Spatio-temporal evaluation of ecological security of cultivated land in China based on DPSIR-entropy weight TOPSIS model and analysis of obstacle factors

Cultivated land's ecological security ensures human well-being and is critical to global food security. However, the unchecked expansion and excessive exploitation of agricultural resources have led to considerable land degradation issues in China, including soil erosion, contamination, and environmental degradation, raising concerns over the cultivated land ecological security (CLES). Current research on cultivated land (CLES is relatively limited, particularly at the national level across different provinces. In addition, a unified and comprehensive CLES evaluation index system has yet to be formed. To fill this research gap, we construct a CLES evaluation system with 35 indicators from three dimensions of "society-natural-economy" based on the DPSIR model framework and entropy weight TOPSIS model. Simultaneously, we conducted a spatial-temporal analysis of CLES in 31 provinces of China from 2012 to 2021 and applied the obstacle degree model to analyze the main factors impeding the CLES in China. The results showed that: (1) During the study period, the CLES and its subsystems showed a good development trend. Spatially, the CLES in China presents a regional difference of "high in the east and low in the west" and a significant regional difference among provinces. (2) The spatial CLES in different provinces of China presents a significant positive correlation, and the spatial clustering effect of CLES is gradually strengthening. The "High-High" clusters are mainly distributed in the northeast and eastern regions, while the "Low-Low" clusters are mainly located in the western region. (3) From the perspective of the criterion level, the state subsystem and the impact subsystem are the main obstacles hindering the improvement of CLES in China. At the indicator level, the common obstacle factors affecting the enhancement of CLES across provinces in China include soil erosion control intensity, number of green food certifications, per capita agricultural loans, per capita cultivated land area, and per capita grain production. Our research results can provide practical policy reference for further improving the ecological protection of cultivated land.