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. Convention on Biological Diversity Strategic Plan 2011-2020, 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 overall strategy for helping people adapt to climate change. EbA is a people-centric concept, but one that acknowledges that human resilience depends critically on the integrity of ecosystems.

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): 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.

Ecosystems can also prolong the sustainability and lifetime of built infrastructure, thus protecting investments in engineered defenses (hybrid solutions) – such as restoring salt marshes adjacent to sea walls (source: Voluntary guidelines for EbA/Eco-DRR). 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).

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. Mangrove restoration, for instance, can stabilise sediments and protect coastlines. Simultaneously, the restored mangroves provide new or enlarged habitats for fish and other species, which in turn supports livelihoods. EbA as well as Eco-DRR can also enhance biodiversity and nature conservation. Furthermore, they can contribute to climate change mitigation targets via: i) the conservation or restoration of forests and coastal vegetation, and the rewetting of drained peatlands to reduce CO2 emissions; ii) 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).

Introducing EbA measures is not without challenges, however. Since ecosystems are complex and interconnected with the social system (especially livelihoods), these measures need to contain targeted adaptation strategies that address issues in the ecological, social and economic context. Given that ecosystems span from the local to transboundary scale, EbA measures need to consider a wide range of actors from a variety of sectors. Consequently, EbA projects are influenced by stakeholder relationships and existing power structures. Addressing justice issues is therefore crucial, not only to avoid fragmented solutions that increase injustices, but also to enhance the effectiveness and sustainability of EbA projects as a whole.

The Global Project Mainstreaming EbA has developed a variety of publications on the topic of Just EbA such as “Climate Justice in Ecosystem-based Adaptation: The case of Soc Trang coastal zone, Vietnam“. The collection of publications is available here.

Climate change threatens ecosystems as well as their services and endangers human development worldwide. The ultimate goal of mainstreaming ecosystem-based approaches is establishing EbA (and Ecosystem-based Disaster Risk reduction, Eco-DRR) as standard development practices in order to avoid and manage current and future climate risk. This means “doing things differently in the face of climate change” and requires integrating ecosystem-based adaptation and risk reduction into development decisions at all levels and in all areas at risk.

To learn more about EbA and its mainstreaming, the EbA e-learning course is now available on edX. Additionally, the EbA Mainstreaming Cycle shown below provides further insights into EbA mainstreaming.

Based on its operational experience worldwide in promoting (ecosystem-based) adaptation, GIZ’s framework for mainstreaming EbA employs an iterative six-step approach (known as the adaptation mainstreaming cycle, see diagram below). It includes the elements of mainstreaming and provides tools and methods that can be utilized at each step. This guidance is in line with the Voluntary guidelines for the design and effective implementation of ecosystem-based approaches to climate change adaptation and disaster risk reduction developed upon request by the CBD Conference of the Parties (COP) in its decision XIII/4. GIZ contributed to the development of the guidelines.

The adaptation mainstreaming cycle (GIZ 2019, adapted from CBD 2019)

Step 1: The use of a climate and ecosystem lens can help to define the context of EbA mainstreaming such as the problem definition (e.g. lack of water), identifying the system of interest (e.g. a watershed, sector or policy), and understanding the interconnections between human and natural systems.

Step 2: A vulnerability or climate risk assessment provides the basis for adaptation planning. The assessments should be conducted in an inclusive way considering local sources of knowledge and inter-linkages between social, ecological and economic systems should be considered. GIZ’s Risk Assessment Guidebook provides guidance for such assessments.

Steps 3&4: Informed by the climate risk assessment, the identification and selection of suitable EbA measures can be based on potential effectiveness, co-benefits, stakeholder buy-in, feasibility and other criteria. Instruments that support this process are cost-benefit and multi-criteria analysis which should be conducted in a participatory manner.

Step 5: The implementation requires robust planning, for example based on a theory of change, and engagement of suitable personnel. Coordination mechanisms with government partners and other actors need to be established.

Step 6: A monitoring and evaluation system needs to be designed based on four key considerations, namely the M&E purpose, the intended information and target audience and the available resources. A guidance manual on the design of M&E systems for EbA measures has been co-developed by GIZ.

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.

For further information, see the Voluntary guidelines for the design and effective implementation of ecosystem-based approaches to climate change adaptation and disaster risk reduction

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