MODELING FACTORS INFLUENCING BARLEY YIELD IN ETHIOPIA: AUGMENTED COBB-DOUGLAS PRODUCTION FUNCTION APPROACH

Barley production in Ethiopia is constrained by climatic and non-climatic factors. The objective of this study was to examine the influence of climate change and non-climatic inputs on barley yield in Ethiopia. The study employed an augmented Cobb-Douglas production function approach to model factors influencing barley yield in the country. The results revealed that short/belg-season rainfall and temperature variables showed positive relationship with barley yield, having minimal positive impact on yield of barley. The positive elasticity of short/belg-season rainfall is justified by the fact that short duration barley crops are grown in the highlands of Bale, North Central Shewa, and Wollo zones contributing less than 10% of total grain production.Conversely, long/main-season rainfall showed negative impact on yield of barley, which due to extreme rain events such as high rainfall above optimum requirement of the crop as well as scarcity of rainfall in some pocket areas. The result infers that cultivation of barley in Ethiopia moderately depends on rainfall. Among the non-climatic variables, irrigated land area under barley cultivation, fertilizer quantity used, and improved barley seed used had positive impact on barley yield. Fertilizer and improved seed inputs had positive and significant impact on barley yield. The result implies that barley yield is highly responsive to use of fertilizer and improved barley seed inputs and moderately responsive to irrigation input. Conversely, land area cultivated under barley crop had negative impact on barley yield, although not significant

Impact of climate change on yields and output supply responses of selected cereal crops in Ethiopia

Climate change affects agricultural production and productivity in sub-Saharan Africa, including Ethiopia, where it poses some threats to sustainable economic growth and ag-ricultural development. As studies conducted on the impact of climate change on crop production are limited, this study analyzed the impacts of the changes in climate on yields and output supply responses of teff, wheat and maize crops in Ethiopia. The study employed time series secondary data on selected variables over the period of 1981 to 2018. The data were collected from various reputable sources such as the Ethio-pian CSA, NMA, and FAO data set (FAOSTAT). The study adopted Cobb-Douglas Pro-duction Function and Autoregressive Distributed Lag (ARDL) modeling approaches. The impacts of climate change on crop yields and output was estimated using key cli-mate parameters (minimum and maximum temperature and short- and long- season rainfalls). The results of Production Function analysis on the impact of climate variables on yield of cereal crops revealed that long-season rainfall have negative (-0.352, -0.498, and -0.429) and significant (at 1% and 5% levels) impact on yields of teff, wheat and maize crops, respectively. Maximum temperature also had negative (-2.810 & -3.681) and sig-nificant (at 10% level) impact on the yields of wheat and maize crops while it had posi-tive (0.372) and significant (at 10% level) impact on teff yield. Equally, the impact of climatic variables on crop output supply responses was estimated based on crop season temperature and short- and long-season rainfalls. The results indi-cated that changes in short- and long-season rainfalls had negative (-0.453 and -0.077) and significant (at 1% level) impact on wheat and maize outputs in their first lag order. The results also demonstrated that crop growing period mean temperature had negative (-2.88 and -10.70) and significant (at 1% and 5% levels) impacts on wheat and maize outputs in their first lag orders. Although temperature and long-season rainfall parame-ters showed negative impact on teff output, their impacts were minimal as they were statistically insignificant. Conversely, carbon dioxide (CO2) showed positive (4.76 and 2.256) and significant (at 5% and 1% level) impact on teff and wheat outputs in their first lag orders. This signified that teff and wheat outputs were positively responsive to an increase in CO2 concentration. Forecasted future changes in temperature and rainfall variables showed increasing trend in mean temperature (rise from -4.850C to 0.1950C by 2080) in teff growing belt while future changes in rainfall (both short- and long-season rainfalls) showed a decreasing trend in teff (from -0.06mm to -1.58mm), wheat (from -0.11mm to -1.3mm), and maize (from -0.01mm to -0.17mm) growing belts by 2080. However, the projected future changes in the yields of wheat, maize and teff are positive over the selected scenarios. By 2080, yield of wheat would increase by 237% while those teff and maize would increase by48% and 10% respectively. In conclusion, rainfall and temperature parameters were found to increase yield level and variability for wheat crop. However, rainfall and temperature parameters were indi-vidually found to have adverse effects on yield of teff and maize crops. Unless some abatement measures are taken on increasing CO2 emission, the rise in temperature and the decrease in seasonal rainfall will continue and this will negatively affect cereal crop yields. It is therefore recommended that there is the need to design and implement adap-tation strategies that reverse and mitigate the risks of changing climate. Development of early maturing and stress tolerant crop varieties as well as supporting research and ex-tension tasks becomes imperative.Agriculture and  Animal HealthPh. D. (Agriculture

