The coastal lands of NSW cover a richness of geology, soils, landscapes and vegetation. From the broad flat lands close to the eastern seaboard to the steep escarpments along the edge of the tablelands, the variety of land types makes it difficult to find similarities between areas and hence com- pare land uses, land management and conservation values. 

Environment Australia has divided Australia into a series of ‘bioregions’, called IBRA Regions, which are a unique combination of biological and physical features. However, these are relatively large and do not adequately describe the unique features of much of eastern NSW. What was needed was a system of bioregions that would define and describe the land between the ocean and the western plains with greater detail. 

Apart from the advantages of having a consistent system to describe the biological and physical characteristics of NSW, it is important that bioregions be established for the State. At present, NSW is the only state or territory in Australia without a systematic approach to bioregionalisation. Such a system provides a basis for planning, including conservation planning, within the State. 

For the past four years NPA has been developing a system of bioregionalisation for eastern NSW (funded by a National Estate grant through the NSW Heritage Council). This system complements that developed previously by NPA for western NSW (Nature Conservation in Western New South Wales by Gethin Morgan and Jenny Terrey, 1992). The bioregions of western NSW were mainly based upon differences in the geology and soils found in inland NSW, whereas the bioregionalisation of eastern NSW was based upon relief, altitude and surface geology (regolith), with some use of climate and vegetation cover. The report, titled Bioregionalisation of Eastern New South Wales, was produced by Martin Denny in 1999. 

The bioregionalisation project divides the six IBRA Regions covering eastern NSW into 49 Sub-Regions and 91 Provinces. For each of these sub-regions and provinces, there is information about the vegetation, existing land cover, geology, soils and degree of conservation. The report highlights where bioregions are not adequately conserved within NSW; only 35% of the bioregions are fully represented within existing conservation areas. The bioregions were developed using a geographic information system, and the digitised boundaries of each sub-region and province will be available electronically. 

This system has already been of use, with bioregions providing information about the conservation assessment of specific areas. The NSW NPWS has adopted the system of sub-regions for coastal NSW, together with that previously developed for western NSW by NPA, to develop an overall conservation assessment of the State.

* Martin Denny is an environmental consultant and partner in Mount King Ecological Surveys. He has been involved with the conservation movement for many years.