Residents’ Living Environments, Self-Rated Health Status and Perceptions of Urban Green Space Benefits

Abstract

Urban green space (UGS) could contribute to sustainable urban development. Studying residents’ perception of UGS ecological benefits could provide the empirical basis to improve UGS management and quality of life. Based on the questionnaire surveys of 432 residents in Beijing, assisted by non-parametric statistical tests, this paper assessed the relationships between residents’ living environments and self-rated health status and their impacts on residents’ perceptions of UGS ecological benefits. We paid attention to residents’ perceptions of UGS’s notable thermal environmental benefits under the climate-change backdrop. The results showed that: (1) Residents were inclined to perceive direct UGS ecological benefits better than the indirect types; (2) Residents growing up in the city had better self-rated health status than those growing up in the suburb and the village; and residents growing up in the suburb had a better understanding of the cooling benefits of green walls; (3) Residents currently dwelling in the city had a better understanding of UGS benefits, including shading, cooling by green roofs, mitigating the heat island effect and enhancing urban biodiversity, than those dwelling in the village; and (4) Residents with “very good” self-rated health status had a significantly better understanding of UGS benefits regarding shading, providing varied colors and habitats, storing carbon, purifying air, and collecting rainwater.

1. Introduction

Urban green space (UGS) refers to the natural, semi-natural or artificial land covered by vegetated surfaces in the city, which can be formal and informal. They include urban parks, gardens, various outdoor recreational venues with vegetation, street greening, and remnant natural or ruderal vegetated enclaves embedded in the urban matrix [1]. As essential components of the urban environment, UGS contribute notably to human wellbeing [2]. They bring substantial positive impacts on the residents’ physical and mental health, spanning from pregnancy outcomes [3] to disease risk [4], mortality [5], and longevity [6]. Concerning mental health, they reduce the risk of depression [7], anxiety and psychological distress [8,9].

Of the multiple UGS ecological benefits, the thermal benefits tend to be emphasized. They ameliorate the urban thermal environment and improve the urban microclimate by shielding direct solar radiation, absorbing heat by evapotranspiration and directing air movement to usher welcomed cooling effects [10,11]. Lowering the ambient temperature can mitigate the urban heat island effect and thermal impacts [12,13]. Climate change would superpose its warming to accentuate the thermal stress. The cooling functions of even small UGS can make a difference [14] by depressing the thermal harms on residents’ health. The health damages associated with urban warming include increased risk of death from respiratory diseases [15], myocardial infarction due to short-term heat stress [16], and adverse pregnancy outcomes, including stillbirth due to extreme temperatures [17].

UGS also bring various thermal and ecological benefits to residents through plant functions, including two categories [15]. First is the items that could be directly perceived by residents, such as air purification [18], noise reduction [19], anti-glare effect [20], pleasant and masking scent [21] and colorful landscape [22]. Second is the items that could not be directly perceived, such as carbon storage [23], stormwater regulation [24], and biodiversity conservation [25]. These benefits could be subsumed under the Common International Classification for Ecosystem Services (CICES V5.1), namely regulating, provisioning, and supporting services (

Table 1. Detailed classification of UGS thermal and ecological benefits adopted in the questionnaire survey.

B1: Thermal Benefits	B2: Ecological Benefits
Regulating service: Cooling B1-1 Offer evapotranspiration to cool urban air temperature B1-2 Provide cool shading in hot sunny weather B1-3 Reduce wear of air conditioners B1-4 Reduce heat sickness caused by heatwaves and heatstroke B1-5 Green roof can lower the surface temperature of the building and keep the interior cooler B1-6 Green wall can lower the surface temperature of the building and keep the interior cooler B1-7 Ameliorate urban heat island effect B1-8 Create cool island effect B1-9 The cool island effect of parks can extend to adjacent areas B1-10 Help adapt to climate change	Provisioning service: Environment-landscape: B2-1 Absorb carbon dioxide and mitigate the greenhouse effect
	B2-2 Remove air pollutants to improve air quality
	B2-3 Abate noise intrusion into indoor space
	B2-4 Reduce road glare and increase road safety B2-5 Provide natural fragrant smell
	B2-6 Offer natural seasonal changes Regulating service: Water
	B2-7 Absorb and retain rainwater B2-8 Reduce the release of rainwater into the drainage system B2-9 Reduce investments in stormwater drainage infrastructure B2-10 Reduce the likelihood of urban flooding B2-11 Recharge groundwater B2-12 Reduce soil erosion
	Supporting service: Biodiversity B2-13 Allow more wildlife to dwell and forage in cities B2-14 Protect endangered species from predators B2-15 Raise urban biodiversity

) [26].

UGS constitute the most accessible and perceptible natural endowment for urban residents. Since the late 19th century, urban planners and designers have furnished cities with UGS to alleviate the adverse consequences of urbanization and industrialization and meet people’s psychological need to contact nature [27,28]. Studying residents’ perception of UGS benefits can deepen understanding of the benefits per se, evaluate the intricate relationships between UGS and human wellbeing [2], and predict residents’ demands, attitudes, preferences, and behaviors vis-a-vis UGS [29]. It can also elicit the amenities and disamenities of UGS directly from the users’ perspective. Such research findings could optimize strategies to fully realize UGS benefits, improve residents’ enjoyment and happiness, and strengthen UGS management to fulfill these objectives [22].

Recent studies have examined residents’ perceptions of UGS benefits. For example, Grahn and Stigsdotter (2010) analyzed Swedish residents’ overall perception of UGS and identified eight perception dimensions [30]. They generally preferred a serene ambience, followed by space, nature, species richness, refuge, culture, prospect and social interaction. Casado-Arzuaga et al. (2013) evaluated 500 residents’ perceptions of the Bilbao Metropolitan Greenbelt (peri-urban ecosystems) ecosystem services [31]. They found that cultural services were perceived most commonly, followed by regulating services.