IMPACT OF CLIMATE CHANGE ON YIELDS OF WHEAT IN ETHIOPIA: AN AUGMENTED COBB-DOUGLAS PRODUCTION FUNCTION APPROACH

The study analyzed the impact of climate change on yields of wheat crop in Ethiopia by employing Cobb-Douglas Production Function Approach using time series data for the period 1981 – 2018. The study confirmed that long-season rainfall and crop growing season maximum temperature have negative and significant effects on wheat yield. The result implies that a rise in maximum temperature during crop growing period and variation in long-season rainfall could have adverse impact on yield of wheat crop. The findings further showed that fertilizers, improved seed, and irrigation applied on wheat crop have all positive and significant impact on yield of wheat, implying that use of fertilizer, improved seed and irrigation inputs have vital role in increasing yields of wheat crop. Conversely, the study indicated that land area cultivated under wheat cropping showed negative and significant impact on yield of wheat crop, implying that any area expansion under wheat crop production would have negative impact. In view of the findings of the study, it is recommended that adaptation strategies that could offset the adverse effects of climate change should be designed and adopted. An increased use of irrigation is recommended, particularly in potential lowland areas to mitigate the adverse effect of climate sensitivity on wheat crop. Use of improved wheat seed varieties of short duration and tolerant to warm and moisture stress conditions are recommended to increase productivity and production of wheat crop. Increased use of fertilizers in cooler mid and highland areas can be another option to increase the productivity of wheat crop in Ethiopia

An Augmented Cobb-Douglas Production Function Modeling of the Impact of Climate Change on Maize Yields in Ethiopia

Climate change remains a major problem confronting agricultural productivity in Ethiopia. Maize and some other cereal crops are susceptible to climatic parameters. This study analyzed the impacts of some climatic variables on the yields of maize crops in Ethiopia using the 1981-2018 dataset. Maize production in Ethiopia is adversely affected by climate change. The augmented Cobb-Douglas Production function was used for data analyses. The results showed that the parameters of long-season rainfall, short-season rainfall, and mean maximum temperature show a negative sign and are statistically significant (p<0.05). In contrast, the minimum temperature shows a positive sign. In addition, the parameters of the quantity of fertilizer and improved seed used in maize production have a positive and significant impact on the yields of maize (p<0.10). However, the land area's elasticity coefficient shows a negative and statistically significant sign. It was concluded that changes in climatic parameters, such as an increase in short-season and long-season rainfall and an increase in maximum temperature, would reduce maize productivity. Therefore, utilizing effective climate change adaptation measures promises to enhance maize productivity in Ethiopia

Determinants of Barley Output Supply Response in Ethiopia: Application of Ardl Bound Cointegration Approach

