More than half of all mangrove ecosystems at risk of collapse by 2050

Communities living along this receding shorelines of low-lying Vypin Island off India’s west coast understand the importance of healthy mangrove ecosystems.

Sea level rise and severe tidal floods have forced many families here to relocate to higher grounds, but they still try to plant trees on the shores of Vypin and the surrounding areas in the Kochi region of Kerala state.

Tidal flooding occurs when sea level rise combines with local factors to push water levels above the normal levels.

Mangroves can provide natural coastal defenses against sea level rise, tides and storm surges, but according to the International Union for the Conservation of Nature these ecosystems are under threat around the world.

This in southern India is among the critically endangered.

Other coastlines such as Salinas, Puerto Rico are also threatened by illegal building which results in the clearance and destruction of mangroves.

It's the first time the IUCN has created a "Red List" of endangered mangrove ecosystems.

It's researchers say more than half of all mangrove ecosystems at risk of collapse by 2050.

They assess almost a fifth of mangroves globally are classed as Endangered or Critically Endangered which means they are at risk of collapse.

Marcos Valderrabano, one of the lead researchers for the IUCN's Red List of Ecosystems, says sea level rise from climate change causes the greatest damage to mangroves.

He says: "This was the first time we conducted a global Red List of mangrove ecosystems that assess the risk of the ecosystems collapse globally and the surprising result was that 50% of the mangrove ecosystems of the world are threatened, are at risk of collapse. And the main reason for these is sea level rise, when we look at the models of sea level rise projection into the future, there is 30% of the mangrove ecosystems that are going to be affected by sea level rise in the future and they're going to have very low capacities to survive and recruit new plants as we move on."

Valderrabano believes as climate change increases the mangroves become an even more vital defence against coastal erosion.

That also means the destruction of fisheries, adding to the woes of coastal communities.

"Mangroves are very, very important ecosystems for coastal communities and we learned that a few years ago when we realized that when a very high tsunami arrived to the coast, coastal communities that have strong mangroves can defend much better against the these high and events, while others without mangroves are much more defenceless. As we started digging into the mangrove ecosystem services, we learned that they are essential providing fisheries nurseries and the fishing industry depends very much on the capacity of fish to reproduce in the mangrove area. And now that we are getting into the climate change, the importance of mangrove sequestrating carbon and restoring carbon under the roots in the soil, it's also essential," explains Valderrabano.