Effect of NPK fertilizer and interval management on the chemical properties of coastal plain sands of Akpabuyo, Nigeria

Au Akpanidiok,W Ubi,Mw Ubi

doi:10.4314/gjass.v12i1.10

Abstract

Investigation of the chemical properties of the coastal plain soils treated with NPK 20:10:10 fertilizer (NPK) at the rate of 0,60, 90 and 120kg ha-1) and observed at intervals of 3,6,9 and 12 months was carried out from March 2009 to 2010 at Akpabuyo, Cross River State, Nigeria. The experiment comprises of four fertilizer rates and four management intervals fitted into a Latin square design. The soils pH value increased consistently from 3 to 12months. Mean values of organic matter decreased with increase in profile depth from 2.12-1.34g kg-1). The distribution of N from the top soil down the profile increased consistently from 3 to 12 months. The mean value of N from the top soil was 0.82%. Exceeding 0.2%, the critical value and was more than the mean values obtained in the sub-surface soil. The mean value of P (33 mgkg-1)) during the 9 months interval was significantly (P<0.05) higher than all other samplingperiods. There was vertical and horizontal loading of P which lead to higher available P at the surface in soil depths of 0-15 and 15-30cm than 30-40cm and 40- 50cm. Levels of Ca increased slightly with sampling interval but decreased down the profile. The soils were also characterized as follows: strongly acid (pH 5.1 – 5.3), exchangeable Mg. (> 0.5cmol kg-1)), low contents of K and Na as well as high exchangeable Al. levels (> 4.0 cmol kg-1)) and cation exchange capacity (22 – 36 cmol kg-1)) The application of 90 kg/ha-1) NPK fertilizer during the 9 months interval gave highest values of N.P, Ca and Mg under the condition of the experiment, indicating that these elements will not be deficient in these soils. Equally, the CEC, organic matter and base saturation had their advantage in the 9 months interval where 90 kg'' was applied. This is cost effective and could be used to improve crop production in Akpabuyo, Nigeria.KEY WORD: Chemical Properties, NPK Fertilization, Management Intervals, Coastal Plain Sands.

Highlights

To increase crop performance, there is always need to establish relationships between soil chemical properties and soil capacity to produce food crops
Yield and crop performances are closely correlated with soil condition
Soil Reaction Soil reaction varied from mildly acid to medium with mean pH values of 5.1 at 3 months, 5.1 at 6 months, 5.7 at 9 months and 5.9 at 12 months

Summary

Introduction

There is always need to establish relationships between soil chemical properties and soil capacity to produce food crops. The soils capacity and capability to produce crops is the basis of yield predictions and could be considered as the most useful expression of soil productivity (Enwesor, 1981). Yield and crop performances are closely correlated with soil condition. FAO (1986) reported that coastal plain sands cover an area of 480km in Cross River, 3,470.32km in Bendel State, 42.20km in Lagos State, 213.16km inAkwa Ibom State, 12.18km in Ogun State, 40.62km in Ondo State; and 5.435.92km in River State. In Cross River State, coastal plain soils are found mostly in Akpbuayo, Bakassi, Calabar and Odukpani Local Government Areas. In crop production and land use, the evaluation of soils’ chemical properties is important because properties such as pH, Organic matter, Nitrogen, Phosphorus

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