Nature-based Solutions

Backgrounder

Definition of Nature-based Solutions (NbS)

Nature-based Solutions can be defined as “actions to protect, sustainably manage and restore natural and modified ecosystems in ways that address societal challenges effectively and adaptively, to provide both human well-being and biodiversity benefits,” according to the International Union for Conservation of Nature (IUCN).

NbS targets major challenges such as climate change *, disaster risk, food and water security, biodiversity * loss, and human health.

The following sections discuss these challenges, and show how NbS can address them.

NbS for climate change

• NbS in the form of Ecosystem-based mitigation can strongly contribute to the fight against climate change by preventing the degradation and loss of natural ecosystems.
• Natural and modified ecosystems can effectively combat climate change by acting as “natural carbon sinks,” absorbing and sequestering * carbon dioxide (CO2) emissions. Natural carbon sinks include oceans, soils, and forests, while modified systems that can sequester carbon include agricultural fields managed with practices such as crop rotation, compost amendment, and minimum tillage.
• Conserving, restoring, and sustainably managing forests, wetlands, and oceans plays a critical role in the healthy functioning of the carbon cycle * and the regulation of the planet’s climate. For example, forests can be sustainably managed with a variety of strategies, including establishing protected areas and implementing tree planting programs.
• Ecosystem-based adaptation and Ecosystem-based disaster risk reduction (see below) allow ecosystems to help vulnerable communities, especially those that strongly depend on natural resources, to better adapt * and become more resilient to the adverse effects of climate change, including extreme weather events and climate-related disasters.

NbS for disaster risk reduction

• Major natural disasters in the past decade have shown the role nature can play in reducing risks from natural hazards such as hurricanes and tsunamis*, and demonstrated that taking advantage of ecosystem services is a cost-effective way to reduce risks from disasters. For example, mangroves, and coastal wetlands reduce the risk posed by tsunamis and other sources of coastal flooding.
• Ecosystems such as wetlands, forests, and coastal systems (for example, mangroves) can reduce exposure to natural hazards such as flooding by serving as protective barriers or buffers. They protect infrastructure and property and support quicker recovery of livelihoods.

NbS for food security

• Food security can be defined as “the availability of food that is accessible, safe, locally appropriate, and reliable through time and across space.”
• Solutions to food insecurity must address multiple needs, for example, adapting food systems to environmental change, addressing the root issues that underpin food security (such as poverty and gender-based discrimination), and ensuring that climate change perspectives are considered in all development initiatives.
• NbS can address food insecurity in many ways. These include protecting wild genetic resources (animal and plant), managing wild species (especially fish), and providing irrigation water.
• Focusing on restoring, conserving, and managing ecosystems to deliver ecosystem services can help stabilize food security during natural disasters, climate change, and political instability. Healthy ecosystems such as forests, sand dunes, reefs, and wetlands, perform important functions that reduce disaster risk and play an important role in building community resilience.

NbS for water security

• About four billion people, or 60 percent of the world’s population, live in regions with almost permanent water stress. In these areas, withdrawals of surface and groundwater equal or exceed available supply, meaning that no additional water is available to meet future demand.
• Stresses on water are worsened by water pollution. The large majority (80-90%) of wastewater in developing countries is discharged directly into surface water, causing severe risk to human health.
• Water-related crises can be addressed by NbS through harnessing “natural infrastructure” such as forests, wetlands, and floodplains. For example, coastal mangroves reduce the risk of flooding from tidal changes and disasters such as tsunamis. They also enhance water quality and ecosystem services * by reducing shoreline erosion, which boosts fisheries and reduces water pollution. But nature alone cannot guarantee water security in every situation. Both built and natural infrastructure are needed to effectively manage water resources.
• Ecosystem services related to water are important for human well-being, for food and energy security, for industry, and for the economy, making nature a fundamental building block of water security.

NbS for human health

• The quality of the natural environment, and more specifically of ecosystems, climate, and biodiversity, strongly influences human health, well-being, and social cohesion.
• For example, healthy forests and coral reefs provide a source of pharmaceutical products and other medicines that greatly contribute to human health and well-being.

 

Ecosystem-related approaches within NbS

Nature-based Solutions encompass a range of ecosystem-related approaches, all of which address specific societal challenges. The approaches listed below, most of which existed before the concept of NbS was developed, are practical ways to implement NbS.

Ecosystem-based adaptation

• Ecosystem-based adaptation (EbA) can be defined as the “sustainable management, conservation and restoration of ecosystems, as part of an overall adaptation strategy that takes into account the multiple social, economic and cultural co-benefits for local communities.”
• EbA was developed as a framework to address how ecosystem services can reduce the impacts of climate change on people, biodiversity, and ecosystems.
• EbA can be applied at a variety of levels, but generally provides benefits on a local scale. EbA projects typically include strong community engagement to raise awareness about managing natural resources and increase local support for activities that restore and sustainably manage ecosystems.

