Effect of Altitudinal Gradient and Selected Land-use Systems on the Physicochemical Properties of Soils in the Eastern Flank of Mount Cameroon

The physicochemical properties of soils within the Mount Cameroon region are constantly changing due to their altitudinal gradient and diverse land-use systems. This modification poses a threat to the inhabitants of this area as their livelihood depends on these soils. Information about an impact of altitude and land-use systems on soil physicochemical properties in the eastern flank of Mount Cameroon is scanty and needs investigation. Soil samples, collected from different land-use systems along altitudinal gradients within the Buea zone (older lava flow) and Ekona zone (20th century lava flow), were analysed for their physicochemical properties using standard methods. The relationships among soil properties; altitude and land-use systems were established using correlation analysis and the analysis of variance (ANOVA). Sand and clay varied significantly (p<0.05) with altitude. Soils under mixed cropping with legumes had the highest pH values while those under mixed cropping without legumes had the lowest pH values. Calcium (Ca2+) and magnesium (Mg2+) dominated the exchange complex. Total nitrogen (N) and organic carbon (OC) ranged from 0.18 % and 1.50 %, respectively in soils under mixed cropping without legumes to 0.81 % and 6.55 %, respectively in soils under fallow land. There were significant (p<0.05) positive correlations between pH and Ca2+, pH and effective cation exchange capacity (ECEC), pH and moisture content (MC), and Ca2+ and MC. Soils from the Ekona zone located at the leeward side of the mountain and receiving more essential nutrients from the weathering of the young lava flow had a better-quality potential compared to soils from the Buea zone located at the foot of an older lava flow. The Ekona zone could be harnessed for extensive agricultural activities. Management practices should therefore take into account all cultural practices, which enrich soils for sustainable crop production and soil maintenance.