Could sustainable logging save Indonesia’s mangroves?

As long as you don’t convert them, they’ll come back.
Center for International Forestry Research (CIFOR) researcher Sigit Deni Sasmito measures the diameter of mangrove trees in a study on above-ground and below-ground biomass in mangrove ecosystems, part of Sustainable Wetlands Adaptation and Mitigation Program (SWAMP). Kubu Raya, West Kalimantan, Indonesia. Photo by Kate Evans/CIFOR

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It sounds counter-intuitive.

Indonesia’s vast mangrove forests, CIFOR has recently discovered, are a valuable carbon sink. They shelter unique species, protect coastlines from stormy seas – and they are fast disappearing.

Conservationists would see them protected from the logger’s chainsaw.

But it’s possible that selective and sustainable logging of these forests can be done while retaining much of their carbon – and save them from worse fates.

“The threat to mangrove forests is not the cutting of the above ground wood, but conversion to other uses,” says Muljadi Tantra, the Deputy Managing Director and Chief Financial Officer of a group of companies that harvest mangrove wood for charcoal and paper pulp in the provinces of Kalimantan and Papua.

“Once you convert it into a shrimp pond, the whole soil changes, and all the carbon is lost.”

“Whereas logging, if you do it right, and you only take a very small portion of the forest each year, the impact to the environment is very minimal, because of the ability of the mangrove to regenerate itself.”

“As long as you don’t convert them, they’ll come back.”

To test these claims scientifically, Tantra has given researchers from the Centre for International Forestry Research (CIFOR) and Indonesia’s Forestry Research and Development Agency (FORDA) access to his PT Kandelia Alam concession in Kubu Raya, West Kalimantan province.

Daniel Murdiyarso, a senior CIFOR climate change scientist and mangrove expert, will be leading efforts to measure the amount of carbon stored and the impact on those stocks of different ways of managing the forests.

“Our current research suggests that logging removes around 20 – 25 percent of the carbon stored in the ecosystem, while the majority of it remains under the ground, in the soil,” Murdiyarso says.

Logging, if you do it right…has a minimal impact to the environment because of the ability of the mangrove to regenerate itself. As long as you don’t convert them, they’ll come back.

But a cautious approach is needed, as well as more research, he says.

“Indonesia has around 3 million hectares of mangrove forests – but they vary in stages and status,” Murdiyarso says. “Some of them are very productive, and yes, they can be exploited – but not the way they were in the past, the way the terrestrial forests have been exploited. It has to be done differently – and very carefully.”

Tantra, meanwhile, believes the research – and his company’s transparency – may yield insights into how best to sustainably manage the forests. And that, in turn, he hopes, could change public perceptions of mangrove logging.

Family business

You could say mangroves are in Tantra’s blood.

A Chinese-Indonesian from Sumatra, his father started the company in the 1970s, selling mangrove wood for the paper pulp business. Before that, in the 1940s, his maternal grandfather was using mangroves for charcoal production and firewood.

These days, the company owns two concessions in Kalimantan and a much larger one in West Papua – 140,000 hectares of mangrove forest in all.

The company aims to harvest up to three percent of each concession each year, returning to each area after at least 20 years.

The wood is exported for charcoal and wood chip, although Tantra says the company recently lost a big buyer: Japanese companies, which used to prize the high-quality charcoal mangrove produces, have largely stopped importing Indonesian mangrove wood because of environmental concerns, he says.

This misses the point entirely, Tantra says.

“Sustainability comes from three things. Social impact, environmental impact, and economic impact – and the three circles have to work, in order to make forests sustainable. If the economic circle is missing, it’s not sustainable.”

He says that if the market for mangrove wood crashes, because of global concern about its sustainability, ironically, this could have a much more negative impact on mangrove ecosystems.

“Indonesia is not a rich country, so lot of people for their livelihood will depend on natural resources, and if the resource is not valued, they will look for other ways to make the area valuable: converting it to shrimp aquaculture, or rice field or oil palm plantations, which they hope will yield more money.”