Examples of ecosystem-based adaptation include:

• Protecting and restoring wetlands such as streams and lakes that act as sponges, drawing water down through the ground and recharging groundwater supplies, storing it for times of drought.
• Planting trees such as the Mediterranean cypress as natural firebreaks. These species resist wildfires because their leaves retain high levels of water even in extreme heat, and form a wet environment at the base of the trunk.
• Restoring mangroves and coral reefs, which cause waves to break before they hit the shore, reducing their height and force. This reduces the likelihood of waves breaking over into land and the risk of crops suffering salt damage.

Forest landscape restoration

• Forest landscape restoration (FLR) is the ongoing process of restoring ecological functioning and enhancing human well-being across deforested or degraded forest landscapes. FLR is not limited to tree planting, but restores whole landscapes to meet present and future needs and offer multiple benefits and land uses over time.
• FLR does not focus on restoring a landscape to a pre-existing state. Rather, it focuses on improving ecosystem services by, for example, enhancing connections between protected areas, protecting water and soil resources, and reinforcing cultural values.

Green infrastructure

• Ecosystems perform a number of the same functions as conventional grey infrastructure * such as collecting, purifying, storing, and conveying water. For example, “green infrastructure” such as upland forests, aquifers, lakes, and wetlands store water; wetlands filter water; rivers provide transportation; floodplains and wetlands lower flood peaks in downstream cities; and mangroves, coral reefs, and barrier islands protect coasts against storms and flooding.

Ecosystem-based disaster risk reduction (Eco-DRR)

• Ecosystem-based Disaster Risk Reduction (Eco-DRR) is an approach that harnesses the ability of ecosystems to regulate processes (such as climate, air quality, and carbon storage) to mitigate, prevent, or buffer against disasters.
• Eco-DRR approaches focus mainly on minimizing the impacts of hazard events by enhancing people’s capacities to better manage and recover from the impacts of hazards.
• Eco-DRR is closely linked to ecosystem-based approaches to adaptation and mitigation, but is more specific, focusing on particular hazard events (e.g., tsunamis, earthquakes, flooding, and cyclones), and often operates within specified time periods and locations.
• The Eco-DRR approach can be implemented at all scales. Examples include restoring large marshlands to protect adjacent areas from flooding due to hurricanes, and planting trees or other kinds of vegetation on land that is vulnerable to landslides, which both increases the binding capacity of the soil and reduces soil erosion from surface water runoff.

 

Criteria for Nature-based Solutions

The eight NbS criteria listed below cover a variety of factors that are designed to guide NbS practice and implementation, and offer easy-to-follow steps on how to best implement Nature-based Solutions. It should be noted that each criterion includes three to five indicators to measure the strength and effectiveness of solutions.

The criteria and the indicators act as a simple but robust tool that enables practitioners to translate the concept of NbS into targeted activities, strengthen best practices, address shortfalls in implementation, and enable solutions to align with internationally accepted NbS principles.

Users can calculate how well their solution matches the eight criteria and rate whether its match is strong, adequate, weak, or insufficient.

Criterion 1: NbS effectively address societal challenges

Nature-based Solutions should be designed to effectively and efficiently address specific societal challenges.

These might include:

• adapting to and mitigating * climate change,
• reducing the risks of disaster, and
• addressing issues such as ecosystem degradation, biodiversity loss, human health, socio-economic development, food security, and water security.

One or more societal challenges might be the entry point for NbS, but a priority for particular NbS is to provide multiple kinds of benefits and address several challenges.

Criterion 2: Design of NbS is informed by scale

NbS takes scale into account, including geographic scale and the economic, ecological, and societal aspects of the land- or seascape, understanding that the local target area for an NbS is part of larger ecological, economic, and social systems. While individual solutions may focus on specific local areas, the strength, applicability, and responsiveness of the solution should take these broader systems into consideration.

Criterion 3: NbS results in a net gain to biodiversity and ecosystem integrity

The current biodiversity crisis not only threatens rare species with extinction, but also severely degrades many ecosystems, undermining both planetary health and broader human well-being. NbS should improve biological diversity and ecological integrity.

Criteria 4: NbS are economically viable

Keys to the success of any NbS include return on investment, the efficiency and effectiveness of the solution, and equity in the distribution of benefits and costs. This criterion points to the need to ensure that economic viability and sustainability are considered both at the design stage and throughout monitoring and implementation. Otherwise, implementation may not survive project lifetimes.

Criteria 5: NbS are based on inclusive, transparent, and empowering governance processes

This criterion requires that NbS acknowledge, involve, and respond to the concerns of a variety of stakeholders, especially rights holders *. Good governance arrangements include compliance with laws and regulations, and active engagement and empowerment of local communities. They not only reduce the risk to a NBS’s sustainability but also improve acceptance in impacted communities. NbS should recognize and respect pre-existing cultural practices and land uses whenever possible, throughout and beyond the lifecycle of planned activities.

