The pace of change in land use and cover in Ethiopia depends on three main factors that cause pressure on agriculture land: resettlement programmes, population growth and increasing agricultural investments. Gambella is one of the regions of Ethiopia that attracts large-scale agricultural investments that extensively drive land use and cover changes in the region. The aim of this study is to examine the rate, extent and distribution of various land use and cover changes in Gambella Regional State, Ethiopia, from 1987 to 2017. The analysis is mainly based on Landsat 5 and Sentinel 2A satellite images and fieldwork. Two Landsat Thematic Mapper and a Sentinel 2A image were used for determining the maximum likelihood of land use/cover classification. The results show that farmland decreased by 26 km2 from 1987 to 2000; however, during the last two decades, agricultural land area increased by 599 km2, mainly at the cost of tropical grasslands and forests. We found that areas cultivated by smallholder farmers increased by 9.17% from 1987 to 2000. However, small-scale farm activities decreased by 7% from 2000 to 2017. Areas cultivated by large-scale state farms totalled 202 km2 in 1987; but by 2000, this large-scale state farming had been completely abandoned by the state, and as a result, its land use has decreased to zero. Despite this, in 2017 large-scale farming increased to 746 km2. In addition, Gambella National Park, which is the nation's largest national park and ecosystem, was also largely affected by Land Use and Land Cover changes. The conversion of savannah/tropical grasslands to agricultural farmland has caused varied and extensive environmental degradation to the park. The Land Use and Land Cover changes in the Gambella region are discussed on the basis of underlying socioeconomic factors.

Changing climate conditions are supposed to have particularly strong impacts on agricultural production in the tropics with strong implications on food security. Ethiopia’s economy is profoundly dominated by agriculture, contributing to around 40% of the gross domestic product. Thereby, Ethiopia is one of the most vulnerable countries to the impact of climate change and has a wide gap in regional climate change impact studies. In this study, we systematically investigate climate change impacts on yields for the Gambella region in Ethiopia, exemplarily for maize. Here, we show how yields change until 2100 for RCPs 2.6, 4.5, and 8.5 from a climate model ensemble under rainfed and irrigated conditions. While rainfed yields decrease by 15% and 14% respectively for RCPs 2.6 and 4.5, yields decrease by up to 32% under RCP 8.5. Except for RCP 8.5, yields are not further decreasing after 2040–2069. We found that temperature increase, changing soil water availability, and atmospheric CO2 concentration have different effects on the simulated yield potential. Our results demonstrate the dominance of heat response under future climate conditions in the tropical Gambella region, contributing to 85% of total yield changes. Accordingly, irrigation will lose effectiveness for increasing yield when temperature becomes the limiting factor. CO2, on the other hand, contributes positively to yield changes by 8.9% for RCP 8.5. For all scenarios, the growing period is shorted due to increasing temperature by up to 29 days for RCP 8.5. Our results suggest that new varieties with higher growing degree days are primarily required to the region for adapting to future climate conditions.

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.

Ethiopian government uses agricultural investment as one of the most important and effective strategies for economic growth, food security, and poverty reduction in the country. Since the mid-2000s, government has awarded millions of hectares of fertile land to foreign companies. This study explores the impact of large-scale agriculture investment and its consequences to local livelihoods in Gambella Region, Ethiopia. Gambella people's survival and their identity are strongly tied to the land and the rivers that run through it. However, currently, foreign and local investors grab the farm area on an industrial scale and that deprives their livelihoods and increases food insecurity. Moreover, large land acquisition has been tremendous environmental devastation in region such as deforestation, biodiversity depletion, and wetlands drained. Meanwhile, socially, people are largely dependent on international food aid and financial assistance. On the other hand, Large Scale Land Acquisitions (LSLA) lead to forced displacement and "villagization" as a result that smallholder farmers are displaced, pastoralists lose the grazing land, and local people lose incomes and livelihoods. Lastly, in the region, due to land corruption, lack of good governance and transparency, the natural resources are depleted and societies become food insecure.Therefore, Ethiopian government's strategies are on the verge of falling unless integrated approach is not implemented.