Ayana Angassa

Prof. Ayana Angassa


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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31 July 2017 in Ecological Processes
Verified
Journal Article
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GWGalma Wako
Galma Wako
MTMenfese Tadesse
Menfese Tadesse
AAAyana Angassa
Ayana Angassa
Experiences of low rainfall and frequent droughts have had enormous impacts on livestock production and pastoralists’ livelihoods in southern Ethiopia. The Borana pastoralists are dependent on livestock husbandry with the dominance of cattle in their herds for generations. Recently, the Borana communities have engaged in extensive livestock species diversification, with more focus on camel management as an adaptation strategy to the severity of recurrent droughts. Although increasing interests in camel management among the Borana pastoralists are acknowledged, the driving forces for the increase in camel population in the region have not been addressed. The aim of this study was to assess the trend in camel management as an adaptation strategy towards climate change among the Borana pastoral households. The study also investigated evidence of climate change and the driving factors for camel adoption. The study was conducted in three purposively selected kebeles, which is a lower administrative unit in Ethiopia, of Yabello district in Borana Zone in southern Ethiopia focusing on 156 randomly selected camel-owning households. The study employed both quantitative and qualitative methods whereby data gathering tools such as key informant interviews (KII), focus group discussions (FGD), household surveys (HS), and field observations were used. The data were analyzed by descriptive statistics using SPSS software version 16. Pastoralists’ perceptions and the existing meteorological data analysis showed an increasing trend in temperature but a decreasing pattern in rainfall over the last 27 years (i.e., during the last four Gada periods). Both pastoralists’ observations and existing meteorological data analysis showed an increasing incidence of recurrent droughts with decreasing availability of grazing and water resources. Respondents further explained that cattle are more vulnerable during severe droughts. The findings also showed that camel management as an adaptation strategy by the Borana pastoralists began recently and showed a steady increase in trend over the last four Gada periods. Pastoralists’ perceptions and the existing analysis confirmed that camels’ potential for high milk production and their capacities to withstand harsh environmental condition are among the many reasons that contributed to the adoption of camels by pastoralists in southern Ethiopia. Camels were also more preferred with the changing ecology of rangeland vegetation dynamics towards bush encroachment. It seems that the high potential of camels for milk production and their abilities to withstand harsh environmental conditions are the major driving forces that contributed to the adoption of camels by pastoralists in southern Ethiopia. Hence, the adoption of camels by pastoralists in southern Ethiopia could be best understood in terms of livelihood diversification option to ensure the food security of pastoral households. We conclude that the increase in camel population in Borana during the last four Gada periods could be attributed to communities’ responses to the impact of climate change and frequent droughts.

4 May 2016 in Ecological Processes
Verified
Journal Article
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TATeshome Abate
Teshome Abate
AAAyana Angassa
Ayana Angassa
Analyzing trends of land use systems and the changes occurred overtime is an effective way of assessing the impacts of land use/land cover (LULC) changes on ecosystem function. It provides important insights for understanding the spatial patterns of land use processes. The rangelands of southern Ethiopia are adversely affected by increased human population pressure, encroachment of crop cultivation, and bush encroachment. Hence, it is vital to understand the trends of rangeland vegetation cover dynamics. This paper evaluates land use/land cover changes and spatial patterns between 1987 and 2003 in Yabelo (5426 km2), Borena rangelands of southern Ethiopia. We used a combination of three Landsat Thematic Mapper (TM) 1987, Landsat TM 1995 and Enhanced Thematic Mapper Plus (ETM+) 2003, and local perceptions. A pixel-based supervised classification with maximum likelihood classifier was used to classify images. The accuracy of classification was assessed for 1987 (81.8 %), 1995 (84.6 %), and 2003 (81.3 %). The results showed that the Borana rangelands had undergone substantial changes during the last 16 years. Between 1987 and 2003, we observed a considerable increase in woodland cover (11.7 %), bushland cover (17 %), cultivated land (72.5 %), and settlements (79.8 %). The results showed a rapid decline in grassland cover (7.7 %), shrubby grassland cover (86 %), and bareland (0.7 %). The spatial pattern analysis indicate that the Borana rangeland was fragmented and characterized by the proliferation of large numbers of patches with a decline in patch index, increased patch density, and irregular shape of patches within a landscape. Local communities’ perceptions indicate that recurrent drought, increased human population size, and expansion of cultivation were largely responsible for the observed LULC changes in the study area. LULC changes contribute to rangeland degradation and weaken the traditional practices of rangeland management. We suggest appropriate management measures to halt the impact of disturbances on LULC dynamics and its implication on the livelihoods of the Borana pastoralists.

