## 3 Results
### Evaluation of the Results of Characterization of the Basic Quantity of Urban Green Spaces  
#### 3.2.1 Evaluation of the Basic Quantitative Characteristics of Urban Green Zones  
The assessment of the fundamental quantitative characteristics within the five-ring framework yielded a score of 0.84, corresponding to an evaluation grade of 1 (Figure 5a). This indicates that the overall configuration of urban green zone distribution within Beijing's Fifth Ring Road is exemplary. The area designated for urban green zones is adequate, and the fundamental quantitative characteristics of the city are deemed reasonable, thereby facilitating the effective use of the functional value associated with urban green zones. The green space of Beijing's Fifth Ring shows an increasing trend, and the distribution of green space in parks shows a pattern of \"more in the north and less in the south\". Vegetation mainly occurs in large patches, distributed in the western and northern areas of the Fourth to the Fifth Ring Road. The assessment of the fundamental quantitative characteristics of urban green spaces located within the Fourth to the Fifth Ring yielded the highest evaluation results, classified at grade I. The evaluation grades of the Second Ring, the Second to Third Ring, and the Third to Fourth Ring were grade II. The assessment outcomes followed the order Second Ring, Second to Third Ring, Third to Fourth Ring, and Fourth to Fifth Ring. Furthermore, it is recommended that the area encompassed by three rings be suitably expanded. The green zone coverage area of parks within the study area can reach more than 60% (Figure 6a). Based on the analysis results, the parks within the study area exhibit a substantial degree of green space coverage, regardless of their location in either the inner or outer ring road regions. Figure 5: Comprehensive evaluation of indicators of the study area in different ring belts: (**a**) basic quantitative characteristics of urban green zones; (**b**) green space landscape pattern; (**c**) green space diversity; (**d**) information on urban green spaces. Regions exhibiting elevated levels of tree cover are predominantly located within the third ring, specifically in the southern section of Dongcheng District and the western area of Chaoyang District (Figure 6b). In the 1 \(\times\) 1 km grid, the minimum value of green coverage of arborvitae within the fifth ring was 55.32%, the maximum value was 100%, the average value was 83.9%, and the percentage of grids with higher-than-average values was 56.43%. These findings indicate that irrigation holds a predominant role in the urban green spaces located within the confines of the study area, thereby influencing the overall green coverage metrics. Irrigation areas are primarily concentrated in the southeastern region of the Third Ring Road, which indicates homogeneity in vegetation types, characterized by a substantial prevalence of irrigation and a notable deficiency in grasslands. Furthermore, the coverage of irrigation in the northeastern, southeastern, and southwestern areas within the Fourth and Fifth Ring Road was comparatively low. Figure 6: Spatial distribution maps of basic quantitative characteristics of urban green zones in the district: (**a**) spatial distribution of green coverage; (**b**) spatial distribution of irrigation cover; (**c**) spatial distribution of blue–green space share. Areas with high amounts of blue-green spaces were mostly large park aggregation areas, and the largest range was distributed in the northwest of the fourth-fifth ring (Figure 6c). In the 1 \(\times\) 1 km grid, the minimum value of the blue-green space proportion in the fifth ring was 0.16%, the maximum value was 95.23%, and the average value was 29.16%. The percentage of grids with higher-than-average values was 40.39%. These findings indicate that the spatial distribution of blue-green spaces within the study area closely resembles that of green coverage, predominantly concentrated in the northern region of the city.