Assessment of Soil Fertility Status Using Nutrient Index Approach of Ovu Sub-Clan, Delta State, Nigeria

Abstract

Background: Amendment of soil fertility through regular nutrient assessment is a necessary intervention for sustainable crop production. Ovu, is a sub-clan in Delta State, Nigeria which comprised of: Ovu-Inland, Okoemaka, Ekpan, Urhodo, Okoroke and Oviorie that are mostly farmers without the knowledge of their soil fertility. The study investigated soil fertility status of Ovu Sub-Clan. Methods: Cassava, oil palm and plantain farms were randomly selected in the six community and 118 representative soil samples were taken. Soil pH, organic carbon, total nitrogen, available phosphorus content of soil and exchangeable bases were measured. Data were analyzed with descriptive statistics and Parker’s nutrient index was used to compare the fertility level. Result: The cassava, oil palm and plantain farms were slightly acidic mean values of 6.4±0.38, 6.5±0.31 and 6.4±0.30, respectively indicating slight acidity. Organic carbon was low to high while total nitrogen was high except at Okoemaka that was moderate (0.19±0.04%). Available phosphorus content was low to medium while exchangeable potassium and calcium were medium to high, exchangeable magnesium was low to medium. Nutrient index showed that soil pH was moderate and while total nitrogen was high.