Food shortage is the main challenge of the semi-arid and arid regions of Ethiopia. Climate change is suggested the major deriver behind the problem (CSA, 2011). A study conducted by Kurukulasuriya et al, (2006) showed that high temperature and rainfall variability significantly influenced the agriculture sector in Ethiopia. At present, the food production system in Ethiopia is affected by climate changes because climate can directly influence the productivity of major crops (Wheeler and von Braun, 2013). Developing countries are more affected by climate change as the crop production system in these countries is directly depending on rainfall (IPCC, 2012). The study by Kurukulasuriya et al. (2006) and Muller et al. (2011) showed that climate change affected the economy of most countries in Africa. Studies also showed that climate change significantly influenced crops production in different countries (Muluneh et al. 2015). Hadgu et al, (2015) and Kassie et al. (2013) also reported that the livelihoods of people in Ethiopia were significantly affected by climate change. The majorities of people in Ethiopia are directly depending on rainfed production systems and are liable to impact of climate change. Change in rainfall amount and patterns in the future may negatively affect the small scale farming system in Ethiopia. According to Hadgu et al., (2015) extra warming projected in 2030s and 2050s may significantly affect the Ethiopian agricultural system. Thus, developing countries may be at the highest risk due to their low adaptive capacity to the changing climate. Crop failure is a frequent phenomenon in the rainfed system of semi-arid and arid areas of Ethiopia (Kassie et al., 2013). Cereal crops such as sorghum, teff and millet are dominant. The early offset of rainfall in the study area limits crop productivity. Water deficit occurs during the flowering and the grain filling stages of the crops that leads to significant yield reduction. As maize is highly sensitive to water deficit and heat stress yield is more affected as compared to the other cereal crops.
Maize (Zea mays L.) the major food crop well adapted in Ethiopia and in many Africa countries. Among the 22 maize-growing countries globally, sixteen are in Africa (Nuss and Tanumihardjo, 2011). Maize is called the queen of cereal crops because of the high yield potential. In Ethiopia, maize is majorly produced by small-scale farmers. CSA (2017). Maize ranks the second after teff (Eragrostis teff) in area coverage and the first in total production. The low cost of production and its high yield potential make maize the most popular crop in many countries (Nurudeen, 2011). In addition, maize is well adapted to a wide range of agroecologies (Paterson et al., 2009). The average national yield of maize in Ethiopia is 3900 kg ha-1 which is far below the world’s average (5660 kg ha-1). Studies showed that maize productivity has been declined from time to time (CSA), 2017) due to several factors such as frequent droughts, decline in soil fertility, poor agronomic practices, limited use of inputs, insufficient technologies, lack of credit, low seed quality, diseases, pests and weeds (Taffesse et al., 2011; Erkossa et al. 2007).
In Ethiopia, there are limited technologies that can improve maize productivity particularly in the arid and semi-arid areas (Bryan et al. (2009). Studies showed that adaptation strategies such as the use of improved maize cultivars and changing the current maize sowing date have been found successful to improve maize productivity (Nouria et al., 2017). Optimum fertilizer application was also effective to reduce effect of water and temperature stresses (Smith et al., 2020). He et al. (2018) studied the response of maize to fertilizer under future climate using the DSSAT technology and showed that soil physical quality, nutrient availability, and soil microbial diversity were significantly improved (Reynolds et al., 2014). Ma et al, (2018) also reported that the use of legume crops in rotation system reduced the adverse effects of climate change on crops in rainfed agriculture system. However, research findings regarding adaptation strategies for maize crop in Ethiopia is highly scarce.
Crop models have been used to predict crop phenology, growth, and yield in response to environmental factors. If models are properly calibrated, they are effective tools to study crops responses to environmental factors (Ruane et al., 2013). Crop models can identify options by increasing our understanding the impacts of climate change on crops. A study by Bhupinde (2018) showed that DSSAT technology has been used for different applications such as for soil fertility management, evaluating crop response to irrigation, analyzing yield gap, studying genotype by environment interaction, assessing effect of future climate on crops, for risk management, and identifying adaptation strategies. Li et al, (2015) used the DSSAT package to predict crop biomass, yield, soil nitrogen, and water balance under different environments and managements. However, crop models need to be calibrated in new environment and cropping practices. There are very limited experiences in using crop models to solve crop production problems in Ethiopia, Most studies emphasized on large-scale areas (Kassie et al., 2015) while some focused on economic aspects (Mideksa, 2010). Overall, there are very limited adaptation strategies in the arid and semi-arid areas of Ethiopia that address the impact of climate change on maize production (Alemayehu and Bewket, 2016). Therefore, assessing impact of projected climate change on maize production at local scale has significant implications for designing suitable adaptation strategies. Thus, this study was conducted (1) to calibrate and evaluate the CERES-maize model in DSSAT technology for simulating phenology and yield of maize (2) to assess how future climate will likely affect maize production in the study areas and (3) to identify potential adaptation strategies that can sustain maize production in the study region.