Coral reefs, among the most vulnerable ecosystems worldwide, provide populations with a wide range of resources, including food, jobs, and coastal protection. Human activities such as fishing and climate change affect reefs in a variety of ways, and current research has begun to examine the complex relationships between these activities and coral reef health. So that humans can continue to use the reef resources on which they depend, researchers must identify and mitigate stressors through effective land management strategies.
NOAA’s Pacific Islands Fisheries Science Center analyzed the amount of impervious surface, cultivated land, and pasture on each of the Pacific islands using NOAA’s Coastal Change Analysis Program (C-CAP) data. Percentage of impervious surface, cultivated land, and pasture were selected because of their link to the amount and type of runoff that occurs. Impervious surface area can be informative of the amounts of sediment, debris, residue, and other pollutants that wash into streams and eventually drain into soil and groundwater or coastal waters. Agricultural lands, including cultivated land and pastures, are also linked to coral reef degradation through soil erosion and the subsequent introduction of sediments, nutrients, and pollutants into coastal waters.
Current management efforts in Hawaii are returning to the “ridge to reef” approach for managing watershed resources. Land cover data are often examined to understand what types of land and watershed alterations have occurred in a given area, including the extent to which runoff and the resulting introduction of sediment and pollutants into nearshore areas might occur. This information provides a baseline to better inform current and future management decisions, and allow for comparisons in other Pacific islands.