Aklilu Mekasha - Academia.edu (original) (raw)

Papers by Aklilu Mekasha

Research paper thumbnail of A population genomics approach to unlock the genetic potential of lablab (Lablab purpureus), an underutilized tropical forage crop

bioRxiv (Cold Spring Harbor Laboratory), Nov 26, 2023

Research paper thumbnail of Determinants of Sorghum Biomass Use for Livestock Feed Across Sorghum Growing Agroecological Zones in Ethiopia

Tropical and Subtropical Agroecosystems

Background. In mixed crop livestock farming systems in Ethiopia, sorghum stover and other crop re... more Background. In mixed crop livestock farming systems in Ethiopia, sorghum stover and other crop residues are a strategic livestock feed resource. Farmer’s decisions and intensity of use of sorghum stover for feed than other uses are closely associated with biophysical and socioeconomic characteristics. Objective. This study explores determinants of sorghum biomass uses for livestock feed in three major sorghum growing agroecological zones of Ethiopia. Methodology. Tobit and double hurdle models were run and likelihood ratio test was performed to select most suitable estimation technique. Result. Allocation of sorghum stover for feed showed a significant association with sorghum growing agro-ecological zones, highest in the lowland (86.73%) and the lowest in highland sorghum growing agroecological area (61.75%). Econometric model result revealed that among other factors; availability of feed from grazing and other crop residues had a negative effect on decision to use and intensity o...

Research paper thumbnail of Analysis of Climate Variability and Its Interconnection with Major Crops Production in the South Gondar Zone, Amhara National Regional State, Ethiopia

Research paper thumbnail of Measurements in Pasture and Forage Cropping Systems

Preface i In tro d u ctio n 1 G row th a n d d evelopm ent 4 M easu rem en ts in p astu re a n d ... more Preface i In tro d u ctio n 1 G row th a n d d evelopm ent 4 M easu rem en ts in p astu re a n d grass-legum e m ixed cro p p in g systems 21 H andling sam ples 35 Sam ple exercise 38 A cknow ledgem ents 3 9

Research paper thumbnail of Farmers’ participatory forage cowpea (Vigna unguiculata) variety selection in the mid Rift Valley areas of Ethiopia

Cowpea is one of the most important crops of dryland farmers with wide geneticdiversity for growt... more Cowpea is one of the most important crops of dryland farmers with wide geneticdiversity for growth habit; biomass and bean seed yield, resistance/ tolerance to bioticand abiotic stresses, and responsiveness to inputs. In the present study, farmers’participatory forage cowpea variety evaluation and selection was carried out (using ahierarchical decision making Multi Criteria Analysis model) at three districts (Adama,Boset and Mieso) in the mid Rift Valley areas of Ethiopia. Farmers compared and ratedsix selection criteria and four candidate forage type cowpea varieties pairwise. Theresults showed that, on average, farmers rated resistance / tolerance to drought as mostimportant selection criterion followed by higher bean seed and biomass yields. Amongthe candidate varieties, farmers rated variety ILRI-9334 as better in terms of resistance/tolerance to diseases, insects and droughts. On the other hand, variety ILRI-11110 wasrated as early maturing, whereas variety ILRI-9352 was descri...

Research paper thumbnail of Location and plant spacing affect biomass yield and nutritional value of pigeon pea forage

