institute in Germany. Pörtner co-chaired the scientific steering committee of the workshop that produced the report. But, he continues, if you create a monoculture, “there’s only one use. And then if that culture that you are using over there is hit by a disaster, you lose that focus altogether. “
A monoculture is less resistant to the ravages of a single disaster, such as a forest fire, or the slower and constant stress of climate change. “When trees are stressed and somewhat weak, they tend to be quite vulnerable to, say, insect attacks and other types of disease,” says report co-author Almuth Arneth, expert in modeling at the Karlsruhe Institute of Technology in Germany. . And if this species is pretty much alone, gets stressed and dies, now all of the new forest is gone.
Biodiversity is a kind of insurance policy against that. A naturally growing forest includes a greater variety of species, and there is a better chance that some of them will survive a one-time disaster or experience ongoing stressors like higher temperatures and more intense droughts. Resilience is built into the ecosystem because it has been functioning for thousands, if not millions of years. Its higher odds of survival also mean it has a better chance of keeping all of its carbon sequestered, keeping it out of the atmosphere, and preventing further global warming.
Stopping humanity’s attacks on ecosystems can also help fight climate change, the study’s authors write. Drying wetlands for agriculture kills species and disrupts an important process of carbon sequestration. Slash-and-burn agriculture in the tropics ignites concentrated underground carbon known as peat, which releases amazing amounts of greenhouse gases. (Yes, peat isn’t 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 more carbon per area than they do. ‘a rainforest, they are home to a wide range of species, and they act as a barrier that absorbs storm surge energy.