Mangrove Restoration: Nature-Based Disaster Risk Reduction

Green infrastructure, such as oyster reefs, provides equivalent or superior value to gray infrastructure (man-made structures like seawalls) at comparable costs; while both cost approximately $1 million per mile and offer similar storm protection, green infrastructure maintains or increases in value over time while gray infrastructure depreciates, and additionally provides multiple ecosystem services including water filtration, habitat creation for wildlife, beach nourishment, aquaculture opportunities, and tourism benefits.

Green infrastructure uses natural ecosystems like coastal dunes, tidal flats, and seagrass beds to protect coastal areas from natural disasters such as typhoons and storm surges, reducing wave energy by up to 60-70% while also providing additional benefits like carbon absorption and water purification; however, unlike gray infrastructure (artificial structures like seawalls and breakwaters), green infrastructure requires longer implementation times and careful site selection, and South Korea currently lacks comprehensive research and legal frameworks for its widespread adoption.

Gray infrastructure can be designed to resist or restrict coastal processes up to a specific design event, effectively detaching the project from ongoing processes except during that event. In contrast, nature-based designs require preserving or allowing coastal processes to continue largely unimpeded. Sediment or vegetation-based designs specifically need to work with existing natural systems rather than against them.

Conventional coastal defense using gray infrastructure (seawalls, breakwaters) constrains storm surge but amplifies effects inside protected areas, prevents sediment import, and causes subsidence. Green coastal defense allows wetland flooding, imports sediment, and creates long-term resilience through natural sediment trapping. The Netherlands' Sand Engine project demonstrates large-scale beach nourishment where massive sand deposits naturally distribute to dune systems over time, outperforming static seawalls that block sediment transport entirely.

Green infrastructure encompasses both natural and hybrid versions of coastal protection, including parks maintained by councils, dunes, beaches, wetlands, and potentially offshore features like kelp beds and oyster beds. This contrasts with grey infrastructure, which refers to man-made structures like sea walls and groins. Green infrastructure cumulatively provides multiple ecosystem services that benefit communities.

Three major international frameworks guide disaster risk reduction: Yokohama Strategy (1994), Hyogo Framework for Action (2005), and Sendai Framework (2015-2030). The Sendai Framework establishes four global targets: reducing mortality and economic losses, reducing disaster risk through prevention investment, enhancing international cooperation, and strengthening disaster preparedness. The framework aims to reduce disaster-related deaths to 100,000 or fewer and economic losses to 5% of global GDP by 2030. Effective disaster resilience requires early warning systems, response capacity, community participation, institutional training, and risk assessment working together.

The Sendai Framework for Disaster Risk Reduction 2015-2030 is a 15-year voluntary, non-binding international agreement adopted at the Third UN World Conference on Disaster Risk Reduction in Sendai, Japan, on March 18, 2015, and endorsed by the UN General Assembly on June 3, 2015. It establishes four priorities for action: understanding disaster risk through vulnerability assessment, strengthening disaster risk governance with clear strategies and institutions, investing in disaster risk reduction for resilience through public and private infrastructure investments, and enhancing disaster preparedness for effective response and 'Build Back Better' recovery. The framework contains seven specific targets: substantially reducing disaster mortality, affected people, economic losses relative to GDP, and damage to infrastructure, while increasing national disaster risk reduction strategies, international cooperation to developing countries, and access to early warning systems. The Sendai Framework supports the 17 Sustainable Development Goals and the Paris climate change agreement, recognizing that while states have primary responsibility for disaster risk reduction, all citizens must be engaged and risk-informed to achieve substantial reductions in disaster risk and losses in lives, livelihoods, health, and assets.

The Sendai Framework for Disaster Risk Reduction is a global agreement adopted by the United Nations in 2015 to guide disaster risk reduction efforts worldwide. It provides a framework for four key actions: (1) Understanding disaster risk - assessing and analyzing potential disasters and their impacts, (2) Strengthening disaster risk governance - improving policies and institutions for disaster management, (3) Investing in disaster risk reduction - allocating resources to reduce disaster risks, (4) Enhancing disaster preparedness for effective response - building capacity to respond effectively when disasters occur. This framework guides India's disaster management approach and international cooperation in disaster risk reduction.

The Sendai Framework for Disaster Risk Reduction (2015-2030) is a 15-year voluntary, non-binding global agreement adopted at the Third UN World Conference on Disaster Risk Reduction in Sendai, Japan, representing the first major post-2015 development agenda framework focused on disaster risk reduction; it builds upon earlier frameworks like the Yokohama Strategy (1994) and Hyogo Framework for Action (2005), establishing four priority areas (understanding disaster risk, strengthening disaster risk governance, investing in disaster risk reduction, and enhancing disaster preparedness) and seven specific measurable targets aimed at reducing disaster mortality, affected populations, economic losses, and protecting critical infrastructure, while promoting international cooperation and early warning systems.

