Investigating the Influence of Land Ecological Environment Quality on Sustainable Development Goals: A Case Study of 31 Provinces in China

Land resources constitute the fundamental basis for human survival and a core element of social development. The quantity, quality, and ecological condition of land resources are crucial for human well-being and sustainable development, and they make significant contributions to achieving the United Nations Sustainable Development Goals (SDGs). However, the influence of land ecological quality on the implementation of the SDGs has not yet been fully clarified. This study utilizes 1 km spatial resolution geospatial data and statistical data to construct a land ecological environment quality evaluation index system based on the Pressure–State–Response (PSR) model, analyzing the spatiotemporal dynamics of land ecological environment quality in China from 2010 to 2020 (with five-year intervals). In addition, the Spearman correlation coefficient was employed to examine the relationships between the land ecological environment quality index (LEEQI), pressure index (PI), state index (SI), response index (RI), and the implementation of SDGs 6, 11, 12, and 15, and to further explore how geographical economic zones influence the effects of these indices on the achievement of the SDGs. The results indicate that land ecological quality in China shows a strong north–south gradient, while the east–west differentiation is relatively weak, and the overall trend is increasing. The LEEQI values ranged from 0.16 to 0.48; the PI values ranged from 0.00 to 0.24; the SI values ranged from 0.03 to 0.29; and the RI values ranged from 0.01 to 0.26. The LEEQI gap between the western and northeastern regions narrowed significantly, from 0.10 to 0.07. LEEQI and RI promote the achievement of all four SDGs, whereas PI and SI mainly promote the realization of SDGs 6, 11, and 12. The synergistic effects of the four indices on the SDGs are observed in the central, eastern, and western regions, with the most significant effects occurring in western China. Specifically, LEEQI shows the strongest correlation with SDG 6; both PI and SI exhibit synergistic effects with SDGs 12 and 15; and RI demonstrates synergistic effects with all four SDGs. These findings suggest that improving land ecological quality is crucial for advancing the achievement of the SDGs. Furthermore, given that land ecological environment quality and its dimensions exert different influences on the implementation of the SDGs across geographical economic regions, it is necessary to develop tailored and region-specific strategies, particularly in western China, where maximizing improvements in land ecological quality is crucial for promoting sustainable development.