Mangroves are trees that grow mainly in tropical and subtropical regions near the Equator, typically along coastlines or rivers affected by tides. They live in hot, muddy, salty conditions that would be inhospitable for most plants. However, mangroves have adapted. Not only are they able to survive in challenging conditions, they actually thrive. The mangrove ecosystem is also an important habitat for a diverse range of species, and rivals rainforests as a highly productive region of diversity. Birds, reptiles, insects, molluscs, crustaceans and fish call mangroves their home.

Scientists have discovered that mangroves can capture and store very large amounts of carbon dioxide, and this has been highlighted in a 2020 UNESCO report. They are capable of soaking up around five times more CO2 from the atmosphere than the trees in the rainforest, and 70 times more than the trees in European forests.

Mangroves use the CO2 they capture to produce oxygen (O2) and carbon (C) through photosynthesis, releasing the first in the atmosphere and incorporating the latter in their leaves, branches, and roots. They grow in brackish water, which has a higher salinity than freshwater but not to the extent of seawater. Their leathery and salty leaves constantly fall in the brackish water, settle at the bottom, or are dragged down by crabs. Remains of plants, animals, and other organisms are brought into the mangrove forests by the tide. They are slowed down by the tree roots, leaving additional carbon-rich material behind. As the organic material is gradually covered by fine-grained sediments, the soil underneath becomes deprived of oxygen. The decomposition of all that organic material would usually release CO2 but the salty and oxygen-poor sediment considerably slows down the decay process. As a result, mangrove sediments can store organic carbon for a long time.

The roots of mangrove trees are partially growing in the air, and partially in the water. They spread out in a star shape in all directions, and make the trees appear to be standing on stilts above the water. This complex root system holds the mangrove upright and allows the trees to handle the daily rise and fall of tides. It creates a woven carpet which limits the passage for larger animals and fish. For humans it is also impossible to walk through it.

Thanks to their strong root system, mangrove forests break down the power of waves. They protect the coasts from big storms and even tsunamis, and they prevent erosion and the destruction of coral reefs by stopping overflowing sand and violent waves. They also absorb nutrients, stabilise reef salinity, filter and trap sediments, which in turn allows the nearby coral reefs to thrive. Besides being a nursery, shelter, and feeding ground to many different species, they increase fish populations and therefore provide fishermen with better income.

However, mangrove forests have been reduced to less than 25% of their natural extent, according to a report by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) published in 2019. Over the last 50 years, huge numbers of mangroves have been logged to make way for holiday resorts and shrimp farming. On a smaller scale, fishermen sometimes cut the mangroves to park their fishing boats. The IPCC Special Report on the Ocean and Cryosphere in a Changing Climate notes the reduction or even disappearance of these coastal ecosystems in certain areas. The report also points out that their crucial function as carbon sinks (sequestering carbon in the subsoil) would considerably help certain countries to achieve their national objectives in terms of net greenhouse gas emissions. 

More recently, new awareness on the importance of the mangrove in protecting our environment, as well as for the health and well-being of humans, is spurring protection and reforestation projects around the world. Sri Lanka, with its coasts heavily impacted by the 2004 Indian Ocean tsunami, became the first country to protect all of its mangrove forests. And Pakistan, India, Thailand, Madagascar, Tanzania and the Philippines are now actively reforesting their mangroves.

Together with the Mama Earth Foundation, we created the Malizia Mangrove Park in the Philippines where half the mangroves were lost over the past 100 years. Pujada Bay in Mati, where the park is located, has been declared a marine protected area in 1994 meaning the country’s mangroves are under nature protection. We also teamed up with the Davao Oriental State University and local community to plant new mangroves next to the existing ones. 

The Malizia Mangrove Park makes an important contribution to the restoration of this coastal ecosystem, provides a better income for local residents, and the mangroves bind large quantities of carbon dioxide. Thanks to donations and help from around the world, we reached our goal of planting one million mangroves and have now set the new goal of 2 million mangroves. Numbers aside, our aim is to restore the forest to a point where the mangroves can reproduce themselves and no further human help is needed. UPDATE: We have now surpassed the 2 million mangrove donation mark and are rapidly approaching the next half of a million which we hope to reach by the end of the Vendée Globe! Help out by making a mangrove subscription and effectively donating 1 mangrove a day! A mangrove a day keeps the carbon away!

The process of planting mangroves reminds of the one applied by the people from Instituto Terra we met during one of our The Ocean Race stopovers. Created by famous Brazilian photographer Sebastiao Salgado, the Instituto Terra restores the Atlantic Forest in order to bring back a thriving ecosystem on almost 700,000 hectares of land that had been destroyed by human activities. 

In Pujada Bay, mangrove seeds from various species are collected within ten kilometers of the Malizia Mangrove Park, so that only species native to the area are planted. These elongated seedlings are then grown in a nursery. Once three to five leaves have developed, they are about four to five months old and ready to leave the nursery and be planted in the park. 

Experts from the local university, led by Dr Lea Jimenez, decide which seedlings need to be planted and when, to make sure that the correct mangroves species are planted at the right time. People from the local community are hired and plant the small mangroves when the tide is low. Together, students and forest managers of the Mama Earth Foundation are overseeing the upbringing of seedlings in the nurseries and the planting operations. Over the following months and years, they monitor the growth and strengthening of the mangroves. These trees grow very fast and can live up to a hundred years!

We have also started a new scientific project in the park called Reviving Pujada Bay. Together with our partners Mama Earth Foundation, Zurich Group Germany and rrreefs, we are rebuilding coral reefs with 3D-printed clay bricks next to where we restore mangroves. Through an experimental approach, we want to investigate the potential benefits of simultaneous restoration of mangroves and coral reefs.

Whether it is preventing mangroves from being cut down, or actively planting seedlings, donating mangroves or even conducting a scientific project - every mangrove counts. Together, we can better protect and restore an incredible ecosystem, and we have to do it now - because this is A Race We Must Win.

This is a song created, sung and recorded by the Amihan Boys, a surfer and environmentally active community helping collect plastic from around the Malizia Mangrove park, that would otherwise smother the seedlings. They are also great supporters of Boris and Team Malizia and to show their support and give you a small idea of the projects they carry out, they wrote a song: