Abstract

In the last decade, the quantitative models for digital mapping of soils have experienced rapid development of new methods, more efficient and economic. One reason is due, mainly, to the increase of auxiliary information of physical environment, especially, the images from remote sensing and terrain attributes derived from digital elevation models. Thus, this study aimed to evaluate the quality of digital elevation models obtained by contour lines and from SRTM/Topodata resample to 30 m for digital soil mapping. Both digital elevation models were assessed for vertical quality and the potential to derive terrain attributes which captured the main processes that occurred in the area. To enable comparison, all digital elevation models were generated with a 30 m spatial resolution. The SRTM/Topodata and Digital Elevation Models (DEM) tends to underestimate elevation in peaks and ridges, and at this fine scale, the 1:10,000 cartography contour lines produce a more accurate and more detailed DEM. However, due to the size of Brazil in a lack of soils maps with good scale, the availability and spatial coverage of the SRTM/Topodata make it a desirable option.

Keywords: Digital elevation models, digital soil mapping, geographic information system.