Agronomy Journal, 2021

An experiment was conducted to evaluate the effects of row spacing (RS) and interplant spacing (I... more An experiment was conducted to evaluate the effects of row spacing (RS) and interplant spacing (IPS) on the yield of total biomass, leaf, and edible twigs, and nutritive value of pigeon pea,(Cajanus cajan L. Millsp.) at three locations in the Rift Valley area of Ethiopia, using a randomized completed block design with three replications in 3 × 3 factorial arrangement; three RS ( 25, 50, and 75 cm) and three IPS (15, 30, and 45 cm). Row spacing × IPS of 25 × 30 cm and 50 × 15 cm, gave greater total biomass yield than the other RS and IPS combinations. A similar result was found for edible plant yield. At Hawassa the greater leaf CP was found for the wider IPS of 45 cm than the narrower IPS of 30 cm (318 Vs. 303 g kg-1 ). At Wondo-Genet, the greater leaf in vitro digestible organic matter (597 Vs. 582 g kg-1 ) was found for the wider RS of 75 cm than narrower RS. Similar to leaf, a better nutritional value of edible twigs was found for a wider RS and IPS than narrower RS and IPS at Hawassa and Wondo-Genet. In contrast at Aliyu-Amab, a better nutritional value of edible twigs was found for narrower RS and IPS than the wider spacing. Thus, it can be concluded that RS × IPS of 25 × 30 cm or 50 × 15 cm are advisable for pigeon pea forage production.

Research paper thumbnail of Temporal Change in Relative Availability/ Contribution of Different Livestock Feed Resources to the Total Feeds Available to Livestock Keepers in the Mixed Crop-livestock Highlands of Ethiopia: The Case of Household Perception in Tiyo District, Arsi Zone

Journal of Scientific Research and Reports, 2016

Research paper thumbnail of Perception of climate extreme trends over three Ethiopian eco-environments: Comparison with records and analysis of determinants

Journal of Agricultural Biotechnology and Sustainable Development, 2016

Research paper thumbnail of Trends in daily observed temperature and rainfall extremes over three Ethiopian eco-environments

International Journal of Climatology

Ethiopia has wide eco-environmental diversity ranging from extreme heat at one of the lowest plac... more Ethiopia has wide eco-environmental diversity ranging from extreme heat at one of the lowest places in the world to one of the coolest summits in Africa. Associated with this environmental diversity and climate change, climatic extremes are expected to change over time and also vary across eco-environments in the country. This study was conducted to examine the trends of past precipitation and temperature extremes over three eco-environments in Ethiopia. The study involved analysis of 20 extreme indices computed from daily temperature and precipitation data spanning over 42 years (1967-2008). The climate data were obtained from 11 stations selected from three major eco-environments (pastoral, agropastoral and highland). The results indicated positive trends for maximum value of the maximum temperature (TXx), warm days (TX90p), warm nights (TN90p) and warm spell duration indicators (WSDI) and negative trends for cool days (TX10p), cool nights (TN10p) and cold spell duration indicators (CSDI) in more than 8 of the 11 stations studied. However, most of the trends were not significant at many of the stations and the significant trends were not uniquely differentiated by eco-environments. Unlike temperature extremes, precipitation extreme trends showed high variability among nearby stations within eco-environments and were not significant at many of the stations studied. It is concluded that trends of temperature and precipitation extremes vary considerably among stations located within a given eco-environment indicating that the response of local climate to global warming could be different in physiographically diverse regions.

Research paper thumbnail of Trends in daily observed temperature and precipitation extremes over three Ethiopian eco-environments

International Journal of Climatology, 2013

Research paper thumbnail of Modeling the response of tropical highland herbaceous grassland species to climate change: The case of the Arsi Mountains of Ethiopia

Biological Conservation, 2013

Global warming is forcing plant and animal species to respond either through pole-ward or upslope... more Global warming is forcing plant and animal species to respond either through pole-ward or upslope migration to adjust to temperature increases, and grassland communities are not an exception to this phenomenon. In this study, we modeled the response of herbaceous species of grasslands within the Arsi Mountains in Ethiopia under no-migration and with migration scenarios to the projected 4.2°C increase of temperature by 2090 (under the A2 emission scenario). For 67 species of grasses and legumes, we determined the current and predicted altitudinal limits and calculated current and projected area coverage using a Digital Elevation Model. The results indicated that the projected warming significantly reduced altitudinal ranges and habitat areas of all the species studied. All the studied species faced range contraction and habitat loss with range shift gaps among forty two species under the no-migration scenario. With the migration scenario, however, the forty two species with range shift gaps are predicted to benefit from at least some habitat area retention. Between growth forms, legumes are predicted to lose significantly more habitat area than grasses under the no-migration scenario while no significant difference in habitat area loss is predicted under the migration scenario. It can be concluded that management options are required to facilitate upslope species migration to survive under the warming climate. This could involve leaving suitable dispersal corridors and assisted colonization depending on species behavior and level of extinction risk predicted under the projected warming.

