Norfolk Island soil drainage DSM attribute

Soil drainage is one of nine soil attributes analysed as one component of a digital soil mapping exercise undertaken as part of the Norfolk Island Water Resource Assessment (NIWRA). It was selected due to its importance to groundwater recharge, surface water storage and managed aquifer recharge. Soil drainage indicates the rate of water movement laterally and downward from the profile and is described as defined by the National Committee on Soil and Terrain 2009 (NCST) soil drainage descriptions. This raster data represents a modelled dataset of soil drainage and is derived from field measured site data and environmental covariates. Data values are: 1 Poorly drained, 2 Moderately well drained, 3 Well drained, 4 Rapidly drained. A companion dataset presenting reliability of this data is also provided and can be found described in the lineage section of this metadata record. Processing was carried out in the ranger package inside R and attributes were modelled using a Random Forest approach. Further soil drainage information can be found in the NIWRA technical report (Petheram et al., 2020). The DSM process is described in Appendix E of the NIWRA technical report.