Soil Mapping and in - Situ Soil Description of Selected Land Area of Funtua, Nigeria

The study was done to delineate soil mapping units and produce the soil map of a selected 10 000 ha land. Landsat imagery of the study area was acquired and used for land cover and land use identification. Digital Elevation Models (DEM) of 10 m resolution was also obtained to produce landforms and contour maps. A 10 000 ha land was delineated from the landform map and divided with grids at 400 m interval from which a base map was produced at a scale of 1:20,000. The maps were digitized and geo-referenced. The base map with grids was uploaded into a geographical positioning system (GPS) for detailed fieldwork. The detailed fieldwork identified six major soil mapping units, namely FT1, FT2, FT3, FT4, FT5, and FT6. In each soil mapping unit (excluding FT6), two soil profile pits were dug, described and sampled. Evaluation of the soil mapping units indicates FT1 covered 1755.17 ha (17.55 %) and occupied level (0 – 2 %) lower slope position and was very deep (> 150 cm) and well-drained. The FT2 occupied 6407.90 ha (64.08 %), was imperfectly drained and deep (100 – 150 cm) and was situated on nearly level (0 – 2 %) to gently sloping ground on mid-slope to lower slope position. The FT3 was deep (100 – 150 cm), very poorly to poorly drained, covered 636.60 ha (6.37 %) situated on gently sloping (2 – 4 %) ground on lower slope. The FT4 soils span through the crest to lower slope positions, shallow (25 - 50 cm), well-drained and occupied 708.70 ha (7.09 %) and FT5 occupied 175.60 ha (1.76 %) located on a nearly level to gently sloping crest to mid-slope positions. The FT5 soils were well-drained and had moderate depth of soil materials (50 - 100 cm). The FT6 was very shallow soils to rock outcrops, occupied 316.03 ha (3.16), and no profile pit was sunk to characterize the map unit.