The Catchment Scale Land Use of Australia shows a single dominant land use for a given area, based on the primary management objective of the land manager (as identified by state and territory agencies). As a seamless spatial dataset for Australia, it can be used to identify, map and analyse high level land use categories (such as irrigated horticulture and dryland cropping) and more specific land use categories such as grapes, cotton, cereals, sugar and tree fruits. These categories can be extracted or combined with other spatial datasets to provide new insights and analysis concerning land use in Australia.
Updates to the Catchment Scale Land Use of Australia are usually released annually. These annual updates selectively update the existing information in some areas, with new mapping as completed by one or more contributing jurisdictions, as land use changes of using improved methods.
Land use is classified according to the Australian Land Use and Management (ALUM) Classification, a three-tiered hierarchical structure. There are five primary classes, identified in order of increasing levels of intervention or potential impact on the natural landscape. Water is included separately as a sixth primary class. Primary and secondary levels relate to the principal land use. Tertiary classes may include additional information on commodity groups, specific commodities, land management practices or vegetation information. The primary, secondary and tertiary codes work together to provide increasing levels of detail about the land use. Land may be subject to a number of concurrent land uses. For example, while the main management objective of a multiple-use production forest may be timber production, it may also provide conservation, recreation, grazing and water catchment land uses. In these cases, production forestry is commonly identified in the ALUM code as the prime land use.
The operational scales of catchment scale mapping vary according to the intensity of land use activities and landscape context. Scales range from 1:10 000 and 1:25 000 for irrigated and peri-urban areas, to 1:100 000 for broadacre cropping regions and 1:250 000 for the semi-arid and arid pastoral zone. The date of mapping generally reflects the intensity of land use. The most current mapping occurs in intensive agricultural areas; older mapping generally occurs in the semi-arid and pastoral zones. The primary classes of land use in the ALUM Classification are: Conservation and natural environments - land used primarily for conservation purposes, based on maintaining the essentially natural ecosystems present Production from relatively natural environments - land used mainly for primary production with limited change to the native vegetation Production from dryland agriculture and plantations - land used mainly for primary production based on dryland farming systems Production from irrigated agriculture and plantations - land used mostly for primary production based on irrigated farming Intensive uses - land subject to extensive modification, generally in association with closer residential settlement, commercial or industrial uses Water - water features (water is regarded as an essential aspect of the classification, even though it is primarily a land cover type, not a land use).
The Catchment Scale Land Use of Australia is often accompanied by a commodities dataset containing more details about specific agricultural commodities which have been mapped.