Mullaney et al. (2015) observed that most residents could perceive the main benefits of streetside green spaces, including shading, noise reduction and landscape improvement [32]. Rupprecht et al. (2015) investigated residents’ perceptions of informal UGS in Brisbane (Queensland, Australia) and Sapporo (Hokkaido, Japan) [33]. They found that residents were inclined to perceive biodiversity conservation, air filtration, beautification, and opportunities for children to play and expose to nature experience. Tian et al. (2020) found that residents in Wuhan had the strongest perceptions of climate regulation benefits of UGS, followed by cultural services, air pollution abatement, stormwater regulation and biodiversity conservation [34]. Under the climate change backdrop, the UGS thermal benefits are critical to residents’ health and quality of life. This particular perception reflects residents’ awareness and response to climate change, but there is a lack of in-depth investigation.

There is a tendency for urban residents to omit or be oblivious of some less direct or less tangible supporting and provisioning ecosystem services of UGS. People tend to have a limited understanding of biodiversity of UGS, and neglect the contributions of informal green areas [35]. Park users often have limited knowledge of plants, especially the spontaneous ones, and focus their attention on the cultivated ornamental species [36]. On the other hand, the cultural ecosystem services such as regulating and recreational functions that can offer direct and more tangible benefits are better appreciated or recognized [37].

Various intrinsic factors, including individual traits (such as gender, age, education level, family status, and personal self-rated health status) and extrinsic factors (such as UGS design and management and venue environs), could influence perceptions of UGS benefits. Most studies explored the impacts of socioeconomic characteristics on perceptions. For example, Abass et al. (2019) indicated that residents’ perceptions of the UGS environmental and health benefits were primarily affected by their education level [38]. Koo et al. (2013) conducted face-to-face interviews with 823 urban residents in South Korea [39]. They found that gender and age had insignificant effects on the perceptions of urban forest recreational services. Rupprecht et al. (2015) pointed out that the socioeconomic characteristics of the population (gender, age, income, and education level) had limited impacts on the perception of UGS benefits [33]. Instead, geography and culture were gauged as potential factors. Of these factors, the living environment is essential because it could play a key role in improving the quality of life. Romagosa (2018) found that in Barcelona, residents living near parks had a stronger perception of the park’s benefits of increasing physical health [40]. Shackleton et al. (2013) concluded that residents living in the suburb for high-income groups perceived aesthetic benefits of UGS more than those living in the countryside or the suburb built after racial segregation [41]. Tian et al. (2020) also indicated that of the three provincial capitals Wuhan, Changsha and Nanchang in China, residents in Wuhan had a stronger perception of climate regulation provided by UGS and residents in Changsha had a weaker perception of UGS’s benefit of supplying habitats [34]. However, few studies investigated the impact of the living environment at the critical and formative stages of life (such as childhood) on the perception of UGS benefits. The effects of childhood exposure tend to persist. For example, the lower socioeconomic conditions and unfortunate experiences in childhood would degrade physical and mental health in adulthood [42]. These imprints may result in different perceptions of UGS benefits.

Self-rated health status offers a subjective and comprehensive evaluation of one’s health according to one’s preferred definition. It galvanizes the current state of health in the physical, mental and social dimensions and embodies the expectations of future health conditions. It differs from objective measurements and reveals indirectly the individual’s evaluation of the quality of life [43,44]. Self-rated health status is affected by multiple factors, such as individual features [45], social relationships [46], and environmental conditions. The green space presents a potential mechanism for shaping self-rated health, which is amenable to perceiving UGS benefits to bring a higher self-rated health status [47,48]. The factors influencing health have differential impacts and imprints at different stages of a person’s life. It is still unclear whether residents’ living environment would influence their self-rated health status, especially in the critical childhood period.

Self-rated health status had been verified to affect the perception of UGS in parks. For example, in Barcelona, visitors with higher confidence in health have a stronger perception of the park’s benefits of improving health [40]. They also had a stronger perception of venue quality in some mountain parks in Fuzhou, China [49]. In the Kansas City metropolitan area, those with higher body mass index (BMI) perceived the park’s benefits of enhancing neighborhood communication than others [50]. However, few studies explored how residents’ self-rated health status would affect their perception of the UGS ecological benefits, especially the thermal ones.

Some research questions remain to be resolved: whether the childhood residential environment, a critical and sensitive period, impacts the self-rated health status in adulthood and whether the self-rated health status affects the perception of the UGS benefits of promoting health. We identified three focused study factors: childhood and adulthood living environments, self-rated health status, and perceptions of UGS ecological benefits. We hypothesized that the childhood and adulthood living environments could influence self-rated health status. These two background factors could shape the perceptions of a broad spectrum of UGS thermal and other ecological benefits. Detailed data on the triple factors were gleaned from a comprehensive questionnaire survey of Beijing residents. This study aimed to clarify the divergence and convergence in perceptions of UGS ecological benefits, especially thermal benefits, among residents exposed to dissimilar living environments and different self-rated health status. It is expected to provide some theoretical and practical hints to optimize UGS design and management to improve residents’ wellbeing and enjoyment and promote sustainable UGS development in Beijing and other cities.

2. Materials and Methods

Beijing is the national capital and the political, economic, transportation and cultural center of China. Located at 39°54′ N, 116°25′ E, it has 16,807.8 km² and 16 county-level administrative divisions. Beijing has a typical subhumid continental monsoon climate in the warm temperate zone, with hot and rainy summer, cold and dry winter, and short spring and autumn seasons. Affected by global warming and rapid urbanization, the annual average temperature in Beijing increased by 1.36 °C from 1961 to 2010, with the most significant warming in the southeast and central urban areas [51].

Beijing’s greenspace system is dominated by urban parks. The Beijing Master Plan (2004–2020) established the goal of building a ring of urban parks around the central city. By 2016, 61 parks had been built to constitute the germinal configuration of the urban park ring [52], which will be further augmented in due course. In 2018, the city’s main built-up area (located within the Fifth Ring-Road) covered approximately 660 km², with a total green space of 19,569.13 ha, and an average green patch size of 16.20 ha [53]. Beijing’s parks provide citizens and tourists with valuable leisure and recreation opportunities, and shoulder an important function of refuge sites to citizens in emergencies. During the pandemic outbreaks, the essential benefits of the parks’ open ecological spaces played a key role in regulating people’s psychological state and maintaining a healthy lifestyle.