Research paper thumbnail of Seeding rate effects on forge productivity and nutritive value of sorghum

Research paper thumbnail of Inter-connection between land use/land cover change and herders’/farmers’ livestock feed resource management strategies: a case study from three Ethiopian eco-environments

We assessed land use/land cover changes from remotely sensed satellite imagery and compared this ... more We assessed land use/land cover changes from remotely sensed satellite imagery and compared this with community perceptions on availability/use of livestock feed resources and feed deficit management strategies since the 1973s in three districts representing the pastoral, agro-pastoral and mixed croplivestock eco-environments of Ethiopia. We found that land use/land cover changes are proceeding in all eco-environments and that transitions are from grasslands, and forest lands to bush/shrub lands and crop lands in the pastoral site (Liben), from bush/shrub lands and grasslands to crop lands in agro-pastoral site (Mieso) and from bush/shrub lands, forest lands and grasslands to crop lands in the mixed crop-livestock site (Tiyo). The changes significantly affected livestock feed resources and feed deficit management strategies available to households. Over the last 30-40 years, grazing resources available to livestock keepers have been declining with resultant increase in the contribution of crop residues and other feeds from crop lands (weeds and crop thinnings) as compared to feeds from grasslands. The feed deficit management strategies of households are also changing significantly from mobility to herd management and feed conservation in the pastoral areas; from mobility to feed conservation and purchasing of feed in the agro-pastoral areas and from transhumance to feed conservation and purchase of feed in the mixed crop-livestock areas. Hence feed resources and their availability vary with time and eco-environments indicating the need for the development of eco-environment/site specific feed management strategies in order to support productive stock in the study areas and similar eco-environments.

Research paper thumbnail of A population genomics approach to unlock the genetic potential of lablab (Lablab purpureus), an underutilized tropical forage crop

bioRxiv (Cold Spring Harbor Laboratory), Nov 26, 2023

Research paper thumbnail of Determinants of Sorghum Biomass Use for Livestock Feed Across Sorghum Growing Agroecological Zones in Ethiopia

Tropical and Subtropical Agroecosystems

Background. In mixed crop livestock farming systems in Ethiopia, sorghum stover and other crop re... more Background. In mixed crop livestock farming systems in Ethiopia, sorghum stover and other crop residues are a strategic livestock feed resource. Farmer’s decisions and intensity of use of sorghum stover for feed than other uses are closely associated with biophysical and socioeconomic characteristics. Objective. This study explores determinants of sorghum biomass uses for livestock feed in three major sorghum growing agroecological zones of Ethiopia. Methodology. Tobit and double hurdle models were run and likelihood ratio test was performed to select most suitable estimation technique. Result. Allocation of sorghum stover for feed showed a significant association with sorghum growing agro-ecological zones, highest in the lowland (86.73%) and the lowest in highland sorghum growing agroecological area (61.75%). Econometric model result revealed that among other factors; availability of feed from grazing and other crop residues had a negative effect on decision to use and intensity o...

Research paper thumbnail of Analysis of Climate Variability and Its Interconnection with Major Crops Production in the South Gondar Zone, Amhara National Regional State, Ethiopia

Research paper thumbnail of Measurements in Pasture and Forage Cropping Systems

Preface i In tro d u ctio n 1 G row th a n d d evelopm ent 4 M easu rem en ts in p astu re a n d ... more Preface i In tro d u ctio n 1 G row th a n d d evelopm ent 4 M easu rem en ts in p astu re a n d grass-legum e m ixed cro p p in g systems 21 H andling sam ples 35 Sam ple exercise 38 A cknow ledgem ents 3 9

