On the Indonesian island of Sumatra, mangroves are a source of life, natural resources and economic activity for local communities. Threatened by industrial palm oil production, intensive aquaculture and charcoal exports, this forest ecosystem between land and sea is disappearing. To restore the mangrove in North Sumatra and allow it to once again realise its wide range of environmental and socio-economic benefits, Reforest'Action is funding two regenerative projects that will have helped to reconstitute nearly 900 hectares of mangrove since 2017 and by 2024. Discover the report of our mission in the field, meeting our project leaders and the people who contribute to them on a daily basis.
The mangrove, a vital ecosystem for biodiversity and people
A unique forest ecosystem between land and sea
The mangrove is a plant formation that covers 75% of the coasts, deltas and estuaries of the intertropical regions. This forest ecosystem grows on the foreshore, the part of the coastline that is submerged during the highest tides and emerged during the lowest. Also known as the tidal balance areas, the foreshore is a specific biotope with relatively uniform physical and chemical characteristics, conducive to the development of the main mangrove trees. Nearly one hundred different species of mangrove trees have been identified in America, Africa and Asia. All of them have the ability to adapt to high salinity, root immersion and low soil oxygenation due to silt. For example, where Rhizophora have stems that anchor directly in the mud, Ceriops have emergent stilt-like roots arranged in arches that allow them to rise above the water level. In Avicennia, vertical stems, called pneumatophores, have small slits that open at low tide to allow respiration. But the mangrove is a complex and diverse ecosystem that grows in symbiosis with other plant species, such as noni or nipa palm in Sumatra. These trees thrive in the same conditions as the mangrove trees and enrich the mangrove ecosystem with a diversity of species essential to its balance.
Mangroves provide a wide variety of benefits
Mangroves are vital for biodiversity and local communities. Multifunctional by nature, it provides many ecosystem services, both environmental and socio-economic.
Thanks to the rapid growth of mangrove trees and the size of their biomass, mangroves are a carbon sink that can store up to ten times more CO2 per hectare than terrestrial forests. It thus sequesters about 10% of global carbon emissions, even though it represents only 1% of the surface area of tropical forests, and contributes directly to the mitigation of climate change.
Mangroves are a true ecological niche whose conditions and resources are absolutely necessary for the maintenance of the species it shelters. They are the habitat of numerous animal and plant organisms, whether terrestrial or underwater. Because it is an ecotone, in other words a transition zone between two ecosystems, it is particularly conducive to the creation of biological corridors, these environments that functionally link different habitats that are vital for a species. Thus, about 80% of marine animal species in the Indian Ocean find refuge in mangroves during a stage of their life. The mangrove root system serves as a spawning ground and nursery for hundreds of species of shrimp, crustaceans and fish.
The root system of the mangrove also gives it an essential role in the preservation of soil and water resources. Thanks to their roots, mangroves fix the unstable soils in which they grow, and therefore limit coastal erosion and sea level rise. They absorb some of the debris and organic pollutants, such as phosphorus and nitrogen, that are discharged into rivers or carried by ocean currents. They can even play a role in cleaning up domestic wastewater.
Thanks to its density, the mangrove constitutes a bulwark to protect territories against climatic hazards, and thus acts as a buffer zone by breaking the waves and attenuating the power of gusts. On 26 December 2004, an undersea earthquake occurred north of Sumatra and caused a tsunami that spread from South Asia to East Africa. In the aftermath of the disaster, studies conducted as part of the Third Asian Wetlands Symposium showed that coastlines with intact natural barriers, including mangroves, were less affected by the waves.
Rich in valuable resources such as fish, medicine, forestry, fruit and honey, mangroves are essential to local populations and their economic activities. It supports fishing and local trade, provides wood from its dead trees for heating and construction, fibres and ink for textiles, fruit and honey from its flowers and even medicinal remedies. The mangrove thus contributes to the livelihoods, health and security of coastal communities.
In Sumatra, the mangrove is disappearing due to anthropic pressure
Indonesia is the country most affected by deforestation in the world, with forests disappearing twice as fast as in the Amazon. The mangrove, in particular, is the forest ecosystem that is disappearing at the most alarming rate. While North Sumatra province had 200,000 hectares of mangroves in 1987, less than half of that remains today with only 83,000 hectares. In Aceh province, the mangroves were also severely degraded by the 2004 tsunami. Land use change and forest degradation are the main causes of mangrove loss in Sumatra. Mangrove forests tend to be replaced by oil palm monocultures or intensive aquaculture ponds, or are illegally cut down for charcoal production.