Questionnaire surveys were conducted in 2018. Each questionnaire contained 32 questions and was divided into two parts. The first part probed the respondents’ perception (understanding and agreement) of UGS ecological benefits, divided into 10 specific thermal environmental benefits and 15 other ecological benefits (Table 1). The stated responses were measured using five-point Likert scales (from “1” don’t know/don’t agree to “5” know excellently/very strongly agree). The second part gleaned the key socio-demographic characteristics, childhood and current living environment, and self-rated health status of the respondents (

Table 2. Socio-demographic characteristics of the respondents compared with the residents in Beijing, China.

Respondents’ Characteristics	N	%	Residents’ Characteristics a	N (104)	%
Gender			Gender
Male	219	50.7	Male	1095.6	50.9
Female	213	49.3	Female	1058.6	49.1
Age			Age
20 & below	4	0.9	0–19	55.9	12.8
21–30	124	28.7	20–29	389.0	18.1
31–50	226	52.3	30–49	795.6	36.8
51–70	76	17.6	50–69	538.4	25.0
70 & above	2	0.5	70 & above	157.4	7.3
Marriage			Marriage
Single	102	23.6	Single	448.1	20.8
Married	315	72.9	Married	1583.8	73.5
Other	15	3.5	Other	122.4	5.7
Education			Education
Primary or below	8	1.9	Primary or below	248.8	11.6
Secondary	67	15.5	Secondary	1051.0	48.8
University	243	56.3	University	739.3	34.3
Postgraduate	114	26.4	Postgraduate	115.1	5.3
Childhood living environment
City	149	34.5
Suburb	64	14.8
Village	219	50.7
Current living environment
City	352	81.5
Suburb	40	9.3
Village	40	9.3
Self-rated health status
Excellent	105	24.3
Good	204	47.2
Fair	118	27.3
Bad	5	1.2
Very bad	0	0.0

^a Data on residents’ characteristics were collected from the Beijing Statistical Yearbook 2019 and the China Statistical Yearbook 2019.

). A stratified purposeful sampling scheme was established to obtain our representative sample of Beijing residents. The potential respondents were divided into six categories based on monthly household income (2017), namely <6000 Yuan, 6000–14,000 Yuan, 14,000–24,000 Yuan, >24,000 Yuan, Unemployed, and Retired. Data on the percentage of residents in each income category in Beijing were obtained from Baidu Wenku (2018). In each income category, representative occupations were identified, and the numbers of target respondents in each occupation were estimated. The work units with such potential respondents were identified and chosen randomly based on the respondent distribution plan. The questionnaires were then distributed to these units, such as hospitals, offices, factories, parks, etc. A total of 500 completed questionnaires were collected from the work units, of which 432 valid ones were enlisted for our analysis (Table 2).

Descriptive and inferential statistical analyses were applied using IBM SPSS 20.0 software. Descriptive statistics portrayed sample characteristics and respondents’ perceptions (understanding and agreement) on UGS ecological benefits. Since the data did not meet the standard of normal distribution and homogenization of variance, only non-parametric tests (Mann-Whitney test and Kruskal-Wallis test) were employed. We evaluated the impact of the living environments on residents’ self-rated health status and the impact of both attributes on the perceptions of UGS ecological benefit. A statistically significant difference was set at p < 0.05. The mean scores of understanding and agreement levels were calculated by multiplying the percentage of the respondents to the total with the corresponding scale value (1–5).

3. Results

3.1. Respondents’ Socio-Demographic Profile

Table 2 indicates that the overall characteristics of respondents were comparable to Beijing residents. About 219 (50.7%) respondents were male, similar to the 50.9% male residents in the population census. The 21–50 age group took up 81% of the respondents, and the 31–50 group was about twice as large as the 21–30 group. These proportions were similar to the census data. Few respondents were over 51 years, mainly due to their relatively low education level, poor visual acuity and inability to complete the questionnaire independently. Married respondents accounted for 72.9% of the respondents, followed by single (23.6%) and other marital status (3.5%), which were roughly equivalent to the official statistics. Most respondents (82.7%) received university and postgraduate education, followed by secondary (15.5%) and primary and below (1.9%). During childhood, over half of the respondents lived in the village (219, 50.7%), followed by city (149, 34.5%) and suburb (64, 14.8%). Most respondents currently lived in the city (352, 81.5%), with few in the suburb (40, 9.3%). Regarding self-rated health status, the highest group was “good” (204, 47.8%), followed by “fair” (118, 27.3%), “excellent” (105, 24.3) and “bad” (5, 1.2%).

3.2. Childhood and Current Living Environments versus Self-Rated Health Status

Table 3. The impacts of childhood and current living environments on self-rated health status ^a.

Living Environment		U	p
Childhood living environment Chi-square = 13.205, p = 0.001 **	City × Suburb	4320.500	0.240
	City × Village	12,982.000	0.000 **
	Suburb × Village	6185.500	0.122
Current living environment Chi-square = 1.852, p = 0.396	City × Suburb	6824.000	0.731
	City × Village	6196.000	0.181
	Suburb × Village	724.500	0.431

Note: The Kruskal-Wallis test was applied first. If the results showed significant differences, the Mann-Whitney test was then used for intra-group comparison, and the items with a significant level less than 0.05 were listed. ** means p < 0.01, boldface indicates a higher average term.

shows the impacts of childhood and current living environments on self-rated health status. Due to non-normal distribution, the data were analyzed by the non-parametric Mann-Whitney and Kruskal-Wallis tests. A significant difference in self-rated health status was found between respondents who lived in different environments in childhood. During childhood, the self-rated health status of respondents who lived in the city was significantly better than those who lived in the village. However, for the current living environment, no significant difference in self-rated health status was detected among the respondents.

3.3. Understanding and Agreement Levels of UGS Ecological Benefits

Table 4. Understanding and agreement levels of respondents on UGS ecological benefits.

