Indonesia: Mangroves can play big role in tackling climate change

NEO CHAI CHIN Today Online 31 Jul 15;

SINGAPORE — Indonesia’s mangroves store large amounts of carbon, and saving them could help the country reduce greenhouse gas emissions, a new research paper has found.

Indonesia has lost an estimated 40 per cent of mangrove cover in the last three decades, but still has 2.9 million hectares of mangroves, more than any other country in the world. The mangroves store about 3.14 billion tonnes of carbon, equivalent to about one-third of the carbon stored in the world’s coastal ecosystems, according to the paper co-authored by scientists at the Center for International Forestry Research (CIFOR).

Indonesian mangrove loss contributed 42 per cent of global annual emissions from the destruction of coastal ecosystems, including marshes, mangroves and sea grasses, the scientists estimated. Emissions from the global destruction of coastal ecosystems were equivalent to 3 to 19 per cent of emissions from global deforestation.

Halting the deforestation of Indonesia’s mangroves could cut emissions that are equivalent to 10 to 31 per cent of its emissions from land-use, including agriculture and forestry, said the scientists.

Mangrove conservation should thus be among the strategies to mitigate climate change, they said in the paper, published this week in the Nature Climate Change journal.

Mangroves have been found to store three to five times as much carbon as the same area of rainforest. They are significant carbon sinks because of high rates of tree and plant growth, as well as slow decomposition due to anaerobic, waterlogged soil. Besides storing carbon, they also help in soil formation, nutrient cycling and wood production, and serve as fish spawning grounds. Aquaculture development is the main cause of mangrove loss in Indonesia.

The scientists measured carbon stocks of 39 mangroves at eight sites, and found the lowest values for plots in Cilacap in Java, and the highest for plots in Bintuni, West Papua.

“We hope that these numbers help policymakers see mangroves as a huge opportunity for climate change mitigation,” says Mr Daniel Murdiyarso, principal scientist at CIFOR and lead author of the paper.

“But to make progress, it is crucial that mangroves are protected and managed sustainably.”

The study comes as another Asian country recently became the first in the world to comprehensively protect its mangrove forests.

In a Sri Lankan scheme announced in May, hundreds of coastal communities will help protect existing mangroves and plant new ones in nurseries in coastal lagoons.

Backed by the Sri Lankan government, and with funding from US non-governmental organisation Seacology, the communities will get small loans and training to help them set up small businesses in return.