20 June 2019 in Agriculture
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YJYonas Jagisso
Yonas Jagisso
Lars Olav EikLars Olav Eik
Lars Olav Eik
ANAjebu Nureta
Ajebu Nureta
AAAyana Angassa
Ayana Angassa
JAJens B. Aune
Jens B. Aune
This paper assesses the ability of fodder plants to reduce methane (CH4) emissions while simultaneously improving animal productivity in Ethiopia. Enteric CH4 emissions from ruminants in Ethiopia increased by 12% or ≈ 6197 Gg CO2-eq. in 2017 compared to the year 2011. In this study, six tropical multipurpose forages (Leucaena leucocephala (Lam.) de Wit, Moringa stenopetala (Bak.f.) Cuf., Sesbania sesban (L.) Merr., Cajanus cajan (L.) Millsp., Crotalaria juncea L., and Lablab purpureus L.(Sweet)) and maize stover were characterized in terms of chemical composition, in vitro CH4 production, and CH4 concentration (%). The objective was to identify forages with low CH4 production potential but with adequate forage quality. The forages differed significantly in chemical composition and in enteric CH4 emission. The dry matter (DM), ash, crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), and acid detergent lignin (ADL) ranged between 89.4–95.4%, 6.08–12.5%, 3.3–30.7%, 20.4–76.0%, 10.8–44.8, and 2.9–14.1%, respectively. All forage plants, except maize stover, contained high CP content above a threshold value (i.e., 7%). Cajanus c. generates the lowest amount of CH4 (32.83 mL/0.2 g DM incubated). CH4 concentration (%) was used as a potential indicator to determine the capacity of a plant to lower CH4 production. Among the studied species, L. purpureus showed the highest CH4 reduction potential (16%) followed by C. juncea (23.45%), M. stenopetala (24.2%), and L. leucocephala (25.5%). M. stenopetala was the most frequently preferred by the farmers followed by C. juncea and L. leucocephala. We concluded that M. stenopetala, C. juncea, and L. leucocephala can be promoted as valuable feed resources for ruminants while simultaneously reducing CH4 emissions.