	Understanding level a (%)							Agreement level b (%)
Benefit	5	4	3	2	1	Mean	Rank c	5	4	3	2	1	Mean	Rank c
B1: Thermal benefits
B1-1	15.51	37.50	31.25	12.96	2.78	3.50	6	27.78	42.36	20.83	7.87	1.16	3.88	9
B1-2	27.31	50.46	17.36	4.40	0.46	4.00	1	42.82	44.44	10.65	1.85	0.23	4.28	1
B1-3	18.29	38.19	28.47	13.66	1.39	3.58	4	30.32	41.44	22.45	4.63	1.16	3.95	7
B1-4	13.19	40.74	33.33	11.11	1.62	3.53	5	31.48	41.67	20.83	5.09	0.93	3.98	4
B1-5	17.13	44.44	26.85	10.42	1.16	3.66	2	34.95	40.28	18.29	5.56	0.93	4.03	2
B1-6	15.05	43.75	28.01	11.81	1.39	3.59	3	31.25	43.75	19.91	4.40	0.69	4.00	3
B1-7	14.12	30.09	32.64	19.44	3.70	3.31	9	30.79	35.65	28.24	4.63	0.69	3.91	8
B1-8	14.35	34.95	29.63	17.82	3.24	3.39	8	31.25	41.20	22.22	4.40	0.93	3.97	5
B1-9	8.80	27.31	35.42	23.84	4.63	3.12	11	23.84	37.27	30.56	7.18	1.16	3.75	11
B1-10	10.88	31.25	37.73	17.13	3.01	3.30	10	24.77	40.05	27.31	7.41	0.46	3.81	10
Mean	15.46	37.87	30.07	14.26	2.34	3.50	7	30.93	40.81	22.13	5.30	0.83	3.96	6
B2: Other ecological benefits
B2-1	26.85	40.74	22.92	9.03	0.46	3.84	3	39.81	40.97	16.20	2.55	0.46	4.17	3
B2-2	26.62	44.68	24.07	4.40	0.23	3.93	1	46.30	37.27	13.43	2.78	0.23	4.27	1
B2-3	21.76	42.36	25.23	9.95	0.69	3.75	4	41.16	39.30	14.88	4.42	0.23	4.17	4
B2-4	17.36	35.88	32.18	12.50	2.08	3.54	11	32.64	38.19	23.84	4.40	0.93	3.97	7
B2-5	22.22	36.11	31.48	8.56	1.62	3.69	5	33.33	38.43	21.06	6.25	0.93	3.97	8
B2-6	27.31	40.28	26.16	5.32	0.93	3.88	2	42.23	40.60	13.92	2.55	0.70	4.21	2
B2-7	18.06	39.58	31.25	9.26	1.85	3.63	6	30.56	44.44	19.91	3.94	1.16	3.99	6
B2-8	13.89	32.87	33.10	18.29	1.85	3.39	14	22.92	38.19	28.47	8.80	1.62	3.72	13
B2-9	9.95	25.00	39.58	23.15	2.31	3.17	16	19.91	34.72	33.33	10.88	1.16	3.61	15
B2-10	12.73	35.19	34.26	16.44	1.39	3.41	12	27.08	39.35	24.77	7.64	1.16	3.84	12
B2-11	18.29	38.19	29.17	12.96	1.39	3.59	9	31.94	40.28	20.14	6.94	0.69	3.96	9
B2-12	17.36	38.66	31.25	11.34	1.39	3.59	8	30.79	44.91	18.52	5.32	0.46	4.00	5
B2-13	14.35	31.94	30.32	17.82	5.56	3.32	15	23.15	34.03	20.83	16.20	5.79	3.53	16
B2-14	12.99	34.80	34.57	14.15	3.48	3.40	13	26.74	35.81	22.09	12.79	2.56	3.71	14
B2-15	18.10	38.98	29.23	11.60	2.09	3.59	7	31.55	38.52	22.27	5.34	2.32	3.92	11
Mean	18.52	37.02	30.32	12.32	1.82	3.58	10	32.01	39.00	20.91	6.72	1.36	3.94	10

^a Denotes understanding level: 5 for excellent; 4 good; 3 fair; 2 limited; 1 don’t know. ^b Denotes agreement level: 5 for very strong; 4 strong; 3 moderate; 2 weak; 1 don’t agree. ^c Ranked by the mean scores of individual benefit items within the B1 and B2 groups, respectively. The items in bold typeface mean they have higher mean values of understanding or agreement levels of respondents than others.

shows respondents’ perceptions of UGS thermal benefits and other ecological benefits reckoned by understanding and agreement levels. Concerning the understanding levels of thermal benefits, respondents expressing the “good” level contributed the largest proportion (37.87%), followed by “fair” (30.07%). The “don’t know” response was the smallest (2.34%). The mean scores of B1-1 to B1-6 were higher than the overall B1 mean score (3.50), with the highest and lowest mean scores being B1-2 (4.00) and B1-9 (3.12), respectively.

Regarding the agreement levels of UGS thermal benefits, respondents opining “strong” took the largest proportion (40.81%), followed by “very strong” (30.93%). The “don’t agree” reply was tiny (0.83%). B1-2, B1-4 to B1-6, and B1-8 captured exceptionally higher mean scores (circa 4.00 and above) than the B1 mean score (3.96), with the highest and lowest values being B1-2 (4.28) and B1-9 (3.75), respectively. Overall, the mean scores of agreement levels were notably higher than the understanding levels.

For the understanding levels of other ecological benefits, the “good” response accounted for the largest proportion (37.02%), followed by “fair” (30.32%). The “don’t know” reply was the smallest (1.82%). The mean scores of B2-1 to B2-3, B2-5 to B2-7, B2-11, B2-12, and B2-15 were higher than the overall B2 mean score (3.58), with the highest and lowest being B2-2 (3.93) and B2-9 (3.17), respectively.

