Utilisation des données pour l\'évaluation de l\'hétérogénéité des sols ferrallitiques par la couleur selon le code Munsell

Abstract

Soil heterogeneity is known to seriously hamper fertility management and causes concerns in agronomic trials. Soil characterization trough factors, which spatial variability is well established, could be an option. Therefore, the Munsell chart (TSL) of soils was evaluated through the description the heterogeneity of one thousand twenty-height ferrallitic soil samples from the area above the 7th parallel. Particle size, soil C, total P total N and Ca, as well as exchangeable bases (S), effective cation exchange capacity (ECC) and base saturation (V) were assessed in relation with soil TSL, bed rock characteristics (Rm) and soil depth. Principal components and variance analysis were used to analyse data. Results show that the 5YR and 7.5YR soil samples from the surface horizons showed more heterogeneity than those of 2.5YR and 10YR, regardless of soil depth. Moreover, a reduction of soil physical and chemical heterogeneities, according to soil hue, depth and bedrock, was demonstrated. This study allows ferrallitic soil heterogeneity characterization by its colour.