1Long dismissed by westerners as sterile, mosquito-infested swamps, mangroves are now recognised as rich and fragile ecosystems; an increasing number of them are protected by international conventions, such as the Ramsar convention on wetlands.

2In spite of this political progress, between 1970 and 2000 the total surface area of mangroves shrank by a third, largely as a result of the explosion in the number of shrimp farms. Researchers eventually began to recognise the multitude of roles and functions played by these atypical ecosystems: they help to mitigate coastal erosion, protect against typhoons, purify water systems and provide vital breeding grounds for fish.

3Furthermore, mangroves are often inhabited by local populations who live off their resources, relying on the mangrove as a source of fish, firewood, tannins, salt, oysters and a place to grow rice. Entire civilisations have prospered in mangroves, reflecting the vast potential of these natural milieus which may be in constant movement, but are nonetheless rich in resources.

4However, these traditional practices are now under threat. Not from climate change directly, but rather by the societal response to climate change. In the interests of offsetting, carbon capture and reforestation, governments are allowing private companies to manage mangroves which have always been considered community property . These companies often plan a single, fast-growing variety of tree in order to achieve rapid results and publicise their efforts to bolster their green reputation.

5In Senegal, for example, vast swathes of Rhizophora have been planted by a Senegalese NGO, with financial backing from various international private and public-sector organisations, since 2006 in the Casamance region and since 2008 in the Saloum Delta. The results have been mixed, both in terms of the surface area actually planted and the capacity of these milieus to capture carbon and restore biodiversity. Not to mention the negative consequences for local women, who are no longer able to harvest oysters from the roots of the mangrove trees or shellfish from the replanted shoals.

••• Recent research has explored the shifting perceptions of mangroves over the ages, and highlighted some contemporary malpractices •••

6These replanting campaigns have in fact had a negative impact on local people, who find themselves shut out by fences and cut off from resources upon which they once depended. Researchers have already raised the alarm, urging politicians and resource managers to rethink their approach and make sure that the mangroves lose none of their rich diversity.