Assessing Coral Reef Degradation Patterns Using Remote Sensing and GIS

Coral reefs are among the most productive and biologically diverse marine ecosystems, yet they are increasingly threatened by climate change, ocean warming, and anthropogenic pressures. Effective monitoring of coral reef dynamics is essential for informing conservation strategies and assessing the effectiveness of Marine Protected Areas (MPAs). This study applies Remote Sensing and Geographic Information Systems (GIS) to analyze spatiotemporal changes in coral reef habitats along the Watamu–Malindi Marine Protected Area on the Kenyan coast.

Multitemporal Sentinel-2 satellite imagery was used to map and monitor coral reef extent and condition over selected time periods. Pre-processing steps, including atmospheric correction, cloud masking, and water column correction, were performed to enhance image quality for shallow marine environments. Supervised classification techniques were then applied to delineate coral reef habitats from surrounding benthic features such as sand and seagrass. Change detection analysis was conducted to quantify spatial and temporal variations in reef distribution and identify areas of degradation or stability.

The results indicate significant spatial variability in coral reef condition, with some reef zones showing signs of degradation potentially linked to environmental stressors, while others within protected zones demonstrate relative stability. The integration of GIS allowed for spatial visualization of reef changes and facilitated comparison between different management zones within the MPA.

The study demonstrated the effectiveness of combining Remote Sensing and GIS for cost-efficient, large-scale monitoring of coral reef ecosystems. The findings provide valuable insights for marine resource managers and conservation planners in assessing reef health trends and strengthening protection strategies. The approach supports evidence-based decision-making for sustainable coastal and marine ecosystem management in the face of increasing climate-related pressures.