Mangrove Conservation as Nature-based Solution Program

Mangroves​​ are well-established nature-based solution for coastal hazards, in fact no less effective than engineering-based solutions. They are also among the most productive ecosystems, delivering goods and services such as habitat and nursery to fisheries, timber and plant products, sediment trap and water quality maintenance. But mangroves across the globe are fast vanishing.

In an effort to contribute in addressing this growing concern, GeoHazards International (GHI) launched its Mangrove Conservation as Nature-based Solutions program in 2023 in Calatagan, a coastal municipality in the province of Batangas, Philippines whose traditional economic base is fishing and farming.  Calatagan is surrounded by major seismotectonic structures and local faults. Thus, it is very prone to earthquake hazards, including tsunamis. It is also exposed to large waves during the southwest monsoon season and storm surges from typhoons. Calatagan has among the last mangrove stands in the Philippines, but they are under serious threat from coastal development, tourism, conversion to aquaculture, and pollution.

Piloted in Barangay Quilitisan, the program is now being implemented in two other barangays of Calatagan: Balitoc and Carretunan. The program aims to raise awareness on the protective role of mangroves and build local capacity for science-informed mangrove conservation and development. To achieve this, we adopt a participatory process combined with a quantitative approach. Specifically, we are empirically quantifying the capacity of mangroves in an area to attenuate waves based on mapping and data gathered by the people. Our experience shows that this greatly helps the people to not only understand their natural asset’s protective value but also to feel part of the process.

We also assess the conditions in the area that allow for or hinder mangrove development, in the process establishing baseline information and monitoring points, as well as training local people on the conduct of said assessment and systematic monitoring. The use of simple and locally available tools and methods ensures sustainability of the process, allowing the local people to conduct the assessment and monitoring even beyond the life of the project. Results of the assessment and monitoring inform effective ways to conserve and enhance the coastal ecosystem.