DIVERSITY OF THE BACTERIAL COMMUNITIES OF THREE SELECTED STREAMS IN ANAMBRA STATE, NIGERIA.

Abstract

ABSTRACT The bacterial community structure of Mgbakwu, Obibia, and Urum streams in Akwa North and South Local Government Areas, Anambra State, Nigeria, using biodiversity indices, was assessed. Standard protocols were followed in the collection and bacteriological analysis of water samples. The bacterial community structures were studied using richness, evenness, and diversity indices. The bacteriological result revealed that water sample from Mgbakwu had the highest significant (< 0.05) total faecal coliform count of 92.50 x 105 ± 45.96 CFU/mL with percentage frequency of 24.96 %, Obibia had the highest significant (< 0.05) total heterotrophic aerobic bacteria count of 74.38 x 105 ± 29.88 CFU/mL with percentage frequency of 23.19 %, and Urum had the highest significant (< 0.05) total faecal Streptococci count of 79.88 x 105 ± 19.44 CFU/mL with percentage frequency of 20.03 %, respectively. Cumulatively, Urum had the highest reciprocal of the Simpson index of 5.089, while Obibia had the lowest cumulative reciprocal of the Simpson index of 4.951; Obibia had the highest Magarlef index of 11.703, while Mgbakwu had the lowest Magarlef index of 11.275; Shannon-Wiener index, Obibia had the highest index of 6.897, while Urum had the lowest Shannon-Wiener index of 6.697; Obibia had the highest Pielou’s evenness index of 3.178, while Urum had the lowest Pielou’s evenness index of 3.058, respectively. Thus, the baseline indices data from this study showed that the three streams were evenly distributed bacteriologically, moderately polluted, and stringent measures should be put in place in order to avert these menaces in the three study areas.