Concerning the agreement levels of other ecological benefits, the “strong” answer occupied the largest proportion (39.00%), followed by “very strong” (32.01%). The “don’t agree” reaction had the smallest proportion (1.36%). B2-1 to B2-7, B2-11, and B2-12 had higher mean scores than the B2 mean score (3.94), with the highest and lowest being B2-2 (4.27) and B2-13 (3.53), respectively.

Comparing the mean scores of thermal and other ecological benefits could tell their differential perceptions by respondents. For understanding levels, the mean score of B1 thermal benefits at 3.50 was lower than B2 other ecological benefits at 3.58. For agreement levels, the mean score of B1 thermal benefits at 3.96 was only slightly higher than B2 other ecological benefits at 3.94.

3.4. Childhood and Current Living Environments Shaping Perceptions of UGS Ecological Benefits

Table 5. Impacts of the childhood living environments on respondents’ perceptions of UGS ecological benefits ^a.

Benefit		Understanding Level	Agreement Level
B1: Thermal benefits
	B1-1	Chi-square = 0.491, p = 0.782	Chi-square = 2.876, p = 0.237
	B1-2	Chi-square = 0.271, p = 0.873	Chi-square = 0.806, p = 0.668
	B1-3	Chi-square = 11.317, p = 0.003 ** C1 × C3-(U = 13458.500, p = 0.003 **) C2 × C3-(U = 5699.000, p = 0.018 *)	Chi-square = 2.225, p = 0.329
	B1-4	Chi-square = 0.040, p = 0.980	Chi-square = 0.106, p = 0.948
	B1-5	Chi-square = 3.898, p = 0.142	Chi-square = 2.741, p = 0.254
	B1-6	Chi-square = 6.183, p = 0.045 * C1 × C2-(U = 3830.000, p = 0.016 *)	Chi-square = 1.502, p = 0.472
	B1-7	Chi-square = 0.765, p = 0.682	Chi-square = 1.582, p = 0.453
	B1-8	Chi-square = 1.346, p = 0.510	Chi-square = 0.136, p = 0.934
	B1-9	Chi-square = 1.787, p = 0.409	Chi-square = 2.923, p = 0.232
	B1-10	Chi-square = 0.176, p = 0.916	Chi-square = 1.083, p = 0.582
B2: Other ecological benefits
	B2-1	Chi-square = 1.277, p = 0.528	Chi-square = 3.275, p = 0.195
	B2-2	Chi-square = 2.778, p = 0.249	Chi-square = 1.095, p = 0.578
	B2-3	Chi-square = 0.660, p = 0719	Chi-square = 0.253, p = 0.881
	B2-4	Chi-square = 2.381, p = 0.304	Chi-square = 2.413, p = 0.299
	B2-5	Chi-square = 0.141, p = 0.932	Chi-square = 1.235, p = 0.539
	B2-6	Chi-square = 2.594, p = 0.273	Chi-square = 0.100, p = 0.951
	B2-7	Chi-square = 4.351, p = 0.114	Chi-square = 5.532, p = 0.063
	B2-8	Chi-square = 0.747, p = 0.688	Chi-square = 1.290, p = 0.525
	B2-9	Chi-square = 1.430, p = 0. 489	Chi-square = 2.352, p = 0.309
	B2-10	Chi-square = 0.477, p = 0.788	Chi-square = 1.646, p = 0.439
	B2-11	Chi-square = 0.186, p = 0.911	Chi-square = 1.862, p = 0.394
	B2-12	Chi-square = 1.056, p = 0.590	Chi-square = 1.882, p = 0.390
	B2-13	Chi-square = 0.844, p = 0.656	Chi-square = 1.147, p = 0.564
	B2-14	Chi-square = 1.171, p = 0.557	Chi-square = 4.793, p = 0.091
	B2-15	Chi-square = 0.893, p = 0.640	Chi-square = 2.349, p = 0.309

Note: The Kruskal-Wallis test was applied first. If the results showed significant differences, the Mann-Whitney test was then used for intra-group comparison; the items with significant level < 0.05 were listed. C1, C2 and C3 represent the understanding level of respondents who lived during childhood in city, suburb, and village, respectively; c1, c2 and c3 represent the agreement level of respondents who lived during childhood in the city, the suburb, and the village, respectively. For example, C1 × C3-(U = 13458.500, p = 0.003 **) indicates significant differences in the understanding level of UGS ecological benefits between respondents who lived during childhood in city and village, respectively, and the respondents who lived during their childhood in the city had better understanding level than those who lived in the village. ^a * means p < 0.05, ** means p < 0.01. Bold font denotes statistical significant difference.

shows the influence of childhood living environments on perceptions of UGS benefits. Respondents who lived in the city and the suburb had a significantly higher understanding level of B1-3 than those living in the village. Furthermore, respondents who lived in the suburb had a significantly higher understanding level of B1-6 than those living in the city. Insignificant differences were observed in other understanding and agreement levels of UGS benefits among respondents who dwelt in different environments during childhood.

Table 6. Impacts of current living environments on respondents’ perceptions of UGS ecological benefits ^a.

