Evaluating the Suitability of Multi-Scale Terrain Attribute Calculation Approaches for Seabed Mapping Applications

Abstract

The scale dependence of benthic terrain attributes is well-accepted, and multi-scale methods are increasingly applied for benthic habitat mapping. There are, however, multiple ways to calculate terrain attributes at multiple scales, and the suitability of these approaches depends on the purpose of the analysis and data characteristics. There are currently few guidelines establishing the appropriateness of multi-scale raster calculation approaches for specific benthic habitat mapping applications. First, we identify three common purposes for calculating terrain attributes at multiple scales for benthic habitat mapping: (i) characterizing scale-specific terrain features, (ii) reducing data artefacts and errors, and (iii) reducing the mischaracterization of ground-truth data due to inaccurate sample positioning. We then define criteria that calculation approaches should fulfill to address these purposes. At two study sites, five raster terrain attributes, including measures of orientation, relative position, terrain variability, slope, and rugosity were calculated at multiple scales using four approaches to compare the suitability of the approaches for these three purposes. Results suggested that specific calculation approaches were better suited to certain tasks. A transferable parameter, termed the ‘analysis distance’, was necessary to compare attributes calculated using different approaches, and we emphasize the utility of such a parameter for facilitating the generalized comparison of terrain attributes across methods, sites, and scales.

Keywords:

• benthic habitat mapping
• geomorphometry
• multibeam echosounder
• scale
• seabed mapping
• terrain analysis

Acknowledgements

Thank you to the Fisheries and Marine Institute’s School of Ocean Technology and Centre for Applied Ocean Technology for access to the boat and technical personnel and to Kirk Regular and Eugene Antle for D’Argent Bay data collection. Thank you to Alexandre Schimel for comments and suggestions on the manuscript.

Disclosure statement

The authors declare no competing interests.

Data availability statement

The GEBCO_2019 bathymetry data supporting the findings in this study are available for free from the GEBCO data portal: https://www.gebco.net/data_and_products/gridded_bathymetry_data/gebco_2019/gebco_2019_info.html. Access to the D’Argent Bay multibeam data will be considered upon request by the authors.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This work was partly supported by Fisheries and Oceans Canada’s Coastal Environmental Baseline Program and by a Canada Research Chair program through a chair in Ocean Mapping to KR. BM was partially supported by the Fisheries and Marine Institute’s School of Ocean Technology, and by an International Postdoctoral Fellowship awarded through the Ocean Frontier Institute/Canada First Research Excellence Fund. Funds allocated to VL by the University of Florida Senior Vice President for Agriculture and Natural Resources were used to support collaboration with BM at the University of Florida School of Forest, Fisheries, and Geomatics Sciences.