Nature-based Solutions for Major Societal Challenges

Session 1: Nature-based Solutions and Their Importance

 

What are Nature-based Solutions?

‘Nature-based Solutions’ (NbS) is an emerging concept from the beginning of the millennium for enhancing ecosystem services provision (see Box 1) and addressing major societal challenges. It was formally introduced by the World Bank in its 2008 report ‘Biodiversity, Climate Change and Adaptation: Nature-based Solutions from the World Bank Portfolio’, highlighting the role of biodiversity conservation in climate adaptation and mitigation. In 2009, the International Union for Conservation of Nature (IUCN) promoted NbS in its position paper to the 15th Conference of Parties to the United Nations Framework Convention on Climate Change (UNFCCC COP15).

The concept of NbS is increasingly being developed and promoted by organisations such as the IUCN, the European Commission, and the United Nations Environment Programme (UNEP). The definitions of NbS by the IUCN, the United Nations Environment Assembly (UNEA), and the European Commission all emphasise that NbS simultaneously benefit both humans and the environment. While the IUCN and UNEA’s definitions of NbS, which emphasise the importance of nature conservation and restoration, are widely quoted around the world, the European Commission’s definition of NbS covers nature-inspired solutions (Table 1). The UNEA recognises that NbS are important for achieving the United Nations Sustainable Development Goals (UNSDGs) (UNEA, 2022).

 

Table 1: Definitions of NbS

Definition by IUCN	Definition by the United Nations Environment Assembly (UNEA)	Definition by the European Commission
‘Nature-based Solutions are defined as “actions to protect, sustainably manage, and restore natural or modified ecosystems, that address societal challenges effectively and adaptively, simultaneously providing human well-being and biodiversity benefits.”’ (IUCN, 2016)	‘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 well-being, ecosystem services, resilience and biodiversity benefits. (UNEA, 2022)	‘Nature-based solutions 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.’ (European Commission: Directorate-General for Research and Innovation, 2015; European Commission: Directorate-General for Research and Innovation, n.d.)

 

According to the IUCN, NbS use the power of functioning ecosystems as infrastructure to deliver natural services that benefit both society and the environment (IUCN, 2020b). The operational framework of NbS is grounded in the ecosystem approach, which the Convention on Biological Diversity COP 5 Decision V/6 defines as ‘a strategy for the integrated management of land, water and living resources that promotes conservation and sustainable use in an equitable way’. IUCN considers NbS an umbrella concept covering a full range of ecosystem-based approaches (Cohen-Shacham et al., 2019) (see Table 2) that address societal challenges such as climate change, disaster risk, biodiversity loss and ecosystem degradation, food security, water security, human health, and economic and social development (IUCN, 2020a).

 

Box 1: Ecosystem Services Ecosystem services are the benefits people obtain from ecosystems. According to the 2005 Millennium Ecosystem Assessment, there are four categories of ecosystem services: Provisioning services, Regulating services, Cultural services, and Supporting services (Alcamo et al., 2003):

 

Table 2: Approaches under the NbS Umbrella

Category	Approach	Example
Restorative	Ecological restoration	Restoration of a contaminated river basin (Cohen-Shacham et al., 2016)
Restorative	Ecological engineering	Use of species that trap sediment for coastal protection of a sandy shore (Borsje et al., 2011)
Restorative	Forest landscape restoration	Large-scale restoration in the Loess Plateau, China (Lü et al., 2012)
Issue-specific	Ecosystem-based adaptation	Renaturation of rivers or canals to attenuate flooding, or the replanting of forests with more future climate-tolerant species to adapt to climate change (Doswald & Osti, 2011)
Issue-specific	Ecosystem-based mitigation	Restoration of forests to sequester carbon emissions for mitigating climate change (The Global Commission on the Economy and Climate, 2014)
Issue-specific	Ecosystem-based disaster risk reduction	Restoration of wetlands to reduce storm surge (Wamsley et al., 2010)
Infrastructure	Natural infrastructure	Conservation of watersheds for water source protection (Krchnak et al., 2011)
Infrastructure	Green infrastructure	Establishment of a large natural park, Collserola Park, in the city of Barcelona (Ajuntament de Barcelona, 2013)
Management	Integrated coastal zone management	Mangrove restoration together with other structural and non-structural measures for flood risk reduction in Semarang, Indonesia (Nehren et al., 2014)
Management	Integrated natural resources management	Combination of land rehabilitation with innovative financing, value chains, and inclusive planning at the flooding and landslide prone Sebeya catchment in Rwanda (IUCN GSAP, n.d.)
Management	Agroecology / Regenerative agriculture	Application of regenerative agriculture in the ‘Andhra Pradesh Zero Budget Natural Farming’ project in India to improve the livelihoods of farmers and resilience of crops and land (APCNF, n.d.)
Protection	Area-based conservation	Protection of private forest patches at Jabarkhet Nature Reserve in Mussoorie, India (Fernandes, et al., 2022).

 

Continue to 'Session 2: NbS Principles, Criteria and Indicators'

 

 

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