Benefit		Understanding Level	Agreement Level
B1: Thermal benefits
	B1-1	Chi-square = 1.011, p = 0.603	Chi-square = 1.794, p = 0.408
	B1-2	Chi-square = 7.785, p = 0.020 * N1 × N3-(U = 5398.000, p = 0.009 **)	Chi-square = 11.609, p = 0.003 ** n1 × n2-(U = 5761.000, p = 0.041 *) n1 × n3-(U = 5209.500, p = 0.003 **)
	B1-3	Chi-square = 0.967, p = 0.617	Chi-square = 5.415, p = 0.067
	B1-4	Chi-square = 1.009, p = 0.604	Chi-square = 3.646, p = 0.162
	B1-5	Chi-square = 4.318, p = 0.115	Chi-square = 9.629, p = 0.008 ** n1 × n3-(U = 5051.500, p = 0.002 **)
	B1-6	Chi-square = 0.652, p = 0.722	Chi-square = 4.163, p = 0.125
	B1-7	Chi-square = 0.585, p = 0.747	Chi-square = 6.334, p = 0.042 * n1 × n3-(U = 5408.000, p = 0.012 *)
	B1-8	Chi-square = 0.139, p = 0.933	Chi-square = 7.209, p = 0.027 * n1 × n2-(U = 5524.500, p = 0.019 *)
	B1-9	Chi-square = 1.540, p = 0.463	Chi-square = 2.714, p = 0.257
	B1-10	Chi-square = 4.383, p = 0.112	Chi-square = 5.464, p = 0.065
B2: Ecological benefits
	B2-1	Chi-square = 0.637, p = 0.727	Chi-square = 3.521, p = 0.172
	B2-2	Chi-square = 0.202, p = 0.904	Chi-square = 3.437, p = 0.179
	B2-3	Chi-square = 2.423, p = 0.298	Chi-square = 4.259, p = 0.119
	B2-4	Chi-square = 2.464, p = 0.292	Chi-square = 5.892, p = 0.053
	B2-5	Chi-square = 0.033, p = 0.984	Chi-square = 2.596, p = 0.273
	B2-6	Chi-square = 0.084, p = 0.959	Chi-square = 5.751, p = 0.056
	B2-7	Chi-square = 3.762, p = 0.152	Chi-square = 4.464, p = 0.107
	B2-8	Chi-square = 0.011, p = 0.994	Chi-square = 3.871, p = 0.144
	B2-9	Chi-square = 1.911, p = 0. 385	Chi-square = 0.456, p = 0.796
	B2-10	Chi-square = 1.141, p = 0.932	Chi-square = 1.813, p = 0.404
	B2-11	Chi-square = 0.061, p = 0.970	Chi-square = 0.165, p = 0.921
	B2-12	Chi-square = 2.537, p = 0.281	Chi-square = 0.225, p = 0.894
	B2-13	Chi-square = 1.469, p = 0.480	Chi-square = 2.531, p = 0.282
	B2-14	Chi-square = 0.533, p = 0.766	Chi-square = 2.708, p = 0.258
	B2-15	Chi-square = 4.368, p = 0.113	Chi-square = 7.265, p = 0.026 * n1 × n3-(U = 5308.500, p = 0.008 **)

Note: N1, N2 and N3 represent the understanding level of respondents who currently lived in the city, the suburb, and the village, respectively; n1, n2 and n3 represent the agreement level of respondents who currently lived in the city, the suburb, and the village, respectively. ^a * means p < 0.05, ** means p < 0.01. Bold font denotes statistically significant difference.

indicates the influence of current (adulthood) living environments on perceptions of UGS benefits. Respondents living in the city had a significantly higher understanding level of B1-2 than those living in the village. Respondents living in the city had a significantly higher agreement level of B1-2 than those living in the suburb and the village. Respondents living in the city had significantly higher agreement levels of B1-5, B1-7 and B2-15 than those living in the village. Respondents living in the city had a significantly higher agreement level of B1-8 than those living in the suburb.

3.5. Self-Rated Health Status Shaping Perceptions of UGS Ecological Benefits

Table 7. Impact of self-rated health status on respondents’ perceptions of UGS ecological benefits ^a.

Benefit		Understanding Level	Agreement Level
B1: Thermal benefits
	B1-1	Chi-square = 3.290, p = 0.349	Chi-square = 4.832, p = 0.185
	B1-2	Chi-square = 8.192, p = 0.042 * H1 × H3-(U = 5057.500, p = 0.010 *)	Chi-square = 3.421, p = 0.331
	B1-3	Chi-square = 0.128, p = 0.988	Chi-square = 0.618, p = 0.892
	B1-4	Chi-square = 4.706, p = 0.195	Chi-square = 5.287, p = 0.152
	B1-5	Chi-square = 0.271, p = 0.965	Chi-square = 0.911, p = 0.823
	B1-6	Chi-square = 0.742, p = 0.863	Chi-square = 0.226, p = 0.973
	B1-7	Chi-square = 1.538, p = 0.674	Chi-square = 2.103, p = 0.551
	B1-8	Chi-square = 2.583, p = 0.461	Chi-square = 3.871, p = 0.276
	B1-9	Chi-square = 2.344, p = 0.504	Chi-square = 0.885, p = 0.829
	B1-10	Chi-square = 4.143, p = 0.246	Chi-square = 5.260, p = 0.154
B2: Other ecological benefits
	B2-1	Chi-square = 9.213, p = 0.027 * H1 × H2-(U = 8806.000, p = 0.007 **) H1 × H3-(U = 4964.500, p = 0.007 **)	Chi-square = 6.060, p = 0.109
	B2-2	Chi-square = 18.164, p = 0.000** H1 × H2-(U = 8464.000, p = 0.001**) H1 × H3-(U = 4366.000, p = 0.000**)	Chi-square = 9.775, p = 0.021 * h1 × h2-(U = 9113.000, p = 0.019 *) h1 × h3-(U = 4847.500, p = 0.002 **)
	B2-3	Chi-square = 1.663, p = 0.645	Chi-square = 3.486, p = 0.323
	B2-4	Chi-square = 1.370, p = 0.713	Chi-square = 1.019, p = 0.797
	B2-5	Chi-square = 2.597, p = 0.458	Chi-square = 4.121, p = 0.249
	B2-6	Chi-square = 8.999, p = 0.029 * H1 × H2-(U = 9135.500, p = 0.025 *) H1 × H3-(U = 4879.500, p = 0.004 **)	Chi-square = 5.585, p = 0.134
	B2-7	Chi-square = 7.911, p = 0.048 * H1 × H3-(U = 5040.000, p = 0.011 *)	Chi-square = 4.674, p = 0.197
	B2-8	Chi-square = 3.979, p = 0.264	Chi-square = 3.638, p = 0.303
	B2-9	Chi-square = 2.548, p = 0. 467	Chi-square = 2.215, p = 0.529
	B2-10	Chi-square = 5.777, p = 0.123	Chi-square = 1.790, p = 0.617
	B2-11	Chi-square = 5.338, p = 0.149	Chi-square = 1.874, p = 0.599
	B2-12	Chi-square = 3.117, p = 0.374	Chi-square = 0.991, p = 0.803
	B2-13	Chi-square = 14.135, p = 0.003 ** H1 × H3-(U = 4673.000, p = 0.001 **) H2 × H3-(U = 9548.500, p = 0.001 **)	Chi-square = 5.117, p = 0.163
	B2-14	Chi-square = 0.778, p = 0.855	Chi-square = 4.308, p = 0.230
	B2-15	Chi-square = 5.617, p = 0.132	Chi-square = 4.298, p = 0.231

