The Fairness Evaluation on Achieving Sustainable Development Goals (SDGs) of Ecological Footprint: A Case Study of Guanzhong Plain Urban Agglomeration

The sustainable development of the Guanzhong Plain Urban Agglomeration (GPUA), which is a pivotal Belt and Road hub, is critical for achieving the UN’s 17 SDGs. Based on the ecological footprint (EF) model, this study innovatively constructs a three-dimensional framework integrating natural and human-made capital, using the Gini coefficient and spatiotemporal analysis to evaluate resource allocation fairness in the GPUA from 2005 to 2022. Key findings include the following: (1) EF and GDP grew continuously at annual rates of 11.43% and 11.87%, while ecological carrying capacity (EC) stabilized, pushing the GPUA toward its ecological threshold under the Environmental Kuznets Curve (EKC). Moreover, the increasing Ecological Pressure Index (EPI) shows that after 2014, the GPUA has trended toward “extremely unsafe” status. (2) The ecological carrying capacity Gini coefficient (G 1 , 0.1710–0.6060) fluctuated significantly, while the economic contribution Gini coefficient (G 2 , 0.1039–0.3519) showed a narrow upward trend; since 2015, the comprehensive Gini (G < 0.4) indicates that the EF aligns with its EC and economic contribution. (3) The GPUA shows fair resource allocation. Tongchuan, Baoji, and Xianyang are low economic contribution and high ecological contribution; Xi’an and Yangling Demonstration Zone are high economic contribution and low ecological contribution; Weinan is low ecological contribution and low economic contribution. These findings provide critical insights for hub urban agglomerations to achieve the 17 SDGs through fair ecological resource allocation and sustainable development.