Soil and Their Agronomic Suitability for Cocoa (<i>Theobroma</i><i> </i><i>cocoa</i><i> </i><i>L.)</i> in South Cameroon Plateau

Cameroon is the world's fifth largest producer of cocoa (40,000 hectares of land), which is the main cash crop, employing 75% of farmers in central and southern Cameroon. However, low yields (370 kg. ha-1) have been observed over time due to soil conditions, climate variability, and poor agricultural practices. To this end, a detailed characterization of the soils of the southern Cameroonian plateau will make it possible to optimize yields. Thus, the present study aims to characterize the soils of the Nkolandom locality in order to determine their suitability for cocoa cultivation. The study consisted of conducting a soil survey to open pits, whose horizons were characterized, and samples were taken for laboratory analysis of physicochemical parameters. The evaluation of the suitability of the soil for cocoa cultivation was carried out using the FAO method. Three (03) types of soil were identified: loose soils, hydromorphic soils, and soils on crust, which have morphological and analytical characteristics such as thick, sandy-clay to clayey texture, polyhedral structure, acidic to very acidic pH (4.1 to 5.8), low to moderate CEC content (7.28 to 27.76 cmol kg-1), and low to very high organic matter content (1.4 to 9.1%). These soils have respective suitability classes S3/Nc,f , Nc,w and Nc,s due to climatic limitations, soil fertility, soil water conditions and soil physical characteristics. Ferrasols have a marginal to unsuitable aptitude due to climate (relative humidity in the driest month), where it is advisable to irrigate the soil in the dry season and use agroforestry systems (SAF), and soil fertility (pH and CEC), where it is more appropriate to correct the soil pH and use cover cropping systems (SCV). Gleysols and Ferrasols on armourstone have an uncorrectable inaptitude due to the waterlogging of these soils and the presence of armourstone where cocoa cannot move its roots well.