Water Repellence

Dataset Number1075
Dataset TitleWater Repellence
CustodianData Authority: Department for Environment and Water
Data Provider: Department for Environment and Water

Description

DescriptionWater Repellence is caused by hydrophobic organic materials, mainly waxes, contained in plant remains within the soil. The waxes coat the soil particles causing water to bead on the surface. This causes uneven wetting of the upper part of the soil profile, with large masses of soil remaining dry. Patchy plant establishment, uneven and poor growth usually result, increasing susceptibility to water erosion, wind erosion and sand blasting of newly emerged plants, while also decreasing water use efficiency and contributing to increased recharge (elsewhere due to preferential drainage). Water repellence is most common on acid to neutral sands, but calcareous and more loamy soils can also be affected, although not as severely. Water repellence is tested by observing the absorption INTO a soil sample of either water or 2 M ethanol. This assessment is based on limited soil testing and extrapolation between similar soils in similar environments, hence indicating the potential (rather than actual) extent of the problem. Four Water Repellence attribute (or 'analysis data') classes have been supplied (see 'U1', 'U2' etc in table below, including not applicable) as percentage (areal extent) values of each Soil Landscape Map Unit. Note: the sum of all percentage values for each map unit totals 100%. This analysis data is to be used for the calculation of spatial data statistics. For map display purposes, Soil Landscape Map Units have been categorised INTO 10 legend categories (WATERREPEL), including not applicable, according to the proportion of the land at risk of water repellence (based on the extent of susceptible soils) as well as the degree of repellence. For NatureMaps, the standard legend categories have been simplified to a minor extent.
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. Water Repellence 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
AusGOALCC BY (Attribution)

Attributes

TableNameField AliasData TypeDescription
Landscape.SALAD_WaterRepellenceLANSLU CharacterSoil Landscape Map Unit.
Landscape.SALAD_WaterRepellenceWATERREPEL CharacterProportion of LAND SUSCEPTIBLE / DEGREE of water repellence (Legend category. See layer file for descriptions).
Landscape.SALAD_WaterRepellenceU1 NumberPercentage of map unit which is non-repellent.
Landscape.SALAD_WaterRepellenceU2 NumberPercentage of map unit which is repellent.
Landscape.SALAD_WaterRepellenceU3 NumberPercentage of map unit which is strongly repellent.
Landscape.SALAD_WaterRepellenceUX 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