JavaScript is disabled for your browser. Some features of this site may not work without it.
| dc.contributor.author | Zewdie, Ewnetu | |
| dc.date.accessioned | 2020-03-17T07:07:39Z | |
| dc.date.available | 2020-03-17T07:07:39Z | |
| dc.date.issued | 2020-03-17 | |
| dc.identifier.uri | http://hdl.handle.net/123456789/10487 | |
| dc.description.abstract | Hydraulic structures such as dams have inevitable effects on their downstream that requires investigation. This study addressed the impacts of land use change and hydraulic structures on river morphology in Shina watershed, Lake Tana basin, Ethiopia. Objectives of this thesis were to assess the impacts of land use change in view of river characteristics, to assess Shina river planform changes and to investigate vertical change of Shina river downstream from the dam. Satellite images of the year 1986, 2001 and 2017 were used for land use/ land cover classification and river planform analysis. To compare the vertical adjustment of the Shina River, current river cross-sections were taken at different intervals and the past cross sections were developed from the old topographic map of the study area. For the data preparation and analysis image processing software (ENVI 5.1) and Arc GIS 10.2 were used. From the result of land use /land cover classification, there is a decrease in forest land by 70%, the Bushes and shrubs by 48% and accompanied by increase in agriculture land by 23% and built up area by 26%. The anthropogenic impacts such as farming, deforestation, resettlement and animal free grazing have also aggravated the change of the planform in the downstream part of the river. The overlaying analysis showed that for the considered reach (6km length), starting from the dam for a length of about 3 km the general trend of the river banks were shifted to right and after that the river banks shifts left. Comparisons of cross-sections at junctions of spillway outlet and Shina river, at a distance of 210 m and 410 m from the dam axis to the downstream showed that the river bed degraded by 0.38 m,0.94 m and 0.42 m for the period 2007and 2017 respectively. The conclusion of this thesis showed that Shina river morphology has been changed due to land use / cover changes and hydraulic structure. Therefore, upstream catchment treatment and downstream river restoration should be done. | en_US |
| dc.language.iso | en | en_US |
| dc.subject | Hydraulic engineering | en_US |
| dc.title | IMPACTS OF LANDUSE CHANGE AND HYDRAULIC STRUCTURES ON RIVER MORPHOLOGY: A CASE STUDY OF SHINA MICRO EARTH DAM, LAKE TANA BASIN. | en_US |
| dc.type | Thesis | en_US |
