The impact of urbanization on cultivated land "trinity" protection and its policy implications

Urban development and construction is a major driver of cultivated land loss. Based on the panel data of 277 prefecture-level cities from 2000 to 2022, this paper employs spatio-temporal analysis to reveal the evolving relationship between urbanization and the "trinity" protection of cultivated land. Furthermore, it utilizes a two-way fixed effect model to empirically analyze the total and sub-effects of urbanization on this protection framework. It also explores the differences in the impact effects from the perspective of land, population and economic urbanization. The results show that: (1) During the study period, the urbanization level of all cities increased annually. Spatially, the distribution exhibited a distinct pattern characterized by higher levels in the east than in the west, continuous development along the coast versus isolated growth points for inland areas, and higher concentrations in provincial capitals compared to other cities. The level of cultivated land "trinity" protection shows an inverted N-shaped fluctuation over time, while its spatial pattern evolved from an initial unipolar pattern structure to a north-south dual-core configuration. The cold spots of the two clusters always coincide highly in the western region, while their hot spot clusters exhibit a dynamic seesaw relationship in space. (2) Urbanization exerts a significant overall negative impact on the "trinity" protection of cultivated land. Specifically, it leads to a reduction in both the quantity and quality of cultivated land. (3) Land urbanization leads to a decline in the level of cultivated land "trinity" protection, while, in contrast, population urbanization enhances it. (4) The heterogeneity analysis reveals that the negative impact of urbanization on the "trinity" protection of cultivated land is significantly stronger in major grain-producing areas and in cities with more favorable natural conditions for farming. Within the context of high-quality development, our findings offer theoretical and empirical support for advancing new urbanization and strengthening comprehensive cultivated land protection.