Climate change has its well-known target of limiting global warming to below 2°C and pursuing efforts to limit it to 1.5°C. Is it time to create similar goals for biodiversity – the world’s diminishing community of animals, plants, and other organisms – or is nature just too complex?
With the U.N. Convention on Biological Diversity (CBD) in the process of drawing up recommendations for an international agreement later this year, a group of leading scientists met in the end of February, to study what is the best scientific consensus in the creation of biodiversity goals. The workshop was held in Davos, Switzerland, and chaired by Sandra Díaz, professor of ecology at Córdoba National University, and co-chair of the Global Assessment of IPBES.
The moves come against a backdrop of serious declines in nature worldwide. IPBES suggests, for example, that around 25 percent of plants and animals other than insects are currently threatened with extinction.
“We want to create a message that the world will grasp, that will build change and be true to science,” Josh Tewksbury, an ecologist who directs the Colorado global hub of the Future Earth network of scientists, said of the attempts to come up with plausible targets.
The complexity of achieving the goal, however, was underlined by the range of specialties among the roughly 50 scientists at the meeting or working with it online. They included coral reefs, islands, plants, scientific modelling, land use, aquatic ecology, social science, genetic diversity, and economics.
After four days, the group, which was brought together by the Earth Commission of leading environmental scientists (hosted by Future Earth), came up with series of conclusions to be sent to CBD advisers at the end of March. The idea is to make a concrete science-based contribution to an agreement on protecting biodiversity expected to be reached by 196 countries in October in Kunming.
The scientists offered key elements for setting goals to halt declines in ecosystems, species, and genetic diversity, as well as improving nature’s contributions to people – all areas being considered by the CBD.
Getting there – and defining the science behind it all – was far from simple. Biodiversity is self-definingly diverse – in some ways a far more difficult subject to come to terms with than global warming, particularly when it comes to targets.
“It’s very complicated for two main reasons,” said David Obura, a member of the Earth Commission who is director of CORDIO East Africa, a group seeking to protect coral reefs and marine systems in the region.
“One is because life is complicated… Secondly, we haven’t the ability to measure all the different facets nor the global scale (of life),” he said.
This led the scientists into a series of discussions about effective biodiversity goals, including whether there should be an overarching one. The consensus was that one apex goal (like the climate temperature goal) is unlikely to work for biodiversity.
There were also debates about whether a goal of “no net loss” in biodiversity by 2030 – as being broached by the CBD – was the right way to go. Essentially a stand-still idea – not letting things get worse rather than reversing degradation over all – some believed it was not ambitious enough, with one saying 2020-2030 should be considered “the restoration decade”.
While “no net loss” allows for the compensation of future degradation, such compensating is difficult and restoration can take a very long time and may, in some cases, not be possible at all. It was, however, noted that biodiversity is on such a decline that halting the loss is in itself an achievement. Therefore, at the end, the group concluded that no net loss may be an appropriate target – if for critical ecosystems a “no loss” is chosen instead as the minimum.
The meeting’s methodology was to break into workshops on the various goals, drawing from the attendees’ own expertise and that of published research.
This led to critical discussions about things that at first might seem obvious, but actually aren’t. What, for example, really comprises an ecosystem? What policy consequences does including the word “natural” have? How do you define a benefit to people in one place that is a setback in another?
Berta Martín-López, a professor of sustainability science at Germany’s Leuphana University, noted that in her working group coming up with recommendations to cover the sustainability of nature’s contributions to people was rife with difficulty.
It included how to get hard evidence on how nature provides benefits to humanity, differentiating between what nature does and humans can do, and how to assess who are the winners and losers of those benefits.
She said, however, that it was worth the struggle, because the Earth Commission meeting was highlighting the importance of nature to all.
It was also necessary. Fabrice DeClerck – a member of the Earth Commission, senior scientist at the Alliance of Biodiversity & CIAT, and science director of the EAT Foundation – noted that biodiversity has both intrinsic values and critical functional values for the Earth.
“Biodiversity is akin to a computer’s operating system,” he said. “It is what allows us to run functions and operations. With the loss of biodiversity that we are seeing, both of intact nature, but also of nature in working landscapes or agricultural lands, we are at a critical point where we are really losing nature’s capacity to provide those essential services that contribute to human well-being such as producing nutritious foods, ensuring clean water, and regulating climate.”
The workshop was organized by the Earth Commissioners Sandra Díaz, David Obura, Peter Verburg, and Fabrice DeClerck, in collaboration with David Cooper from CBD, Cornelia Krug, BioDISCOVERY, Eva Spehn, Global Mountain Biodiversity Assessment and Swiss Biodiversity Forum, and from the Future Earth Global Secretariat Noelia Zafra-Calvo, Wendy Broadgate, Juan Rocha, Josh Tewksbury, and Susanna Dobrota.