EFFECTS OF BEER FACTORY EFFLUENT DISCHARGE ON BENTHIC MACROINVERTABRATE DIVERSITY AND WATER QUALITY OF META RIVER IN SEBETA TOWN, ETHIOPIA

Abstract

The use of benthic macroinvertabrates together with physico- chemical parameters are considered as the reliable method for water quality assessment. The main objective of this study was to determine the water qualities of Meta River using biological and physico chemical parameters. One reference site which is less affected by the beer factory effluent discharge and two affected sites in the down stream were used to collect the water samples. A total of three water samples were collected from the three sampling sites. Each water sample was subjected to various physico-chemical analyses. Nine physico-chemical parameters pH, temperature, E.C, TDS, salinity, turbidity, nitrate-nitrogen, nitritenitrogen, phosphate were used. There were significant differences in most of the physicochemical parameters (p<0.05) between reference and impacted sites. Higher value of EC, Salinity, TDS, nitrate-nitrogen, and Nitrite-nitrogen was recorded at affected sites (site II and site III) than reference site (site I). Most of the physico-chemical parameters were out of WHO and EPA water quality standared. Total of 392 benthic macro invertabrates belonging to 10 species were collected. In addition, identification and quantification of benthic macro inveretabretes was carried out for each sampling sites. Most of the benthic macro invertabrates significantly correlated with almost all physico-chemical parameters. Chironomus riparius was correlated positively with Temprature (r=0.851), TDS(r=0.9270), Nitrate (r=0.858) and Nitrite (r=0.898). The Hilsenhoff biotic indexI was categorized under good water quality in contrast to results of physico-chemical parameters. Reference site I had large number of macro-invertebrates with moderate tolerance and pollution sensitive groups. Waste water discharged to the nearby Rivers has enormous effect on the degradation of the ecosystem. From this study we conclude that Beer factory Effluent affects the quality of Meta River. To sustain the ecological conditions of the nearby Rivers, wastewater treatment and environmental audit are suggested. categorized the impacted sites under poor very substantial pollution water quality but site