A Comparative Study of Physicochemical Characteristics of Sediments of Azuabie and Obufe Creeks in the Upper Bonny Estuary, Niger Delta

Abstract

Physico-chemical parameters in sediment of the Azuabie and Obufe Creeks were monitored from February 2021 – January 2022. Nine sampling stations (five in Azuabie and four in Obufe) were established along the Creeks based on sources of industrial and human pollutant inputs. Sediment samples were collected with an Eckman grab. Some parameters (pH, Redox Potential and Conductivity) were analyzed in situ using a multiparameter water quality meter (Hanna H19829), while appropriate standard methods were used for total hydrocarbon content (THC), total organic content (TOC), ammonium-nitrogen, nitrate and phosphate in the laboratory. The mean pH in Azuabie Creek was 7.12 (±0.74) while that in Obufe Creek was 7.16 (±0.73). Mean ±SD values for other parameters are as follows: Redox potential in Azuabie Creek (46.05±26.28 mV), Obufe Creek (34.98±19.05 mV).; Conductivity in Azubie Creek (2696±1434), Objufe Creek (2662±1536). THC) in Azuabie (100.40±236.56), Obufe (69.29±196.91) Creek. TOC in Azuabie Creek (4.28±± 1.12), Obufe Creek (3.35±1.63); Ammonium-Nitrogen Azuabie (0.06±0.03 mg/kg) and Obufe (0.08±0.06 mg/kg). Nitrate in Azuabie Creek was 0.22±0.10 mg/kg while that in Obufe Creek was 0.26±0.12 mg/kg; Mean phosphate values in Azubie Creek (0.40±0.78), of Objufe Creek (0.26±0.09). Student’s t-tests showed that mean values of pH, Conductivity, THC, nitrate, and phosphate were not significantly different between Creeks. However, Redox Potential and TOC were significantly higher in Azuabie Creek, while ammonium-Nitrogen was significantly higher in Obufe Creek. The THC values in both creeks were higher than the EGASPIN target value of 50mg/kg and are a cause for concern.

Keywords

References