http://ir.bdu.edu.et/handle/123456789/1990 Sat, 13 Jan 2001 06:30:58 GMT 2001-01-13T06:30:58Z http://ir.bdu.edu.et/handle/123456789/16853 Assessment Of Groundwater Vulnerability To Pollution Using Modified Drastic Model In Bure Town, Ethiopia Atinkut, Kelemu Groundwater resources, which account for about 30 percent of global freshwater, are the most abundant, clean, and important resource for human and ecosystem adaptability. However, the quality of groundwater is gradually deteriorating due to rapid population increase, urbanization, climate change, and anthropogenic activities. So, groundwater quality protection has become a global concern. One of the mechanisms for protecting groundwater quality is vulnerability assessment to test its sensitivity to pollution. The study was carried out in Bure town which hosts a large number of population settlements and several industries with no good working waste stabilization ponds. The study aimed to assess the vulnerability of groundwater to pollution in Bure town using the modified DRASTIC model. In this study, the modified DRASTIC model was used which integrated eight parameters including depth to water, net recharge, aquifer media, soil media, topography, the impact of the vadose zone, hydraulic conductivity, and land use land cover. The spatial variation of vulnerability was identified by integrating the thematic layers using a raster calculator tool on the GIS environment. Primary data types such as remote sensing data and meteorological data were primary data as well as secondary data inputs such as geological maps, soil maps, hydrogeological log data, pumping test data, static water levels, and water quality data were used. The result of vulnerability revealed vulnerability index value of the study area ranges from 74 to 173. Accordingly, 67.05% of the area was under medium to high vulnerability zone. Areas with a high vulnerability index (35.82%) were found in the central and northwestern part of Bure town in association with industrial, residential, and intensive agricultural areas respectively while low vulnerability zones (32.99%) were found in most of the eastern peripheral part in association with plantation and other open areas. The validation of the model using Pearson's correlation coefficient "R2" was determined to be 0.55 suggesting a positive correlation between the nitrate value and vulnerability index. Sensitivity analysis revealed that the depth to water level and the land use factor were influencing factors. The spatial variation of water quality parameters showed variations from one site to another although most of them are within the acceptable limits. The value of pH ranges from 6.5 to 8.4, indicating the acidic to alkaline nature of the water which was supported by variations in EC and TDS which range from 331.9 μS/cm to 5429.6 μS/cm and 215.8 and 3555.3 mg/L respectively. Higher levels of nitrate (33.9 mg/L) were revealed in northwestern sites where intensive agriculture (as a non-point source) is practiced followed by residential and industrial areas. A strong correlation between agricultural Wed, 01 Jan 2025 00:00:00 GMT http://ir.bdu.edu.et/handle/123456789/16853 2025-01-01T00:00:00Z http://ir.bdu.edu.et/handle/123456789/16847 Groundwater Quality Potential Zones Delineation Using Geographic Information System and Analytical Hierarchical Process: the case of East Gojjam Zone, Amhara Regional State, Ethiopia Eskemeche, Temesgan Water is the prime natural resource, which is basic for healthful functioning of any ecosystem. However, estimating the groundwater quality potential zone has remained uncertain and less studied due to its complex nature. In the East Gojjam zone, the surroundings of Debre-Markos Town; in particular, groundwater development for various purposes is increasing. Therefore, assessment of the groundwater potential is very crucial for sustainable use of groundwater. Satellite images have been widely used for groundwater exploration because of its capability to identify indicators of groundwater potential zones. The main objective of this study it to delineate the groundwater potential of East Gojjam Zone, Amhara region, Ethiopia using geo information system combined with analytical hierarchal processes and water quality index methods. A purpose full sampling technique with a minimum of 50 sample size were collected from each category through observation and transact walkover. By consulting existing literatures, for this study ten most important groundwater controlling factors:- lithology, lineaments density, drainage density, geomorphology, rainfall, slope, land use land cover, elevation, and soil depth and soil texture that derived from satellite data and existing secondary data were selected. These thematic layers were prepared and converted to raster data format. Then, weightages were assigned for each thematic layers and ranked based on the knowledge that gained from literatures and expert opinions. Finally, the thematic layers overlaid to determine the groundwater potential based on the assigned rank and weight using Arc GIS spatial analysis tool. The groundwater potential map was validated through receiver operating characteristics (ROC) method of area under the curve (AUC) value were used based on wells yield data that are collected from different offices. The groundwater quality map was prepared based on the 52-groundwater point data of having quality test and yield results with geographic coordinates. The Ethiopian drinking water standard of 2013 using the WQI technique was used to test the groundwater quality. The results show that there are good agreements of 91.8% between the predicted groundwater potential map and the