- Description
-
It should be noted that this data is now somwhat dated!
Soil degradation refers to any deterioration in the natural physical, chemical or biological properties of a soil, and is a function of soil texture, soil fabric, soil fauna and mineral and organic matter content. Soil degradation reflects the unsuitability of a land-use / management practice on a particular soil type, and manifests itself as soil erosion (eg. loss of the topsoil), compaction – causing loss of water holding capacity and permeability changes, acidification, salinisation, etc.
This issue is particularly relevant to property scale planning and management, but off-site impacts can also be significant. Soil degradation is sensitive to catchment scale changes, particularly where the change is direct.
The soil properties that affect land management, as identified within the Atlas of Australian Soils, have been rated according to their potential to degrade under the land-uses practiced upon them. The land-use data has been rated by intensity into 10 classes. Both ratings are based on expert opinion.
The two rating systems have been combined spatially to produce a land-use practice-soil vulnerability surface, which has been re-classified into 5 classes ranging from low soil degradation hazard (nature conservation areas and/or soils having negligible physical and chemical limitations) through to high hazard (i.e. high intensity land-uses on highly vulnerable soils). The quality and reliability of data is limited by the coarseness of the soils mapping and the difficulties of defining soil classes over vast areas of inherently heterogeneous soil mosaics.
Soil degradation hazard is an issue in many parts of the mid Murray-Darling Basin (Murrumbidgee, Murray-Riverina, Avoca and Loddon River basins) because of limy, powdery soils. This can cause poor crop response, and leave bare erodible ground. The biophysical impacts include loss of topsoil nutrients and organic matter. This results in vegetation re-establishment difficulties and the loss of biodiversity.
In Queensland, the main soil management concerns are on the central to northern coast and correspond with sulphidic, waterlogged and sodic soils (Burdekin, Don, Haughton, Fitzroy, Calliope, Boyne and Ross Rivers). Engineering works associated with land development and other kinds of disturbance, including drainage, cultivation and irrigation, have caused the sulphidic soils to be oxidised, causing sulphuric acid release to waterways. In these areas, sodic soils readily disperse and erode, causing turbid streams. In South Australia the catchment with the poorest rating is the Myponga River catchment. In Victoria the Barwon, Moorabool and Werribee River basins have poor ratings. In Western Australia the catchments with poor ratings are the Esperance Coast, Frankland, Blackwood, Avon, Moore-Hill, Yarra Yarra Lakes and Murchison River basins.
Data are available as:- continental maps at 5km (0.05 deg) cell resolution for the ILZ;
- spatial averages over CRES defined catchments (CRES, 2000) in the ILZ;
- spatial averages over the AWRC river basins in the ILZ.
See further metadata for more detail.
- Download
-
- pa_iccilr9ab__05821axx.xml (Other) 0.00KB - 301 hits
- Date Published
- 1 June 2000
- Date Updated
- 1 October 2010
- Update Frequency
- Not specified
Dataset Information
- data.gov.au Category
- Employment
- Keywords / Tags
- Environment, indicator, land, Land Cover, Land Use, water
- Licence
- Constraints
- Permalink
- http://data.gov.au/4497
Contributing Agency Information
- Agency
- Department of Agriculture Fisheries and Forestry (View all datasets from Department of Agriculture Fisheries and Forestry)
- Jurisdiction
- Commonwealth of Australia
- Agency Program
- Australian Bureau of Agricultural and Resource Economics and Sciences
Dataset Coverage
- Temporal Coverage
- 1 January 1990 to 30 May 2001
- Geospatial Coverage
- Australia
- Granularity
- Not specified
