Land Use Scenarios and Their Effect on Potential Crop Production: The Case of Gambella Region, Ethiopia

Abstract

Agricultural intensification and cropland expansion are the key policies to increase food production in Ethiopia. Gambella is one of the regions in Ethiopia which is highly suitable for agriculture; however, the local people still face food shortages. We therefore investigated the potential for intensification and cropland expansion. In this study, we developed land use scenarios of agricultural intensification and expansion and analysed their effect on potential crop production in the region and estimated the population that could be nourished as a result. We distinguished between different degrees of intensification, ranging from low input rainfed to high input irrigated agriculture and different degrees of expansion, considering the best 30% or 50% of land to be utilized for expansion. While the results reveal that irrigation had almost no effect on potential yields, they also show that the potential calorie production in all scenarios far exceeds the current and possible future caloric requirements of Gambella’s population. For example, for the top 50% expansion scenario, calorie production increased by +428% for the low input and by +1092% for the high input scenarios. Thus, Gambella could nourish up to 21 million people and serve as a bread basket for the entire country, which could improve national food security.

Spatiotemporal variability and trends in rainfall and temperature in Alwero watershed, western Ethiopia

“…Mean annual rainfall is about 1200 mm. Mean annual temperature is 26.7 °C (Degife et al 2019). The level of natural resource use is low due to sparse population density.…”

“…and rice (Oryza sativa L.) are major crops grown in the area (Yitbarek et al 2017). From these, maize and sorghum are the dominant in terms of production (Degife et al 2019) and consumption (Dorosh and Rashid 2013).…”

Climate change impacts on potential maize yields in Gambella Region, Ethiopia

“…Maize yields have doubled from about 1.6 t ha −1 during the early 1990s to 3.7 t ha −1 in recent years (Van Dijk et al 2020). In 2016/2017, maize crop accounts for 57% of Gambella region's crop production by smallscale farmers and 56% of the region's harvested area (Degife et al 2019). The following study comprises a representative selection of climate change impact scenarios to show the range of possible futures for different representative concentration pathways (RCPs).…”

“…in the east to 500-900 m in the center and 300-500 m in the west (Woube 1999). The mean annual temperature of the region varies from 17.3 to 28.3°C and the annual precipitation of the region varies from 800 to 1200 mm (Degife et al 2019). The region is highly suitable for agriculture (Zabel et al 2014).…”

“…In this study, we assume that agricultural land in Gambella will expand into the not-yet-used legally available land for agricultural expansion. Therefore, all our results refer to all current cropland area in addition to the Top 50 expansion scenario according to Degife et al (2019) and Zabel et al (2019). The scenario assumes the use of today's cropland in addition to the best (in terms of highest potential yields) 50% expansion area.…”