Norfolk Island soil permeability DSM attribute

Soil permeability 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 permeability indicates the rate of water movement into and through the soil and is described as defined by the National Committee on Soil and Terrain 2009 (NCST) soil permeability descriptions. This raster data represents a modelled dataset of soil permeability and is derived from field measured site data and environmental covariates. Data values are: 1 Moderately permeable, 2 Highly permeable. 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 permeability 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.

土壤渗透率(Soil permeability)是诺福克岛水资源评估（Norfolk Island Water Resource Assessment, NIWRA）项目下开展的数字土壤制图工作中所分析的九项土壤属性之一。之所以选取该属性，是因其对地下水补给、地表水储存以及人工含水层补给均具有关键意义。土壤渗透率指水分渗入并穿透土壤的速率，其分类标准遵循2009年土壤与地形国家委员会（National Committee on Soil and Terrain 2009, NCST）发布的土壤渗透率描述规范。本栅格数据为经建模得到的土壤渗透率数据集，数据源自野外实测场地数据与环境协变量。数据取值如下：1 中等渗透率，2 高渗透率。本数据集还附带一份反映数据可靠性的配套数据集，相关说明可查阅本元数据记录的数据谱系章节。数据处理通过R语言的ranger扩展包完成，土壤属性建模采用随机森林(Random Forest)方法。更多关于土壤渗透率的详细信息可参阅NIWRA技术报告（Petheram等，2020）。数字土壤制图(Digital Soil Mapping, DSM)流程详见NIWRA技术报告的附录E。