城市绿色空间对改善居民福祉和城市可持续发展具有重要的意义。城市绿色空间指的是城市中以自然或人工植被为主要形态的开放空间，为居民提供了多种生态系统服务。根据其权属，城市绿色空间可分为公共绿色空间，如公园，和私人绿色空间，如独栋住宅的庭院。而在人口密集的城市中，相比独栋住宅，更为常见的住宅类型是居住小区，居住小区内住宅楼栋外的开放空间统称为小区绿地，其使用者主要为小区居民，是一种半公共绿色空间。对于小区居民而言，小区绿地是居民最方便到达的户外绿色空间。而居民在室内也能接触到由自然要素构成的绿色空间，如家中的植物和窗外自然景观。从城市中的公园、到住宅室外的小区绿地、再到住宅室内的植物和窗外自然景观，这些不同空间尺度下的绿色空间与居民日常生活息息相关。研究表明，这些绿色空间能够通过减少环境危害、恢复身心健康、促进身体活动和增强社会凝聚力四种途径对居民福祉产生贡献。
已有研究证实，城市公园有助于改善健康水平、提升生活满意度等，而公园的距离、面积和质量是影响其福祉效益的主要因素，许多研究以此构建公园可达性指标评估城市绿地公平性。在已有研究的基础上，为全面理解不同城市绿色空间对居民福祉的贡献，本研究定量化评估小区绿地和住宅室内绿色空间对居民主观福祉的贡献及影响因素，并综合考量小区绿地和公园在绿地公平性方面的作用。而新冠疫情期间居民外出受限，对户外绿色空间的访问骤减。在此背景下，分析住宅室内绿色空间、小区绿地、公园之间的联系，探讨三者在外出受限情景下的共同作用。研究结果有助于深入认识不同尺度绿色空间对居民福祉的贡献及它们之间的联系，这对于科学绿化城市空间、提升城市可持续性具有重要的意义。
本研究的主要内容包括以下几方面：（1）基于对北京市五环内78个样本小区的实地调查，量化小区绿地特征，分析小区绿地访问对居民生活满意度的贡献，以及影响居民访问绿地的主要特征。（2）根据以上研究结果，通过网络数据提取北京市五环内所有小区的绿地特征，定量化评估小区绿地质量等级，计算小区绿地质量指数，从街道尺度分析小区绿地质量指数与公园可达性的空间分布和在不同社会群体中的分布，并评估综合考虑小区绿地和公园后对绿地公平性的影响。（3）基于对全国范围内城市居民的线上问卷调查，量化家中植物和窗外自然景观，分析其对居民生活满意度的贡献。（4）基于线上问卷中新冠疫情前与疫情期间的调查，分析日常情况下居民家中植物和窗外自然景观、小区绿地访问、和公园访问之间的联系，并比较它们的联系在疫情期间外出受限情景下的变化。
本研究的主要结论如下：
（1）北京市五环内78个小区的绿地特征调查数据和6783份有效访谈问卷的分析结果表明，居民经常访问小区绿地，而且这有助于提升生活满意度。85%的受访者每周至少访问一次小区绿地，他们的生活满意度在8分及以上的可能性（1分为非常不满意，10分为非常满意）是其他受访者的1.3-1.5倍。在考虑居民社会经济特征的前提下，分析小区绿地的面积、植被、设施和管理维护等特征对居民访问小区绿地的影响，结果表明小区绿地中有可开展多种活动的小广场、凉亭/长廊等遮荫设施、以及将车辆与小区绿地中活动区域分开（“人车分离”）能够显著增加居民每周访问小区绿地的可能性，分别为75%、42%、100%，未发现其他特征对小区绿地访问的显著影响。
（2）基于以上结果评估北京市五环内3000个小区内的绿地质量，结果显示其沿环路梯度呈现“里低外高”的空间分布格局。综合考虑小区绿地和公园可达性，使得绿地可达性的空间异质性增强，绿地可达性与优势群体（人均收入、本科学历人口比例、本地户籍人口比例）和高需求群体（老年人和未成年人比例）的负相关性增强（相关系数的绝对值由0.2-0.4提高至0.3-0.5），优势群体的绿地可达性变得更低，高需求群体的绿地可达性也进一步降低。
（3）全国城市居民线上问卷调查有效数据（4500份）分析显示，住宅室内绿色空间在提升居民生活满意度方面发挥了积极作用，而且家中植物比窗外自然景观的提升作用更明显。对于窗外有很多或完全是自然景观的受访者，他们生活满意度为10分的可能性是窗外有一些自然景观的受访者的1.4倍。对于家中有很多植物的受访者，他们的生活满意度为10分的可能性是家中没有植物的受访者的2.5倍。
（4）疫情期间外出受限情景下，受访者对公园和小区绿地的访问均大幅减少，小区绿地的下降幅度（50%）略少于公园（60%）。对比日常和疫情期间外出受限情景下住宅室内绿色空间与小区绿地和公园访问的联系，结果表明在外出受限情景下，住宅窗外自然景观和家中植物的增加伴随着经常访问小区绿地和公园的可能性的降低。窗外没有自然景观和有一些自然景观的受访者中，经常访问两种绿地的比例从44%显著降低至15%（p < 0.05）。类似地，家中没有植物和有很多植物的受访者中，经常访问两种绿地的比例从40%显著降低至18%（p < 0.05）。这表明在特定时期中，家中植物和窗外的自然景观可能在一定程度上补充了居民对外出访问绿地的需求，但在日常情景中家中植物并未发现类似的关联（p > 0.05）。
综上，城市公园、小区绿地和住宅室内绿色空间均对居民生活满意度有显著的提升作用。与此同时，三者在一定程度上相互补充，在绿色空间公平性方面以及应对外出受限情景时共同发挥作用，为长期稳定地改善居民福祉做出贡献。未来小区绿地设计改造中应优先保障活动广场、遮荫设施和人车分离，并统筹规划建设公园和小区绿地，同时重视室内植物和窗外绿色视域，加强城市建筑空间绿化，促进城市可持续发展。

