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  • Seafloor classification of the bathymetry dataset from the Queen Charlotte Sound / Tōtaranui and Tory Channel / Kura Te Au Hydrographic Survey LINZ Project HYD-2016/17-01 (HS51). Classification of the multibeam data based on the backscatter intensity as a proxy for substrate type. Classification was done using the ArcMap Image Classification tool using four classes. Training areas where picked to identify areas from high to low backscatter. These data are in raster geotiff format and include ESRI layer files and QGIS GML files for symbology.

  • The slope of the bathymetry dataset from the Queen Charlotte Sound / Tōtaranui and Tory Channel / Kura Te Au Hydrographic Survey LINZ Project HYD-2016/17-01 (HS51). For each cell of bathymetry, the Slope is the maximum rate of change in value from that cell to its neighbors. Basically, the maximum change in elevation over the distance between the cell and its eight neighbors identifies the steepest downhill descent from the cell. These data are in raster geotiff format and include ESRI layer files and QGIS GML files for symbology.

  • The rugosity of the bathymetry dataset from the Queen Charlotte Sound / Tōtaranui and Tory Channel / Kura Te Au Hydrographic Survey LINZ Project HYD-2016/17-01 (HS51). Rugosity (or roughness) of the seafloor is the ratio of surface area to planar area, and is a measure of terrain complexity. Calculated over 3 x 3 neighbouring cells. In the benthic environment, ecological diversity can generally be correlated with environmental complexity. As such, rugosity is often used to help identify areas with potentially high biodiversity. These data are in raster geotiff format and include ESRI layer files and QGIS GML files for symbology.

  • Geochemical data set comprising of major and trace element analyses of phosphorite nodules from deposits located around offshore New Zealand.

  • Using seafloor image data to build single-taxon and community distribution models for seabed fauna in New Zealand waters. Understanding the spatial distributions of seabed biodiversity is essential for effective management of the effects of human activities. However, existing knowledge of seabed faunal distributions comes overwhelmingly from records of museum specimens and fisheries and research trawl bycatch. Data from such sources have been used to build models that predict species and community distributions on the basis of correlations with environmental gradients but because these models are based on presence-only data from disparate sources and times, their predictions are considered uncertain. To improve understanding of seabed fauna distributions around New Zealand, we are developing a new database of occurrences and population densities based entirely on quantitative data from seabed photographic surveys designed to sample these fauna. By modelling the spatial relationships between taxon occurrences and environmental gradients across the region, we are able to predict the likelihood of individual taxa and communities being present in as-yet unsampled areas. In the first phase of the project, we concentrated on Chatham Rise; a region of high importance to commercial fisheries and with the highest density of existing seabed imagery. The models developed here were the first abundance-based models of benthic distributions in the New Zealand region at these spatial scales. In the second phase, we expanded the domain of the predictive models to encompass Campbell Plateau, in the south-eastern sector the EEZ. Combining data from Chatham Rise and Campbell Plateau in a single dataset of benthic invertebrate taxon occurrences and population densities enabled development of up-dated predictive distribution models for a range of individual invertebrate taxa, as well as models of the spatial variability in overall community composition. Rasters are in a geotiff format at a 1000 m resolution cell size and have their relevant projections written in their files.

  • Using seafloor image data to build single-taxon and community distribution models for seabed fauna in New Zealand waters. Understanding the spatial distributions of seabed biodiversity is essential for effective management of the effects of human activities including fishing and mining. To improve understanding of seabed fauna distributions, we are developing a new database of benthic invertebrate occurrences in New Zealand waters by assembling quantitative data from all available seabed photographic surveys. By modelling the spatial relationships between taxon occurrences and environmental gradients across the region, we are able to predict the likelihood of individual taxa and communities being present in as-yet unsampled areas. In the first phase of the project, we concentrated on Chatham Rise; a region of high importance to commercial fisheries and with the highest density of available seabed imagery. Predictions from the models developed here are the first abundance-based models of benthic distributions in the New Zealand region and are the best-informed representations of seabed distributions on Chatham Rise to date, providing a resource that will have applications in marine environmental management and ecosystem research. All rasters are in a geotiff format at a 1000 m resolution cell size and projected to WGS 84 / Mercator 41 - EPSG:3994 coordinate system.