How Space and Time Influence Regional Linkage: A Study on the Mechanism of Central Collapse in the Tourism Development of the Chengdu-Chongqing Economic Circle

The "central collapse" of tourism development reflects the uneven tourism development in dual-core or multi-core urban agglomerations. Understanding the spatiotemporal mechanisms behind its formation can help promote coordinated tourism development in urban agglomerations. The spatiotemporal distribution of tourism flows is a fundamental factor influencing tourism development in urban agglomerations. This study focuses on the Chengdu-Chongqing Economic Circle, constructing a multi-agent tourism flow micro-simulation model based on multi-source data. The model simulates tourist behavior under specific travel days, uses network node degree to analyze the distribution characteristics of tourism flow networks in the Chengdu-Chongqing region, and employs the rank-size rule to assess the impact of travel days on the spatial distribution balance of tourism flow. Finally, two indicators—scenic spot density and playtime density—are introduced to analyze the relationship between the distribution of tourism flows and the spatial distribution of scenic spots in Chengdu-Chongqing. The study finds that: (1) The tourism flow micro-simulation model developed in this paper can dynamically reflect spatiotemporal changes in tourism flow and analyze the spatiotemporal mechanisms behind "central collapse" in tourism development. This model can also serve as a virtual simulation platform for evaluating the applicability of regional tourism development decisions. (2) The increase in travel days promotes the expansion of the spatial distribution of tourism flow but also exacerbates the unevenness of regional tourism flow distribution. (3) There is a significant positive correlation between tourism flow distribution and scenic spot spatial distribution. Therefore, increasing the density of scenic spots in central Chengdu-Chongqing, particularly by enhancing the density of playtime, is key to retaining tourists.