Marine Biotope Classification:  A New System of Habitat Classification in Victorian Waters

Summary

Habitat mapping forms a basis for defining, valuing and monitoring the coastal environment.  However, the benefits of habitat mapping to management and research are only realised when physical habitats can be linked with biodiversity values and condition in a standardised way.  The Department of Environment, Land, Water & Planning (DELWP) has embarked on a project to collate, centralise and map Victoria’s marine habitats under a new hierarchical system of classification with the biotope as the central mapping unit.  Biotopes and biotope complexes (as Ecological Vegetation Classes, EVCs) have been adopted in terrestrial vegetation mapping in Australia but to date have not been applied comprehensively in the marine environment.  The project aims to drive a step-change in the resolution and interpretability of marine assets, values and condition mapping in Victoria.  This will be achieved in part by incorporating high resolution remote sensing data products that have become the industry standard and the use methods that are scalable to the state-level.

A new classification system, known as the Combined Biotope Classification Scheme (CBiCS), was developed which adapts two established international classification schemes: the European biotope classification scheme (JNCC-EUNIS) and the US Coastal and Marine Ecological Classification Standard (CMECS).  These international systems differ in their approach but have been adopted successfully in their respective jurisdictions, with the EUNIS maturing to the point of linking with biodiversity conservation legislative instruments.  CBiCS scheme provides a hierarchy for classifying marine physical habitats and biotopes.  The scheme has six components: biogeographic setting, aquatic setting, water column setting, geoform component, substratum component and biotic component.  These components, and the hierarchical levels of classification within each component, lead a user through a classification process that results in standardised mapping classes aligned to the resolution of the input data.  For example, classification by experienced biologists of high resolution remote sensing data, collected in an area with good coverage of ground-truthing, can lead directly to a biotope classification.  Importantly, the scheme can also lead to an ecologically relevant higher-level classification where input data are of a lower resolution or where uncertainty is high. We will present results for Port Phillip Bay, the first area to be handled in the project.  Key habitat complexes dealt with include deep canyon reefs, high energy kelp beds, seagrass beds, drift algal beds, sand and mud beds, mangroves, saltmarshes and intertidal complexes.  We will outline the key input data used for biotope mapping, the methods used, the challenges encountered and the infrastructure and information required to sustain and develop the system into the future.  We will present an applied example of how biotope classification can underpin condition and sensitivity assessment to inform monitoring and management.  We will also present an example of how biotope classification can integrate with ecosystem accounting.  Finally, we will identify how the hierarchical classification scheme can operate in a data deficient environment to focus infill studies and in situations where citizen scientists interact with monitoring programs.