As Africa seeks to develop its blue economy, one of the standout opportunities is in the area of "blue carbon". Blue carbon project developers offer carbon credits to companies, in return for protecting or restoring coastal ecosystems, such as mangrove forests. While blue carbon is a small niche of the wider carbon market, it is in high demand for a simple reason: mangroves, along with sea-grasses and salt marshes, are extraordinarily effective as carbon sinks.
Mangroves have very deep and dense roots. This helps to trap sediment and prevent organic material releasing carbon into the atmosphere as it decomposes. In fact, mangroves can sequester carbon at a rate ten times greater than a mature tropical forest. Mangrove forests also provide a habitat where young fish shelter and they offer protection against coastal flooding and erosion.
But mangroves are in trouble, both in Africa and around the world. A July study by Diankai Wang of East China Normal University and colleagues, for example, found that the Niger Delta lost more than a quarter of its mangroves between 1988 and 2023.
