IBRA Subregion Australia Version 7.0 - PED

## **Abstract** 

This dataset and its metadata statement were supplied to the Bioregional Assessment Programme by a third party and are presented here as originally supplied.

Interim Biogeographic Regionalisation for Australia (IBRA) Version 7.0 Bioregions represents a landscape based approach to classifying the land surface of Australia. The framework was first described by Thackway and Cresswell (1995). IBRA 7.0 data consists of two hierarchical `Bioregion' datasets described as part of the regionalisation framework for Australia; 1) Regions - larger scale regional classification of homogenous ecosystems & 2) Subregions - a more localised, finer scale classification of ecosystems within the Region boundaries. Each Bioregion reflects a unifying set of major environmental influences (such as geology, landform patterns, climate & ecological features) which shape the occurrence of flora and fauna associations and their interaction with the physical environment across Australia and its external territories (excluding Antarctica). IBRA Version 7.0 describes 89 Regions and 419 Subregions and is the result of updates to the previous version, IBRA Version 6.1 This record represents Australia-wide IBRA Version 7.0 Regions and Subregions.

## **Purpose** 

IBRA is the National Reserve System's planning framework; it was developed as a fundamental tool for identifying reservation targets towards developing a comprehensive and representative reserve system in Australia.

## **Dataset History** 

IBRA Version 7.0 is the result of changes to certain IBRA 6.1 boundaries with edge-matching along state borders. The updated boundaries were jointly defined by the Commonwealth, State and Territory nature and conservation agencies. There have been significant changes in Queensland and South Australia. In addition the dataset was also updated to more closely conform to the Geoscience Australia (GA) 1:100K Coastline and State borders. Various sources were used to delineate islands - these included the GA 100K Admin layer plus the Australian Maritime Boundaries dataset, a Coral Sea dataset (held in ERIN) and the GA Commonwealth Fisheries 2006 dataset. In South Australia, the work undertaken by the CSIRO to map the `Environments of South Australia' (see Laut, et. al. 1977) has formed the basis for the mapping of IBRA boundaries for the state. In 1995 the environmental association units, described as part of this work, were reviewed and aggregated to initially form IBRA Regions for the first version of IBRA (Version 4.1). In 2000 an update to create IBRA Version 5.1 incorporated a finer scale level of mapping in the IBRA dataset with the delineation of IBRA Subregions; as part of the hierarchy formed by the IBRA framework Subregions are aggregated to form the boundaries of the IBRA Regions. In South Australia, the environmental associations were interpreted again to form the basis for IBRA Subregions. In 2005 the Subregion boundaries in the South Australian pastoral districts were re-interpreted based on an assignment of the pastoral land system mapping units to Subregion groupings. As part of that update, the land system mapping units replaced the CSIRO environmental associations as the smallest units maintained for the IBRA framework in SA. These updates were initially featured in an SA-only draft IBRA layer designated Version 6.2. These updates are now fully incorprated in the national IBRA Version 7.0 dataset with some additional updates.

## **Dataset Citation** 

SA Department of Environment, Water and Natural Resources (2015) IBRA Subregion Australia Version 7.0 - PED. Bioregional Assessment Source Dataset. Viewed 12 October 2016, http://data.bioregionalassessments.gov.au/dataset/e5a6d60a-009c-4fc3-b27d-67ed108b38ba.

Tags: Pedirka subregion, biota
Organization: Bioregional Assessment Program