Note: H1, H2 and H3 represent the understanding level of respondents with excellent, good and fair self-rated health status, respectively; h1, h2 and h3 represent the agreement level of respondents with excellent, good, and fair self-rated health status, respectively. ^a * means p < 0.05, ** means p < 0.01. Bold font denotes statistically significant difference.

shows the impacts of respondents’ self-rated health status on perceptions of UGS ecological benefits. For thermal benefits, respondents expressing “very good” self-rated health status had a significantly higher understanding level of B1-2 than those with a “fair” status. However, for agreement levels of UGS thermal benefits, the self-rated health status did not bring significant differences for all benefit items.

For other ecological benefits, respondents self-rated health status had a significant influence on one-third of the understanding levels (Table 7). Respondents with “very good” self-rated health status had significantly higher understanding levels of B2-1, B2-2 and B2-6 than those with a “good” or “fair” status. Respondents with “very good” or “good” self-rated health status had a significantly higher understanding level of B2-13 than those with a “fair” status. Respondents with “very good” self-rated health status had a significantly higher understanding level of B2-7 than respondents with “fair” status. Similar to understanding levels but to a lesser extent, respondents’ self-rated health status demonstrated differences in agreement levels of other ecological benefits. Respondents with “very good” and “good” self-rated health status had a significantly higher agreement level of B2-2 than those with “fair” status.

4. Discussion

4.1. Childhood City Living Generated Better Self-Rated Health Status

Most previous studies started from the social environment of childhood, such as family structure and size, as well as the corresponding adverse personal experiences (including domestic violence, parental mental illness, sexual abuse, poverty, etc.) to explore the long-term impact of the environment on health. However, we started from the objective and extrinsic living environment in childhood. We divided the living environments into urban, suburb, and village types. In childhood, we found that residing in different living environments could usher different self-rated health status. Residents who used to live in the city returned a healthier status than those living in the village.

The explanation for this association between past living environments and present perception of one’s health status could be traced to the socioeconomic conditions of the villages vis-à-vis the cities some decades ago in China. With the attention then focused squarely on national economic recovery and development after a long period of wars, resources tended to move one way from rural areas to cities, resulting in a contrasting rural-urban dichotomy. The recent policy of rural-urban integration would require time to take effect, leaving the suburban and rural areas developing at a relatively slow pace and echoing the need for improved coordination in resource allocation. Meanwhile, many cities have grown rapidly on the economic, social and environmental fronts. As a result, the cities could increasingly provide a safe and harmonious social environment, accelerated economic development, better medical care, and more green spaces with good accessibility [42,54,55].

Such accessibility to comprehensive urban enhancements, including water safety, sanitation, food quality, and health care, would generally provide residents with a healthy feeling and improved health conditions. The prolonged exposure to a generally health-promoting ambience since childhood would be conducive to nurturing confidence in the current self-rated health status [56,57]. In contrast, people growing up in the village were often deprived of these health-related ingredients. The extended period of health deficit in childhood would usher a lingering effect on adulthood. It is understandable for them to rate their health status at a relatively low level.

However, we did not find differences in self-rated health status among residents with reference to current living environments. This result may be related to the increasing closure of the rural-urban gap, including the health-related environmental factors and health care. The 17th National Congress of the Communist Party of China in 2007 put forward the strategy of “coordinating urban and rural development”, and the 19th Congress in 2017 instituted the “rural revitalization” scheme. These strategies promoted the development of the rural economy, living environments, transportation, education, medical facilities, etc., thus reducing the rural-urban disparities [58]. The decline in health inequalities would foster the health conditions of the rural population. Hence, they would be inclined to express a relatively high self-rated health status.

4.2. Perceiving Direct UGS Ecological Benefits Better than Indirectly Ones

Previous studies of residents’ perception of UGS ecosystem services paid more attention to cultural services. We accorded more emphasis on thermal benefits, closely related to climate change and health [14,59]. We found that respondents had particularly strong perceptions of specific thermal benefits, such as providing cool shading in hot sunny weather, lowering the building’s surface temperature, and keeping the indoor areas cool by green roof and green wall. These benefits are directly related to cooling in the outdoor and indoor ambience. They are related to the exposure and experience of the daily and immediate environs that could be directly detected and felt hedonically by human sensory faculties. The benefits that could suppress thermal stress and bring thermal comfort explicitly and with obvious impingement on human sensory organs attracted more attention. It can be noted that residents are aware of the cooling functions obtained by the innovative wrapping of the building envelope by green roof and green wall.

In contrast, the perceptions of indirect UGS thermal benefits were comparatively weak. They included “the cool island effect of parks can extend to adjacent areas” and “help adapt to climate change”. The item “Create cool island effect” and “ameliorate urban heat island effect” also solicited relatively low scores. Proper comprehension of the higher-order and less direct thermal benefits demands a deeper understanding of the knowledge base. People would be less amenable to appreciate these indirect grey-box thermal sensations with a spatial and temporal detachment from the body and mind. This result reflected that the respondents might have a limited grasp of the relatively complex and intricate conceptual basis and linkages in the urban thermal regime. Whereas the on-site cooling benefits of green enclaves could be readily appreciated, the off-site, spilt-over and relatively remote extension of cooling or suppression of warming might have escaped their awareness realm.

Respondents were probed for their perceptions of other UGS ecological benefits. Items subsumed under the sub-category of general environmental-landscape benefits (Table 1), such as “removing air pollutants to improve air quality”, “offering natural seasonal changes”, and “absorbing carbon dioxide and mitigating greenhouse effect”, secured high understanding and agreement levels. The ecological benefits that bring evident effects and are widely known tend to solicit higher understanding and agreement levels.

