Assessment of GIS-interpolation techniques for groundwater evaluation : a case study of the Sandveld, Western Cape, South Africa

[摘要] ENGLISH ABSTRACT: The Sandveld, a potato growing area of the Western Cape is subject to significantgroundwater abstraction for both municipal and agriculture purposes. The climate is arid andsensitive and important ecosystems in the area are showing varying degrees of impact.Management measures are needed to ensure ongoing sustainable development of the area.In this study, different interpolation techniques were evaluated to calculate values forunsampled variables rainfall and groundwater elevation. Local deterministic techniques aswell as geostatistical techniques were used. It was found that geostatistical techniques,especially with collateral information, such as topography, provided a more accurate result.For environmental studies of this nature, Kriging is recommended as interpolation technique.The underlying data will determine the selection of the particular type of Kriging.Data was extracted from a customized relational database, geoMon, used for data capture,retrieval, processing and reporting. Ease of data extraction facilitated analysis.The interpolated grids were applied in two scenarios: Recharge calculations and quantificationas well as a new classification approach according to Resource Directed Measures (RDM).Management classes were defined based on GIS-derived data.

[发布机构] Stellenbosch University