ECOLOGICAL IMPACTS OF ECOHYDROLOGICAL INTERVENTION ON THE WETLANDS ALONG THE SOUTHEASTERN SHORE OF LAKE TANA, ETHIOPIA

Abstract

Lake Tana watershed wetlands have critical functions of nutrient and sediment retention, biodiversity and hydrological functions. Although ecohydrological solutions have been proposed, a comprehensive study on the impacts of ecohydrology intervention in relation to biological aspects is limited. Information regarding the ecological impacts of ecohydrology based intervention approach in the wetland ecosystem plays an indispensable role in increasing biodiversity and improves water quality. Thus, the aim of this study was to investigate the impacts of ecohydrological intervention in relation to macrophytes, phytoplankton and zooplankton of the wetlands in Lake Tana shore. Quantitative characteristics of macrophytes and plankton sampling were conducted using transect and quadrat method along vegetation and water depth gradients. The biological data were measured on each fixed sampling point. Macrophytes, phytoplankton and zooplankton were significantly different (p<0.05) across the sampling sites. Low disturbed wetland supports higher abundance and diversity of macrophytes, phytoplankton and zooplankton than moderately and highly disturbed wetlands. Overall results of the study confirmed that biological abundance and diversity were associated with the level of disturbance of wetlands. Therefore, emphasis should be given to the factors which may lead to the degradation of wetland resources within and its catchment. Immediate ecohydrology based intervention approaches should be implemented to conserve and minimize further degradation of wetlands along the shore of Lake Tana.