EVALUATION OF SOIL NUTRIENT AND FERTILIZATION PLAN OF CASSAVA FARM, NAOC (NIGERIANAGIP OIL COMPANY), OMOKU, RIVER STATE.

Abstract

The impact of oil exploration on soil fertility in Nigeria is hindering the efforts toward soil improvement. Crude oil induced pollution on soil environment is an increasing trend into the environment. There is the need to evaluate soil nutrient and fertilization plan for the cassava farm of NAOC (Nigerian AgipOil Company)in omoku, River State,Nigeria. Three cassava farms, largely cultivated was purposely chosen. Soil samples were taken from 0-30 cm depth at 12 meters intervals along transverses cut at 120 m apart. The samples were air-dried at room temperature, crushed and made to pass 2 mm sieve. Soil pH, organic matter (OM), total nitrogen (TN), available phosphorus (P), Exchange potassium (K), electric conductivity (EC) and Acidity (H + AI) were measured.The result obtained from soil in farm 1, 2 and 3 shows that the soil type is loamy (49%) silt (58%) and sandy (53%) respectively. soil from farm 1, has high OM (3.020) and total nitrogen (0.151%), low available P (11.00ppm) and K (70.00ppm), normal in EC (0.011 Ms/cm/), with a pH (6.4) partly salty and acidic. Farm 2 recorded low OM (1.590), TN (0.080%), P (12.00ppm) and K (90.00ppm) and normal EC (0.086 Ms/cm/), and a pH (6.2) partly salty and acidic. Soil from farm 3, was almost similar with farm 1, except having pH (6.600) neutral. It recorded high OM (3.090), high TN (0.155%), low P (10.00ppm), low K (66.00ppm) and normal EC (0.065 Ms/cm/). The fertilization status and plan for a standard application of NPK at 15:15:15 at the rate of 333kg/ha, at about 8 WAP, in a ring of about 10cm away from the cassava plant 6 cm deep required a fertilizer plan of 111kg of SSP/83kg MOP, 65kg of SSP/50kg MOP and 111kg of SSP/50kg MOP to meet up N and K recommended plan to farmer in the studyarea for farm 1, 2 and 3 respectively.