Research paper thumbnail of Farmers’ participatory forage cowpea (Vigna unguiculata) variety selection in the mid Rift Valley areas of Ethiopia

Cowpea is one of the most important crops of dryland farmers with wide geneticdiversity for growt... more Cowpea is one of the most important crops of dryland farmers with wide geneticdiversity for growth habit; biomass and bean seed yield, resistance/ tolerance to bioticand abiotic stresses, and responsiveness to inputs. In the present study, farmers’participatory forage cowpea variety evaluation and selection was carried out (using ahierarchical decision making Multi Criteria Analysis model) at three districts (Adama,Boset and Mieso) in the mid Rift Valley areas of Ethiopia. Farmers compared and ratedsix selection criteria and four candidate forage type cowpea varieties pairwise. Theresults showed that, on average, farmers rated resistance / tolerance to drought as mostimportant selection criterion followed by higher bean seed and biomass yields. Amongthe candidate varieties, farmers rated variety ILRI-9334 as better in terms of resistance/tolerance to diseases, insects and droughts. On the other hand, variety ILRI-11110 wasrated as early maturing, whereas variety ILRI-9352 was descri...

Research paper thumbnail of Location and plant spacing affect biomass yield and nutritional value of pigeon pea forage

Agronomy Journal, 2021

An experiment was conducted to evaluate the effects of row spacing (RS) and interplant spacing (I... more An experiment was conducted to evaluate the effects of row spacing (RS) and interplant spacing (IPS) on the yield of total biomass, leaf, and edible twigs, and nutritive value of pigeon pea,(Cajanus cajan L. Millsp.) at three locations in the Rift Valley area of Ethiopia, using a randomized completed block design with three replications in 3 × 3 factorial arrangement; three RS ( 25, 50, and 75 cm) and three IPS (15, 30, and 45 cm). Row spacing × IPS of 25 × 30 cm and 50 × 15 cm, gave greater total biomass yield than the other RS and IPS combinations. A similar result was found for edible plant yield. At Hawassa the greater leaf CP was found for the wider IPS of 45 cm than the narrower IPS of 30 cm (318 Vs. 303 g kg-1 ). At Wondo-Genet, the greater leaf in vitro digestible organic matter (597 Vs. 582 g kg-1 ) was found for the wider RS of 75 cm than narrower RS. Similar to leaf, a better nutritional value of edible twigs was found for a wider RS and IPS than narrower RS and IPS at Hawassa and Wondo-Genet. In contrast at Aliyu-Amab, a better nutritional value of edible twigs was found for narrower RS and IPS than the wider spacing. Thus, it can be concluded that RS × IPS of 25 × 30 cm or 50 × 15 cm are advisable for pigeon pea forage production.

Research paper thumbnail of Temporal Change in Relative Availability/ Contribution of Different Livestock Feed Resources to the Total Feeds Available to Livestock Keepers in the Mixed Crop-livestock Highlands of Ethiopia: The Case of Household Perception in Tiyo District, Arsi Zone

Journal of Scientific Research and Reports, 2016

Research paper thumbnail of Perception of climate extreme trends over three Ethiopian eco-environments: Comparison with records and analysis of determinants

Journal of Agricultural Biotechnology and Sustainable Development, 2016

Research paper thumbnail of Trends in daily observed temperature and rainfall extremes over three Ethiopian eco-environments

