Identifying Boundaries and Open Spaces of the Village Using Bidirectional Buffer Method

The study of boundaries helps to understand the relationship between human activities and the natural environment and guides sustainable planning and construction. However, the traditional method of identifying boundaries based on distance thresholds has limited accuracy, so this study aims to propose a more promising approach. The Bidirectional Buffer (BDB) method uses lines and arcs to distinguish solid and open space on the boundary and therefore has a better ability to describe local spatial characteristics. The Geographic Information System (GIS) was used to perform data computation, buffer analysis, and spatial visualization for the case study. By calculating and comparing indicators of Sinuosity, Concavity, and Openness, the new method was proved to be more accurate than the old method in the cross-scale analysis. In addition, the BDB method could identify the open spaces at the edges and inside of villages and distinguish them according to the boundary characteristics, and thus has good application prospects.