Comparison of echogram measurements against data expectations and assumptions for distinguishing seafloor substrates

Zimmermann, Mark and Rooper, Christopher N. (2008) Comparison of echogram measurements against data expectations and assumptions for distinguishing seafloor substrates. Fishery Bulletin, 106(3), pp. 293-304.

[img] PDF (The document's language is English .) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (814Kb)
Official URL: http://fishbull.noaa.gov/1063/zimmermann.pdf

Abstract

Defining types of seafloor substrate and relating them to the distribution of fish and invertebrates is an important but difficult goal. An examination of the processing steps of a commercial acoustics analyzing software program, as well as the data values produced by the proprietary first echo measurements, revealed potential benef its and drawbacks for distinguishing acoustically distinct seafloor substrates. The positive aspects were convenient processing steps such as gain adjustment, accurate bottom picking, ease of bad data exclusion, and the ability to average across successive pings in order to increase the signal-to-noise ratio. A noteworthy drawback with the processing was the potential for accidental inclusion of a second echo as if it were part of the first echo. Detailed examination of the echogram measurements quantified the amount of collinearity, revealed the lack of standardization (subtraction of mean, division by standard deviation) before principal components analysis (PCA), and showed correlations of individual echogram measurements with depth and seafloor slope. Despite the facility of the software, these previously unknown processing pitfalls and echogram measurement characteristics may have created data artifacts that generated user-derived substrate classifications, rather than actual seafloor substrate types.

Item Type: Article
Title: Comparison of echogram measurements against data expectations and assumptions for distinguishing seafloor substrates
Personal Creator/Author:
CreatorsEmail
Zimmermann, Mark
Rooper, Christopher N.
Refereed: Yes
Journal or Publication Title: Fishery Bulletin
Volume: 106
Number: 3
Page Range: pp. 293-304
Date: 2008
ISSN: 0090-0656
Issuing Agency: United States National Marine Fisheries Service
Subjects: Biology
Ecology
Fisheries
Item ID: 8838
Depositing User: Patti M. Marraro
Date Deposited: 12 Jun 2012 17:53
Last Modified: 12 Jun 2012 17:53
URI: http://aquaticcommons.org/id/eprint/8838

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...