Abstract
Abstract
Urbanization is reorganizing land-use and functional relationships around cities, yet urban-rural classifications and built-up expansion reveal little about how agricultural, production and living functions are transformed. We tracked functional data across the fringes of 15 Chinese cities from 2012 to 2022 and conditionally extended transitions to 2035. The share of the low-dominance mixed state (MF), where functions coexist, increased from 46.3% to 66.5%, while the eco-agriculture-dominant state (EA) declined from 45.9% to 29.7%. Changes were dominated by bidirectional transitions between EA and MF and shifts from production-and-office dominance to MF. Under historical continuation, modeled 2035 shares were 67.9% for MF and 25.5% for EA, with six minority states retaining 6.6%. Compared with ecological protection, development stress produced the largest EA reductions in Beijing, Changsha and Chongqing, whereas mixed-function guidance produced the largest MF increases in Shenzhen, Ningbo, Guangzhou, Chengdu and Chongqing. Responses varied among cities, supporting governance differentiated by ecological sensitivity, MF change and historical trajectory. High-risk eco-agricultural areas require protection and flood retention; mixed-function transitions require coordinated public services; and developed areas require stock upgrading. These findings support China's "three zones and three lines" spatial planning, urban renewal and progress towards sustainable cities, climate adaptation and terrestrial ecosystem protection.