Posted on November 13, 2024
Mangroves deliver important eco-system services. They store carbon, protect coastal communities and are hotspots for biodiversity. But they are threatened by urban development, wood harvesting and shrimp aquaculture. In the Guayaquil access channel in Ecuador, maritime contractor Jan De Nul and its partners built their first ‘AquaForest’ mangrove island, using locally dredged material. They developed a blueprint for mangrove restoration worldwide.
Eco-system services
Mangrove forests are important carbon sinks and can retain up to four times more carbon per hectare than tropical forests. They serve as water filters, are hotspots for biodiversity, protect coasts from erosion and support socio-economic activities such as ecotourism and sustainable fishing activities. But since 1980, 50% of mangroves in Ecuador have disappeared due to intensive aquaculture activities, wood harvesting, and urban development.
Circular use of dredged material
The 50-hectare AquaForest mangrove island is located at an existing tidal flat area in the Guayas river delta in Ecuador. It’s not the first mangrove restoration project, but it is the first to build a mangrove island from scratch using locally dredged material. The circular reuse of dredged material creates an important economic advantage, making this blueprint for mangrove restoration very interesting to reproduce on a large scale.
Dominic De Prins
Project manager for AquaForest in Ecuador at Jan De Nul Group
“In 2018, Jan De Nul Group signed a 25-year concession contract to undertake maintenance dredging in the access channel to the port of Guayaquil in Ecuador. Early in the project, we noticed a lot of shallow tidal flats near the access channel. We came up with the idea to elevate one of these areas by reusing dredged sediment from the access channel of Guayaquil, that would allow the development of mangrove habitats. This enables us to connect nature restoration to one of our key activities.”
Eco-engineering
The goal of AquaForest is to create a sustainable mangrove ecosystem that will become autonomous in the future. The first step was to establish conditions that are ideal for the growth of mangrove. To achieve this, the partners conducted an extensive feasibility study and applied targeted eco-engineering to the AquaForest site.
Together with local communities
Collaborating with local communities is a vital component of the project. AquaForest established a local management system for the mangrove island, building upon its ecological and socio-economic value. Local stakeholders and communities were involved in every step of the project and act as custodians, knowing their livelihoods largely depend on local fisheries.
Scale-up
In the next years, the AquaForest partners will test, monitor and quantify the efficiency of this newly created mangrove ecosystem. They will look at its qualities in protecting coastal communities against floods and erosion, in increasing biodiversity, and in supporting the development of socio-economic activities. This pilot project should pave the way for other similar projects in the region, as well as globally in other locations where mangrove forest can thrive.
Dominic De Prins, Jan De Nul Group:
“Jan De Nul has the expertise, equipment, management capacities and global anchorage to reproduce AquaForest both in the region and in other parts of the world. The circular use of dredged material adds an economic advantage, making this type of Nature-based-Solutions economically feasible. We truly believe this project has the potential for large-scale mangrove restoration worldwide.”
Andrea Reyes
Assistant Professor Biology, Escuela Superior Politécnica del Litoral (ESPOL)
“We have investigated several factors that are important for the optimal growth of mangrove habitats in AquaForest. The interaction with waves and currents, how water flows through and drains from the soil, the type of soil in which mangrove trees thrive, the interaction with other plants and species… We also looked at the type of protection which juvenile mangrove trees need during the first months of their development.”
AquaForest is an international project consortium coordinated by Jan De Nul. Partners include: South Pole, Mantis Consulting, Haedes, University ESPOL in Ecuador, University of Antwerp, Vrije Universiteit Brussel, and the NGO Fundación Calisur. We also involve local authorities, government, researchers, and local communities.
The project is subsidised the Flemish government via the Flanders International Climate Action Programme and by the International Union for Conservation of Nature (IUCN).
