Towards Establishing Coastal Greenbelts for Disaster Risk Reduction and Mitigation

Abstract

Mangrove ecosystems provide essential goods and services, with storm protection being their most valuable contribution at an estimated US$8,966‒10,821 per hectare. In the Philippines, the need for this coastal defense is urgent due to intense storms, such as the 2013 super Typhoon Haiyan, which have caused thousands of fatalities and billions of dollars in infrastructure and agricultural damage. Unfortunately, historical mangrove cover in the country drastically declined from approximately 450,000 hectares to just 120,000 hectares by 1994–1995, largely due to the conversion of these areas into aquaculture ponds. Scientific reviews demonstrate that establishing a 100-meter-wide vegetation buffer can effectively reduce wind and swell wave heights by 13% to 60%. While national mandates like the Coastal Greenbelt Bill remain pending in Congress, local government units and national agencies are leading the charge to legislate and establish these protective coastal greenbelts. Successful greenbelt establishment requires comprehensive and varied strategies, including the integration of beach forests in areas where mangroves cannot naturally grow. A critical component of this effort is reverting abandoned fishponds back to mangroves—as demonstrated by the Leganes Integrated Katunggan Ecopark—which is necessary to achieve an ecologically sustainable 4:1 mangrove-to-pond ratio. Furthermore, for severely eroded coastlines, Green-Gray Engineering interventions like rock-mound breakwaters are essential to restore the substrate elevation required for healthy mangrove growth.