A new framework for dynamic visual landscape quality evaluation of greenways based on perceived sensory dimensions: A case study of Chengdu urban greenway

Greenways serve as important carriers for leisure and recreational activities in urban areas, and the visual landscape quality is a crucial consideration in greenway construction. Scientific and reasonable evaluation of visual landscape quality is significant for planning, construction, and management of greenway systems. This study focuses on the greenways in the Chengdu Urban Ecological Zone. Utilizing image segmentation technology, we constructed an image-based evaluation index system, and innovatively introduced color harmonization and visual entropy to better evaluate dynamic visual landscapes. Based on the Perceived Sensory Dimensions framework, this system is designed to assess the dynamic visual landscape quality, incorporating the dimensions of harmonization, richness, and distinctiveness. The following research findings are obtained: 1) The greenway landscape is complex and diverse. Creating an evaluation system for dynamic visual quality helps assess the landscapes' natural and cultural aspects in a multidimensional, quantitative, and objective way; 2) There are spatial variations in the visual landscape quality of the greenways in the Chengdu Urban Ecological Zone. By dividing the greenways into evaluation units with characteristic parks as nodes, it is found that high-value sections of visual landscape quality are distributed in the southeast part, while low-value sections are distributed in the southwest, and #17 has the highest visual landscape quality at 0.62; 3) The different land cover types on either side of the greenway show a coordinating or inhibiting effect on visual landscape quality. Ecological lands showed a coordinating effect on visual landscape quality, agricultural lands showed a suppressing effect on visual landscape quality, and construction lands showed a coordinating effect on characteristics. The proposed method for analyzing visual landscape quality can support the planning, construction, and management of regional greenway systems.