Relationship of Landscape Positions with Soil Properties on Maize Yield in Ultisol

Abstract

Relationship of landscape position and soil properties to maize (Zea mays L.) yield was studied in coastal plain soils of Akwa Ibom state. The study aimed at assessing the physico-chemical soil attributes down the geomorphic surface as well as assessing the yield of maize in the respective landscape positions. A total of 3600 plant population (hybrid maize) were planted on 0.072ha in a Randomized complete block design. The traditional land preparation technique was employed with slashing of regrowth vegetation with cutlass. The trashes was left on the sites and allowed to dry for three weeks. Preburn soil samples were taken before burning the trashes at the end of three weeks after slashing. The samples collected were analyzed in the laboratory for physico-chemical properties using standard methods. Collected data were statistically analyzed and means of statistically significant parameters were separated using LSD (0.05). The results showed that sand particle of burnt and un-burnt soils were significantly different at 0-15cm of Upper slope (US) but not significantly different in other landscape positions (p<0.05). Soil pH in burnt soil was significantly different from the un-burnt soil (both at surface and sub surface) in the three landscape positions. Mean maize yields (with husk) was 0.09 and 0.11kg/ha before and after burning plots of US ; 0.12 and 0.16kg/ha in before and after burning plot of the middle Slope (MS) while the Bottom valley (BV) had 0.14 and 0.16kg/ha in before and after burning plots. Altogether, both husked and de-husked yields were higher in burnt plots than unburnt plots. Along the slope, husked yield followed the order: BV (0.15kg/ha) > MS (0.14kg/ha) > UP (0.10kg/ha)) while de-husked yield also followed similar pattern but different magnitude.