Correlation Between Winter and Summer Visible Green Index and Green Vision Factors in Residential Areas

Residential area landscape affects the physical and mental health of residents, and the visible green index (VGI) is of great significance to evaluate the health function of the landscape and guide its renovation and planning. This research selects a total of 607 viewpoints from 23 communities in Hangzhou City to capture the panoramic VGI. For the first time, the research uses the seasonal concept of winter, summer and annual difference in VGI, and incorporates the comparison of differences in green vision factors between groups to explore the impact mechanism of VGI. The result shows that: 1) High-rise residential buildings often have a higher level of VGI. The difference in housing prices affected by greening investment can measure the level of VGI in residential areas. 2) The VGI of recreational viewpoints is the highest, but the VGI of roads can better represent the VGI level in residential areas, and the scenes with hard landscape as the core should underline the quality and individual characteristics of greening investment than the green quantity. 3) The annual difference of VGI in Hangzhou reaches 15%. The complete vegetation structure can increase the residential area VGI level and seasonal changes. In the landscape planning and design of the residential areas, it is necessary to avoid fragmentation of the green space, and ten years should be used as the unit of VGI evaluation. The research largely explains the influence mechanism of winter and summer VGI and green vision factors, which has guiding significance for the planning, application and evaluation of green quantity of residential area landscape.