Background Water erosion, upland degradation and deforestation are key environmental problems in Meki river watershed. . The study assessed the land use land cover change (LULCC) over the last 30 years, examined the contribution of the indigenous Enset-Based land use system (EBLUS) which was not studied so far in reducing soil erosion and preventing Lake Ziway from sedimentation. Based on the outcomes, the research recommended appropriate management interventions based on priority mapped to sustainably manage the watershed. GPS based Ground truth data sampling and collection, Geo-statistical interpolation and RUSLE model were applied for soil erosion modeling. The LULCC detection and analysis was conducted to generate the spatial inputs using ERDAS Imagine 2014.
Result Meki river watershed has 2110.4 km² of area which is dominantly covered by cultivated land use system (41.5%), Enset-Based land use system (EBLUS)(10.65%), Bush and Chat land use system (25.6%), Forest and plantations land use system (14.14%), built up (7.4%) and water bodies (0.75%). Severity class of High to severe range (18-125tha-1yr-1) recorded in the sub-watersheds irrespective of the land use systems and facing sever degradation problem that increase in soil loss in all land use systems from 1987 to 2017. The average soil loss of 30.5tha-1yr-1 and 31.905tha-1yr-1 verified from Enset growing zones and non-Enset growing zones of the watershed respectively.
Conclusion Enset-Based land use system (EBLUS) saves significant amount of soil despite the steepness of the slopes of the Enset growing zones of the watershed. Hence, expansion of EBLUS can contribute in sustaining Lake Ziway by reducing soil loss rate and sedimentation problem for ecological sustainability of the watershed. Therefore, separate land use policy and awareness creation are mandatory for such EBLUS expansion, integrated watershed management and conservation of the natural environment in the watershed.