Dataset Number 1079 Dataset Title Alkalinity Custodian Data Authority: Department for Environment and Water Data Provider: Department for Environment and Water

Description Description Soil pH is alkaline when there is an excess of negatively charged hydroxyl ions in the solution of a soil layer. Alkaline soils (generally confined to <400 mm annual rainfall areas) can cause problems for plant growth due to reduced availability of phosphorous and essential trace elements (zinc, manganese, iron). This effect becomes more pronounced as the proportion of fine carbonate particles increases. Plant species and varieties have varying tolerance to alkaline conditions. Soils made alkaline by calcium carbonate alone rarely have pH >8.3 (in water). Where fine calcium carbonate is present in the soil matrix these soils are termed 'calcareous'. Alkaline soils with pH >8.3 usually have significant exchangeable sodium (sodic soils) or carbonates and bicarbonates of sodium. The alkalinity of each component of each Soil Landscape Map Unit (LANSLU) is assessed. All land that is known to be alkaline, or is similar to land known to be alkaline, is classified accordingly. Eight Alkalinity attribute (or 'analysis data') classes have been supplied (see I1_1, I1_2, etc in table below, including not applicable) as percentage (areal extent) values of each LANSLU. Note: the sum of all percentage values for each map unit totals 100%. The analysis data is to be used for the calculation of spatial data statistics. Alkalinity attribute classes account for both surface (0-10cm) and subsoil (30-80cm) alkalinity. Respective pH values for soil alkalinity classes are: 'Strongly alkaline': pHCaCl2 >8.5 or pHH2O >9.2SELECT 1 FROM DUAL; 'Alkaline': pHCaCl2 7.0-8.5 or pHH2O 8.0-9.2SELECT 1 FROM DUAL; 'Non-alkaline': pHCaCl2 <7.0 or pHH2O <8.0. For map display purposes, LANSLUs are categorised INTO 9 legend categories (ALKALINE), including not applicable, designed to highlight the component(s) exhibiting the highest, most limiting alkalinity class, provided this accounts for at least 30% of the map unit. Map units with limited occurrences of alkaline soils (10-30% of area) are shown as an additional legend category. Usage Link 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. Alkalinity dataset can be viewed at NatureMaps (>Soils>Soil Chemistry Attributes). Spatial data downloads are available from Data SA.

Data Quality Lineage The 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. Completeness Complete. The spatial data is subject to amendment as and when more data become available. Positional Accuracy The 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 are to be used at the regional, subregional and catchment-level, and can be used to provide property overviewsSELECT 1 FROM DUAL; however, they cannot to 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.

Geographic Extent Extent Name Agricultural Region - South Australia Min Easting or Longitude 132.25 Min Northing or Latitude -38 Max Easting or Longitude 141 Max Northing or Latitude -32.25

Dataset Status Initially Acquired 01-JAN-2000 Last Updated 01-JUL-2009 Update Frequency As required Maintenance Method As required AusGOAL CC BY (Attribution)

Attributes

Contact Information Organisation Department for Environment and Water Science Monitoring and Knowledge Postal Address GPO Box 1047 ADELAIDE 5001 Email DEWNR.CustomerServiceCentre@sa.gov.au