Project overview

Yayasan Gajah Sumatra (Yagasu), an Indonesian NGO, has led community-based initiatives advancing biodiversity conservation, climate resilience and sustainable livelihoods across coastal Sumatra, Java and Sulawesi. The source materials frame the case against a wider blue finance gap: blue carbon ecosystems can store up to five times more carbon per acre than tropical rainforests, yet receive less than 1% of international climate finance. Yagasu's work shows how mangrove restoration can be structured as a durable investment model by combining carbon finance, philanthropic funding, technical assistance and community enterprise development.

Yagasu reports that it has conducted mangrove restoration since 2005, following the Aceh tsunami response, and has restored 16,400 hectares of degraded mangroves through grant mechanisms and carbon investment. Its ongoing blue carbon work includes 8,000 hectares of mangrove restoration in Sumatra, 5,300 hectares of mangrove restoration in Java, and 25,000 hectares of mangrove carbon conservation in North Sumatra and Aceh. The projects aim to form a Coastal Carbon Corridor connecting mangroves, associated mangroves, seagrass and coral reef ecosystems.

Approach

Yagasu's model is built on layered finance and community-based implementation. Rather than relying on one funding stream, it combines carbon investment, philanthropic grants, technical assistance and income from sustainable coastal enterprises. The approach starts with land and social assessment, public engagement, education and awareness, community capacity building, nursery work, tree planting, ecosystem conservation, monitoring, research and development, socio-economic support, and project management.

A key feature is the use of carbon standards and long-term carbon revenue. Yagasu combines carbon credit certification with Climate, Community and Biodiversity, SDG and biodiversity-related impact measurement. Its first carbon certification was the Yagasu-Livelihoods Mangrove Project in Sumatra, an 8,750-hectare project certified by Verra in 2015. The Yagasu-VNV mangrove carbon project, covering 8,000 hectares, was validated by Gold Standard in 2025, while the Yagasu-Apolownia mangrove carbon project of 3,300 hectares is expected by Yagasu to be listed with Verra in 2025.

The investment model described in the source materials combines pre-financing and carbon credit offtake agreements over a 30-year crediting period. Technical assistance grants support adaptation work, women's empowerment programmes, consultants and training for local villagers in mangrove tree planting and sustainable farming systems. Yagasu also works with universities and research institutes on project design, financial modelling, carbon accounting and marketing of green products. Village governments and landowners are engaged through agreements to support long-term carbon and biodiversity conservation.

Business and economic value

The business value of the Yagasu model lies in making blue carbon restoration more investable without separating climate outcomes from local livelihoods. Carbon credit revenues can create a long-term revenue base linked to verified climate outcomes, while grants and technical assistance help cover early-stage adaptation, capacity building and social inclusion costs. This can reduce implementation risk and create cash flows that are more aligned with the expectations of private capital providers.

Yagasu also strengthens project economics by developing complementary income streams from mangrove and coastal by-products. These include seafood production such as fish, crab, shrimp and oysters, as well as mangrove foods and beverages, honey, organic batik, household enterprises led by women, and mangrove ecotourism. The source materials report that sales from mangrove by-products increased family revenues by 49% over four years and that the overall male/female ratio of beneficiaries is 40/60.

The model also generates resilience and ecosystem value. It is designed to support greenhouse gas emission reductions, improve community resilience to climate impacts, prevent natural disasters, conserve biodiversity and develop green livelihoods. Reported targeted impacts include 3-4 million tonnes of CO2e over 30 years from 3,200 hectares of mangrove restoration, reduced flood and coastal erosion risks, and protection of species including invertebrates, birds and fish. For ACT Ocean, Yagasu offers a practical example of how carbon finance can be layered with community enterprise development to scale blue carbon restoration while creating tangible local benefits.

References

1. GHG Emission Reductions - Yagasu

2. Turning the Tide: A Financier's Guide to Investing in Blue Carbon Ecosystems - World Economic Forum