Ecosystem-Based Adaptation (EbA) is a nature-based solution that is gaining significant importance in the context of global climate action (e.g. UNFCCC Paris Agreement, Nationally Determined Contributions, National Adaptation Plans) and biodiversity conservation policies (e.g. the Global Biodiversity Framework (GBF) or the Aichi targets). EbA’s distinctive feature is that it links traditional biodiversity and ecosystem conservation approaches with sustainable socio-economic development. As part of an comprehensive adaptation strategy, EbA provides sustainable and cost-effective solutions for helping people adapt to climate change. “Comprehensive” means that it recognizes the complexity in the impact of climate change on socio-economic-environmental systems, and proposes solutions based on a multi-sectoral and multi-level dialogue. EbA is a people-centric concept, but one that acknowledges that human resilience depends critically on the integrity of ecosystems.

Illustration 1: Qualification criteria for ecosystem-based adaptation measures

In the context of increasing political commitment and funding, it is essential to sharpen the understanding of what qualifies as EbA. The Framework for Defining Qualification Criteria and Quality Standards identifies 3 elements and 5 qualification criteria.

EbA falls under the umbrella concept of Nature-based Solutions (NbS), but is only one form of NbS that focuses specifically on adaptation.

Learn more about EbA as a NbS to adaptation in this factsheet.

The Global Project Mainstreaming EbA has developed a variety of publications on EbA, an overview is available here.

Ecosystem-based approaches to climate change adaptation (and disaster risk reduction, Eco-DRR) use ecosystem services to help people adapt to climate change and reduce disaster risk. This is done through the sustainable management, conservation and restoration of ecosystems and biodiversity. Ecosystems provide crucial services to society, particularly regulating and supporting services that help people adapt and reduce risk (TEEB, 2010):

These are some of the areas of impact and benefits from EbA measures:

• Protection against natural disasters: Healthy ecosystems act as natural barriers to extreme weather events.
  • intact coral reefs and coastal vegetation can dissipate wave action and protect shorelines from erosion;
  • peatlands, marshes and floodplains provide a buffer from floods and water scarcity;
  • forested mountains and slopes can stabilize sediments, providing protection from landslides
• Economic benefits and cost effectiveness: Worldwide surveys have shown that restoration and conservation of ecosystems are generally cost effective.
  • A study in Vietnam indicates that mangrove rehabilitation at village level is generating significantly higher wealth benefits from risk reduction and natural resource utilisation (2.3 million USD over 20 years) compared to dyke construction (only 0.5 million USD) (Köhler and Michaelowa, 2013);
  • Worldwide surveys have shown that restoration and conservation of ecosystems are generally cost effective. The cost-benefit ratio of return of investment of ecosystem restoration may be as high as 3 to 75, compared to the economic damage of ecosystem losses (UNEP, 2020).
• Environmental, economic and social co-benefits: Apart from adaptation and risk reduction, EbA measures generate additional environmental, economic, and social (co-)benefits. They are often referred to as low-regrets options, as they can create benefits regardless of uncertainties in climate projections.
  • Restoration of mangroves:
    
    • can stabilise sediments and protect coastlines from events such as storms, hurricanes, storm surges and coastal erosion.
    • Simultaneously, they can provide new or enlarged habitats for fish and other species, which in turn supports livelihoods
  • Contribution to climate change mitigation targets via:
    • the conservation or restoration of forests and coastal vegetation, and the rewetting of drained peatlands to reduce CO2 emissions
    • the reduction of deforestation and land degradation including peatland drainage, which aids in limiting further greenhouse gas emissions (Duarte et al., 2013; Busch et al., 2015).

Sectoral applications of EbA:

• Water resources:
  
  • Watershed restoration improves water quality and availability with benefits for both rural and urban communities.
  • Wetland conservation regulates the hydrological cycle and reduces flood risks.
• Agriculture:
  
  • The implementation of agroforestry practices increases crop resilience to adverse climatic conditions.
  • Crop diversification and the conservation of agricultural biodiversity improve food security.

EbA in Latin America:

Programs such as “Scaling up Ecosystem-based Adaptation Measures in rural Latin America” seek to increase resilience to climate change in vulnerable communities and ecosystems in Ecuador, Guatemala and Costa Rica. Likewise, the Peruvian program “Escalando AbE Montaña” (Scaling EbA Mountain) has enabled the establishment of experiences in this field in other areas of Latin America.

Urban and rural applications:

Similarly, examples of specific measures could be contextualized according to the environment in which they are developed and impact

• Urban environments:
  • Urban parks and green roofs reduce the heat island effect and improve air quality.
  • Restoring urban riverbanks prevents flooding and creates recreational spaces.
• Rural environments:
  
  • Forest conservation and sustainable agricultural practices protect biodiversity and secure livelihoods.
  • Sustainable rangeland management improves livestock productivity and soil health.

Synergies between AbE and Eco-DRR:

EbA and Eco-DRR (SCBD, 2019) can also enhance biodiversity and nature conservation.

