caa a22 4500 445819677 CHVBK 20180317145240.0 cr unu---uuuuu 170323e20110601xx s 000 0 eng 10.1007/s00338-011-0731-9 doi (NATIONALLICENCE)springer-10.1007/s00338-011-0731-9 AUV-based bed roughness mapping over a tropical reef [Elektronische Daten] [Sergio Jaramillo, Geno Pawlak] Identifying fixed bed roughness scales of hydrodynamic relevance to waves and currents is challenging around coral reefs due to their highly inhomogeneous bathymetry. In order to characterize the spatial variability in reef roughness, a quantitative analysis of high-resolution sidescan sonar backscatter is performed for the identification of distinct substrates around a tropical reef and is related to echo sounder-based roughness measurements. Data were collected in the vicinity of the Kilo Nalu Observatory on the south shore of Oahu using sidescan sonar and a narrow beam echo sounder incorporated in a REMUS-100 (Remote Environmental Monitoring UnitS) autonomous underwater vehicle (AUV). With basic statistics and principal component analysis of variables derived from the backscatter data, it is possible to discriminate between areas of rough reef, bare reef, and rippled sand. Echo sounder-derived spectral analysis did not reveal dominant length scales. However, by combining the seabed classification obtained from sidescan measurements with echo sounder data, spectral root mean square (RMS) height values of approximately 3.3cm and 7.3cm are assigned to the bare reef and rough reef areas, respectively, for roughness with wavelengths between 0.2 and 6m. Springer-Verlag, 2011 Seabed roughness nationallicence Sidescan sonar nationallicence Substrate classification nationallicence Autonomous underwater vehicle nationallicence Jaramillo Sergio Department of Ocean and Resources Engineering, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, 96822, Honolulu, HI, USA aut Pawlak Geno Department of Ocean and Resources Engineering, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, 96822, Honolulu, HI, USA aut Coral Reefs Springer-Verlag 30(2011-06-01), 11-23 0722-4028 30<11 2011 30 338 https://doi.org/10.1007/s00338-011-0731-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00338-011-0731-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Jaramillo Sergio Department of Ocean and Resources Engineering, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, 96822, Honolulu, HI, USA aut NATIONALLICENCE 700 1- Pawlak Geno Department of Ocean and Resources Engineering, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, 96822, Honolulu, HI, USA aut NATIONALLICENCE 773 0- Coral Reefs Springer-Verlag 30(2011-06-01), 11-23 0722-4028 30<11 2011 30 338 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer