With the increasing demand of urbanization for land, Chinese cities and towns are gradually growing from plains to mountainous areas. Serving as an important ecological base and natural components of urban spatial structure, mountains partly determine a city's overall landscape layout and appearance, especially to mountainous cities. The spatial structure of "mountain–city integration" refers to planning and building urban pattern by taking mountains as structural elements at the city scale, and embodies as an urbanized spread towards the mountains at the neighborhood scale. Urban streets support citizens' daily commuting, leisure and recreation, cultural exchange, and environmental protection. The landscape of pedestrian spaces greatly affect pedestrians' visual aesthetic perception, which is defined by people's visual interaction and feedback with the landscape. In the context of promoting mountain–city integration, research on LVAQ (landscape visual aesthetic quality) assessment of urban mountains in a relatively further visual range is expected.
The study, conducted by An Qi, Xiao Huabin, Guo Yanxin, and Wu Junying, from Harbin Institute of Technology and Harbin Institute of Technology, focuses on the historic downtown of Jinan, a typical mountainous city, analyzes the landscape aesthetic visual characteristics of street pedestrian spaces. It measures the spaces' landscape visual aesthetic quality by using panoramic images; evaluates the visibility of high-visual-aesthetic-quality urban mountainous landscape to urban streets. The work entitled "Landscape Visual Aesthetics Measurement, Assessment, and Improvement of Street Pedestrian Spaces in Mountainous Cities—Case Study on the Historic Downtown of Jinan, Shandong Province " was published on the journal of Landscape Architecture Frontiers (September 14, 2022).
The historic downtown of Jinan, Shandong Province was selected as the study area, which covers an area of about 203.51 km2 and more than 1,300 streets. The study area sits in the region of the Taishan Mountains and accommodates a number of mountain parks and urban scenic areas. The study area, typically mountain–integrated, faces the challenge of how to organically improve the quality of urban slow-lifestyle spaces including street pedestrian spaces.
This study uses massive streetscape data and deep learning methods, combined with an overlay analysis on the visibility of high-visual-aesthetic-quality urban mountainous landscape (HVAQUML), to conduct overall LVAQ evaluation of urban street pedestrian spaces of multiple characteristics based on a large sample size and in an efficient method, in order to provide a reference for improving urban landscapes of mountain-integrated cities. There are mainly four stages: data collection and processing of streetscape images; LVAQ assessment of urban streets pedestrian spaces; evaluation of the visibility of HVAQUML to the streets in the study area; and overall evaluation and optimization of LVAQ of street pedestrian spaces in the study area.
The study found that based on the spatial structure of mountain–city integration in the study area, urban street pedestrian spaces with high LVAQ can not only provide citizens with visual pleasure and slow-lifestyle spaces, but also serve as corridors among mountains and other natural landscape elements in the city, so as to improve the city image by highlighting the aesthetic quality of urban mountains, especially the mountains with high-aesthetic-quality landscapes. Urban street spaces with varied levels and scales were different in terms of their friendliness to walking activities, and the specific elements that affect their visual aesthetics of the landscape also differ. Therefore, for the strategies of optimizing landscape visual aesthetic experience of urban street pedestrian spaces, streets' environmental elements related to characteristics of naturalness, diversity, harmony, openness, and disturbance should be adjusted in line with their level and scale, as well as their cultural, historical, and environmental qualities.