Palm oil, the vegetable oil extracted from the pulp of the oil palm fruit, is still widely used in processed food. Today, around 85% of the world's palm oil production comes from plantations in Indonesia and Malaysia. It is directly responsible for deforestation, since oil palm plantations are carried out at the expense of natural forest ecosystems, particularly mangroves on the Sumatran coast. Encouraged by the banks, which offer more attractive insurance for agricultural land with oil palms, villagers are planting more and more of them on Sumatra's coastlines, even though the tree is unsuited to the pH and salinity of the coastal soil and does not provide them with any additional income. As for the industrial companies seeking plots for oil palm plantations, they have techniques for adapting coastal soils to this crop, notably by creating freshwater canals in place of natural mangrove ecosystems.
In Sumatra, mangrove trees are also cut down to make way for intensive aquaculture ponds, especially for shrimp farming. These ponds are profitable for a few years, but then their productivity decreases and they are abandoned as they are. Other areas are then deforested a little further away. This practice is directly responsible for deforestation and also contributes to the pollution of groundwater, which becomes unusable because of the infiltration of salty and antibiotic-polluted water.
The production of charcoal from mangroves, mainly for export to Europe and Japan, is also the cause of illegal logging in these ecosystems, which are now protected by the Indonesian government.
Regenerative projects to restore Sumatra's mangroves
Reforest'Action's involvement in Indonesia dates back to 2017. With the aim of restoring and extending the native mangrove on the island of Sumatra in order to protect its coastline and secure the economic activities linked to it, a sustainable partnership was established that year with the local NGO Yagasu. Since the autumn of 2021, Reforest'Action has extended its range of activities by financing a second mangrove restoration project in Sumatra, designed to last three years and carried out by the NGO Yakopi.
Five years of action for mangroves alongside local actors
"In Sumatra, we work with two local actors," says Martín, coordinator of Reforest'Action's projects in Asia. "On the one hand, Yagasu, which is an NGO with over twenty years of experience in ecosystem restoration, livelihood improvement and local community integration. On the other hand, Yakopi is a newly established NGO with a young and highly motivated team. We selected these two projects in accordance with our specifications, not only because they are very qualitative programmes in terms of mangrove restoration and biodiversity preservation, but also because they both include a component dedicated to the economic development of the populations. These regenerative projects are thus conducive to the sustainable mobilisation of communities.
The restoration of mangrove ecosystems within the framework of our projects aims to restore and increase their ecological services, which are currently degraded and no longer contribute to the well-being of populations. In addition to mangrove planting, many activities are carried out in the field by Yagasu and Yakopi to enhance the environmental resources of the mangrove and generate income for local communities.
"A regenerative project aims, beyond the restoration of a given ecosystem, to enable this ecosystem to once again achieve its multifunctionality, i.e. the wide variety of environmental and socio-economic benefits it produces for local communities," continues Martín. "The mangrove restoration activities carried out in our projects in Sumatra are thus closely linked to the socio-economic activities of the people and enable them to achieve sustainability in terms of resource renewal and their livelihoods. Such projects therefore ensure the sustainability of the restored mangrove ecosystems as the people find a direct interest in their protection."
Since 2017, thanks to the support of Reforest'Action, Yagasu has restored 415 hectares of mangroves within the provinces of North Sumatra and Aceh. For its part, Yakopi, funded by Reforest'Action since 2021, aims to restore 481 hectares by 2024 in these same provinces. At the same time, the two organisations are increasing the number of awareness-raising workshops for local communities and developing various economic sectors that make use of the mangrove's natural resources, such as the production of batik and palm sugar, or the practice of silvo-fishery.
Local communities commit to rehabilitating the mangrove
In concrete terms, on the ground, the projects run by our local partners are based on the mobilisation of the populations. From the collection of propagules to their germination in bags, from the maintenance of plants in nurseries to their planting on the beaches and in the deltas - the villagers are full-fledged actors in the restoration of mangroves. Ismael, who we met on the riverbank in Seuneubok Peusangan, is spending his morning planting mangroves with Yakopi. "I joined the planting team with the hope that our mangrove will finally regenerate and become home to many species of fish. Around me, I try to share my motivation, so that more and more villagers get involved in the restoration." Alini, who welcomes us to the village of Rantopanjang, is involved in the nursery work for the Yagasu project. "I collect the propagules, place them in the bags and then take care of them for about three months. I receive a salary for this work and it helps me to increase my household income." Whether in terms of job creation or generating additional income through economic activities from the mangrove, 29 villages have benefited from the Yagasu-led project since 2017, and 8 villages from the Yakopi-led project since 2021.
