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Marine/Coastal GIS and Acoustic Remote Sensing. Specialty Group Sponsors: Coastal and Marine Geography Geographic Information Science and Systems. AAG Annual Meeting, Denver April 8, 2005. Photo by. Benthic Terrain Modeling Algorithms and Web Distribution.
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Marine/Coastal GIS andAcoustic Remote Sensing Specialty Group Sponsors: Coastal and Marine Geography Geographic Information Science and Systems AAG Annual Meeting, Denver April 8, 2005 Photo by
Benthic Terrain Modeling Algorithms and Web Distribution D.J. Wright, E. Lundblad*, E. Larkin^, R. Rinehart, Dept. of Geosciences, Oregon State University J. Murphy NOAA Coastal Services Center AAG Annual Meeting, Denver April 8, 2005 Photo by
National Marine Sanctuaries Map courtesy of NOAA National Marine Sanctuary System
Artwork by Jayne Doucette, Woods Hole Oceanographic Institution
FBNMS: Some Major Issues • Natural & human impacts • Crown-of-thorns invasion, hurricanes, bleaching • Illegal fishing, sewage outfall Photos courtesy of NOAA National Marine Sanctuary System
FBNMS cont. & Research ??s • Prior to 2001… • Sanctuary largely unexplored below depths of ~30-60 m • no comprehensive documentation of the plants, animals, and submarine topography. • Little is known of tropical “twilight zone” • shelf-edge (50-120 m deep) of coral reef habitats throughout the world • Best combo of terrain analysis techniques? • Extension of satellite-based scheme • What is viable classification acoustically?
OrSt & USFMultibeam Surveys to date By OrSt grad student Emily Lundblad
Shallow Multibeam(May 2001, November 2002) • Kongsberg-Simrad EM-3000 • Fans out 121 beams at 130 deg. • Swaths 3-4 times water depth • Depths in 3-150 m range at survey speeds of 3-12 knots • cm-resolution w/ dGPS
(after Weiss 2001) Bathymetric Position Index(from TPI, Jones et al., 2000; Weiss, 2001; Iampietro & Kvitekk, 2002) Measure of where a point is in the overall land- or “seascape” Compares elevation of cell to mean elevation of neighborhood
Bathymetric Position Index bpi<scalefactor>= int((bathy - focalmean(bathy, annulus, irad, orad)) + .5) Algorithm compares each cell’s elevation to the mean elevation of the surrounding cells in an annulus or ring. resolution = 3 m irad = 2 cells (6 m) orad = 4 cells (12 m) scalefactor = resolution * orad = 36 m |---2---| |---------4-------| • Negative bpi = depression • Positive bpi = crest • Zero bpi = constant slope or flat -3m-
BPI Zone and Structure Classification Flowchart Emily Lundblad, OrSt M.S. Thesis
Fish Abundance & BPI Courtesy of Pat Iampietro, CSU-MB, ESRI UC 2003
2005 HURL Sub & ROV surveys Ka‘imikai-o-Kanaloa Pisces IV or V RCV-150
Rugosity • Measure of how rough or bumpy a surface is, how convoluted and complex • Ratio of surface area to planar area Surface area based on elevations of 8 neighbors 3D view of grid on the left Center pts of 9 cells connected To make 8 triangles Portions of 8 triangles overlapping center cell used for surface area Graphics courtesy of Jeff Jenness, Jenness Enterprises, and Pat Iampietro, CSU-MB
American Samoa Benthic Terrain Viewer scallywag.science.oregonstate.edu/website/AmSamoa/viewer.htm … or via dusk.geo.orst.edu/djl/samoa Link to Samoan version of site Overview Map Zoom to study area Active tool display Links to help, data download and info pages
Samoan Collaborations & Products • OSU, NOAA & AS GIS User Group • Benthic classifications for benthic habitat/MPAs • American Samoa Benthic Terrain Viewer • AS Marine/Coastal Bibliographic Tool • On-island workshops in September 2004 • Benthic Terrain Modeler (ArcGIS 8.x/9.x tool) • 3D Visualizations and movies in Fledermaus • Other work • NOAA Coral Reef Ecosystem Division Mapping • Duke U. Coral reef ecosystem studies
For more information …dusk.geo.orst.edu/djl/samoa Image courtesy of FBNMS
Structure Classification Decision Tree Emily Lundblad, OrSt M.S. Thesis