SPATIO-TEMPORAL ANALYSIS OF DECADAL MANGROVE COVER AND FRAGMENTATION IN REGION IV-B MIMAROPA, PHILIPPINES
Keywords: Mangrove Extent, Fragmentation, Spatio-temporal analysis, Landscape metrics, GIS
Abstract. Mangroves are important vegetation that provides coastal protection and basic life necessities to humans and different marine organisms. Studies have observed that mangrove deforestation is occurring in the Philippines. Thus, monitoring of mangrove extent and fragmentation for rehabilitation planning is necessary to prevent further mangrove cover loss. The utilization of free satellite imagery in mangrove monitoring helps in this enterprise as it reduces the need for expensive field activities. Furthermore, it allows researchers to perform spatio-temporal analyses to observe patterns with respect to time and location. This study analyzed the mangrove loss and growth patterns from 2000 to 2020 in Region IV-B MIMAROPA, Philippines – known to house large amounts of mangrove cover – using Landsat 5, 6, 8. Since fragmentation is associated with deforestation, it was also analyzed using the ZonalMetrics toolbox for ArcGIS Pro 2.8. The results showed that Region IV-B experienced mangrove cover increase with only a few cities/towns that suffered significant deforestation. The change pattern analysis showed that most cities/towns were able to strongly preserve the mangroves, with more mangrove gain than loss. The cities/towns are then categorized for their increasing/decreasing mangrove area and fragmentation in the form of a quadrant. Many of the cities/towns experienced an increase in fragmentation metric values over time. However, the increase in mangrove areas in these cities/towns, especially in areas that previously did not have them, suggests that there is little fragmentation of existing mangrove patches, but rather conversion from non-mangrove land cover to mangrove cover. Still, there are a few towns that do not belong to this category that show signs of deforestation and fragmentation, which needs urgent action.