Ionic Mobility of Cations as Affected by Redox Status of Two Different Soil Textures

Movement of ions within the soil plays a key role in nutrient availability as well as soil management. Various reactions in the soil contribute to soil ionic mobility and consequently nutrient availability, one of which is the oxidation-reduction reaction. Hence, this study sets out to evaluate the effect of redox status of the soil on ionic mobility of cations. A 3x2x2 factorial experiment was set up on two different soil types (clay loam and sandy clay loam), arranged in a Randomzed complete Block design (RCBD) with three replicates. The treatment combination involved three levels of poultry manure (0 tha-1, 6 tha-1 and 8 tha-1), two levels of NPK 15-15-15 (0 gha-1, 200 kgha-1) and two water regimes (field capacity and waterlogging). Twelve treatments were obtained giving rise to different redox potential. Redox potential was measured using a redox meter, electrical conductivity using a conductivity meter; Ionic mobility was calculated using the mobility equation. Results from this study show that ionic mobility was highest under highly reduced conditions, also ionic mobility was highest in sandy clay loam than clayey loam and potassium ion has the highest mobility while magnesium has the lowest mobility. It was concluded that soils can be subjected to reduction process to increase the mobility of cations hence there availability to plant. However care must be taken to avoid the loss of highly mobile ions like potassium.