Spatial Variation of Soil Moisture Content and Total Porosity As Influenced by Land Use Types in Lafia, North Central Nigeria

The study was carried out to evaluate the spatial variaility of soil moisture content and total porosity as influenced by land use, in Faculty of Agriculture, teaching and Research farm, Shabu, Lafia. A total of 81observations and samples were collected at every 10m along the Xaxis and 10m apart along the Y-axis and soil moisture content of the samples was determined gravimetrically, while total porosity was calculated using bulk density from gravimetric measurement. Spatial analyses of the physical properties were done in a GIS environment. Geo-statistical procedure (Mvariogram) of Genstat Package was used to determine and select appropriate spatial models for all the data set. Win- Surfer Version 7.0 (Golden Software Inc, Golden, Colorado) was used for interpolation technique called “Ordinary Kriging“ to produce the spatial distribution of soil moisture content and total porosity. The results showed that soil moisture content was negatively skewed but positive kurtosis, while kurtosis and skewness values in soil total porosity were both positive . This implies that both, tested parameters were highly variable and were not normally distributed. Anisotropy was not evident in the directional semivariograms for any of the properties. Therefore, isotropic models were fitted. Relative Nugget Effect (RNE) (The nugget-to-sill ratio (Co/Co + C)) of total porosity was 50% and 2.3% for moisture content. Contour Isoline mapping showed that the surface soil physical properties varied between the experimental plots as determined by land use type and management practices, plots with soil amendments having higher but highly varied surface soil moisture and better porosity. The results of this study demonstrated the need for Site-specific management as required in Precision Agriculture.