Table 1.

Community park characterization data acquisition

Feature Type	Variable		Variable Definition	Quantification Technique	References
Natural environmental features		Green rate of greenery (%)	The average ratio of the area occupied by plants in the image (GA) to the total area of the image (IA). The green view index for the community park research unit is represented by the average proportion of green pixels in the images from four directions.	Photographs were taken using a camera with a 24-mm focal length at a fixed height of 1.6 m above ground level, and semantic segmentation was performed using SemanticSegmentation_v1.0.	[41–44]
		Greening implantation rate (%)	The ratio of the vertical projection area of vegetation to the built-up land area within the community park.	Government websites, phone and email communications, park layout board information records, Bigemap, ArcGIS, and Office measurement tools.	[45–47]
		Green space shapes	The Landscape Shape Index (LSI) represents the shape of a green space. The specific formula for calculating the Landscape Shape Index is: where LSIi, denotes the shape index of green space patch i, P i is the perimeter of patch i, and Ai is the area of patch i.	The UNI-T land measurement instrument is used for calculating land area.	[48, 49]
Artificial facility features		Number of facilities for physical activity (count)	During the data collection phase, we focused on collecting the specific number of facilities in four types of areas: sports equipment zones, exercise pathway areas, activity square areas, and specialized sports areas.	On-the-spot investigation.	[8, 13, 50, 51]
		Number of rest facilities (count)	This includes the number of seating areas, as well as the number of artificial shading and shelter structures.	On-the-spot investigation.	[52–54]
		Number of surrounding substitute facilities (count)	This refers to fitness facilities located around the surveyed parks. Starting from the center of the older adults’ activity area within the community park, we used the Amap (Gaode Map) to search for nonmotorized public sports and recreational facilities within a 1 km radius. The data for surrounding alternative facilities near the community park samples were recorded.	Gaode map area search	[55, 56]
Site planning features		Transportation accessibility	Based on the digitized road network of Changchun City (https://www.openstreetmap.org), we conducted an accessibility assessment of open spaces. Using the entrances of each community park as starting points, 10-minute walking buffers for older adults were generated using the Mapbox isochrone API. Park accessibility was then compared by analyzing the area of these buffers.	ArcGIS network analysis technology, Mapbox API.	[57–60]
		Site scale (ha)	Data on the construction area and water area of the target parks were obtained through the website of the Changchun Forestry and Landscape Bureau (http://ccylj.changchun.gov.cn/zjyl/index_7.html), as well as through phone and email inquiries.	Government websites, phone and email data collection, and park layout board information recording.	[61–63]
		Spatial vitality	We selected the Baidu heatmaps for the period from September 10 to 16, 2023, including Mondays, Wednesdays, Fridays, and both Saturday and Sunday. From 06:00 to 22:00, we captured data every 2 h using a scale of 1:100,000, resulting in a total of 45 snapshots, which were used as the foundational data for regional vitality analysis.	ArcGIS georeferencing, ImageJ pixel statistics.	[64, 65]