Abstract

Vertisols are widespread in North Cameroon, but are undercultivated due to difficulties linked to their shrink-swell behaviour under different moisture conditions. Eighteen vertisol samples from five profiles representative of the studied area (Benue floodplain in North Cameroon) were studied to establish a relationship between moisture and physico-chemical characteristics and supplement data for planning sustainable agricultural management. The main results revealed that the soils are deep, dark grey, heavy clayey, with high coefficients of linear extensivity, low organic matter and low electrical conductivity. At field capacity, they showed a very low bulk density, high porosity and a high void ratio. Oven-dry soils exhibited very high bulk density, very low porosity and very low void ratio. This high reversibility of properties with changing moisture content is related to high smectitic mineralogy. The moisture properties revealed very high water-holding capacity, very high available water and very high readily available water. Most of the physico-chemical characteristics correlated well with the moisture parameters. The principal component analysis revealed a reduction of 17 initial variables to two principal components (PC1 and PC2) explaining over 70% of the total variance. The PC1 clustered 12 soil and soil moisture variables indicating strong correlation between moisture and physicochemical properties. Management practices for crop production must be primarily directed at moisture control.

Key words:  Vertisols, soil moisture, soil suction, land evaluation, Benue floodplain.