Urban green space is of great significance for improving residents' well-being and sustainable urban development. Urban green space refers to open space in the city, mainly formed by natural or artificial vegetation. Urban green space provides various ecosystem services to residents. According to the ownership, green spaces can be divided into public green spaces, such as parks, and private green spaces, such as courtyards in single family homes. In densely populated cities, the more common type of housing compared to single family homes is residential quarter. The open space outside residential buildings in the quarter (collectively referred to as residential quarter green space, RQGS) is a kind of semi-public green space, which is mainly used by residents living in the residential quarter. RQGS is the most accessible outdoor green space for residents. In addition, residents can interact with green space in their home, such as household plants and green view outside the windows (indoor green space). From parks in the city, to RQGS in residential areas, and to indoor green spaces, these green spaces at different spatial scales are closely related to residents' daily lives. Studies have shown that these green spaces can contribute to residents’ well-being by reducing environmental harms, restoring attention and stress, promoting physical activity, and enhancing social cohesion.
Previous studies have confirmed that urban parks can help improve health levels and life satisfaction, while the distance, area, and quality of parks are the main factors affecting their benefits. Moreover, studies have explored the equity of green spaces by constructing park accessibility indicators. In order to comprehensively understand the contribution of different urban green spaces to residents' well-being, this study quantitatively evaluates the contribution and factors of RQGS and indoor green space to residents' well-being, and comprehensively considers the role of RQGS and parks in the equity of green space. During the COVID-19 pandemic, residents were restricted in going out, and their visits to outdoor green spaces decreased sharply. In this context, this study analyzes the connection between indoor green spaces, residential green spaces, and parks in residential areas, and explores their common roles on residents’ well-being in the restricted outdoor situation. The research results will help deeply understand the contribution of green spaces at different scales to residents’ well-being and their connections, which is of great significance for scientifically greening urban space and enhancing urban sustainability.
