Managing Land Carrying Capacity: Key to Achieving Sustainable Production Systems for Food Security

Many previous studies have estimated the carrying capacity and feasible planetary boundaries for humankind. However, less attention has been given to how we will sustainably feed 9 billion people in 2050 and beyond. Here, we review the major natural resources that limit food production and discuss possible options, measures, and strategies to sustainably feed a human population of 9 billion in 2050 and beyond. Currently, food production greatly depends on external inputs, e.g., irrigation water and fertilizers, but these approaches are not sustainable. Due to the unbalanced distribution of global natural resources and large regional differences, urbanization expansion causes important areas to face more serious arable land resource shortages. Hence, sustainably feeding 9 billion people in 2050 and beyond remains an immense challenge for humankind, and this challenge requires novel planning and better decision-making tools. Importantly, the measures and strategies employed must be region-/country-specific because of the significant differences in the socioeconomic characteristics and natural environmental carrying capacity in different parts of the world. Considering the impact of unexpected extreme events (e.g., a global pandemic and war) in the future, the food trade and translocation of goods will also face challenges, and the strategies and decision-making processes employed must consider the possible influences at both regional and global scales.