Characterization, classification, and suitability evaluation of some soils in the floodplains of River Niger, Kogi East, Nigeria for rice, maize, cassava, and oil palm production

Abstract

This study was conducted to characterize, classify and evaluate four soils along River Niger in Kogi East for rice, maize, cassava and oil palm production. The soils developed predominantly from alluvium. The soils were located in four communities namely Ejule-Ojebe, Shintaku, Bagana and Kpata all in the floodplains of River Niger in Kogi East. The soils were investigated using a free survey technique. Four pedons representing four soils located at different sites in the floodplain were studied. The environs and the profiles of the soils were described according to standard field procedures. Soil samples were then taken from genetic horizons for laboratory analysis. The soils were also characterized and classified according to Soil Taxonomy and the World Reference Base for Soil Resources (WRB). The colour of the soils ranged from shades of brown to grey generally due to poor drainage. The soils also varied in depth and horizonation due to differences in profile development. Due to the relatively higher sand content of the soils, especially in the surface and subsurface horizons, the texture of the soils generally ranged from sand to clay loam. The pH (H₂O) of the soils ranged from 4.8 to 7.3, strongly acidic to slightly alkaline, and tended to increase with depth. The soils contained
moderate amounts of organic carbon in the surface soils but lower levels in the lower horizons. Based on their properties, the soils were classified according to Soil Taxonomy as Alfisols (Ejule-Ojebe), Entisols (Shintaku), Inceptisols (Bagana) and Alfisols (Kpata) and according to WRB as Planosols, Arenosols, Gleysols and Planosols, respectively. The soils were found to be highly suitable for rice production but moderately suitable for maize, cassava and oil palm. Apart from rice cultivation, wetness of soil was found to be the major limiting factor for optimum rainfed cultivation of maize, cassava and oil palm.