Description: The quality of the habitat information derived from remotely sensed data is determined by the quantitative process of accuracy assessment and ground validation. The purpose of accuracy assessment is to identify and quantify errors in the maps by comparing the attributes of the map versus reference data at various sites. Selected sites were visited in the field for typological validation.
Description: The purpose of this survey data was to collect information on current habitat conditions at random locations throughout the mapping area. Locations were determined by an iterative, GIS-based, stratified random sampling technique to ensure that all bottom classifications would be assessed. This information was used to evaluate the thematic accuracy of the Palmyra Atoll benthic habitat map.
Description: The purpose of this survey was to investigate areas of imagery where uncertainties existed on the photo interpreter's behalf during the decision making process of benthic habitat classification on Palmyra Atoll. This information was incorporated into a fine-scale assessment of the status, abundance, and distribution of marine habitats of Palmyra Atoll.
Description: These are the boundaries for all polygons in the classification scheme, broken out by the Biological Cover, Live Coral Cover, Structure, and Zone fields.
Description: Eighteen biological cover classes were identified that could be mapped through visual interpretation of remotely sensed imagery. Cover classes refer only to the dominant biological component colonizing the surface of the feature and do not address location (e.g., on the shelf or in the lagoon) or structure type. The cover types are defined in a collapsible hierarchy ranging from eight major classes (Algae, Seagrass, Live Coral, Mangrove, Coralline Algae, No Cover, Unclassified and Unknown), combined with a modifier describing the distribution of the dominant cover type throughout the polygon (10%-50%, 50%-90%, and 90%-100%).
Description: The estimated live coral cover is made in the final process of attributing a polygon independent of other live cover types. It is important to remember that both soft and hard coral contribute to this class.
Description: The major geomorphologic coral reef and hard bottom classes includes areas of both shallow and deep-water seafloor with solid substrates including Rock Outcrop, Boulder, Spur and Groove, Individual Patch Reef, Aggregated Patch Reefs, Aggregate Reef, Reef Rubble, Pavement, Pavement with Sand Channels, and Rhodoliths.
Description: Thirteen mutually exclusive zones can be identified from shore to shelf edge corresponding to typical insular shelf and coral reef geomorphology. These zones include: Land, Salt Pond, Shoreline Intertidal, Reef Flat, Lagoon, Back Reef, Reef Crest, Fore Reef, Bank/Shelf, Bank/Shelf Escarpment, Channel, Dredged, and Unknown. Zone refers only to each benthic community’s location and does not address substrate or biological cover types that are found within.