Skip to content

What are nature-based solutions and why do they matter?

January 20, 2022
Catskill Mountains over Ashokan Reservoir: the watershed provides New York City with the “champagne of drinking water”. Image: John Cudworth | Flickr Creative Commons

Open a tap in New York City and flows what many locals call the “champagne of drinking water”. New York is one of the few cities in the USA with a public drinking water supply that doesn’t rely on expensive filtration plants. And the reason for this “champagne” supply? The network of forests, streams, lakes and reservoirs in Catskill Mountains watershed to the north of the city. Estimates suggest that if it wasn’t for the natural filtration processes occurring in the watershed the city would have to invest more than $10 billion in water filtration facilities.

The natural processes occurring in the Catskill watershed thus provide a range of environmental, social and economic benefits to local communities. Such aspirations are at the heart of a recent turn in environmental management towards so-called “nature-based solutions”, which aim to use natural processes to help tackle socio-environmental challenges such as climate change, biodiversity loss and flooding.

Nature-based solutions: environments, societies, economies

Nature-based solutions are often designed to bring benefits to both people and nature. For example, planting native forests in watersheds can help naturally filter water supplies and buffer flooding, whilst restoring peat bogs can help provide biodiversity habitat and boost carbon storage. The IUCN estimates that such nature-based solutions have the potential to supply up to 37% of global climate change mitigation needs.

A commonly-cited definition of nature-based solutions from the IUCN highlights the focus on nature-society benefits, “Nature-based solutions are actions to protect, sustainably manage, and restore natural and modified ecosystems that address societal challenges effectively and adaptively, simultaneously providing human wellbeing and biodiversity benefits.”

In this definition we see the traces of linked concepts of sustainability and ecosystem services that have informed global environmentalism in recent decades. However, what is new about nature-based solutions is the impetus they provide for policy makers to support large-scale and ambitious environmental restoration to address contemporary issues. In so doing, the nature-based solutions concept aims to provide clear economic and social rationales for the value of protecting and restoring natural environments.

Wetland restoration in Sweden through the MERLIN project aims to enhance biodiversity and carbon storage. Image: MERLIN

Supporting resilient ‘green’ societies and economies

As a result, nature-based solutions have become a central part of contemporary EU environmental policy, such as the European Green Deal, and in the Horizon 2020 programme. The European Commission defines nature-based solutions as, “Solutions that are inspired and supported by nature, which are cost-effective, simultaneously provide environmental, social and economic benefits and help build resilience. Such solutions bring more, and more diverse, nature and natural features and processes into cities, landscapes and seascapes, through locally adapted, resource-efficient and systemic interventions.”

Like the IUCN definition, we see the emphasis on the multiple benefits of natural systems, however, the EC definition adds the concept of building resilience into both urban and rural landscapes. Resilience here refers not only to how ecosystems will respond to emerging challenges such as climate change, but also how job provision and economic growth might be sustained within increasingly “green economies”. In Europe, therefore, nature-based solutions represent a significant tool for transformative change towards greener, climate-resilient societies.

Nature-based solutions are increasingly being deployed in freshwater environments, notably in the 17 flagship restoration sites across Europe managed by the MERLIN project. For example, the restoration of peatlands and wetlands in Sweden is targeted at increasing carbon storage and enhancing biodiversity (such as through the reintroduction of beavers). Similarly, the restoration of natural river channels and floodplains in the highly-modified Emscher catchment in Germany is designed to improve habitat, reduce flooding and create new spaces for recreation.

The IUCN Global Standard for Nature-based Solutions. Image: IUCN

Nature-based solutions: questions, issues and futures

Nature-based solutions are increasingly being adopted in environmental policy and management, not only in Europe but across the world. But there remain significant questions for their adoption. Where should the line be drawn as to what counts as a ‘natural’ intervention? Which communities and stakeholders (human or non-human) might nature-based solutions benefit, and which might be overlooked?

In complex and often-uncertain contemporary landscapes, can all the potential pros and cons of a particular nature-based solution be fully considered? In addition to their benefits, could nature-based solutions unintentionally foster negative ‘ecosystem disservices’ in a landscape? And, significantly, given the centrality of economic benefits to the concept, can nature-based solutions remain apart from issues of corporate ‘greenwashing’ through schemes such as carbon offsetting through tree planting?

In response to such ongoing questions, in 2020 the IUCN provided the first ‘Global Standard for Nature-based Solutions’, offering eight specific criteria for their application. First, there is the need to clearly identify the social challenge to which the solution responds. Second, the value of the solution needs to be considered in terms of its effects across entire landscapes. Third, fourth and fifth are focused on the key pillars of sustainable development: environment sustainability, social equity and economic viability.

The sixth criterion addresses the need to identify trade-offs in decision-making between everyone affected by the solution, on both short- and long-timescales. Seventh, the need for an adaptive approach to learning through management is highlighted in designing solutions which evolve and improve over time. Finally, the IUCN highlight the need to mainstream nature-based solutions within national and international policy in order to underpin their long-term success. The IUCN criteria form the basis of a self-assessment tool for environmental managers using nature-based solutions.

Nature-based solutions offer rich potential in gaining support for environmental protection and restoration, by placing nature at the heart of social life. We will continue to follow their development and application, both in Europe and beyond, on this blog in the coming years.


This article is supported by the MERLIN project.

Comments are closed.