The microbial profile of some concrete and earthen fish ponds within the Niger delta region was evaluated. The results of physico-chemical properties of the water samples showed that alkalinity values were significantly higher in concrete ponds (99.7±47.1 to 150±69.7) than (18±6.9 to 24±14.5 mg/L) in earthen ponds. Electrical conductivity values varied significantly between the ponds with (200±84.1 to 290±74.9 µs/m) in concrete ponds and (18±6.9 to 24±14.5 µs/m) in earthen ponds. Sulphate concentrations were higher in concrete ponds (0.25±0.36 to 1.53±14.9 mg/L) than (0.25±0.36 to 0.4±0.77 mg/L) in earthen ponds. The mean total heterotrophic bacteria count was higher in concrete ponds (6.5×10 5 to 7.4×10 5 cfu/ml) than in earthen (6.3×10 5 to 6.5x10 5 cfu/ml) ponds. The mean fungal count ranged from 2.11×10 5 to 2.25×10 5 cfu/ml in concrete pond and (1.8×10 5 to 2.4×10 5 cfu/ml) in earthen ponds. The bacterial genera isolated from the ponds were Escherichia coli, Staphylococcus sp., Aeromonas sp., Streptococcus sp., Salmonella sp., Vibrio sp., Shigella sp., Proteus sp., Pseudomonas sp., Klebsiella sp. Enterobacter species occurred only in concrete pond, while Serratia species occurred in earthen ponds. The fungal genera isolated from both the concrete and earthen ponds were Aspergillus sp., Penicillum sp. and Cladosporium sp. The genera, Fusarium sp. and Mucor sp were isolated only from earthen ponds. The study revealed that the ponds were grossly contaminated with pathogenic microorganisms which poses a risk to human health, thus of significant public health concern.

Laboratory-scale studies were carried out using a nutrient formula produced from Eicchornia crassipes plant to achieve bioremediation of crude oil impacted mangrove soil. In a 70 day study, the culturable heterotrophic bacterial population of the Eichhornia crassipes recipe increased from 6.26×105 Cfu/g to 2.69×10 7 Cfu/g. The control set-up had its total culturable bacterial count increased from 5.76×10 5 Cfu/g to 1.24×10 6 Cfu/g. Statistical analyses showed significant difference for the two conditions (p ≥ 0.05). The total culturable heterotrophic fungal count in the Eichhornia crassipes recipe treatment increased from 5.36×105 Cfu/g to 2.50×10 7 Cfu/g respectively. The total culturable hydrocarbon utilising bacteria in Eichhornia crassipes treated polluted mangrove soil increased from 2.52×104 Cfu/g to 3.81×10 7 Cfu/g. Statistical analyses showed significant difference at p ≥ 0.05 level for the two conditions (Eicchornia crassipes nutrient treated soil and control). The total culturable hydrocarbon utilising fungal counts increased significantly for both the control and Eichhornia crassipes treatment. There was no regular trend in pH changes in all the conditions. The conductivity value of the Eichhornia crassipes recipe treated soil decreased progressively. Phosphate, nitrate, %total organic carbon, Total Hydrocarbon Content (THC). Studies using Gas chromatographic analyses showed that in the Eichhornia crassipes recipe treated polluted mangrove soil, 0, 58.92 and 75.36% were lost at zero hour, 28th day and 70th day respectively. In addition, in the control experimental set-up, 0, 7.14 and 13.42% of TPH were lost at zero hour, 28th day and 70th day respectively. There was no significant difference between the control experiment and Eichhornia crassipes (p = 0.054). The use of organic nutrient sources such Eichhornia crassipes recipe/nutrient powder is of good use as source of limiting nutrient needed for bioremediation of crude oil impacted medium.

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Aims: To determine the antibiotic susceptibility profile of bacterial isolates from concrete and earthen fish ponds. Study Design: Comparative analysis.

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