Abstract: The impact of dredging on the sediment quality of Igbedi Creek, upper Nun River in central Niger Delta was investigated from June 2009 to May 2011. Two locations – Ogobiri (Dredged Location) and Agoro-Gbene (Un-dredged Location) were studied. For the purpose of this study, the selected dredged and non-dredged sites were divided into stations: Ogobiri – OGO1DA=Dredged Area, OGOI&2DS=Downstream, OGO1&2US=Upstream; Agoro-gbene – AGO1DS=Downstream, AGO1MD=Midstream, AGO1US=Upstream. Physico-chemical characteristics of the sediment in both locations investigated includes:- particle size analysis (%silt, %sand & %clay), pH, available phosphate, nitrate, nitrite, total hydrocarbon (THC), %organic carbon, carbon/nitrogen (CN) ratio, total nitrogen (TN), sulphate, sodium, potassium, calcium and magnesium. The data revealed significant spatial differences (P<0.05) between the locations in all the sediment parameters measured except for Silt%, THC and CN Ratio. There were significant temporal variations between the locations for the following parameters: pH, TN, %Org.C, C/N Ratio, Mg, P042- and Na. The results also showed high increase in values recorded for THC, S042- and Ca in the station immediately downstream of the dredged area which steadily declined further downstream. The results obtained are indicative of impact of dredging on sediment quality of Iggedi creek, upper Nun River.
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