<b>China's interprovincial flows of </b><b>t</b><b>ourism-based</b><b> </b><b>cultural ecosystem services and its bundling effects across metacoupled systems</b>

In metacoupling anthropocene, the flow of cultural ecosystem services (FCES) can establish intangible connections between human and natural systems, even across vast distances. Nature-based cross-border tourism provides a means to measure FCES and their non-physical well-being patterns. However, studies on cross-boundary FCES are scarce according to the metacoupling framework (including intracoupling, pericoupling and telecoupling systems). Identifying the patterns, status, mechanisms, and spillover effects of interprovincial FCESs in China is essential for conserving nature-based cultural services, managing the flow, and achieving sustainable development of tourism. Here, we obtained the location of all 5A-rated natural attractions (receiving systems), along with their Internet Protocol (IP) Address (sending systems) with total sample size of 202,557, from ctrip.com, the largest online platform in China for sharing travel information and comments of tourist sites. Based on tourism flows, we investigated the pattern of interprovincial and bundling effects of FCES in 31 Chinese provinces (excluding Hong Kong, Macao and Taiwan), utilizing the metacoupling framework and social complex network modeling. We found that the decrease in FCES density is associated with a rise in the radial extent. The telecoupling of FCES (0.34) outperforms proximity pericoupling (0.20), but intracoupling (0.46) remains dominant.Northeastern provinces displaying atourist preference for telecoupling while Southwestern exhibit a significant intracoupling. Additionally, forest ecosystems provide approximately one-third of all cultural services, while oasis and cryosphere ecosystems exhibit the highest telecoupling performance. There are also noteworthy bundling effects (nine clusters in China) that are accompanied by the small-world property. We consider the implementation of regional tourism cooperation (bundling effects) and the enhancement of CFESmanagement as beneficial tactics for achieving the sustainable tourism under the metacoupled system.