A study of soil factors in relation to erosion and yield of maize on a Nigerian soil

Abstract

The study aimed at quantifying the effects of erosion on the productivity of a Nigerian soil involved the use of a half hectare farmland with history of various degrees of erosion severity. The farmland was divided into 3 different classes; class I (uneroded), class II (slightly eroded) and class III (moderately eroded) based on the degree of erosion severity and were then planted with maize. The mean topsoil's (0–15 cm) colour hue reduced from 7.5YR on class I to 5YR on class III soils (representing colour change from dark brown to dark reddish brown) on Munsell's colour chart. The soil properties and the maize yield on the farmland exhibited strong spatial variability, the trend of which appears to have been influenced by the topography of the area. The mean yield on the class II plots and the class III plots were 80% and 65% respectively of that in class I plots. Because of the strong functional dependencies identified among many of the variables, multivariate statistical procedure was used to identify the variables that influence maize yield. Seven components were selected based on factor analysis. These components when regressed against maize yield, were found to explain 95% of the variability in maize yield. The yield of maize on this soil was found to be determined by soil properties such as; bulk density, organic carbon, topsoil thickness, texture, pH and gravel content in the topsoil, and by base saturation, organic carbon and exchangeable acidity in the subsoil.