International Journal of Climatology

Ethiopia has wide eco-environmental diversity ranging from extreme heat at one of the lowest plac... more Ethiopia has wide eco-environmental diversity ranging from extreme heat at one of the lowest places in the world to one of the coolest summits in Africa. Associated with this environmental diversity and climate change, climatic extremes are expected to change over time and also vary across eco-environments in the country. This study was conducted to examine the trends of past precipitation and temperature extremes over three eco-environments in Ethiopia. The study involved analysis of 20 extreme indices computed from daily temperature and precipitation data spanning over 42 years (1967-2008). The climate data were obtained from 11 stations selected from three major eco-environments (pastoral, agropastoral and highland). The results indicated positive trends for maximum value of the maximum temperature (TXx), warm days (TX90p), warm nights (TN90p) and warm spell duration indicators (WSDI) and negative trends for cool days (TX10p), cool nights (TN10p) and cold spell duration indicators (CSDI) in more than 8 of the 11 stations studied. However, most of the trends were not significant at many of the stations and the significant trends were not uniquely differentiated by eco-environments. Unlike temperature extremes, precipitation extreme trends showed high variability among nearby stations within eco-environments and were not significant at many of the stations studied. It is concluded that trends of temperature and precipitation extremes vary considerably among stations located within a given eco-environment indicating that the response of local climate to global warming could be different in physiographically diverse regions.

Research paper thumbnail of Trends in daily observed temperature and precipitation extremes over three Ethiopian eco-environments

International Journal of Climatology, 2013

Research paper thumbnail of Modeling the response of tropical highland herbaceous grassland species to climate change: The case of the Arsi Mountains of Ethiopia

Biological Conservation, 2013

Global warming is forcing plant and animal species to respond either through pole-ward or upslope... more Global warming is forcing plant and animal species to respond either through pole-ward or upslope migration to adjust to temperature increases, and grassland communities are not an exception to this phenomenon. In this study, we modeled the response of herbaceous species of grasslands within the Arsi Mountains in Ethiopia under no-migration and with migration scenarios to the projected 4.2°C increase of temperature by 2090 (under the A2 emission scenario). For 67 species of grasses and legumes, we determined the current and predicted altitudinal limits and calculated current and projected area coverage using a Digital Elevation Model. The results indicated that the projected warming significantly reduced altitudinal ranges and habitat areas of all the species studied. All the studied species faced range contraction and habitat loss with range shift gaps among forty two species under the no-migration scenario. With the migration scenario, however, the forty two species with range shift gaps are predicted to benefit from at least some habitat area retention. Between growth forms, legumes are predicted to lose significantly more habitat area than grasses under the no-migration scenario while no significant difference in habitat area loss is predicted under the migration scenario. It can be concluded that management options are required to facilitate upslope species migration to survive under the warming climate. This could involve leaving suitable dispersal corridors and assisted colonization depending on species behavior and level of extinction risk predicted under the projected warming.

Research paper thumbnail of Seeding rate effects on forge productivity and nutritive value of sorghum

Research paper thumbnail of Inter-connection between land use/land cover change and herders’/farmers’ livestock feed resource management strategies: a case study from three Ethiopian eco-environments

We assessed land use/land cover changes from remotely sensed satellite imagery and compared this ... more We assessed land use/land cover changes from remotely sensed satellite imagery and compared this with community perceptions on availability/use of livestock feed resources and feed deficit management strategies since the 1973s in three districts representing the pastoral, agro-pastoral and mixed croplivestock eco-environments of Ethiopia. We found that land use/land cover changes are proceeding in all eco-environments and that transitions are from grasslands, and forest lands to bush/shrub lands and crop lands in the pastoral site (Liben), from bush/shrub lands and grasslands to crop lands in agro-pastoral site (Mieso) and from bush/shrub lands, forest lands and grasslands to crop lands in the mixed crop-livestock site (Tiyo). The changes significantly affected livestock feed resources and feed deficit management strategies available to households. Over the last 30-40 years, grazing resources available to livestock keepers have been declining with resultant increase in the contribution of crop residues and other feeds from crop lands (weeds and crop thinnings) as compared to feeds from grasslands. The feed deficit management strategies of households are also changing significantly from mobility to herd management and feed conservation in the pastoral areas; from mobility to feed conservation and purchasing of feed in the agro-pastoral areas and from transhumance to feed conservation and purchase of feed in the mixed crop-livestock areas. Hence feed resources and their availability vary with time and eco-environments indicating the need for the development of eco-environment/site specific feed management strategies in order to support productive stock in the study areas and similar eco-environments.