Ecosystem-based Adaptation "at a glance"
People worldwide depend on intact ecosystems and the services they provide, such as soil fertility, clean water and food as well as buffering of extreme weather events. This is especially true for poor people in developing countries, whose livelihoods are closely linked to natural resources.
Climate change is one of the major causes of changes and deterioration in ecosystem services and its impact will most likely increase in the future (Millennium Ecosystem Assessment 2005). At the same time, functioning ecosystems help people to mitigate and more importantly to adapt to climate change at local, national, regional, and global levels – this concept which includes a long-term and climate risk oriented approach is referred to as “ecosystem-based adaptation” (EbA).
The idea of ecosystem-based adaptation originally arose in NGO and intergovernmental organization circles as “natural solutions to climate change”. EbA has evolved into an important link between the three Rio Conventions: the United Nations Framework Convention on Climate Change (UNFCCC), the Convention on Biological Diversity (CBD) and the United Nations Convention to Combat Desertification (UNCCD). Of the three Rio conventions, the CBD concerns itself the most with EbA.
The CBD definition of EbA is used by a wide range of actors:
“Ecosystem-based adaptation is the use of biodiversity and ecosystem servicesas part of an overall adaptation strategy to help people to adapt to the adverse effects of climate change.” CBD 2009
Hence, ecosystem-based adaptation was defined as increasing the adaptive capacity of people through the sustainable use and conservation of ecosystems. In contrast to common natural resources and biodiversity management approaches, EbA is explicitly part of an overall adaptation strategy. Although EbA measures use ecosystems to adapt to climate change, EbA still is an anthropogenic approach which particularly utilizes the ability of ecosystems to provide so called ecosystem services. They are also referred to as “green infrastructure” and can be seen as complementary to or substitutes of hard (“grey” or concrete-based) infrastructural measures.
For example ecosystems are able to generate direct services such as food and building material as well as indirect services like water treatment or pollination. An overview of ecosystem services as described by The Economics of Ecosystems and Biodiversity (TEEB).
However technical measures alone are not sufficient for adaptation but have be complemented with capacity development, awareness raising as well as research for example on the importance of ecosystems and the services they provide for human well-being.
EbA is a nature-based solution which overlaps partly with other adaptation strategies such as community-based adaptation and cross-sectoral approaches such as integrated watershed or coastal zone management. Compared to infrastructure- or technology-based adaptation, people adapt by improving the state of ecosystem services as well as better management of biodiversity and ecosystems. Therefore, vulnerability is reduced and people’s adaptive capacitytowards the negative impact of climate change increases. In this context EbA is very similar to ecosystem-based disaster risk reduction (Eco-DRR) by using natural solutions and participatory, locally accepted approaches for reducing current and future risks to people.
In practice, EbA measures are often combined with “grey” infrastructure (e.g. coastal protection via sustainable mangrove coral reef management and dyke construction to reduce storm risks or watershed protection in combination with water reservoirs and irrigation canals to buffer drought or flood events).
Apart from the intended outcomes, EbA measures tend to generate additional co-benefits such as carbon sequestration or biodiversity conservation, improved livelihood conditions and thus are often considered as no-regret options. To determine the specific requirements of maintaining or restoring an ecosystem and its services, EbA ideally draws on a combination of local knowledge and studies of climate change impacts or integrated climate analyses, which make use of climate scenarios and models.
Worldwide surveys have shown that restoration and conservation of ecosystems are generally cost effective. In comparison to the economic loss caused by loss of ecosystem services, the cost-benefit ratio of return of investment of appropriate restoration of ecosystems may be as high as 3 to 75, depending on the ecosystem context and the measures taken (UNEP 2010, 6).
For example, a study in Vietnam indicates that mangrove rehabilitation at village level is generating significantly higher wealth benefits from risk reduction and natural resource utilization and (2.3 million USD over 20 years) compared to dyke construction (only 0.5 million USD) (Köhler, M.; Michaelowa, A. 2013). Cost-benefit analysis aplied under the UNEP-IUCN-UNDP Mountain EbA Programme in Peru indicate a significant higher revenue (a net present value of 841,902 USD over 20 years) under an EbA scenario, including the low impact grassland management in a community with wild lamas, compared to a business as usual scenario (NPV of 486,571 USD over 20 years) with intensive domestic cattle management (Rossing, T; et al 2015).
EbA can be integrated into adaptation projects by regarding certain elements at each stage of the adaptation project cycle. The following figure shows which elements of EbA should be taken into account and the respective type of tools, methods and approaches that can be utilized at each step.
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).
When assessing vulnerabilities, the inter-linkages of ecosystems to economic and social systems should be taken into account. A vulnerability analysis, containing climate impact assessment, analysis and household surveys, adjusted to regard those inter-linkages can be used.
The identification and selection of suitable EbA measures can be based on vulnerability, impact, feasibility and other criteria. Instruments that support this process are the DPSIR framework, climate impact chains and climate proofing for development as well as cost-benefit and multi-criteria analysis.
After adopting EbA specifics in the project’s strategy, the implementation follows the general course of action. Economic options, e.g. incentives, and methods for management and planning help to integrate and consolidate ecosystem-based measures.
The monitoring and evaluation should include indicators reflecting changes within the ecosystems concerned. The manual “Adaptation made to measure” assists with the design of an M&E system.