Assessing Land Resource Carrying Capacity in China's Main Grain-Producing Areas: Spatial-Temporal Evolution, Coupling Coordination, and Obstacle Factors

The land resources in the main grain-producing areas (MGPAs) provide a solid foundation for grain production, and promotion of the sustainable utilization of land resources in these areas is crucial for ensuring national food security. To comprehensively assess the land resource carrying capacity (LRCC) in China's MGPAs, we utilized the driver-pressure-state-impact-response (DPSIR) framework and applied the analytic hierarchy process (AHP) and entropy weight (EW) method to analyze the spatial-temporal evolution of LRCC in China's MGPAs from 2000 to 2020. By establishing a coupling coordination model, we explored the coupling coordination relationships among LRCC subsystems and identified key factors hindering the balanced development of LRCC using an obstacle degree model. The research results indicate that the LRCC in China's MGPAs generally shows an increasing trend with a continuously growing rate, with the LRCC in the southern regions surpassing that in the northern regions. The overall coupling coordination of LRCC demonstrates an increasing trend, although the growth rate is decreasing. The coupling coordination level of LRCC in the southern regions is generally higher than that in the northern regions, and the gap in coordination levels between various regions is narrowing. The state and pressure subsystems significantly influence the balanced development of LRCC. Indicators such as arable land area per capita, grain production yield per unit area of arable land, grain production yield per capita, forest land area per capita, and grassland area per capita play vital roles in the development of LRCC. Based on these findings, we have put forward targeted recommendations.