existing groundwater wells data. The groundwater quality potential map was reclassified into three groundwater quality potential zones of very high, high, and moderate. The result indicated that, about 92.09% (12,864.88 km2) of the study area was high, 6.24% (871.6 km2) of the study area was very high, and 1.67% (232.7728 km2) as moderate groundwater quality potential zone. The study suggested that, generated GWPZM would serve as useful guidelines for planners, engineers, and decision makers providing quick decision- making in the management of groundwater resources. Wed, 01 Jan 2025 00:00:00 GMT http://ir.bdu.edu.et/handle/123456789/16847 2025-01-01T00:00:00Z http://ir.bdu.edu.et/handle/123456789/16844 Integrated Geospatial-Based Suitable Site Identification for Forest Landscape Restoration in Libokemkem District of South Gonder, Ethiopia Zelalem, Teshager Forest degradation significantly impacts biodiversity, carbon storage, water regulation, and forest-dependent livelihoods, necessitating effective restoration efforts. Identifying optimal sites for forest landscape restoration is critical for sustainable forest management. This study employed a GIS-based Multi-Criteria Decision Analysis (MCDA) using the Analytical Hierarchy Process (AHP) to assess forest landscape restoration suitability in Ethiopia's Libokemkem District. Sampling techniques and data collection instruments involved acquiring high-resolution geospatial data from diverse sources, including ALOS PALSAR DEM (12.5m), PERSIANN-CCS rainfall (4km), Sentinel-2 LULC (10m), FAO soil maps, and OpenStreetMap for infrastructure. Ground truth data from Google Earth validated the LULC map, achieving an 85% overall accuracy and a Kappa coefficient of 74%. Expert judgment, formalized through AHP pairwise comparisons, determined factor weights. The Consistency Ratio (CR) of 0.056 (5.6%) confirmed high judgment reliability. LULC (26%), Slope (20%), Distance from Forest Patches (15%), and Proximity to River (13%) emerged as the most influential factors. Conversely, Distance from Roads and Settlements (both 3%) had minimal influence. The Weighted Overlay Analysis revealed that the majority of the district (61.29%) is Moderately Suitable (S2) for restoration, covering 845.93 km2. Marginally Suitable (S1) areas constitute 38.10% (525.84 km2), while Highly Suitable (S3) sites are scarce, accounting for only 0.62% (8.49 km2). Negligible areas were classified as Not Suitable (N). This geospatial framework provides a robust, data-driven foundation for strategically prioritizing and implementing targeted forest restoration initiatives across suitable zones. Its application is crucial for enhancing ecological resilience and fostering sustainable socio-economic benefits in the region. Sun, 01 Jun 2025 00:00:00 GMT http://ir.bdu.edu.et/handle/123456789/16844 2025-06-01T00:00:00Z http://ir.bdu.edu.et/handle/123456789/16843 GIS-Based Assessment of Slum Settlements in Bahir Dar: Physical Attributes and Environmental Challenges of slums Tadele, Yeheyis Rapid urbanization has led to the proliferation of slum settlements in developing countries. This research main objective is to identify and assess the existing situation of slum settlements in Bahir Dar city, and to understand the environmental challenges they pose. The research used mixed research approach and combined multi-temporal Google Earth imagery with ground site observations to monitor slum growth, to map building footprints and to analyze slum settlement patterns. Primary data were drawn from the Bahir Dar Structural Plan (BDSP) household questionnaire administered to 1,000 respondents, complemented by site observations, key informant interviews, and secondary sources. The UN-Habitat slum indicators are used to identify and characterize slums in Bahir Dar. The findings reveal that Bahir Dar's slum settlements fail to meet the minimum standards for livable housing. An important characteristic is insecure tenure, with many settlements being informal. Most of the housings have low structural quality and durability, because of the use of temporary materials like wood and mud for walls which account for 91% of the slum settlements. These materials are structurally weak, vulnerable to decay, moisture, pests, and fire. Additionally, the settlements suffer from inadequate infrastructure and basic municipal services. While access to private toilets exists for 70.3% of the slum settlements, from these toilets 69.5% are pit latrines which pose risks for groundwater contamination. Liquid waste management is also a major challenge, with 55.9% throwing away liquid waste, leading to pollution. Solid waste collection is also inefficient, with 77% of houses that don‟t get municipal service in the city are located in slum settlements resulting in rampant disposal in drainage lines, roads, and water bodies. The GIS based spatial analysis shows that slum settlements are unplanned characterized by irregular layouts, high built-up densities (43% to 74%), limited open spaces, and poor road networks. These physical characteristics have contributed to different environmental challenges and also decreased environmental quality of the settlements. The study concludes that Bahir Dar's slum settlements are unsafe to both inhabitants and the environment. Recommendations include short-term slum upgrading programs, and long-term urban renewal for deteriorated, unplanned areas. The use of GIS in urban planning is suggested as vital for data driven slum interventions, and comprehensive policy and governance reforms are suggested to address the root causes of slum formation Sun, 01 Jun 2025 00:00:00 GMT http://ir.bdu.edu.et/handle/123456789/16843 2025-06-01T00:00:00Z