However, the project at Chesapeake Bay is of a scale rarely seen in ecosystem restoration. Many current Nature-based Solutions are small scale and exist in isolation, and carbon sequestration is a side benefit, not the primary objective. If Nature-based Solutions are to make a major contribution to the prevention or mitigation of climate impacts, more large-scale or global-scale projects are needed. With some degree of warming already inevitable, scaled-up NbS projects that help us adapt to climate change are urgently needed too.

Finding funds

First and foremost is the issue of investment. A recent assessment of the NbS funding landscape published by the World Resources Institute (WRI) showed that only a small percentage of international public climate finance has been flowing to natural solutions for adaptation to climate change: somewhere between 0.6% and 1.4% in 2018.

It’s not clear that policymakers fully appreciate the value of natural capital yet, and the services the natural world provides. Mangroves, for example, provide flood protection and are extremely cost-effective when compared to the building or maintenance of grey infrastructure (such as sea walls), while also storing carbon and helping to boost local biodiversity. One study found that, across 59 countries, mangroves alone can help save an estimated US$65bn annually in avoided losses in infrastructure and human systems, including health.

Initiatives like the Nature-based Infrastructure Global Resource Centre are helping conservation organisations demonstrate solid business cases for investment in NbS. The centre, set up by the International Institute for Sustainable Development, provides assessments of the potential economic value of nature-based infrastructure projects, and analyses how non-natural infrastructure projects could benefit from adding or completely replacing with a Nature-based Solution.

According to the WRI, more investment in NbS would enable a “critical mass of pilots and early-stage projects to take place around the world, in some of the most challenging conditions”. Once these grant-funded opportunities demonstrate NbS can work for different circumstances or objectives, programmes could eventually become self-sustaining, as they are in countries such as Costa Rica, where NbS are financed from within the government’s budget.

Dr Richard Lilley Photo: Dr Richard Lilley

However, Dr Richard Lilley, co-founder of Project Seagrass, warns that as NbS scale up, one-size-fits-all approaches become less likely to succeed. “There’s a real nuance to Nature-based Solutions, where different habitats, or even the same habitat, will offer different ecosystem servicesin different locations,” he says. “We need to be planting trees and putting in above-ground biomass across the planet for sure – but they need to be appropriate trees, the right species in the right places. Similarly, in the sea, we need that nuance – different solutions will be appropriate in different places or conditions.”

Around the world, it is often indigenous peoples and local communities that are the stewards of local ecosystems – therefore Nature-based Solutions need to include and benefit them too.

Scaling up at speed

Adapting projects to individual communities and engaging people through citizen science is essential, says Lilley. “You need everyone on board with the journey that the local area is going to go through. Community is essential to this. Not including communities is the single biggest risk factor. When someone gets involved, they [develop] this sense of ownership.”

Restoring complex ecosystems such as peatlands, forests, mangroves or seagrass meadows is no quick fix. But the need for Nature-based Solutions is urgent. So how do organisations move projects forward at pace with so many stakeholders, scientific evidence and intersecting factors to consider?

Lilley says there has to be an iterative approach to projects if we are to scale up at the speed required. When projects are developed on a grand scale, intricacies emerge that can’t always be foreseen.

Photo: LEWIS M JEFFERIES; ILCP

Future-proofing nature

With unpredictable change ahead, NbS need to be more dynamic, adaptable and forward-looking than traditional conservation programmes. The parameters of the project may not remain constant and the project should aim to tackle longer-term
threats, like desertification and sea level rise.

Finally, and perhaps most obviously, we need to be clear about what an NbS actually is. If Nature-based Solutions are to contribute a third of climate mitigation efforts by 2030, a precise definition is required to ensure that the most effective, impactful and rigorously monitored projects are prioritised.

First defined by IUCN in 2016, the definition of NbS has since evolved slightly to incorporate the diversity of ecosystems and complexities of global societal challenges being tackled. In 2022, the United Nations Environment Assembly (UNEA) delivered this multilaterally-agreed definition: “Nature-based Solutions are actions to protect, conserve, restore, sustainably use and manage natural or modified terrestrial, freshwater, coastal and marine ecosystems, which address social, economic and environmental challenges effectively and adaptively, while simultaneously providing human wellbeing, ecosystem services, resilience and biodiversity benefits.’’