Criteria 6: NbS equitably balance trade-offs between achievement of their primary goal(s) and the continued provision of multiple benefits

In managing land and natural resources, trade-offs are inevitable. Ecosystems provide a wealth of different benefits, and not everyone values each of them in the same way. NbS must acknowledge these trade-offs and follow a fair, transparent, and inclusive process to balance and manage them over both time and geographic space.

Criteria 7: NbS are managed adaptively, based on evidence

Ecosystems may respond in desired ways to NbS. However, NbS activities can also create unintended, unforeseen, and undesirable consequences. Therefore, the implementation process needs to enable adaptive management * as a response to uncertainty.

Criteria 8: NbS are sustainable and mainstreamed within an appropriate jurisdictional context

NbS interventions are designed and managed taking into account long-term sustainability. They also consider, work with, and align with sectoral, national, and other policy frameworks. Strategies to mainstream NbS reach out to individuals (e.g., the public and academics), institutions (e.g., gov’t, business, and NGOs), and global networks (e.g., related to the Sustainable Development Goals, and the Paris Agreement).

Definitions

Adaptive capacity: In the context of climate risk assessments, this refers to the ability of societies and communities to prepare for and respond to the current and future impacts of climate change.

Adaptive management: A structured approach to decision-making that emphasizes accountability and explicitness. Adaptive management is especially useful when there is substantial uncertainty regarding the most appropriate strategy for managing natural resources.

Biodiversity: The variety and variability of living things on earth, encompassing three levels: the diversity of species, diversity within species, and diversity of ecosystems.

Carbon cycle: The process whereby carbon is transferred between the ocean, atmosphere, soil, and living things.

Carbon sequestration: The long-term storage of carbon in plants, soils, geologic formations, and the ocean. Carbon sequestration can occur both naturally and as a result of human activities. It is one method of reducing the amount of carbon dioxide in the atmosphere with the goal of mitigating global climate change.

Climate change adaptation: Actions that make people, ecosystems, and infrastructure less vulnerable to the impacts of climate change.

Climate change mitigation: Actions that reduce emissions of greenhouse gases to the atmosphere.

Climate change: A change in the average climatic conditions—such as temperature and rainfall—in a region over a long period of time.

Climate vulnerability: Encompasses a variety of elements, including sensitivity or susceptibility to harm caused by climate change, and a lack of capacity to cope with and adapt to that harm.

Climate-related risks or hazards: The potential consequences for human or ecological systems from climate change. Risk is a result of the interaction of hazard, vulnerability, and exposure.

Ecosystem services: The benefits people derive from ecosystems. Ecosystem services are divided into four categories: provisioning services (food, raw materials, fresh water, medicines); regulating services (regulating climate and air quality, regulating carbon storage); supporting services (not directly beneficial to humans but essential to ecosystem functioning and therefore indirectly responsible for all other services, including soil formation and plant growth); and cultural services (leisure, tourism, sacred spaces).

Ecosystem: A set of living beings that live within a specific environment and interact with each other and with this environment.

Greenhouse gas: The Earth receives energy from the sun in the form of ultraviolet rays (light) and releases some of this energy back into the atmosphere as infrared rays (heat). Atmospheric gases such as carbon dioxide, methane, and others trap outbound energy in the atmosphere, raising atmospheric temperatures.

Grey infrastructure: Human-engineered infrastructure for water resources. Includes water and wastewater treatment plants, pipelines, dams, seawalls, and reservoirs.

Hazard: The potential for a natural event or human activity to cause loss of life, injury, or other health impacts, as well as damage and loss to property, infrastructure, livelihoods, ecosystems, and environmental resources.

Links between climate change and biodiversity: Climate change has caused significant damage, and increasingly irreversible losses, to land, freshwater, coastal, and ocean ecosystems. This is often referred to as the dual crisis of climate and biodiversity.

Rights holders: Individuals or groups that gain benefits from using resources, are concerned about a particular issue, and/or hold legal or de facto rights to manage or make decisions concerning it.

Where can I find more resources on this topic?