Reforest'Action's expertise in the field to strengthen the implementation of projects
Because any ecosystem restoration project only makes sense if it is properly implemented and really delivers the expected benefits, Reforest'Action attaches paramount importance to monitoring and measuring the results and impacts of projects over time. "In the field, Reforest'Action's added value for our operational partners, such as Yagasu and Yakopi, is based on two pillars: monitoring and impact assessment," explains Martín. "Through audit missions, we monitor the activities carried out within the framework of the project and highlight areas for improvement. We also measure the concrete impacts of the project, particularly in terms of biodiversity development, carbon storage and economic benefits for local communities. To do this, we have Project Officers located around the world, specialising in forestry, who travel to the projects closest to them to carry out the audits. Here in Indonesia, our Project Officer is Ade. He is a bright and motivated young professional based near Jakarta, who did his first audit for Reforest'Action in Sumatra.
The audit mission conducted in Sumatra in October 2022 by Martín and Ade is thus an opportunity to observe, within a sample of plots, the growth of mangroves, their planting density, their survival rate, and other indicators that show how well the restoration projects are going, such as the presence of biodiversity. "The first trees planted in Sumatra in 2017 with Reforest'Action funding are now almost at a mature stage. They have recreated a full-fledged forest ecosystem, full of life and resources for the local communities, where there was nothing five years before," says Martín as he walks through these historic plots, where the mangrove has regained its rights. As far as the development of biodiversity is concerned, the evidence is indeed before our eyes: the restored plots are already teeming with animal life and our pirogues will come across the stealthy flight of the blue-backed kingfisher and the great white heron, the mincing of the very rare silver-leafed monkey, as well as the discreet swimming of numerous crabs, fish and jellyfish sheltered by the large stilt roots of the mangrove.
Through exchanges with the Yagasu and Yakopi teams, as well as with the villagers involved in the projects, Martín also assesses their sustainability, in order to ensure that the regenerated ecosystems are protected in the long term. "Another important aspect of these projects is the conservation of the restored mangroves. Without conservation actions, this restoration would not be sustainable." At the end of the audit, Martín and Ade will produce a report on the projects' achievements and areas for improvement to ensure the best possible implementation.
In Sumatra, villagers reconnect with the benefits of mangroves
Immersed in the heart of the black swampy landscape, carried by the river currents that flow to the Strait of Malacca, we went to meet those who live off the mangrove and who work together to restore it. On the ground, villagers are quick to share their testimonies with us. We gathered the stories of their greatest successes in rehabilitating the mangrove at the heart of their daily lives.
A village against oil palms
In the small green village of Pasar Rawa, under the canopy of a wooden pavilion recently built on the riverbank to host community activities, the villagers are rejoicing. Three years of struggle against illegal oil palm plantations on their land is finally coming to an end. In 2019, the palm oil company PT Sumber Hasil Prima broke into Pasar Rawa without official permission. In order to install oil palm trees, the company deforests 138 hectares of mangroves on village land overnight. Supported by our partner Yagasu, the community mobilised and warned the government. The government then called in the Indonesian forestry police to note the illegal occupation of the plots by the company and the deforestation of the mangroves that were originally located there. PT SHP was then forced to leave the site, leaving behind severely degraded land, which was returned to the villagers. Today, thanks to the support provided by Yagasu and the financing of Reforest'Action, the mangrove has regained its rights around Pasar Rawa. In this village of barely a thousand people, more than 300 are involved in the mangrove restoration project - a number that has been growing every year since 2019. Awarded the National Environment Award, the community was visited in 2021 by Eko Sri Haryanto and Dr. Sumarlan, both from the Ministry of Villages, Disadvantaged Area Development and Transmigration of the Republic of Indonesia, who came to personally congratulate the villagers for their struggle to restore the mangroves.
Mangroves in colour
The inhabitants of Pasar Rawa are now turning to the preservation of the mangroves that surround the village, and are integrating their natural resources into their daily lives. Accompanied by Yagasu, which provides materials and training, women's groups are learning how to produce batik, an ink made from mangrove branches to dye traditional local fabrics. Under the wooden pavilion by the river, we meet Hamidah, a batik trainer in the Pasar Gebang region. Leaning over a pewter vat in which the dark ink is simmering, she takes the time to explain her creative process. "We collect dead mangrove branches from the mangrove swamp and stew them in boiling water until a coloured liquid emerges. This ink, blue or brown depending on the type of tree, is then used to colour the patterns that we have first drawn and fixed with wax on fabrics. Then the colour has to be locked in with a fixing mechanism so that the batik dye does not fade over time." In Pasar Rawa and several surrounding villages, a real economic sector is now developing around batik, as Hamidah still testifies, proud that the fabrics are sold to passing customers.