The Sendai Framework for Disaster Risk Reduction 2015-2030 is a 15-year, voluntary, non-binding international agreement adopted at the Third UN World Conference on Disaster Risk Reduction in Sendai, Japan, on March 18, 2015, and endorsed by the UN General Assembly in June 2015. It establishes four priorities for action: understanding disaster risk through vulnerability assessment, strengthening disaster risk governance with clear strategies and institutions, investing in disaster risk reduction for resilience through public and private sector collaboration, and prioritizing disaster preparedness and building back better post-disaster. The framework outlines seven specific targets including substantially reducing global disaster mortality by 2030, decreasing affected populations, reducing economic losses relative to GDP, and increasing access to early warning systems. It represents a critical component of the post-2015 development agenda, supporting the 17 Sustainable Development Goals and climate change agreements, with the principle that while states bear primary responsibility, all citizens must be engaged and risk-informed to achieve substantial disaster risk reduction.

Co-management generally implies consultation with local users over resource use by state managers, becoming increasingly common in Canada since the 1970s. In Clayoquot Sound, co-management was implemented through the Central Regional Board with twelve members including two co-chairs (one First Nations, one provincial), five First Nations members, and five non-native local community members. Operating by consensus with double-majority voting giving First Nations effective veto power, this moved beyond consultative roles. The incorporation of traditional ecological knowledge became a cornerstone of improved environmental management, with critics arguing that positivist science applied from the top down failed to account for local knowledge. Ecotrust Canada advanced the conservation economy—an economy harvesting wealth from natural resources while meeting community needs and restoring natural and social capital, echoing the triple bottom line of profit, people, and planet. However, implementation failures persisted: by the 10th anniversary of the 1993 protest, organizers argued that Clayoquot Sound was not out of the woods yet, with vast sums spent convincing the public of preservation while scientific recommendations remained unimplemented.

Tribal sovereignty means individual freedom cannot be impaired by others, and tribes predating the United States have inherent rights to self-governance. Traditional Ecological Knowledge (TEK), accumulated over thousands of generations, is scientifically valid and complementary to Western science. The Salmon Core program (1995-2003) trained over 800 tribal youth in salmon restoration, demonstrating how intergenerational knowledge transfer creates lasting conservation capacity. Modern policy frameworks increasingly recognize tribal sovereignty: Secretarial Order 3404 mandates government-to-government consultation and cooperative agreements. While co-management faces legal resistance due to federal agencies' reluctance to cede authority, cooperative agreements achieve similar outcomes. The Umatilla Basin Project exemplifies successful collaboration: tribes and irrigators negotiated 'bucket-by-bucket' arrangements ensuring salmon habitat restoration while maintaining agricultural water needs, with salmon returning after being extinct for nearly 70 years.

Forest officer Tashi Thungun explains that conservation concepts are not new to the region, as ancestral traditions already included principles of environmental stewardship. The community believes forests, wildlife, and ecosystems are interconnected parts of their heritage requiring preservation for future generations. Effective conservation requires linking environmental protection with community livelihoods so people remain invested in protecting natural resources. The Thakn village council established community reserves covering 18 square kilometers of Thakn and 25 square kilometers of Suk land, to be jointly managed by the forest department and the tribe. This joint management model allows communities to retain ownership and decision-making authority while receiving technical and administrative support from government agencies, demonstrating successful integration of traditional ecological knowledge with modern conservation frameworks.

SEUS promotes sustainable resource use by indigenous people and local communities, weaving traditional ecological knowledge with modern science through new co-management forms. Taiwan established the Taiwan Partnership for the Satoyama Initiative (TIPSI) in 2015 as a nationwide network sharing successful SEUS experiences. Government agencies provide institutional support. Indigenous tribe experiences have encouraged other communities to develop innovative sustainable approaches to production and natural conservation, demonstrating how local initiatives inspire broader national adoption.

The acahual management model is fundamentally based on traditional ecological knowledge, which the presenter explains is the same as Western scientific method but approaches problems from opposite angles. Traditional ecological knowledge is based on methodologies for ecosystem management and conservation through practical experience and intuition developed by producers through daily observation over generations. The model is based on versatility because communities understand that ecological processes are not linear but have a vast range of alternatives. The model respects the vision of the environment because forests are biodiverse, and to avoid monocultures, communities must learn to understand and exploit regeneration capacities, species knowledge, and the producer's vision of where they want to lead their acahual.