Author : Serrano, Shirly C.

Summary : The Philippines being an archipelagic country has one of the most diverse coastal ecosystems. Its mangrove ecosystems cater to 65 species of mangroves. Despite having these natural barriers, its coastal areas had a very high risk of climate change-induced sea level rise. This study was conducted to determine the status of the mangrove ecosystem; assessed the vulnerability to sea level rise; and document adaptation and mitigation activities in the coastal communities in the central part of Zambales, Philippines. The diversity of mangroves was assessed using a random quadrat sampling method in the twelve pre-selected stations. Each quadrat measures 10 x 12 meters and the quantitative description of each plant species was determined for diversity assessment. A total of 15 mangrove species surveyed in the area, under seven families where family Rhizophoraceae is the most represented family with six species and families Euphorbiaceae, Meliaceae, and Myrsinaceae are only represented with one species each. Shannon's Diversity Index showed that the mangrove ecosystems in Botolan had very low diversity (SDI = 1.71) and Iba had low diversity (SDI = 2.11). Agri­aqua development and encroachment served as the driving forces in the diversity of mangroves in the area. Other threats include solid waste disposal, quarrying, oil spill, organic fertilizer run-off, and soil erosion among others. These may threaten species and could eventually cause biodiversity loss, social conflict and economic loss. Results showed that vulnerability levels to sea level rise in the coastal barangays in the Municipality of Iba had moderate to high while the Municipality of Botolan had high to very high. Limited areas of natural protectors such as mangrove, seagrass, and coral reef ecosystems are one of the key elements to its high vulnerability levels. Concerted efforts of the local government units and the residents play a vital role to mitigate impacts of climate change these include regular mangrove tree planting, coastal clean-up drives, and strict implementation of environmental policies. Due to the importance of the mangrove ecosystems, preservation, conservation, and restoration be prioritized. While there are many tools used in vulnerability assessment, a simpler yet reliable is recommended as an appropriate for barangay levels.