Bees for the mangrove
Some 40 kilometers further north, the village of Lubuk Kertang also has a story of resilience in the heart of the mangrove. We are greeted by Zul, the village chief, and Ali, a beekeeper, who take us to a small, lush and cleverly landscaped garden. "When we were younger, the village was surrounded by mangroves and teeming with bees," they say. "But since 2006, almost all the forests have been converted to oil palm crops, and the bees have disappeared completely." Deeply disoriented by the loss of his childhood landscape, Zul decided to join the mangrove restoration project led by Yagasu in 2017. At the same time, he is thinking of a way to bring back the lost bees so that his community can benefit from their honey again. Using a dead mangrove stump, he creates the conditions for a beehive to establish itself, and plants a garden rich in plant biodiversity at the doorstep of his house. Ali, the beekeeper, then takes charge of collecting a queen from the nearby mangrove. The rest of the colony soon followed. Thus was born the first hive in Lubuk Kertang for more than fifteen years. For the time being, the honey produced comes from the flowers in Zul's garden, but the ambition is to transplant this floral treasure to the regenerated mangrove near the village. Because mangrove trees only bloom once or twice a year, depending on their species, the garden's flowers will allow the bees to remain sedentary and not go further afield to look for nectar, while pollinating the Avicennia and Rhizophora flowers when they appear, in February, June and October. "The mangrove is a source of life," says Zul, "but also of economic income for our communities." Today, the honey collected by Ali is sold in the small shops of Lubuk Kertang. Tomorrow, the village hopes that the bees can find a sustainable home in the heart of the mangrove.
The ocean has roots
The province of Aceh in northern Sumatra was hit hard by the 2004 tsunami. Here in Rantopanjang, villagers speak of the tsunami as an event that radically cut the timeline of their lives in two. "There was a before and after," says Mukhtar, a villager in his fifties who is involved in the reforestation project with Yagasu. "When I was younger, the mangrove forests around Rantopanjang were very dense and lush. But the tsunami devastated everything. The climate changed after the trees disappeared. The mangroves had a key role in cooling temperatures and preventing the beaches from eroding. Today, coastal abrasion is massive, and that's why I started planting mangroves." Since the tsunami, the local climate has indeed changed. The washed-out coastal mangroves were valuable for sequestering atmospheric carbon and maintaining the region's soils. Although their natural barrier acted as a protection for coastal villages, their destruction led to increased flooding events due to coastal erosion and increased rainfall. North Sumatra is now even more vulnerable to climatic hazards, especially during the wet season, which runs from October to April.
But, continues Mukhtar, another plague is responsible for the destruction of the mangroves that survived the tsunami: the proliferation, over the last ten years, of intensive aquaculture ponds. These artificial ponds, which replace natural mangrove forests, are a source of immediate income for the communities, but they are not sustainable. When their productivity decreases, they are abandoned as they are, and their antibiotic-laced water contaminates the entire surrounding ecosystem. "The mangroves, on the other hand, are a natural refuge for many species of crabs, molluscs, crustaceans and fish," explains Mukhtar. Thanks to the project financed by Reforest'Action, the villagers of Rantopanjang have become aware of the harmful impact of intensive ponds and are now committed to the reintroduction of the mangrove and the creation of organic silvo-fishery ponds that enhance the natural biodiversity of the mangrove. Convinced that such sustainable fishing practices will be more beneficial in the long term for the village's food security and local economy, Mukhtar is pleased: "Fish production has increased by 30% in three years thanks to the restoration of the mangrove. We have a lot to gain by protecting our forests. Putting roots back into the ocean - that is Mukhtar's plan to feed the community, and return the village to its former landscape.
The sweet sap of palm trees
Naturally present in the mangrove, in association with the different species of mangrove trees, the nipa palm holds a little-known resource that the inhabitants of the village of Abeuk Geulanteu have discovered thanks to the project led by our partner Yakopi. Traditionally, this palm tree, which is the only one of its kind that can grow in water, was used to create vegetable fibre roofs. But this practice required the complete cutting of the tree, thus contributing to deforestation in mangrove ecosystems. With the objective to conserve the integrity of the forests, Yakopi is thinking of a solution for local communities to continue to integrate nipa into their economy without cutting down the palm trees, which are valuable for maintaining the muddy soils that they help to fix with their roots. This is how the production of palm sugar, made from the sap of the nipa tree, is spreading in the villages associated with the project.
