08 Jun 2020 Story Ecosystems and Biodiversity

Three habitats that nourish our oceans

Photo by R9 Studios FL

World Oceans Day on June 8 celebrates the underwater world whose abundant marine resources sustain the land above it. Some of these resources and ecosystems, such as the overlooked seagrass, mighty mangroves, and colourful corals offer potent, nature-based solutions to climate change and sustainable development.

Seagrasses, for example, are found in shallow waters in 159 countries on all continents except Antarctica. They purify ocean water, provide fish nurseries, and support rich biodiversity. Seagrass sediment is one of the planet’s most efficient stores of carbon, according to the Out of the Blue: The Value of Seagrasses to the Environment and to People report launched on June 8 by the United Nations Environment Programme (UNEP).

The first-of-its-kind report describes seagrasses as the ‘lungs’ and ‘ecosystem engineers’ of the sea. It discusses the value of seagrass and makes recommendations on how to protect and manage the habitat. A single acre of seagrass may support as many as 40,000 fish, and 50 million small invertebrates like crabs, oysters, and mussels. Seagrass meadows support 20% of the world’s major fisheries and provide vital nutrition for close to 3 billion people.

“It is time to boost the profile of this underappreciated marine ecosystem and shine a spotlight on the many ways that seagrasses can help us solve our biggest environmental challenges,” said Ronald Jumeau, the Permanent Representative to the United Nations and Ambassador for Climate Change, Republic of Seychelles.

However, coastal development and population growth, rising pollution and climate change are threatening marine ecosystems. These threats are evident in the Gulf of Mexico, the Caribbean Sea and North Brazil Shelf. Not only do they  affect the seagrass meadows, but also coral reefs and mangrove forests that are characteristic of coastal ecosystems in the wider Caribbean shows the report: The State of Nearshore Marine Habitats in the Wider Caribbean.

Nature-based climate solutions

The habitats act together to trap and store carbon: seagrasses support mangrove function by protecting them from waves and mangroves protect seagrass beds from excess nutrients and sediment.

“The coral reef-mangrove-seagrass complex has been described as one of the most biologically diverse and productive systems in the world, with strong inter-linkages between the three,” said Ileana Lopez-Galvez, UNEP Programme Officer at the Cartagena Convention Secretariat.

Collectively, the ecosystems provide benefits to adjacent coastal communities and countries.

Take the Caribbean region—stretching from the USA in the north to Brazil and the Guianas in the south— for instance. A 2016 World Bank study monetized the economic value of the Caribbean Sea to the region at US$407 billion per year, of which US$54.55 billion can be directly linked to coastal and marine ecosystems. The sea supports economic activities like fishing, transport, trade, tourism, mining, waste disposal, energy, carbon sequestration and drug development.

In many Caribbean countries, most of the population, infrastructure, and economic activities are in the coastal zone.

“This places great pressure on coastal ecosystems. Damage from human activities has compromised the abilities of natural systems to withstand stresses from other sources such as diseases, alien invasive species, intense weather events, and climate change,” according to The State of the Nearshore Marine Habitats Report.

Restoration initiatives

Protecting marine ecosystems in the Caribbean is vital to safeguarding the future of countries and territories in the region.

One tool that can help is the Regional Strategy and Action Plan (RSAP) for the Valuation, Protection and/or Restoration of Key Marine Habitats in the Wider Caribbean 2021 – 2030. The RSAP aims to strengthen national and collective action by Member States to manage coastal ecosystems, particularly coral reefs, mangroves and seagrasses, to maintain the integrity of the habitats and ensure continued flow of ecosystem goods and services.

Efforts are also underway to protect seagrasses, mangroves and coral reefs in areas beyond the Caribbean. UNEP and its partners recently launched a manual for community seagrass projects, which provides guidance on how to run a community-based seagrass conservation project. 

The Ocean Foundation is developing a portfolio of new climate resilience-focused projects that bridge key gaps between science, policy, and on-the-ground intervention activities. Another notable mention is the GEF Blue Forests Project, which is a global initiative focused on harnessing the values associated with coastal carbon and ecosystem services to achieve improved ecosystem management.

The measures to protect the interlinked ecosystems speak to this year’s World Ocean Day theme: innovation for a sustainable ocean. They also highlight the UN Decade on Ecosystem Restoration (2021-2030) geared towards the restoration of degraded and destroyed ecosystems to fight the climate crisis and enhance food security, water supply and biodiversity.