Changes in and prediction of land carrying capacity in Fujian Province from a dietary nutrition perspective

Resources and land carrying capacity are vital to the survival and development of human society and form the foundation for ensuring food security. However, evaluating land carrying capacity solely based on grain production is overly simplistic. A comprehensive assessment from the perspective of dietary nutrition is needed to more accurately reflect the actual carrying capacity of land. This study evaluates the land carrying capacity of Fujian Province from the perspectives of three major nutrients: calories, protein, and fat, using statistical data from 2007 to 2022. It employs models such as the nutrient supply model, land carrying capacity model, center of gravity model, and grey prediction model to evaluate the land carrying capacity situation in Fujian Province during 2007-2022 and to predict the trends in land carrying capacity from 2023 to 2032. The results indicate that, during the study period, the following were observed: (1) Total food production in Fujian Province significantly increased, primarily dominated by plant-based foods, though there has also been a proportional increase in animal-based foods, demonstrating distinct regional production characteristics. (2) The overall supply of food nutrients in Fujian Province rose, with the greatest increase observed in fat supply. The main sources of nutrients are grains, meat, and aquatic products. (3) The land carrying capacity of Fujian Province, viewed through different nutrient perspectives, has increased, with the southeastern region exhibiting a higher carrying capacity compared to the northwest. Over time, the spatial imbalance in land carrying capacity has decreased, with the centroid shifting from south to north. (4) The degree of nutrient restriction in Fujian Province has decreased, leading to an improvement in of land carrying capacity, with fewer constraints observed in inland cities. Xiamen and Quanzhou face triple nutrient restrictions, Fuzhou and other areas face dual restrictions, Zhangzhou faces single restrictions, while the remaining cities have sufficient nutrient availability. The comprehensive land carrying capacity index of Fujian Province has improved, transitioning from a "critical overload" to an "excess of balance" state. (5) From 2023 to 2032, both the land carrying capacity and the resident population of Fujian Province are predicted to increase. While the constraint on protein will weaken, constraints on fat and calories will remain significant. The land carrying capacity is expected to remain in a state of "critical overload", with the conflict between people and land continuing to be severe.