Each nipa stem is particularly prolific and can secrete up to one litre of sap per day. Where only the mangrove monkeys used to enjoy this precious nectar at dawn, before the villagers woke up, it is now the whole village of Abeuk Geulanteu that mobilises in its harvest. The process is simple and renewable: first, the fruit-bearing stem is shaken to condense the sap at its tip, then the fruit is harvested and the sap is collected from the branch using a small bag. The sap, which has a milky, coconut-like texture, can be consumed directly as an energy drink. It can also be cooked to extract a natural sugar, rich in minerals and with a particularly low glycaemic index, which is used for cooking or sold in local markets. The fruit is also consumed by the villagers and contributes to their food security. The product can be stored at room temperature for up to a year, and is now attracting consumers not only locally, but also increasingly abroad. Because the production of nipa sugar does not involve cutting the plant that produces it, it is a sustainable alternative to cane sugar production. Today, thanks to this economic sector, the villagers benefit from an additional income and the value of these trees has been multiplied - thus offering them the guarantee of their protection and that of the mangroves which shelter them.
Their future is called mangrove: protect, conserve, raise awareness
In order to ensure the sustainability of mangrove ecosystems in Sumatra, it is not enough to regenerate lost forests. It is also necessary to protect the restored and still existing ecosystems to prevent future deforestation. These conservation actions involve raising awareness among local communities who are best placed to preserve them.
Local mangrove conservation regulations
Recognising the lack of local regulation to discourage illegal logging in the mangrove, the authorities in the village of Sungai Pauh, located in Aceh province, turned to Yagasu to co-draft a regulation. Because the government's forest police do not have the means to deploy permanent surveillance at the local level, it is essential that each village has strict regulations to protect the mangrove. This text, the result of several years of work, came into force in October 2022, and has been brought to the attention of all villagers who must respect it, at risk of a fine and the obligation to finance the planting of 100 new mangrove trees for each tree cut. Now that such a mangrove conservation code exists in Sungai Pauh, the aim is to extend it to other villages in Aceh, so that forest conservation becomes the norm. At the same time, the village, which has benefited from a 73-hectare mangrove restoration programme funded by Reforest'Action, is being made aware by Yagasu of the economic benefits that mangroves can provide, apart from cutting down trees for charcoal production.
Village patrol in the mangrove
Founded by Yagasu, the Mangrove Patroll Team mobilises volunteer villagers to survey the mangroves and report any deforestation activities. "This all-volunteer patrol is essential to protect the mangroves in Sumatra and to ensure that both national and local laws are respected," explains Anton, who is in charge of the restoration programme run by Yagasu. With funding from Reforest'Action, the NGO provides training to villagers to involve them in mangrove monitoring to reduce deforestation. "The aim of the patrol is not, of course, to catch the wood thieves and take them to prison, but to report any logging activity in the mangroves so that the local authorities can punish the offenders." Beyond patrolling, mangrove conservation also, and above all, involves raising community awareness. By explaining to villagers that healthy mangrove ecosystems are naturally rich in fish and crabs, and can provide them with food without having to go fishing further out into the Strait of Malacca, Yagasu gives them a good reason to preserve these ecosystems. "We need to make communities aware of the importance of changing their habits," says Anton. "Cutting mangroves to turn wood into charcoal is still very common, but it directly affects the productivity of the fishery, because without mangroves there are no fish.
Generation Restoration: committing to the mangrove
This is why our partners are running awareness-raising workshops for schoolchildren and high school students, who will be the first sentinels of the mangrove tomorrow. In Paya Pasir, a small town near Medan, capital of North Sumatra province, a day-care centre has been set up on the riverbank to welcome the youngest children after school. Picked up by the storm at the end of the day, we take off our shoes to walk on the floor of the small wooden building, paced by cats. There, around low tables on which mangrove leaves are laid out, the children learn to recognise the different species of trees that make up the mangrove.
In Dogang, a few days later, an awareness-raising day on natural disaster prevention is organised for students of Al-Azhar High School in Medan. In addition to speeches by teachers and speakers from Yakopi and Reforest'Action, who explain the natural barrier qualities of mangroves against climatic hazards, a mangrove planting workshop is held. Barefoot on the slippery ground, the students learn to bury the long woody stems of the mangroves until they take root in the mud.
When we ask Rumini, a resident of Pasar Rawa since birth, if she thinks her children and grandchildren will protect the mangrove she helped restore, she says firmly: "Yes, it is an obligation. My family and the whole community of Pasar Rawa will continue to preserve the mangrove so that there will be forests all around our village again, like in my childhood. Our mother nature will be restored and it will be very beautiful to have these trees back. Our livelihoods will improve and we will finally be able to breathe freely. I wish my descendants to live in harmony with the mangrove, and to always be grateful to it."
We couldn't have wished for a better conclusion to our mission in the heart of Sumatra's regenerated mangrove.