Impact of rural labor transfer on the sustainable intensification of cultivated land use

Over-intensification of cultivated land can often result in intensification traps for food production. Ever increasingly outstanding negative effects can also threaten the national food security and agricultural economy. The sustainable intensification of cultivated land use (SICLU) can be expected to balance the economic and ecological benefits of agricultural production. However, it is unclear whether the rural labor transfer on SICLU in the context of the rapid development of new urban and rural revitalization. In this study, the super-efficiency Slacks-Based Measure (SBM) model was utilized to evaluate the SICLU level in the 30 provincial-level administrative regions in China from 1990 to 2020. The theoretical connotation of SICLU was combined to further clarify the impact of rural labor transfer on SICLU using a threshold model. The results showed: 1) The SICLU level shared a general trend of first decreasing and then increasing from 1990 to 2020. Specifically, the mean value of SICLU showed a fluctuating downward trend, which decreased from 0.448 in 1990 to 0.393 in 2002, with an average annual decline rate of -1.735%. The mean value of SICLU showed a fluctuating upward trend after 2002. Its average value increased from 0.448 in 2002 to 0.551 in 2020, with an average annual growth rate of 8.627%. The SICLU level was ranked in the descending order of the Northeast > West > East > Central regions. There was a large difference among regions. 2) The empirical analysis with the panel threshold model showed that there was a significant trend of a U-shaped curve for the influence of rural labor transfer on SICLU. Once the rural labor transfer was lower than the threshold value (0.351), there was an inhibitory effect on the development of SICLU. By contrast, the rural labor transfer promoted the development of SICLU, when the rural labor transfer was higher than the threshold value (0.351). Meanwhile, robustness testing was carried out to adjust the core explanatory variables, sample data, and measurement model. 3) The heterogeneity analysis showed that there was an unbalanced impact of rural labor transfer on the SICLU, due to the difference of regional agricultural economy and natural endowment. In agriculturally developed areas and plain areas, the rural labor transfer was easy to achieve the factor transfer and efficiency improvement, which greatly contributed to the high SICLU level. However, there was no significant in the less developed agriculture and mountainous areas. Consequently, the non-agricultural transfer of rural redundant labor force should be reasonably modified to realize the sustainable intensive transformation of cultivated land use. The land transfer market and intermediary service organization should be optimized to realize the large-scale management of agricultural production; Financial subsidies and credit services can also be provided for the main body of direct management of cultivated land, in order to alleviate the financial constraints. Much attention should be paid to the cultivation of a new quality agricultural labor force to optimize the allocation structure of agricultural factors. Moreover, the regional economy and natural endowment should also be considered to explore the sustainable-intensive path of cultivated land use suitable for regional conditions.