Temesgen Alemneh Yimanie
Aalborg University
Title: Modeling the impact of highland settlements on ecological disturbance of streams in Choke Mountain Catchment: Macroinvertebrates’ assemblages and water quality
Biography
Biography: Temesgen Alemneh Yimanie
Abstract
Human disturbances of waterways in Ethiopian highlands have increased throughout the last century due to population growth and increased land use. Despite this there is a lack of knowledge on macroinvertebrate responses to human disturbances and the application of biological monitoring in tropical highland waterways in general. In this study, we have evaluated the human impact on the ecological integrity of the Chemoga River catchment in the Choke mountain watershed at the northwestern region of the Ethiopian highlands. During wet and dry seasons, the water quality and macroinvertebrate assemblages were assessed. Multivariate statistics and Canonical Correspondence Analysis (CCA) were used to identify factors influencing macroinvertebrate community structures in highland streams in the northwest regions of Ethiopia. A total of 66 taxa of benthic macroinvertebrate were recorded, among which Diptera (38%) and Coleoptera (21%) were the dominant. The biomonitoring results revealed a severe decrease in the ecological integrity of the Chemoga River in terms of macroinvertebrate composition at higher altitude. The ordination and cluster analysis clearly indicates extremely low macroinvertebrate diversity at sites where human impact is severe and a strong effect of altitude. Moreover, anthropogenic activities may have caused changes among physicochemical parameters, which have led to depletion of aquatic macroinvertebrates in the Chemoga River. These results highlight the need to protect the ecology of Chemoga River and that of similarly degraded watersheds in the Ethiopian highlands