How to resolve the conflicts of urban functional space in planning: A perspective of urban moderate boundary

The multi-functionality and the finiteness of land resources collectively determine the inevitable space conflicts among urban construction space (SUC), grain production space (SGP), and ecological protection space (SEP) in planning. Moreover, the increasing urban expansion is expected to further exacerbate these conflicts. However, there is a lack of research on solving space conflicts in planning under the multi-objective. Given this, taking Xuzhou City as an example, using planning data, we analyzed the patterns of space conflicts. Then we proposed a novel method to extract the urban moderate boundary (UMB) based on the principle of value equilibrium. Finally, using UMB as the space boundary to solve the conflicts. The results show that we detected three types of space conflicts, namely construction-production conflicts (CPC), construction-ecological conflicts (CEC), and production-ecological conflicts (PEC), with an area of 17.31 km2, 14.13 km2, and 3.24 km2 of each conflicting area respectively. The land value corresponding to the UMB is 941.90 yuan / km2. The CPC and CEC within the UMB should be reserved as SUC, those outer parts of the boundary should be reserved as SGP and SEP. The PEC should be reserved as SEP according to the principle of ecological priority. After conflict resolution, the new layout of urban functional space was obtained, showing an area of 240.18 km2, 42.56 km2, and 55.35 km2 for SUC, SGP, and SEP, respectively. The new perspective and method proposed in this paper can provide a reference for urban planning and urban functional space layout optimization.