AN ASSESSMENT OF THE EFFECT OF SOIL DEGRADATION ON SOILS OF LAPAI AREA, NIGER STATE, NIGERIA.

Aminu, Z.*, Ishaku, B. and Yakubu, M.

The research was carried out to assess the effect of soil degradation on soils of Lapai area. One hundred samples comprising of four sub-samples taken from five different land uses (plantation, ‘fadama’, cultivated, scrubland and badland) were analysed for key soil properties. Descriptive statistics were used to summarise the data while Analysis of variance and student t-test were used to analyse the data. The particle size distribution tests show that sand fractions in the soils are higher over scrubland at 77.3% and least over ‘fadama’ (51%). The highest bulk density value is in badland (1.62g/cm³) and least over plantation (1.37 g/cm³). Results also show that soil pH is highest over plantation(6.51) and lowest over badland (5.40). The analysis of variance for Ca shows that significant difference exist at 0.05 level in the respective landuses. Mean value of total nitrogen is highest in the plantation (0.79%) and least over bad land (0.23%). Comparison of results to critical values of soil fertility ratings show that soils in the study area have undergone degradation resulting to higher bulk densities, lower porosity, lower soil moisture contents, low organic matter content, higher pH values and low CEC values of soils, particularly over badland and cultivated landuses. Recommendations include formulating policies which eliminate discriminatory land ownership rights, rehabilitation of degraded lands and encouraging sustainable soil management practices such as tree planting, mulching, fallowing and intercropping.

Key words: Analysis, Degradation, Indicators, Landuse, Soil.