Structural equation model of the spatial distribution of water engineering facilities along the Beijing-Hangzhou grand canal and its relationship with natural factors

Water engineering facilities are a crucial component of the Beijing-Hangzhou Grand Canal during the Ming and Qing dynasties, and their distribution is closely related to the hydrological and topographical characteristics of the area. In this study, we reconstructed the canal network distribution map and water engineering facilities database of the Ming and Qing periods using ArcGIS (Geographical information systems software) 10.8 software. We employed Amos (Analyze of Moment Structures) 26.0 software to investigate the influence of various natural environmental factors on the selection of water engineering facility sites. The results revealed a significant correlation between the spatial distribution of water engineering facilities and the main channel slope and slope direction, which had a direct impact. The estimated coefficient for the main channel slope was -0.166, showing a negative correlation with the spatial distribution of water engineering facilities, while the estimated coefficient for the main channel slope direction was − 0.112, also indicating a negative correlation. Moreover, the estimated coefficient for the watershed area where water engineering facilities were located was -0.096, demonstrating a negative correlation. In contrast, the effects of tributary slope and slope direction on the spatial distribution of water engineering facilities were indirect, mediated by the watershed area where these facilities were situated. The effect size for tributary slope was -0.017, showing a negative correlation, while the effect size for tributary slope direction was 0.010, indicating a positive correlation with the spatial distribution of water engineering facilities.The study achieves the integration of the heritage of water engineering facilities along the canal from point to line, provides data support for the construction of the cultural heritage corridor of the canal, and facilitates the promotion of heritage protection and rational layout, which is of great significance to the understanding of the canal culture.