Modeling Conservation Priority and Potential Restoration Areas of Mangroves in Pangasinan, Ilocos Region using Spatially Explicit Models

Payopay, John Paul

Mangroves provide critical ecosystem services yet face extensive habitat loss and climate impacts that necessitate urgent action This study addressed the lack of integrated multi-criteria approaches for identifying mangrove restoration and conservation priority sites in Pangasinan by developing a spatially explicit framework to guide management decisions. The primary objective was to identify areas that have high restoration potential and conservation priority that are based on habitat suitability. land use/land cover (LULC), and landscape connectivity. This research utilized Sentinel-2 images for LULC classification and mangrove extent mapping. Alongside a suite of bioclimatic, marine, soil, and topographic variables for species distribution modeling (SDM). An ensemble of seven SDM algorithms predicted mangrove habitat suitability across coastal Pangasinan. Receiver Operating Characteristics (ROC) and True Skill Statistics (TSS) were used as model performance metrics. Landscape connectivity was assessed using graph theory. Incorporating local and delta metrics. These analyses were integrated to derive a Restoration Potential Index (RPI) and a Conservation Priority Index (CPI) for the province. The study estimated the current mangrove extent in Pangasinan at 3139.48 ha (accuracy=97.64% : K=0.953). The ensemble SDM identified 40,664 ha of theoretically suitable mangrove habitat, with soil bulk density and topobathymetry being key predictors (ROC=0.995 : TSS +0.921). The RPI analysis drew 10,340 ha as potentially restorable, primarily those in former aquaculture pond within Binmaley, Lingayen, and Dagupan City. The CPI identified 321.76 ha of high-priority conservation areas, concentrated along the Agno River system where high habitat suitability converged with critical landscape connectivity. The identified priority sites are crucial for maintaining regional mangrove biodiversity, enhancing ecosystem connectivity essential for climate adaptation, and sustaining vital ecosystem services. The findings underscore the importance of protecting irreplaceable connector patches and strategically restoring areas that bolster network resilience. This integrated privatization framework provides a scientifically robust basis targeted for mangrove conservation and restoration planning in Pangasinan. The methodology is transferable to other coastal regions offering a valuable tool for informing coastal zone management policies, protected area planning, and aligning local actions with national biodiversity strategies and international conservation commitments.