[01] Ogbuagu Dike Henry, Department of Environmental Technology, Federal University of Technology, Owerri, Nigeria. [02] Ogoke Fidelis Chukwuma, Department of Environmental Technology, Federal University of Technology, Owerri, Nigeria. [03] Mbuka-Nwosu Iheoma Ezichi, Department of Environmental Technology, Federal University of Technology, Owerri, Nigeria.

The role played by oxygen in the degradation of nutrients (NO₃^-, PO₄^3- and SO₄^2-) in sediments of the Bonny Estuary, which is repository to pollutants arising from various industrial and shipment activities in its catchment was investigated. Sediment samples were monitored under aerobic and anaerobic conditions for nutrient fluxes. Harvests and spectrophotometric analyses were made on Days 0, 14, 28 and 42. NO₃^- ion concentrations degraded from 10.21 to 2.72ppm in aerobic and 10.21 to 3.08ppm in anaerobic condition; PO₄^3- ions degraded from 122.6 to 92.5ppm in aerobic, and 122.6 to 102.2ppm in anaerobic conditions; while SO₄^2- ions degraded from 128.4 to 108.2ppm in aerobic, and 128.4 to 118.2ppm in anaerobic conditions. The degradations of PO₄^3- and SO₄^2- ions, as well as changes in pH differed significantly over the 42 days experimental period in both aerobic (Sig. F=0.000 each) and anaerobic conditions (Sig. F=0.003, 0.000 and 0.000 respectively) at p<0.05. There were also significant differences between degradations in aerobic and anaerobic conditions at the 95% confidence limit. Degradation was steady and the nutrients fluxes were oxygen- and time-dependent.

Bonny Estuary, Nutrients Fluxes, Aerobic Condition, Anaerobic Condition, Sediments, Degradation

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