“If we have to shut down our concessions, eventually they will be converted for other uses,” he says.

“But if we can actually extract more value out of the mangrove forest, including its environmental values such as carbon and things like that, there are many ways to justify keeping it as a mangrove forest.”

For this reason, Tantra is interested in the potential of schemes like REDD+ (Reducing Emissions from Deforestation and Forest Degradation), that aim to reward countries for keeping forests standing – and he is currently in the process of applying for certification by the Forest Stewardship Council (FSC).

The certification would assure customers that the company’s concessions are responsibly and sustainably managed – and if it happens, the company would be the first mangrove logging operation to achieve FSC certification, Tantra says.

“We’re gambling with this at the moment.”

“But what we hope the outside world can recognise is that by gaining this certification, they recognise we are doing it the correct way,” he says.

“I think it’s the right thing to do.”

One size doesn’t fit all

But what does sustainable harvesting mean in practice?

Currently, when PT Kandelia Alam harvests wood from an area of mangrove forest, they log the majority of the trees, leaving 40 trees per hectare to provide seeds for the next generation, Tantra says. Once the new growth springs up, the company monitors any gaps, and fills them by planting seedlings grown in the company nursery.

In 20 years, the theory goes, those trees will be mature and ready to be harvested again.

All this is according to Indonesian government regulation – but it’s these rules and regulations, according to Tantra, that are actually inhibiting companies from making their operations more sustainable.

Regulations governing Indonesia’s mangrove concessions need to be revisited – they are currently exactly the same as those for terrestrial forests.

“This ecosystem is very unique, and what’s been applied in terrestrial or inland forests is completely different to what’s happening here,” he said.

“There are many different experiments being done – in Malaysia, as well as what we have done ourselves in the past, that basically tell us there are other ways to make it more productive while having a smaller incremental impact to the environment and to the overall forest.”

This includes practices such as thinning out the largest trees across a wider area, he says, currently not allowed under the law.

“One of our biggest challenges is the inflexibility of the government regulation at this time. We need to lead by principle rather than rules and regulations.”

“I think if the government allowed us to more freedom, it would be better for us and better for the forest because we could adapt and optimise the way we do things – and they could just take our license if they see us doing bad things.”

But Daniel Murdiyarso believes government has an important role to play in regulating the sector.

“Government should provide informed guidance. Freedom can mean different thing to different individuals or companies.”

And, he says, revoking concession licenses is not a simple process legally, and would require verification from third parties – a labour-intensive process to carry out for every Indonesian concession.

He agrees, however, that the regulations governing Indonesia’s mangrove concessions need to be revisited – they are currently exactly the same as those for terrestrial forests.

“This ecosystem is very unique, and what’s been applied in terrestrial or inland forests is completely different to what’s happening here,” he said.

“The management plans and requirements for mangrove logging should not be the same as terrestrial forests – and they should be based on research,” he said.

Mangroves produce huge quantities of leaves, which when they fall, turn into organic litter, storing carbon in the soil. Upland forests, on the other hand, store the majority of their carbon in their wood – which means when they are logged, almost all the stored carbon is lost.

It’s possible, then, that mangroves could be logged more intensively than other forests while still retaining significant amounts of carbon in the soil – however, this needs to be tested scientifically, said Murdiyarso.

“Until we know exactly how logging mangrove forests affects the ecosystem carbon and related ecosystem services, we need to be careful,” he said.

Tantra, meanwhile, says his company offered up the concession site for research because he wants answers – for both commercial as well as ethical reasons.

“If you do it sustainably, that means it’s a perpetual income, for us, for the people surrounding the forest, and for the country,” he said.

“But if we do it the unsustainable way, you only get a one time income, the forest is ruined, and it’s not even economically justifiable if you don’t do it sustainably.”

“If you’re short sighted, that’s where you run into trouble.”

This work is part of the CGIAR Research Program on Forests, Trees and Agroforestry and is supported by USAID. 

For more information about CIFOR’s wetlands research visit:

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