## 4 Discussion  
### Reasons for Changes in Green Visibility Equity  
Our study reveals that population density and green visibility have both increased in Wuhan's central urban areas, largely due to the effective implementation of urban policies. Since the introduction of the _Wuhan New Urbanization Plan (2014-2020)_, the city has made significant progress in urbanization, including improvements in core urban services and the integration of urban and rural development. Between 2014 and 2021, Wuhan's urbanization rate increased from 55.67% to 84.56%, reaching the average level of developed nations. During this period, a series of greening policies were enacted, which contributed to the increase in GVI. For instance, the city enhanced urban street greenery by planting trees along roads, forming continuous and dense tree-lined avenues. By the end of 2021, Wuhan had developed 2116 km of greenways and established over 350 pocket parks, bringing the total number of parks to more than 700. The _202 Wuhan Greening Work Plan_[57] aims to increase this number to 1000 by the end of the 14 th Five-Year Plan period. Despite these achievements, our study indicates that green visibility equity has not significantly improved. This could be because traditional green space planning in China often relies on metrics like the green coverage rate and per capita green space, which emphasize increasing the total amount of green space and its equal distribution. However, these metrics may overlook the unequal distribution of green space, especially in densely populated areas where green space supply is limited [2]. Additionally, previous research has demonstrated that there is no significant correlation between GVI and indicators measuring the quantity of urban green space development [58]. Simply increasing green spaces along roads may not effectively address the inequality in green  
Figure 10: Spatial distribution (**a**) and change values (**b**) of location quotient change rates for constant residential units from 2014 to 2021.  
visibility; instead, priority should be given to low-income communities with insufficient green space supply [59]. Furthermore, limited public involvement in planning often leaves lower-income residents with little influence over green space quantity and location, leading to distribution imbalances. As many low-income residents lack time to participate in public meetings due to work and family responsibilities, relying solely on public participation is ineffective. Proactive government policies are necessary to mandate additional greenery in low-income neighborhoods, ensuring equitable access to green space benefits. Our study has focused on the spatial equity of green visibility and draws conclusions that align with previous research. Surrounding environmental characteristics influence the distribution of GVI through two pathways, including the nature of land use and the physical attributes of streets [60]. High-visibility residential areas are often located along rivers and lakes, consistent with findings from a case study in Guangzhou [35]. Existing water systems, such as the Yangtze River, Han River, East Lake, and South Lake, provide a solid ecological foundation for Wuhan's greenway construction. Numerous riverside and wetland parks have added rich green resources to the city. Conversely, low-visibility residential areas are typically concentrated around major urban roads (including expressways), aligning with [PERSON]'s findings [36]. Although sections of Wuhan's second ring road have improved green visibility by adding central green belts, the wide road width still limits canopy coverage, increasing the visible proportion of sky and road surfaces in street view images. Reducing road widths in lower-income neighborhoods could create space for tree canopies, mitigating heat islands and enhancing green visibility. Furthermore, the widespread use of elevated expressways restricts the planting of mature trees, further diminishing green visibility and exacerbating heat island effects [33].