1. Africa Center for Strategic Studies, 2022. African Biodiversity Loss Raises Risk to Human Security. https://africacenter.org/spotlight/african-biodiversity-loss-risk-human-security/#:~:text=Africa’s%20rich%20biodiversity%20is%20under,are%20at%20risk%20of%20extinction
2. Akana, D., 2019. Webinar: Communicating the impacts of climate change on Food and Agriculture. Earth Journalism Network. https://earthjournalism.net/resources/webinar-communicating-the-impacts-of-climate-change-on-food-and-agriculture
3. Angula, M. N. et al, 2021. Strengthening Gender Responsiveness of the Green Climate Fund Ecosystem-Based Adaptation Programme in Namibia. Sustainability, 13 (18). https://doi.org/10.3390/su131810162
4. Cohen-Shacham, E., et al, (eds.), 2016. Nature-based Solutions to address global societal challenges. Gland, Switzerland: IUCN. xiii + 97pp. https://portals.iucn.org/library/sites/library/files/documents/2016-036.pdf
5. Conservation of Biological Diversity 5, 2020. Global Biodiversity Outlook. https://www.cbd.int/gbo/gbo5/publication/gbo-5-en.pdf Summary for Policymakers: https://www.cbd.int/gbo/gbo5/publication/gbo-5-en.pdf
6. Convention on Biological Diversity (CBD), 2010. X/33 Biodiversity and climate change, Decision Adopted by the Conference of the Parties to the Convention on Biological Diversity at its Tenth Meeting; UNEP/CBD/COP/DEC/x/33; 29 October 2010. Nagoya, Japan: Secretariat of Convention on Biological Diversity. https://www.cbd.int/decision/cop/?id=12299
7. Earth Journalism Network, 2016. Climate change and agriculture. Earth Journalism Network. https://earthjournalism.net/resources/climate-change-and-agriculture
8. Earth Journalism Network, 2016. Intergovernmental Panel on climate change. Earth Journalism Network. https://earthjournalism.net/resources/intergovernmental-panel-on-climate-change
9. Earth Journalism Network, 2016. Introduction to climate change. Earth Journalism Network. https://earthjournalism.net/resources/introduction-to-climate-change
10. European Commission, 2015. Biodiversity and climate change. Biodiversity and Climate Change – Environment – European Commission. https://ec.europa.eu/environment/nature/climatechange/index_en.htm#:~:text=Healthy%20ecosystems%20must%20lie%20at,are%20major%20stores%20of%20carbon
11. Global Affairs Canada, 2023. Government of Canada. GAC. https://www.international.gc.ca/world-monde/funding-financement/partnering-climate-partenariats-climat.aspx?lang=eng
12. IUCN, 2020. Global Standard for Nature-based Solutions. A user-friendly framework for the verification, design and scaling up of NbS. First edition. Gland, Switzerland: IUCN. Downloadable at https://portals.iucn.org/library/node/49070
13. IUCN, 2020. Guidance for using the IUCN Global Standard for Nature-based Solutions. A user-friendly framework for the verification, design and scaling up of Nature-based Solutions. First edition. Gland, Switzerland: IUCN. Downloadable at https://portals.iucn.org/library/node/49071
14. IUCN, undated. Nature-based Solutions. https://www.iucn.org/our-work/nature-based-solutions
15. Nature Based Conservancy, 2021. Three things to know about nature-based solutions for Agriculture. The Nature Conservancy. https://www.nature.org/en-us/what-we-do/our-insights/perspectives/three-things-nature-based-solutions-agriculture/
16. Nature Based Solutions Initiative, 2022. Nature-based solutions to climate change. https://nbsguidelines.info/
17. Pausata, F. S., R. et al, 2020. The Greening of the Sahara: Past Changes and Future Implications. One Earth, Vol. 2(3), p 235-250. https://www.sciencedirect.com/science/article/pii/S2590332220301007
18. Renaud, F. G., Sudmeier-Rieux, K., and Estrella, M., 2013. The role of ecosystems in disaster risk reduction. United Nations University Press. Downloadable at https://www.unep.org/resources/publication/role-ecosystems-disaster-risk-reduction
19. Secretariat of the Convention on Biological Diversity, 2008. Biodiversity and Agriculture: Safeguarding Biodiversity and Securing Food for the World. Montreal, 56 pages. https://www.fao.org/fileadmin/templates/soilbiodiversity/Downloadable_files/P020080603430792943555.pdf
20. Shanahan, M., 2016. Seven things every journalist should know about climate change. Earth Journalism Network. https://earthjournalism.net/resources/seven-things-every-journalist-should-know-about-climate-change
21. UNESCO, 2013. Climate change in Africa: a guidebook for journalists, 91 pages. Downloadable at https://www.iied.org/g03710
22. United Nations Environment Programme, 2022. Nature-based Solutions: Opportunities and Challenges for Scaling Up. Nairobi. Downloadable at https://wedocs.unep.org/handle/20.500.11822/40783;jsessionid=15415E686538DB702C504997FC8905D2
23. Vignola R et al, 2015. Ecosystem-based adaptation for smallholder farmers: Definitions, opportunities and constraints. Agriculture, Ecosystems, & Environment, Vol. 211, p. 126-132. https://www.sciencedirect.com/science/article/pii/S0167880915002157
24. World Meteorology Organization, 2022. State of the Climate in Africa 2021. https://library.wmo.int/doc_num.php?explnum_id=10421