Browsing by Author "Getnet, Habtamu"

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    Effects of Water Hyacinth (Eichhornia Crassipes) on Water Quality and Composition and Abundance of Phyto- and Zooplankton in the Littoral Region of Koka Reservoir, Ethiopia
    (Addis Ababa University, 2019-05-05) Getnet, Habtamu; Kifle, Demeke (PhD); Fetahi, Tadesse (PhD)
    Invasion of aquatic habitats by non-native species is a global environmental challenge with serious ecological, social and economic consequences demanding urgent action. Water hyacinth, Eichhornia crassipes (Martius) Solms, is one of the world’s most rampant invasive aquatic plants recognized as one of the top 10 worst weeds in the world. Its appearance in Koka Reservoir was reported in 1965 and has become a threat to the aquatic ecosystem. Although several limnological studies have been made on the reservoir, the effects of water hyacinth on water quality and plankton have not been addressed. Samples were collected monthly from three weed-infested and three non-infested sites from March to July 2018 to assess its effect on water quality, plankton composition and abundance in the reservoir. Potential toxicity of water hyacinth extract was also investigated using white albino mice. During this investigation, the differences between weed-infested and non-infested sites in DO, NO3-N, NO2-N, SRP, TP, NH3, TSS, Turbidity, Silica and Secchi disk depth were significant (P<0.05), with lower values in the weed-infested sites except values of TSS, Silica and Turbidity higher in the weed infested sites. The phytoplankton community, which was constituted of 62 species, was dominated by Bacillariophyceae (mainly Aulacoseira granulata) followed by Cyanophyceae (Cylindrospermopsis spp., Microcystis aeruginosa, and Anabaena flos-aquae) and Chlorophyceae in both non-infested and weed-infested sites. The variations in the abundance of phytoplankton and zooplankton between the two sites were significant (p<0.05). The phytoplankton species Monorophidium griffithii and Gyrosigma obtusatum and the zooplankton taxa Lecane monostylahomata, Lecane leontita, Trichocerca djurellasejunctipes, Euchlanis menta, and Platyias quadricornis var. bervispinus were found only in the weed-infested sites. Significant differences in Shannon’s index (H'), species richness (d) and species evenness (j) of zooplankton and species richness (d) of phytoplankton were also observed between the two sites, with higher mean values in the non-infested sites than in the weed-infested sites (p<0.05). Rotifers, followed by Copepods and Cladocerans in the same order, were the most abundant at both sites. The relative density of Rotifers and Cladocerans was higher in the non-infested sites, while that of Copepods was higher next to Rotifesrs in the weed-infested sites. Results of the experimental test on the toxicity of water hyacinth on white albino mice showed unusual changes although the death of the treated mice was not observed suggesting the potential toxic effect of the weed on aquatic biota that would occur with an increase in dose and duration of administration. The existing infestation level of water hyacinth poses a significant effect on water quality, composition and abundance of phytoplankton and zooplankton. The current environmental conditions are favorable for the optimum growth of the weed and further proliferation of the weed and spread to new areas are possible worsening its adverse effect to the ecosystem. Thus, continuous monitoring and development of a sustainable management strategy and regulation of agricultural and urban wastes, have to be addressed.
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    Livelihoods and Survival Strategies Among The Migrant Shoe-Shinning Children: A Case Study at Arada Sub-City, Addis Ababa.
    (Addis Ababa University, 2016-03) Getnet, Habtamu; Tolossa, Degefa (PhD); Abebe, Tatek (PhD)
    Qualitative research approaches and methods that broadly fall under abservations and interviews are the principal methods employed to uncover and understand what lies behind any phenomenon involved in the daily experiences of the children because the natural context of the children's lives and the inte/personal and socia-cultural fabric injluences their livelihood perspectives, experiences and actions. Besides, using the case study research approach, we attempted to assess the social networks and or relationships constructed by the children. In fact, the whole process of generating the research data was primarily made on the basis of the children's own perspectives and understanding of their work and livelihood conditions. In doing so, I asked them how they think of their lives in their own terms and gave their own viewpoints. Poor rural parents are unable to provide education and basic survival needs to their children. As a consequence, children are ojlen obliged to quit school and joined the city streets in search of employment in the informal sector. In fact, working (shoe -shinning) children discontinued education not because they are uncaring to school rather due to lacking assistance from their parents because of families' impoverishment, and death or disharmony. Mostly, children are obliged to dropout at school and migrated 10 the city in search of work not because of the net benefits of attending school are low relative to the rewards from shoe-shinning work. Even though, the study children properly acknowledged that attending school is absolutely vital for their life, it was beyond their capability to pursue education because their families are impoverished and unable to send them to school. It was mainly due to lacking basic survival needs that children are obliged to work. Thus, survival is the foremost and an irreplaceable agenda than schooling for the needy children. The study reveals that the livelihoods of the shoe shiners are dynamiC and there is an intense solidarity among shoe-shinning children in Addis Ababa city. Most of them maintain very close social ties and networks with peer groups, relatives, customers, and with other street actors. The most predominant social tie and or network is peer group socialization which is mainly constructed on the basis of identical work and geographical origin. Those who came from the same geographical origin and or rural village form a unified functional group and develop high sense of belongingness. They live and work together for getting the benefits of communal life style. Children conceived that living together is the sale livelihood strategy which enables to reduce urban living cost and perhaps makes life easier and enjoyable. They use their social networks and bonds to overcome some of the challenges they face such as redUCing their meals and sharing apartments with colleagues as well as relying on each other's help in times of scarcity. Moreover, they create a new sense of family-hood' with their social groups and exercise a sense of enthusiastic love and care to each other. At times they suffer, they usually share material and financ ial benefits from each other. For instance, if a child lacks income to get food, friends will invite and or lend some money. If somebody is sick or injured they would take him to the clinic or give treatment at home. Shoe-shinning children one among the urban poor in Addis city, have been exposed to various vulnerable living conditions. Most of them lack adequate livelihood income and basic necessities which in turn affected their spatial well being and health conditions as well. Miserable life due to the failure to completely acclimatize and mitigate the urban life constraints (such as the high cost of living (rising food price, and high house rent cost), injlation, poor housing access, insecure wage, and poor sanitation), have been aggravating the vulnerability conditions of these children. In general, lack of access to suffiCient resources and vulnerability to the aforementioned urban life hazards, stresses and shocks are responsible for the unsustainable livelihoods, poor wellbeing and lack of the children's basic necessities.