This study investigated barley output supply response determinant factors in Ethiopia. An ARDL bound test approach was employed as method using secondary data from 1981-2020. The study demonstrated that barley output supply was affected positively and significantly by zero-order lagged seasonal rainfall and crop growing period temperature. The study supports the findings of researchers who reported that warming temperature followed by an increase in the amount of rainfall had a positive impact on barley output supply. The positive impact of temperature was induced because of a rise in the ocean and earth’s surface average temperature, causing more evaporation that increases overall rainfall while reaching over the highland areas. Studies confirm that ENSO and moist winds coming from the Atlantic and Indian Oceans influence the occurrence of rainfall in the western, southeastern, central, and northern highlands of Ethiopia. The study further exhibited that CSMRR and CGPMT had a positive effect on barley output both in the long-run and short-run, implying that climate parameters have minimal effect on barley production. Nonclimatic variables demonstrated that both lagged and current year’s producer prices had a positively significant effect on barley output supply in both the long-run and short-run, implying that barley output supply is highly responsive to any price incentive strategies announced before re-allocation of the area towards barley cultivation. Conversely, the study explored that use of fertilizer in first-order lag had negatively significant impact on barley output supply in both seasons; implying that increased use of fertilizer in lagged period may reduce barley output as a result of inappropriate fertilizers application by farmers. The results generated by this study are useful addendum to the repository of knowledge on elasticity of crop supply at an aggregate level, which can be used in designing strategies and measures for mitigation and adaptation of climate change

Maize Output Supply Response to Climatic and Other Input Variables in Ethiopia

Climate change is among the major challenges to sustainable agricultural production in Ethiopia. Production of cereal crops, especially maize, is very responsive to changes in rainfall and temperature, as climatic parameters influencing productivity. This paper analyzes how climatic and other variables affect the supply of maize in Ethiopia. The data were obtained from secondary sources and cover the period 1981–2018. Data were analyzed using the Autoregressive Distributed Lag (ARDL) approach. The Akaike Information Criterion (AIC), Schwarz Information Criterion (SIC), and Hannan-Quinn Information Criterion (HQ) were used to select the optimum number of lags. In order to detect whether unit root is present in the series, Augmented Dickey-Fuller (ADF) and Philips-Perron (PP) tests were carried out. The presence of long-run equilibrium was found between maize output and temperature, rainfall, and other included variables. The results show that, in both the long and shortrun, all included climatic variables had a negative relationship with maize output supply, although temperature showed statistical insignificance (P>0.10). The result showed that maize crops are highly sensitive to extremes of rainfall – both shortage in the initial growing period and excessin the vegetative and fruiting stages. It was concluded that farmers face climate-related risk due to variations, particularly in rainfall. Therefore, farmers should adapt by using short-duration and climate-tolerant varieties of maize, along with engagement with eco-friendly production systems

Maize Output Supply Response to Climatic and Other Input Variables in Ethiopia

Climate change is among the major challenges to sustainable agricultural production in Ethiopia. Production of cereal crops, especially maize, is very responsive to changes in rainfall and temperature, as climatic parameters influencing productivity. This paper analyzes how climatic and other variables affect the supply of maize in Ethiopia. The data were obtained from secondary sources and cover the period 1981–2018. Data were analyzed using the Autoregressive Distributed Lag (ARDL) approach. The Akaike Information Criterion (AIC), Schwarz Information Criterion (SIC), and Hannan-Quinn Information Criterion (HQ) were used to select the optimum number of lags. In order to detect whether unit root is present in the series, Augmented Dickey-Fuller (ADF) and Philips-Perron (PP) tests were carried out. The presence of long-run equilibrium was found between maize output and temperature, rainfall, and other included variables. The results show that, in both the long and shortrun, all included climatic variables had a negative relationship with maize output supply, although temperature showed statistical insignificance (P>0.10). The result showed that maize crops are highly sensitive to extremes of rainfall – both shortage in the initial growing period and excessin the vegetative and fruiting stages. It was concluded that farmers face climate-related risk due to variations, particularly in rainfall. Therefore, farmers should adapt by using short-duration and climate-tolerant varieties of maize, along with engagement with eco-friendly production systems