Structure of Subsoil (degree of limitation)

Dataset Number1067
Dataset TitleStructure of Subsoil (degree of limitation)
CustodianData Authority: Department for Environment and Water
Data Provider: Department for Environment and Water

Description

DescriptionSoil structure in this assessment refers to the degree of resistance offered by the soil to root penetration and seedling emergence, to the free movement of air and water, and to the ease of cultivation and other surface management operations. Poor subsoil structure is commonly attributable to sodic or dispersive clay, although in soils where there is an abrupt break between the topsoil and subsoil, non dispersive materials can impede water, air movement and root growth. Poorly structured subsoils at shallow depth present a greater limitation than those which are deeper in the profileSELECT 1 FROM DUAL; therefore the assessment of subsoil structure is an integration of structure type and depth. Poorly structured but non dispersive subsoils have coarse blocky or prismatic aggregates, or are massive and hard. Six Structure of Subsoil analysis data classes (including not applicable) have been supplied as percentage values of Soil Landscape Map Units to be used for the calculation of spatial data statistics. Note: the sum of all percentage values for each map unit totals one 100%. Soil Landscape Map Units are categorised INTO five (plus not applicable) legend categories (STRUCT_SUB) according to the most limiting subsoil structure condition, provided that it accounts for more than 30% of the area. Two additional legend categories identify land where there are limited occurrences (ie 10 - 30%) of soil structure limitation.
UsageLink to Soil Attribute Descriptions. This dataset has been derived from the Soil Landscape Map Units spatial dataset to be used for map creation or the calculation of spatial data statistics. Used to supply Government, community groups, industry and the general public with up to date regional, subregional and catchment level land and soil attribute information for southern South Australia. The aim is to produce maps, statistics and reports displaying and describing: Land and soil attributes within southern South AustraliaSELECT 1 FROM DUAL; Land surface features affecting land use, land management and productivitySELECT 1 FROM DUAL; Limitations / suitability of land and soil for a range of agricultural and other uses. Independent professional advice should be sought before using this in commercial decisions. Further information: soil and land attributes. Structure of Subsoil (degree of limitation) dataset can be viewed on NatureMaps (>Soils>Soil Physical Condition Attributes). Spatial data downloads are available from Data SA.

Data Quality

LineageThe dataset is based on an interpretation of 1:40,000 stereo colour aerial photography and limited field inspection of landscapes and soils by soil scientists. Soil Landscape Map Unit boundaries were determined after an integration of field observations and recordingsSELECT 1 FROM DUAL; laboratory analysesSELECT 1 FROM DUAL; stereoscopic examination of aerial photographsSELECT 1 FROM DUAL; understanding of regional landscape processes and stratigraphySELECT 1 FROM DUAL; existing soil and geological mapping data. To avoid inconsistencies and confusion, any updates to the Soil and Land Attribute mapping are to be managed by DEWNR Soil and Land Program. This data has been released under a Creative Commons licence. Where products are derived from this data, DEWNR are to be acknowledged, and any changes to the original data should be indicated.
CompletenessComplete. The spatial data is subject to amendment as and when more data become available.
Positional AccuracyThe accuracy is to the scale of mapping (50 metres at 1:50,000 and 300 metres at 1:100,000 mapping scale). The spatial data is to be used at the regional, subregional and catchment level, and can be used to provide property overviewsSELECT 1 FROM DUAL; however, cannot be used at the paddock level. South East, Kangaroo Island, Mount Lofty Ranges and the 'bottom' of Yorke Peninsula have been mapped at 1:50,000. Eyre Peninsula, the main part of Yorke Peninsula, Murray Mallee and Northern Agricultural Districts have been mapped at 1:100,000. Map unit boundaries should be treated as transition zones.

Geographic Extent

Extent NameAgricultural Region - South Australia
Min Easting or Longitude132.25
Min Northing or Latitude-38
Max Easting or Longitude141
Max Northing or Latitude-32.25

Dataset Status

Initially Acquired01-JAN-2000
Last Updated01-JUL-2009
Update FrequencyAs required
Maintenance MethodAs required
LicenseingCC BY (Attribution)

Attributes

TableNameField AliasData TypeDescription
Landscape.SALAD_Structure_SubsoilLANSLU CharacterSoil Landscape Map Unit.
Landscape.SALAD_Structure_SubsoilSTRUCT_SUB CharacterDegree of limitation due to subsoil structure. (Legend category. See layer file for descriptions).
Landscape.SALAD_Structure_SubsoilP1 NumberPercentage of map unit with a low degree of limitation to subsoil structure (more than 60 cm depth to dispersive claySELECT 1 FROM DUAL; more than 30 cm depth to poorly structured non dispersive clay).
Landscape.SALAD_Structure_SubsoilP2 NumberPercentage of map unit with a moderately low degree of limitation to subsoil structure (30 to 60 cm depth to dispersive claySELECT 1 FROM DUAL; 20 to 30 cm depth to poorly structured non dispersive clay).
Landscape.SALAD_Structure_SubsoilP3 NumberPercentage of map unit with a moderate degree of limitation to subsoil structure (20 to 30 cm depth to dispersive claySELECT 1 FROM DUAL; 10 to 20 cm depth to poorly structured non dispersive clay).
Landscape.SALAD_Structure_SubsoilP4 NumberPercentage of map unit with a high degree of limitation to subsoil structure (10 to 20 cm depth to dispersive claySELECT 1 FROM DUAL; less than 10 cm depth to poorly structured non dispersive clay).
Landscape.SALAD_Structure_SubsoilP5 NumberPercentage of map unit with a very high degree of limitation to subsoil structure (less than 10 cm depth to dispersive clay).
Landscape.SALAD_Structure_SubsoilPX NumberPercentage of map unit which is not applicable.

Contact Information

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

ADELAIDE
5001
EmailDEWNR.CustomerServiceCentre@sa.gov.au