SOIL PROPERTIES OF TERMITE MOUNDS UNDER DIFFERENT LAND USES IN A TYPIC KANDIUDULT OF SOUTHERN CAMEROON

The effect of land use, i.e. 3-4 years of cropping, 2- to 3-year-old Chromolaena odorata fallow and 10- to 15-year-old secondary forest, on soil properties of Microtermes termite mounds in Typic Kandiudults was studied in the humid forest zone of southern Cameroon from November 1990 to March 1991. Termite mound populations increased in the following order. secondary forest greater than fallow greater than cropping. Soil sampled from mound surfaces, mound perimeters (interface of mound and surrounding soil) and surrounding soil was analyzed for various physical and chemical features. Sand and clay contents of soil sampled from the surrounding soil and mound surfaces were primarily influenced by sampling location. The surrounding soil and that from mound surfaces consisted of 58.5% and 39.9% sand, respectively, and 25.6% and 47.9% clay, respectively. Particle size distribution in mound perimeters was, however, dependent on land use. With respect to other soil properties measured, both absolute values and spatial variation between sampling locations were, in general, primarily affected by land use. Bulk density particle size distribution, soil water retention at potentials less than or equal to -4.8 kPa, organic C, total N, pH, exchangeable cations (except total acidity) and effective cation-exchange capacity contributed significantly to the interactions in spatial variation between sampling locations and land uses.