Coral Reef Applications of Airborne Lidar and Digital Camera Surveys

Recently the USGS Geologic Discipline's Coastal and Marine Geology Program (CMGP) has supported the creation of new capabilities for the synoptic remote sensing of coastal marine and terrestrial environments based on aircraft and satellite sensors. Special emphasis has been placed on the use of aircraft lidar and multi-spectral imaging to map coral reef ecosystem geomorphology, topographic roughness, and habitats at spatial scales finer than 2 meters. Through partnerships with NASA and the NPS, these capabilities have been applied to create highly detailed benthic maps of portions of the Florida reef tract within Biscayne National Park (BISC), Dry Tortugas National Park (DRTO), and the NOAA Florida Keys National Marine Sanctuary.

Remote sensing applications at Dry Tortugas National Park (DRTO). Above Left: ATRIS vessel-track lines overlaid on lidar-based submerged topographic map of DRTO [Enlargement].	ATRIS vessel-track lines overlaid on lidar-based rugosity map of DRTO. Rugosity is an indicator of topographic complexity of the substrate [Enlargement].

In parallel, the Geologic Discipline's Coastal and Marine Geology Program (CMGP) has created an efficient "ground-truthing" capability for the validation of remote-sensing maps of coral reef habitats and submarine topography. This system, the Along-Track Reef Imaging System (ATRIS), is deployed on a small vessel (< 26 feet in length) and incorporates subsystems for navigation, real-time differential GPS positioning, autonomous digital camera benthic imaging, and acoustic bathymetric surveying. In total, these new coastal remote sensing, mapping and point monitoring tools constitute a unique integrated package of instrumentation and software that may be deployed in support of appropriately timed and scaled zoning decisions by management authorities in order to conserve and sensibly exploit near shore marine ecosystems. However, the creation of a map or the collection of a series of observations alone does not enable managers to interactively and objectively undertake "what if" scenario testing of alternative zoning and use policies. Accordingly, a critical need exists for research on methods for the translation of remote sensing surveys and Geographic Information Systems populated with geological and ecological data collected within scientific investigations into conservation applications that are a much higher priority for non-scientifically-trained decision-makers.