This study focuses on land cover and land management changes in relation to food security and environmental services in a semi-arid area of East Nusa Tenggara (ENT), Indonesia. The study was conducted in the Central Sumba District of ENT province. A classification and regression tree (CART) for land cover classification was analyzed using machine learning techniques through the implementation of the Google Earth Engine. A Focus Group Discussion (FGD) survey followed by in-depth interviews was conducted for primary data collection, involving a total of 871 respondents. The socio-economic data were statistically analyzed descriptively using non-parametric tests. The study showed that (1) there has been a substantial change in land use during the devolution era that has both positive and negative implications for food security and environmental services; (2) there has been population pressure in fertile and agricultural land as a direct impact of the development of city infrastructure; and (3) national intervention through the Food Estate program has fostered and shaped land use change and land management in the Central Sumba District. The study highlights the importance of the devolution spirit in aiding the management of limited arable/agricultural land in predominantly semi-arid areas to ensure food security and environmental services.