Abstract

F.O. Adekayode

The effects of land use on soil nutrient concentration and fertility were investigated in a research conducted in Akure (Latitude 70 18’12”N and Longitude 50 8’4”E) in 2013 using the GIS interpolation technique. The land use types identified on the GeoEye-1 satellite image were maize, cassava, oil palm and forested areas consisting of bush regrowth and uncleared forest. The feature extraction technique in Arc GIS was used to group and delineate the land use types while soil samples at seven locations were taken from each land use and analysed for nitrogen, phosphorus, potassium, calcium, magnesium and organic matter. The spatial nutrient concentration across the land use types was generated using the GIS kriging technique of 3D Analyst/Raster Interpolation/Kriging Tools while the fertility map was generated using the overlay operations of 3D/Raster Math Tools in ArcMap. The fertility map generated indicated high fertility status in the uncleared forest and oil palm while the greater portion of bush regrowth was of medium fertility and the portion of each of maize and cassava was of low soil fertility.