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Water quality impairment, due to anthropogenic activities and limited enforcement capacity, is a rapidly growing threat to water security as well as public health in developing countries. Cumulative effects of deteriorating water quality undoubtedly put pressure on public health and socio-economic developments. For example, most industries in Ethiopia discharge their effluent directly into freshwater systems without any treatment process. The problem is severe for rivers such as the Awash that pass through major cities. Although there were a few studies that looked into the issue, there is a lack of comprehensive water quality impact assessment on agriculture, health, and socio-economics. This article systematically summarizes current research on water quality issues in the Awash River Basin to generate comprehensive information that captures the water quality status of the river and impacts of water contamination, and identify information and management gaps. Results showed that water quality degradation along the river course and in selected tributaries exceeds water quality standards by the WHO and national guidelines. For example, E-coli bacteria concentration in two tributaries, Tinishu and Tiliku Akaki, reach up to 6.68 and 6.61 billion CFU 100 ml/L. Virological profile of creeks receiving wastewater from hospitals in the City of Addis Ababa contains coliphages levels reaching as high as 5.2 × 103 pfu/100 ml for urban rivers and up to 4.92 × 103 pfu/100 ml. Heavy metals that far exceed the tolerable levels for humans were also detected in vegetables produced using impaired water. Heavy metals such as Cd, Cr, Cu, Hg, Ni, and Zn were detected in potato, Zn and Hg in Cabbage, and Cr in onion and red beet. Lettuce irrigated with Akaki river water found to contain 0.263 (Cd), 420 (Fe), 13.44 (Zn), 7.87 (Cr), 7.49 (Cu), and 6.55 (Pb) in mg/kg both in excess of WHO guideline. In addition, a high concentration of Cr has been also found in fish tissues. There has never been a systematic evaluation of the impact of contaminated water in the Awash Basin. Comprehensive impact of water quality investigation that takes into account the different pollutants dynamic needs to be made to protect the well being of downstream beneficiaries including the aquatic ecosystem. In conclusion the systematic review has shown that for a river that cross-through emerging mega-city like Addis Ababa, the human and ecosystem health impact of aquatic ecosystems pollution should not afterthought action

Background: Even though increasing population pressure and associated increased demand for food and economic development have led to overexploitation and degradation of wetlands throughout the world, the drivers are most severe in developing countries. For generations, Fogera wetlands in Ethiopia which are parts of Lake Tana Biosphere Reserve have been widely used for grazing of indigenous cattle. Fogera cattle are one of several recognized indigenous breeds of Abyssinian zebu bovine cattle (Bos primigenius indicus) found in Fogera district, Ethiopia. This study was conducted to quantify impacts of rice expansion on cattle population in Fogera wetlands. Data were collected through questionnaire, focus group discussions, interviews, and land use/land cover analysis. Respondents were selected using systematic random sampling. Variance and LEVENES test were used to analyze the livestock unit and to check homogeneity. Results: The study revealed that during the 20-year period preceding 2015, the number of cattle owned decreased from 3509 to 1510 heads. In the same period, rice cultivation increased from 182 to 9499 ha and production from 6701 to 714,013 qt. Grazing lands were reduced from 8550 to 3501 ha, wetlands from 3114 to 1060 ha, and forests from 1542 to 907 ha. Land use/land cover changes showed a negative balance of 40% dry matter requiring cattle feed to be increasingly supplemented through purchases, or reduction in herd number. The study also indicated that the land-use changes brought at the expense of traditional cattle production systems. Conclusion: Hence, proper management is required to maintain these valuable resources and keep their role in socioeconomic development of the area.

Ethiopia has the largest livestock population in Africa with 35 million tropical livestock units. The livestock system relies on natural open grazing which is affected by frequent droughts. However, little research exists that studies the suitability of the biophysical environment for fodder production and the risks due to climate change. The main objectives of the study are to evaluate the potential effects of climate change on land suitability for alfalfa production in Ethiopia and to assess the extent of irrigation requirements for alfalfa growing under the adverse climate change projections. The impact of climate change on land suitability for alfalfa was evaluated using projected changes in rainfall and temperature based on three global circulation models (CCSM4, HadGEM2-AO, and MIROC5). A multi-criteria evaluation in GIS that uses biophysical, climatic and topography factors was applied to identify the suitable land. The highly suitable area under current climate scenarios covered ~472,000 km2, while moderately suitable and marginally suitable covered ~397,000 km2 and ~16,200 km2, respectively. The projected climate alters the suitable land for fodder production across Ethiopia. Expansion of suitable land occurred in the highlands where climate scenarios predict an increase in temperature and precipitation. Dryland regions showed a rainfall deficit for the three model projections. The research provides guidelines for growing alfalfa in Ethiopia considering ecological and climatic variability.

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