Is greenery green? An analytical comparison between the planned, visual, and perceived green

Abstract

This research established a comprehensive evaluation system for urban ecological assessment. Through research in the fields of urban planning, urban design, and cognitive psychology, this paper defines three ecological evaluation indexes correspondingly. They measure the vegetation coverage of land (planning green), the visibility of vegetation from the pedestrian’s viewpoint (visual green), and the psychological perception of greenery by human (perceived green). This study uses computerized parametric analysis, computerized deep learning, data visualization, and statistical methods to achieve an accurate description of the three evaluation indicators. This study assumes that the three green values may behave consistently or inconsistently at each point. Therefore, this study, on the one hand, tries to analyze the potential factors affecting each green indicator. On the other hand, by analysing the consistency or discrepancy of the three green values, this research revealed the potential link between urban spatial type and integrated ecological properties. Four areas of Brisbane dominated by different functions were selected for this study (Red Hill and Bardon for residential areas, Brisbane City for downtown CBD, and Woolloongabba for industrial areas). The results of the study demonstrate the credibility and applicability of the three green indicators in different areas, examine the various factors affecting ecology, and provide new design strategies and ideas for urban designers.