Soil colors as indicators of soil quality in soils formed over coastal plain sands of Owerri agricultural area, southeastern Nigeria

Abstract

The study investigated soil chemical properties associated with three different soil colors, namely Dark reddish brown (5YR3/2) moist, Reddish brown (5YR4/4) moist and Light reddish brown (5YR) moist. Dark reddish brown soils were slightly acidic (pH 6.1) while reddish brown and light reddish brown colors were moderately acidic (pH = 5.0) and strongly acidic (pH= 4.5) respectively. Effective cation exchange capacity (ECEC) was highest in dark reddish brown soils (7.2 cmol/kg), followed by reddish brown soils (6.2 cmol/kg), while 5.5 cmol/kg was recorded on light reddish brown soils. Value of total carbon was highest in dark reddish brown (2.0%), while reddish brown and light reddish brown soils had 1.2 and 0.7% respectively. Soil pH varied with color with dark reddish brown giving a coefficient of variation (CV) of 10%, reddish brown, CV of 31% and light reddish brown CV of 55%. Variability was indicated in total carbon with dark reddish brown having CV = 40%, reddish brown CV = 24% and light reddish brown CV = 12%. Soil color could be used as reliable indicator of soil quality in the tropical humid rainforest area of Owerri, Southeastern Nigeria.

International Journal of Natural and Applied Sciences Vol. 1(2) 2005: 118-121