• by improving the resilience of communities to climate change.
• by contributing to the conservation of biodiversity and ecosystem services.
• by promoting community participation and strengthening local capacities.

For a visual understanding of these benefits and applications, please consult also the document “Why working with nature pays off” (GIZ, 2022), which illustrates the interconnections between EbA and the aforementioned sectors.

UNFCCC and the Paris Agreement: Ecosystem-based approaches are a promising option for sustainable and efficient adaptation to climate change. EbA encompasses policies and measures that take into account the role of ecosystem services in reducing societal vulnerability through multi-sectoral and multi-level approaches. The Paris Agreement requires all Parties to engage in adaptation planning and implementation through the national adaptation plan (NAP) process including vulnerability assessments and monitoring and evaluation. The NAP process is an important entry point for EbA as it aims to integrate climate change adaptation into development decisions and investments. It can also form the backbone for implementing the adaptation component of a country’s Nationally Determined Contribution (NDC). Some of the NDCs mention EbA explicitly, while others refer to using ecosystem services as a means for adaptation. There are at least three ways to consider biodiversity and ecosystem services, and thus EbA, in the NAP process:

• Considering climate change in conservation planning: Are conservation objectives threatened by climate change?
• Considering EbA measures when assessing climate change impacts and adaptation options: When should EbA measures be applied (vis-à-vis “grey” infrastructural measures)?
• Considering environmental safeguards for adaptation measures: Are impacts of adaptation measures on ecosystems taken into account?

CBD – Convention on Biological Diversity: The CBD plays a fundamental role for all nature-based approaches. Coherent national policies and aligned reporting on the conventions can enhance the uptake of EbA considerably on national and international levels. Respective policy measures should also translate into subnational planning and implementation. National Biodiversity Strategies and Action Plans (NBSAPs) are the principal instruments for implementing the Convention at the national level (CBD, Article 6). The focus for integration of biodiversity concerns into key sectors in the NBSAPs so far has been on improving environmental outcomes and reducing environmental impacts. However, biodiversity mainstreaming through the NBSAPs can also lead to important outcomes related to climate change adaptation and mitigation, poverty reduction, improved health and wellbeing, and greater social equity.

At the 15th Conference of the Parties of the CBD – COP15, held in Kunming and Montreal – a new Global Biodiversity Framework (GBF) was adopted in December 2022. The GBF provides a strategic vision for 2050 and a new set of 23 international targets for the conservation, protection, restoration and sustainable management of biodiversity and ecosystems until 2030. The role of the framework for biodiversity conservation can be compared to the role of the Paris Agreement for change. Member countries of the CBD will now update their National Biodiversity Strategies and Action Plans (NBSAP) to implement the GBF.

United Nations International Strategy for Disaster Reduction (UNISDR) and the Sendai Framework for Disaster Risk Reduction: The concepts and practice of EbA and Ecosystem-based Disaster Risk Reduction (Eco-DRR) have been developed and refined in recent years as integrative approaches to reduce the risk of climate-related and other types of hazards. These approaches emphasise the importance of biodiversity and ecosystems in reducing risk, and build on other practices such as conservation and ecosystem restoration which seek to increase the resilience of ecosystems for the benefit of people. Eco-DRR operates in line with the Sendai Framework for Disaster Risk Reduction 2015-2030, which encourages “ecosystem-based approaches…to build resilience and reduce disaster risk”. Both EbA and Eco-DRR are part of a multi-disciplinary, cross-cutting approach. Cooperation between the two fields enables stronger results in terms of increased resilience. Shared knowledge and learning, capacity building and a greater ability to design interventions that deliver multiple benefits are just some of the options through which resilience can be improved.

Sustainable Development Goals (SDGs): The SDGs are a universal call to action to end poverty, protect the planet and ensure that all people enjoy peace and prosperity. Many of the SDGs are directly linked to the health and biological diversity of ecosystems and the services they provide. Often, the most disadvantaged and marginalised sections of society are highly dependent on ecosystems to support their livelihoods. EbA can provide sustainable, climate resilient, nature-based solutions that span many of the global challenges the SDGs seek to address, optimising synergies and reducing trade-offs

National Biodiversity Strategy and Action Plan (NBSAP): NBSAPs provide strategic guidance on the protection and management of biodiversity and are the main tool guiding actions to implement the Global Biodiversity Framework at the national level. Countries that are in the revision process of their NBSAPs have the opportunity to draw closely on their NAPs and associated climate risk assessments to understand and incorporate detailed information on ecosystem vulnerabilities and risks under different climate scenarios.

Nationally Determined Contributions (NDC): NDCs were established under the Paris Agreement and are the plans in which each country describes and communicates its post-2020 climate actions. NDCs serve the dual purpose of setting targets and an action plan to reduce emissions and include information on adaptation to climate change. Countries must communicate new NDCs in 2025 that aim to show progress beyond their current NDCs and reflect the highest possible ambition. For countries that have included an adaptation component in their NDCs, the NAP process and its results could be used to improve the quality of adaptation-related information in NDCs.