10 August 2017 in Ecological Processes
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Journal Article
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MMinyahel Tilahun
Minyahel Tilahun
AAAyana Angassa
Ayana Angassa
AAAster Abebe
Aster Abebe
Pastoral communities have a comprehensive knowledge of their environments. This knowledge was acquired through extensive observation of the local environment and continuous herding practices. Pastoralists’ wisdom about their local environment and adaptation strategies to climate change is essential for sustainable development. Thus, appreciation of pastoralists’ knowledge about their environment is also important for the integration of indigenous knowledge with the proper application of scientific approach to fit with the prevailing ecological potential of pastoral areas. Data were collected using focus group discussions, key informant interviews, and in-depth interviews. The in-depth interviews were conducted using a semi-structured questionnaire that was administered to 100 household heads with the age of above 50 years old. Respondents were randomly drawn from selected Pastoralists Associations (PAs) of two study districts. Data were analyzed using descriptive statistics as well as the logit model. The logit model was used to analyze the different coping strategies of pastoralists to overcome the failure of rain during different seasons. This was done by complementing pastoralists’ indigenous knowledge of time-series-based analysis across four seasons (Kerma, Gillal, Hagay, and Sugum) vs. the existing meteorological records. Forty years (from 1971 to 2011) of existing metrological data were used to compare the empirical evidence with pastoralists’ perceptions. Respondents mentioned that livestock number was the best indicator for evaluating rangeland condition in Afar region. The existing empirical evidence based on metrological data did not show any significant decline in precipitation for the last four decades between 1971 and 2011 as opposed to the perception of pastoralists where 80% of them reported a decline in precipitation. A one unit increase in labor force suggested about 16.1% decrease in the choice of livestock selling as coping strategy in Afar pastoral areas of North-East of Ethiopia. The non-intervened pastoral households had more preference (3.78%) to practice herd splitting than those pastoral households in the intervened district. Similarly, the non-intervened pastoral households had 4.43% more preference to use crop residue for livestock feeding than pastoral HHs in the intervened areas. Communities’ perceptions showed that livestock number was the best indicator of rangeland condition in the study area. Afar pastoralists’ observations with regard to temperature and precipitation trends over the last four decades greatly corresponded with the existing metrological-based empirical evidence. However, pastoralists’ perception in terms of reduced precipitation was not confirmed by the meteorological-based data records for the short rainy season (SRS). Afar pastoralists’ experience showed that the short rainy season was the best indicator for the occurrence of droughts as compared to other seasons in Afar. Our results suggest that most coping strategies are labor force demanding, and the situation worsens during the long rainy season (LRS). We suggest that differences in intervention between the study areas should not be overlooked as a policy tool in tackling the impact of climate change.

29 August 2016 in Agroforestry Systems
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Journal Article
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KFKenea Feyisa
Kenea Feyisa
SBSheleme Beyene
Sheleme Beyene
BMBekele Megersa
Bekele Megersa
MSMohammed Y. Said
Mohammed Y. Said
JLJan De Leeuw
Jan De Leeuw
AAAyana Angassa
Ayana Angassa

9 November 2016 in Ecological Processes
Verified
Journal Article
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MMinyahel Tilahun
Minyahel Tilahun
AAAyana Angassa
Ayana Angassa
AAAster Abebe
Aster Abebe
AMAlemayehu Mengistu
Alemayehu Mengistu
Community perception plays a significant role in rangeland resource management. Traditional rangeland management practices by the pastoral communities are based on accumulated knowledge in connection to their local environment. Pastoralism played a vital role in food production and sustaining its inhabitants in arid environment for millennia. However, national policies and development interventions in East African pastoral systems have often overlooked pastoralism while centered on the modernization of agricultural sector for economic development and poverty reduction. We used household survey, focus group discussion, key informant interview, and individual questionnaire to understand the perceptions and attitude of Afar pastoralists towards rangeland resource use and conservation practices, as well as impacts of development intervention on traditional rangeland resource use and conservation practices. The data were analyzed using index ranking and descriptive statistics. The results showed that livestock holding per household was higher on average (22.90 ± 2.27 Tropical Livestock Unit (TLU)) in the non-intervened woreda than in the intervened woreda (8.30 ± 3.85 TLU). Respondents mentioned that livestock productivity was adversely affected by a number of factors such as invasion of Prosopis juliflora (Dergi Hara), shrinkage in the capacity of rangelands (Beadu and Bebea’), and recurrent droughts. Scarcity of grazing resources attributed to the invasion of Dergi Hara and drought created livestock feed crisis with strong implication on the livelihood of pastoralists. Our results showed that the traditional resource management practices such as mobility, herd splitting, and diversification had a role to contribute to the improvement of rangeland management and conservation of biodiversity. Traditional rules and seasonal-based grazing patterns of riversides during drought were perceived as key elements for rangeland resource management and conservation of rangeland resources in the study area. Communities’ perception showed that the traditional practices of rangeland management systems are effective and environmentally sustainable. In contrast, inappropriate development interventions put rangelands under severe pressure. Although development interventions were aimed at improving the condition of Afar rangeland, they could not bring any enduring solution in terms of improvement of rangeland resources.