Water Erosion Potential (SA Raster)

Dataset Number2093
Dataset TitleWater Erosion Potential (SA Raster)
CustodianData Authority: Department for Environment and Water
Data Provider: Department for Environment and Water

Description

DescriptionWater Erosion Potential (SA Raster) provides a numeric rating in each raster cell of the potential for sheet or rill erosion in the event that vegetation or other ground cover has been removed (e.g. by fire, over-grazing, land clearance). The assessment is based on mapping of slope and spatial predictions of inherent soil erodibility characteristics. The following erosion potential classes are suggested (but not mandated): 0 - 500 Low; >500 - 3000 Moderately low; >3000 - 5000 Moderate; >5000 - 6500 Moderately High; >6500 - 8000 High; >8000 - 9000 Very high; >9000 - 10000 Extreme. This dataset is a composite of (1) Southern agricultural zone: disaggregation prediction modelling and mapping, based on legacy polygon-based soil landscape mapping, and (2) Northern rangelands: quantitative scoring of water erosion potential from first principles based on national predictive soil and landscape map layers (from the Soil and Landscape Grid of Australia). Raster values have been multiplied by the value 10,000 and converted to a 16-BIT (pixel depth) unsigned integer (pixel type) to reduce file size. To convert the integer values back to the 0-1 continuous scoring system (32-BIT floating point) divide values by 10,000.
UsageThis dataset is for use in landscape biophysical modelling that requires fine-resolution estimates of the potential (inherent susceptibility) of land for soil erosion by water (based on slope and stability of soil profiles), assuming that protective vegetation or other ground cover has been removed. Sample map can be downloaded from Enviro Data SA. Spatial data download is available from Data SA.

Data Quality

LineageThe methodology used in the northern rangelands is described by Hobbs TJ, Armstrong D, Wenham D, Howell S, Spencer J, Maconochie J, Facelli F, Brandle R, Bowen Z & Fitzgerald L (2017). Flora and fauna communities of the Cooper-Eromanga Basin, DEWNR Technical report 2017/23, Government of South Australia, Department of Environment, Water and Natural Resources / Department of the Premier and Cabinet, Adelaide. In the southern agricultural zone, a digital soil mapping approach was used. Representative training site data were collated from Land condition monitoring site assessments (using TopoRWater ratings) and probabilistic pseudo-sites obtained from stratified random sampling of representative map units from existing polygon-based water erosion potential mapping. During the stratified random sampling of pseudo-sites, care was taken to preserve the expected frequency of severity for water erosion potential based on existing polygon-based soil mapping. A deterministic environmental correlation prediction model was then developed using data extracted at the training sites from an array of potential explanatory terrain, climate, and remote sensing raster layers. The least absolute shrinkage and selection operator (LASSO; Tibshirani 1996) model was used to derive a deterministic relationship between the target (erosion potential) and covariate (other mapped environmental) layers, from which a prediction layer was subsequently generated. The rangelands approach (Hobbs et al 2017) was used across the entire State, and then the Lasso-derived disaggregation model was super-imposed for southern South Australia.
CompletenessComplete. The spatial data is subject to amendment as and when more data become available.
Positional AccuracyEstimated accuracy is 50 metres. Accuracy cannot be assumed at the paddock level.

Geographic Extent

Extent NameSouth Australia
Min Easting or Longitude129
Min Northing or Latitude-38.25
Max Easting or Longitude141
Max Northing or Latitude-26

Dataset Status

Initially Acquired5/04/2017
Last Updated5/04/2017
Update FrequencyAs required
Maintenance MethodAs required
AusGOALCC BY (Attribution)

Attributes

TableNameField AliasData TypeDescription
LANDSCAPE.SoilGrid_Erosion_WaterValueValueIntegerPotential for sheet or rill erosion (0 - 0.05 Low; >0.05 - 0.3 Moderately low; >0.3 - 0.5 Moderate; >0.5 - 0.65 Moderately High; >0.65 - 0.8 High; >0.8 - 0.9 Very high; >0.9 - 1 Extreme)

Contact Information

OrganisationDepartment for Environment and Water
Science Monitoring and Knowledge
Postal AddressGPO Box 1047

ADELAIDE
5001
EmailDEWNR.CustomerServiceCentre@sa.gov.au