Impacts of Human Activities on selected Physico-Chemical Parameters and Macroinvertebretes of Lake Tana, Northwestern Ethiopia

Abstract

Human activities degraded the water quality and biodiversity of Lake Tana. This study is; therefore, aimed to analyse the impact of anthropogenic activities on Lake Tana based on a correlation study of physico-chemical parameters and macroinvertebrates. Samples were collected in eleven sites in the littoral zone of the lake. Physico-chemical parameters were measured following water quality assess- ment protocols. Collected macroinvertebrates were identified using standard keys. Correlation analysis between physico-chemical, heavy metal and coliform parameters and macroinvertebrates was conduct- ed by using multivariate (Pearson) correlation.Similarly, physico-chemical parameters and macroinver- tebrate taxa were highly positively correlated with each other (P < 0.01). Some of the physico-chemical parameters and macroinvertebrate taxa correlations positively significant at 0.01 level were TDS and Muscidae (0.673), As and Chironomidae (0.812), Pb and Gerridae (0.811), Pb and Corixidae (0.591), Pb and Notenoctidae (0.780). We conclude that the main threat to Lake Tana arises from agricultural ac- tivities, urbanization and industrialization that deteriorated its water quality and biodiversity which is pronounced by the physico-chemical parameters & macroinvertabrate indicators amount. Thus, proper management of Lake Tana should be put in place to improve water quality and biodiversity of the lake for sustainable development.