EVALUATION OF AGGREGATE STABILITY AND HYDRAULIC CONDUCTIVITY OF SOILS DERIVED FROM DIFFERENT PARENT MATERIALS IN AKWA IBOM STATE, SOUTH SOUTH NIGERIA

This study was conducted to evaluate aggregate stability and hydraulic conductivity ofsoils derived from freshwater alluvium (FWA), coastal plain sand (CPS) and sandstone(SDS) in Akwa Ibom State, South-South Nigeria. Seventy-two core and composite soilsamples obtained at 0 – 20 cm and 20 – 40 cm depths from six locations representing theparent materials were analyzed by standard methods to determine their physical/ chemicalproperties, mean weight diameter (MWD), microaggregate stability and Ksat. Resultsshowed FWA/SDS soils were sandy loam and sandy clay loam, while CPS soils wereloamy sand and sandy loam at 0 – 20 cm and 20 – 40 cm depths respectively. Bulk densities3(1.42 – 1.58 g/cm ) were all low; organic matter (1.21 – 1.99%) was low in CPS/SDS soils,but high (3.10 – 4.02%) in FWA soils. Average MWD values for FWA, SDS and CPS soilsat 0 – 20 cm sampling depth were 0.349, 0.184 and 0.180 mm; whereas they were 0.288,0.221 and 0.271 mm at 20 – 40 cm depth respectively. Average clay dispersion ratios forFWA, CPS and SDS soils at 0 – 20 cm depth were 27.97, 28.51 and 29.16%; whereas theywere 26.13, 26.95 and 28.19% at 20 – 40 cm depth respectively. Average Ksat values forFWA, CPS and SDS soils at 0 – 20 cm depth were 25.27, 30.49 and 26.01 cm/hr; whereasthey were 16.36, 17.50 and 16.94 cm/hr at 0 - 40 cm depth respectively. Regularapplications of manure and adoption of other conservation measures were recommended.