Assessment, Evolutionary Trends, and Convergence of Land Green Utilization Efficiency in Three Northeastern Provinces of China Undergoing Population Shrinkage

To achieve the green and efficient utilization of land in China’s three northeastern provinces and to harmonize the human–land relationship, this paper examines the spatiotemporal evolution and convergence of land green utilization efficiency (LGUE) in these provinces against the backdrop of population contraction. Utilizing data from 2000 to 2020, we employ the geometric mean method to characterize the features of population contraction and construct a global reference non-desired super-efficiency SBM-DEA model to measure LGUE. The dynamic evolution of LGUE is analyzed using kernel density estimation and spatial visualization techniques, and its convergence is tested through σ-convergence and absolute β-convergence methods. The results indicate that during the study period, the population in the three northeastern provinces has experienced overall contraction, predominantly characterized by a “growth-to-contraction” pattern, which is more pronounced in resource-based cities. Land green utilization efficiency exhibits a fluctuating upward trend, evolving spatially into a distribution pattern of “high in the middle and low on both sides along the northeast–southwest axis”. The degree of dispersion among cities also shows an upward fluctuation, with evidence of σ-convergence and absolute β-convergence. Regional balance has improved. This study concludes that there is significant potential for enhancing land green utilization efficiency in the three northeastern provinces. We recommend adopting the “smart contraction” model to promote coordinated development between population and land, capital and land, as well as ecology and land, thereby fostering sustainable development in these regions.