Application of the Coastal and Marine Ecological Classification Standard to Gosnold Seamount, North Atlantic Ocean

TitleApplication of the Coastal and Marine Ecological Classification Standard to Gosnold Seamount, North Atlantic Ocean
Publication TypeBook Section
AuthorsSowers, D, Dijkstra, JA, Mello, K, Masetti, G, Malik, MA, Mayer, LA
EditorHarris, P, Baker, E
Book TitleSeafloor Geomorphology as Benthic Habitat
Pagination 903-916
Date PublishedNovember 8

This case study applied the Coastal and Marine Ecological Classification Standard (CMECS) to initial characterization of a deep-sea seamount by combining observations from a remotely operated vehicle (ROV) and information derived from multibeam sonar bathymetry and backscatter. Spatial segmentation of the multibeam bathymetry was done using algorithms based on defining bathymorphons resulting in six classes: flats, slopes, ridges, valleys, shoulders, and footslopes. These classes were modified to delineate CMECS “Level 1” geoform units for Gosnold Seamount. Further segmentation of landforms was completed using textural analysis of the sonar backscatter mosaic of the seamount to identify segments of the same landform type with similar reflectivity texture. All of the ROV dive video of the seafloor was analyzed manually to create a spreadsheet of 933 georeferenced annotations of organisms and associated substrate types. The dominant sediment type over each 50 m segment of the ROV track was also classified using substrate unit terminology from CMECS into four classes: bedrock (10% of ROV track), fine unconsolidated sediments on bedrock (84%), coral rubble (1%), and sand (5%). Eleven genera of corals, two classes of sponges, and four classes of echinoderms were observed along the track, with glass sponges dominating the annotation and abundance counts. Nominal regression revealed that depth, temperature, and sediment type were significant predictors of individual coral along the ROV track (P<.001, P<.001, P<.001, respectively). In contrast, slope, sediment type and dissolved oxygen were significant predictors of sponge distribution along the track. In summary the application of CMECS to Gosnold Seamount provided a useful systematic framework for structuring geoform, substrate, and biotic classification of benthic habitat. Using this standard, in combination with the semiautomated seafloor segmentation approach utilized, can provide a consistent and reproducible habitat classification approach for large regions and facilitate comparison of habitats among features.

Refereed DesignationDoes Not Apply