Dutch Minister of Infrastructure and Environment Schultz van Haegen visited a large-scale mangrove restoration project in Indonesia. The coastal zone in the district of Demak in the north of Central Java is threatened by severe erosion. Because of this, the area is vulnerable to flooding. Dutch and Indonesian public and private partners, among which Wageningen University & Research, and the local population, have been collaborating since 2012 through Building with Nature to restore the mangroves and the local economy.
Severe erosion occurs because the number of mangrove forests along the coastline has drastically declined. The mangrove roots hold the soil so the ground does not erode; but, the mangrove forests have been cut down. Scientists of Wageningen Marine Research participate in research into how the mangroves can be restored in the most natural way possible. By building low, permeable dams made of poles and branches (such as formerly used for land reclamation in the Wadden Sea) in shallow water, the force waves are dampened. In calm water, the sediment (soil) is deposited and builds back up so that mangroves get a new opportunity to re-establish themselves along the coast.
In addition to the prevention of erosion, there also are economic opportunities to be realized through the restoration of mangrove forests. By restoring the mangroves that serve as important nurseries for fish, the local fisheries sector will be able to recover, there will be new possibilities for ecotourism, and the mangrove forest will again provide many traditional natural products. So, next to the sustainable solutions for coastal protection through Building with Nature, there will be plenty of sustainable sources of income for the local community, which will serve as vialble alternatives to the destruction of mangroves for economic gain.
Collaboration for sustainable solutions
In Demak, Wageningen University & Research collaborates with Wetlands International and Ecoshape, the Indonesian government, Witteveen + Bos, Deltares, UNESCO-IHE and Blue Forests, with support from Diponegoro University and local communities. The Dutch partners are all members of the Ecoshape platform: a partnership between contractors, engineers, knowledge institutes, governments and NGOs that aims for sustainable solutions in water engineering, by harnessing nature 's own resilience.
“Mangrove deforestation by mankind, along tropical shores worldwide, is far too extensive to think that we can restore these systems by the manual planting of only a few species, one tree at a time,” according to Dolfi Debrot, researcher of Wageningen Marine Research. “Fortunately, experience teaches us that mangroves are quite resilient. The challenge for us lies in finding out which minimal conditions and measures are required, so the restoration takes place primarily based on natural resilience. To prevent mangrove forests from being cut down again after restoration, it is essential to develop new ways of income generation that do not depend on the cutting of mangroves. That’s also a focus of our consortium.”
Building with Nature
Along with minister Schultz van Haegen, Prime Minister Rutte, minister Ploumen and state secretary Dijksma also traveled to Indonesia, together with managers of over 110 companies. A staggering 54 of these companies are from the Dutch Water and Maritime sector. Building with Nature has been a central theme during this trade mission, because the Dutch water sector especially aims for an integral and sustainable approach to coastal and water management.
The Building with Nature approach takes the ecosystem as a point of departure, which leads to more sustainable solutions, sometimes combined with human intervention, such as the restoration of water passages, sediment suppletion or the construction of soft engineering structures. Nature, in these solutions, is not just part of the design, but also profits by them.