Abstract: Understanding topographic surfaces and features is critical to providing ecological explanations for numerous consequences of human-environment interactions. However, there is a lack of regional information about the Nigerian environment, probably because topographic analysis often requires lengthy fieldwork. New advances in geographic information systems and remote sensing also point to the need to introduce publicly available open-access data and simplified procedures. This study is a simplified analysis of digital elevation models (DEM) from the open access records of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER Global DEM) and the Shuttle Radar Topography Mission (SRTM). The main objective was to compare the slope, aspect, elevation, and topographic index of some selected topographic features in Ife Central Local Government Area of Osun State, Nigeria. Using ArcGIS software, the DEMs for the same period were extracted from the ASTER and SRTM data and were compared. The results showed comparative qualitative differences in the extracted forms of drainage properties, topographic index, and slope aspect, but did not show that the values were statistically different at the 95% confidence level. The study concluded that the DEMs, have differences that, if not thoroughly examined, can lead to inaccurate, erroneous, or incomplete results. Further research is recommended on quality control and comparative quality evaluation of widely used remote sensing products from missions whose ground controls are located outside of the nation.
Key words: Digital elevation models, Medium-size settlements, Remote sensing, Topographic analysis