Background With the largest cattle population in Africa and vast swathes of fertile lands infested by tsetse flies, trypanosomosis is a major challenge for Ethiopian farmers. Managing the problem strategically and rationally requires comprehensive and detailed information on disease and vector distribution at the national level. To this end, the National Institute for Control and Eradication of Tsetse and Trypanosomosis (NICETT) developed a national atlas of tsetse and African animal trypanosomosis (AAT) for Ethiopia. Methods This first edition of the atlas focused on the tsetse-infested areas in western Ethiopia. Data were collected between 2010 and 2019 in the framework of national surveillance and control activities. Over 88,000 animals, mostly cattle, were tested with the buffy-coat technique (BCT). Odour-enhanced traps were deployed in approximately 14,500 locations for the entomological surveys. Animal- and trap-level data were geo-referenced, harmonized and centralized in a single database. Results AAT occurrence was confirmed in 86% of the districts surveyed (107/124). An overall prevalence of 4.8% was detected by BCT in cattle. The mean packed cell volume (PCV) of positive animals was 22.4, compared to 26.1 of the negative. Trypanosoma congolense was responsible for 61.9% of infections, T. vivax for 35.9% and T. brucei for 1.7%. Four tsetse species were found to have a wide geographic distribution. The highest apparent density (AD) was reported for Glossina pallidipes in the Southern Nations, Nationalities and People's Region (SNNPR) (3.57 flies/trap/day). Glossina tachinoides was the most abundant in Amhara (AD 2.39), Benishangul-Gumuz (2.38), Gambela (1.16) and Oromia (0.94) regions. Glossina fuscipes fuscipes and G. morsitans submorsitans were detected at lower densities (0.19 and 0.42 respectively). Only one specimen of G. longipennis was captured. Conclusions The atlas establishes a reference for the distribution of tsetse and AAT in Ethiopia. It also provides crucial evidence to plan surveillance and monitor control activities at the national level. Future work on the atlas will focus on the inclusion of data collected by other stakeholders, the broadening of the coverage to tsetse-free areas and continuous updates. The extension of the atlas to data on control activities is also envisaged. Graphical Abstract

Regional and local hydrological regimes are expressively exposed to global climate change, which is considered to be one of the major problems threating water resources and flood security. This research has been done aimed at the examination of the effect of climate change on the hydrology of Borkena watershed, Awash River Basin during 2030s (2021-2040), 2050s (2040-2060), and 2070s (2061-2080) future periods. To realize this, the distributed hydrological SWAT Model driven by three different Global Circulation Models (MIROC5, MPI, and IPSL) under two Representative Concentration Pathway emission scenarios (RCP4.5 and RCP8.5) was used. As result, the GCM projection indicated that, the mean annual maximum and minimum temperature projected to increases by 0.56°c and 0.31°c respectively while the mean annual rainfall has no a significant change in the coming decades. The study also resulted in a considerable average monthly and seasonal, rainfall change in magnitude and direction. Relative to the baseline period the changes in mean annual stream flow from (2021-2080) are mostly negative and indicate a reduction in volume of discharge available in the Borkena river. In addition, trends in the extreme flow are also determined for high and low flows and the results show a forceful negative trend for extreme stream flows and flood volumes may decrease by 43.1% in RCP4.5 under MPI (2021–2040), 38.6% (2041–2060) and 49.4% (2061–2080) in RCP8.5 under IPSL and MIROC5 respectively. These findings will serve as a nearly warning for the alarming extreme weather events for the future period in Borkena watershed as well as Awash River basin which require sustainable and effective adaptive measures for future water resource management.

The objective of this study is evaluating channel stability investigation and recommend appropriate mitigation measure of Mersa river, Awash basin Ethiopia. HEC-RAS5.0.7 model with BSTEM (its extension) was used for assessing Mersa riverbed and bank stability and identifying flood prone area. To achieve the objective both filed investigation such as river cross section data collected, soil sample taken and experimental tasks such as sieve analysis, triaxial compression test are carried out. HEC-RAS model simulation with Yang sediment transport formula is best representative for study reach as compared to Meyer Peter and Muller sediment transport method. For entire simulation period an average aggradation was 1.24m and 0.98m at upstream and downstream reach respectively, whereas average degradation on both upstream and downstream reach was 1.25m. The average erosion generated from Mersa river was 22.47kt/yr. Both aggradation and degradation were observed on the study reach but Mersa river reach more affected in erosion than deposition. Mersa riverbank stability and toe erosion assessed by BSTEM of HEC-RAS was safe and again bank toe neither aggrade nor degrade in response to the flow. Additionally, Water surface of Mersa river was computed using steady flow analysis shows that flood over top above the bank, adjacent area (Mersa town) was severed by flood and the reality also true. The reality also true especially due to flood loss their farmland and different property. Finally, this investigation presented that channel bed was unstable while bank was stable. Different stabilization measures like Gabion bank, Check dam and drop structure were recommended to prevent flood prone area from flood and to control channel bed instability.

Regional and local hydrological regimes are expressively exposed to global climate change, which is considered to be one of the major problems threating water resources and flood security. This research has been done aimed at the examination of the effect of climate change on the hydrology of Borkena watershed, Awash River Basin during 2030s (2021–2040), 2050s (2040–2060), and 2070s (2061–2080) future periods. To realize this, the distributed hydrological SWAT Model driven by three different Global Circulation Models (MIROC5, MPI, and IPSL) under two Representative Concentration Pathway emission scenarios (RCP4.5 and RCP8.5) was used. As result, the GCM projection indicated that, the mean annual maximum and minimum temperature projected to increases by 0.56°c and 0.31°c respectively while the mean annual rainfall has no a significant change in the coming decades. The study also resulted in a considerable average monthly and seasonal, rainfall change in magnitude and direction. Relative to the baseline period the changes in mean annual stream flow from (2021–2080) are mostly negative and indicate a reduction in volume of discharge available in the Borkena river. In addition, trends in the extreme flow are also determined for high and low flows and the results show a forceful negative trend for extreme stream flows and flood volumes may decrease by 43.1% in RCP4.5 under MPI (2021–2040), 38.6% (2041–2060) and 49.4% (2061–2080) in RCP8.5 under IPSL and MIROC5 respectively. These findings will serve as a nearly warning for the alarming extreme weather events for the future period in Borkena watershed as well as Awash River basin which require sustainable and effective adaptive measures for future water resource management.