The main content of this study includes the following four parts: (1) Based on a field survey in 78 sampled residential quarters in the area within the fifth ring road in Beijing, this study quantified the RQGS characteristics, analyzed the contribution of RQGS visits to residents' life satisfaction, and the main factors of residents' visits to RQGS. (2) Based on the results of above content, this study used website data to extract features of all RQGS in the area within the fifth ring road in Beijing, and then quantified the quality of RGQS. Based on this, the study analyzed the linkage of RQGS and park accessibility, and its impact on the equity of green space accessibility at the neighborhood scale. (3) Based on a nationwide online questionnaire survey for urban residents, the study quantified the household plants and the green view outside the window, and analyzed their contributions to residents' life satisfaction. (4) Based on the online questionnaire survey, analyzing the relationships among indoor green space in residential area, visits to RQGS, and visits to park, and comparing their changes under restricted outdoor situations.
The main conclusions of this study are as follows:
(1) By analyzing the field survey data of 78 residential quarters within the fifth ring road in Beijing (6783 responses), the study found that residents often visit to RQGS, which is helpful to life satisfaction. 85% of the respondents visited RQGS at least once a week, and they were nearly 1.3 to 1.5 times more likely to rank life satisfaction at 8 and above (1 is very dissatisfied, 10 is very satisfied) than others. Taking into account the impact of RQGS characteristics such as the area, vegetation, facilities, and maintenance management on residents' visits, the study found having an open space for multiple activities, a pavilion, or shaded trail, and separating ground traffic and parking from green space will greatly increase likelihood to use RQGS at least once a week, which is 75%, 42%, 100%, respectively. There were no significant impact of other characteristics on RQGS visits.
(2) Based on the above results evaluating the RQGS quality of 3000 residential quarters within fifth ring road in Beijing, it showed a spatial distribution pattern of "low inside and high outside" along the gradient of the ring road. After comprehensively considering the accessibility of RQGS and park at neighborhood scale, it sharpened the disparities between the city center and city periphery. In addition, the absolute values of negative correlation coefficient between the green space accessibility and residents’ socio-economic conditions were increased from 0.2-0.4 to 0.3-0.5. It indicated that the green space accessibility of advantaged groups decreased, and that of high-demand groups also further decreased.
(3) The analysis of effective data from a nationwide online questionnaire survey of urban residents (4500 responses) showed that indoor green space in residential area have played a positive role in improving residents' life satisfaction, and the improvement effect of household plants is more significant than that of green window view. Respondents with greener window view were 1.4 times more likely to rank life satisfaction at 10, compared with respondents having a window view with “average green”. Respondents having many household plants were 2.5 times more likely to rank life satisfaction at 10 than those with no household plant.
(4) The study found many respondents stopped frequent visit to greenspace during the pandemic, among which parks lost more frequent visitors (60%) than RQGS (50%). Moreover, presence of green window view or household plants were related to less likelihood of frequent visits to RQGS and park during the pandemic. 44% respondents with “none green” window view frequently visit greenspace and the proportion has significantly reduced to 15% for respondents with “average green” window view (p < 0.05). In terms of household plants, 40% respondents with none household plants visited greenspace frequently, and the proportion was 18% for those with many household plants respectively (p < 0.05). This indicated that green window view and household plants may to some extent complement the residents' demand of greenspace visit during a specific period, while no significant association of household plants was detected before the pandemic (p > 0.05).
In summary, urban park, green space in residential quarter, and indoor green space each has a significant effect on residents' life satisfaction. At the same time, they can to some extent complement each other, play a common role in the equity of green space and in responding to restricted outdoor situations, and together contribute to residents' well-being. To promote sustainable urban development, future practice should give open space, shading facilities, and vehicles management priority in RQGS design and renovation. Parks and green space in residential quarters should be planned and deployed overall. Indoor plants and green view outside the windows should be paid to more attention, and it can be increased by greening urban architectural spaces.