How can ecosystem-based adaptation help societies to cope with climate change challenges? This paper contends that ecological stresses such as land degradation and decreases in biodiversity exacerbate the vulnerability of certain populations to the impact of climate change. Societies (particularly in developing countries) must invest in preserving and restoring local ecosystems to act as natural barriers against extreme weather events and climate conditions. Ecosystem-based approaches are low-cost, long-proven, and low-technology solutions to many anticipated climate change impacts. They can complement existing adaptation efforts, and better engage local communities in protecting their environments.
An essential component of adaptation is the protection and restoration of ecosystems and the habitats, natural resources, and services they provide. The multiple benefits of goods and services afforded by biodiversity and healthy ecosystems are largely unrecognised and unrecorded in natural accounting. Enhanced protection and management of natural ecosystems and more sustainable management of natural resources and agricultural crops can play a critical role in adaptation strategies.
Ecosystem-based adaptation complements other responses to climate change in two ways. First, natural ecosystems are resistant and resilient, and provide a full range of goods and ecosystem services, including natural resources such as water, timber, and fisheries essential for people’s livelihoods. Second, natural ecosystems provide proven and cost-effective protection against some of the threats that result from climate change. Specifically, ecosystem-based approaches can contribute to adaptation strategies by:
- Maintaining and restoring natural ecosystems and the goods and services they provide, such as water flows and water quality
- Maintaining coastal barriers and natural mechanisms of flood control and pollution reduction
- Reducing land and water degradation by actively preventing, and controlling, the spread of invasive alien species
- Managing habitats that maintain nursery, feeding, and breeding grounds for fisheries, wildlife, and other species on which human populations depend
- Providing reservoirs for wild relatives of crops so as to increase genetic diversity and resilience.
Investments in water resource infrastructure, especially dams for storage, flood control, or regulation, may be essential for economic development, enabling hydropower generation, food security and irrigation, industrial and urban water supply, and flood and drought mitigation. However, such engineered solutions to climate change may lead to loss of habitat or cause problems for downstream ecosystems and communities. Natural solutions may provide similar impact with less negative repercussions on the surrounding area. The protection and improved management of natural ecosystems can be integrated into infrastructure projects as part of sustainable development. Such projects have, for example, included forests as part of flood abatement, irrigation, and coastal defence measures. Further lessons are that:
- Within any given ecosystem, functionally diverse communities are more likely to be resilient to climate change and climate variability than biologically impoverished communities.
- Indigenous peoples have specialist knowledge in appropriate methods of conservation and can play a key role in mitigating and adapting to climate change. Ancestral territories often provide excellent examples of climate change-resistant landscape design. Indigenous peoples have cultivated plant species and animal breeds with a wider range of resistance to climatic and ecological variability. They have also developed resilient farming and water management strategies.
- Maintaining connectivity between natural habitats, and along altitudinal gradients, is important in enabling plant and animal species to adapt to climate change.
- Mosaics of interconnected terrestrial, freshwater, and marine multiple-use areas and protected reserves are better adapted than fragmented habitats to meet conservation and livelihood needs under changing climate conditions.