However, perceptions of indirect UGS benefits under the sub-categories of water regulation benefits and biodiversity conservation benefits were weak. They are represented by items such as “allow more wildlife to dwell and forage in cities” and “reduce investments in stormwater drainage infrastructure”. Similar to thermal benefits, understanding these indirect items requires broader and more profound scientific knowledge. Whereas citizen science penetration has successfully popularized the basic knowledge on UGS benefits, the relatively more esoteric domains are inadequately grasped.

Our results differed from some recent cognate studies. Tian et al. (2020) found that residents had the highest perception level of climate regulation benefits of UGS, followed by cultural services, air filtration, water regulation and biodiversity conservation [34]. Rupprecht et al. (2015) found that residents were more inclined to perceive biodiversity conservation, air pollution abatement, landscape enhancement, and opportunities for children to play and acquire nature experience [33]. The divergence could be related to the questionnaire design and inherent differences in the study area. Tian et al. (2020) studied the residents of three major cities in the Yangtze River Basin and focused on perceptions of five UGS ecosystem services [34]. Rupprecht et al. (2015) assessed residents of Brisbane and Sapporo with similar urban planning by concentrating on perceptions of UGS leisure and environmental benefits [33].

Residents have indicated differential perceptions of UGS benefits, emphasizing some but giving less attention to others. Some measures can be adopted to reduce these differences and address the inadequate comprehension of some essential ecological functions. For instance, the aesthetic and ecological quality of UGS can be further improved to trigger more residents to contact and experience the natural companions and augment perceptions of UGS benefits [14]. UGS can be designed catering to residents’ needs and fostering more frequent contact with natural ingredients. Specific means can include improving access to UGS venues by foot traffic and public transport, increasing the tree and vegetation biomass and diversity, and boosting a wide range of ecological benefits.

Moreover, a well-designed UGS with diverse natural endowments offers an excellent and convenient living classroom for teaching life, ecological and environmental sciences. It can vividly demonstrate the diversities, intricacies and regularities of biological factors, processes and patterns. UGS can be more earnestly used for field studies, which can improve understanding and agreement levels of benefits and cultural services [31,60,61].

4.3. Living Environments at Different Life Stages Shaping Perceptions of UGS Ecological Benefits

In this study, we found that residents who lived in the village in childhood had lower understanding levels of the UGS cooling and energy-saving benefits than those living in the city and suburb. Some decades ago, village residents were relatively poor. They would prioritize using their limited incomes to acquire essential items such as food and clothing and could not afford air conditioners. As a result, they had an insufficient understanding of the connection between UGS and air conditioning energy consumption. Living in the countryside means regular exposure to nature and greenery; hence, they would not need to be concerned about the lack of nature and the corollary need to satisfy the innate desire to establish contact with nature. If they were not deprived of nature, they would not emphasize it as their urban counterparts.

The cooling benefits of green walls were better understood by people who lived in the suburb during childhood than those living in the city. The suburbs were closer to nature with more trees, other vegetation and fauna and less impermeable and hot sealed land covers. Children growing up in such environments were more likely to perceive the cooling effects of vegetation shade and evapotranspiration. They would also have opportunities to learn at first hand other ecological benefits. In urban areas with limited space at the ground level for greening, vertical greening offers new opportunities to compensate for the lack of green infrastructure [62,63]. Green roofs and green walls can be actively promoted by publicizing their benefits and know-how and providing incentives to encourage installation.

Residents currently living in the city had higher perception levels of some UGS ecological benefits than those living in the village. The well-recognized benefits included providing shading, cooling effect of green roofs, mitigating the heat island effect, and enhancing urban biodiversity. Such rather keen awareness could be related to the increasingly intense and widely-known urban heat island effect, which has raised urban temperatures to induce discomfort and heat-related morbidity and mortality. Urban residents were more likely to compare and contrast the heat island in built-up areas vis-à-vis the cool island of parks. In comparison, villages seldom have roof greening and large artificial green patches such as parks. Thus, village residents had little need to obtain ecological benefits from such artificial conceptions of urban greening. Hence, they would be less aware of the UGS cooling and other ecological functions. Public green spaces could be established in villages situated near cities to serve both city and country folks. The connection between urban and rural green areas in the form of an extensive green space network with high connectivity can facilitate wildlife movements, forage and breeding [64]. Such linkages can promote learning about the village domain in the interest of narrowing the rural-urban gap.

4.4. Good Self-Rated Health Status Begetting Better Perceptions of UGS Ecological Benefits

Residents’ self-rated health status had a significant impact on their perceptions of UGS ecological benefits. Especially, residents with “very good” self-rated health status had a significantly better understanding of the benefits of providing shading, storing carbon, purifying air, offering habitats, furnishing variegated natural colors and configurations, collecting rainwater, and replenishing groundwater. Residents who reported “good” self-rated health status tended to use UGS more frequently. UGS could play an important role in residents’ health, including: (1) Providing sites for physical activities, increasing the frequency of physical activities, and enhancing physical fitness by improving respiratory function and promoting blood circulation [65,66,67]; (2) Regulating nervous system functions, relieving stress, restoring attention through neuroendocrine pathways, and in general augmenting mental health [68,69]; (3) Promoting interpersonal communication and social interactions, enhancing social harmony and cohesion, boosting the sense of security and reducing the feeling of loneliness [70,71]. Through these positive mechanisms, residents could cultivate and foster more confidence in their health conditions. In the process of using the UGS, they would acquire more experience of ecological benefits.

Urban planners and managers could find ways to increase residents’ frequency and duration of using UGS to more fully realize their crucial function as a valuable community health resource. The childhood living environment has a unique role in shaping residents’ self-rated health status and perceptions of UGS benefits. The primary concern is to resolve the economic and ecological inequities in the living environments of urban, suburb and village areas. Knowledge transmission through the citizen science mode offers a way to enhance residents’ recognition of the under-rated indirect ecological benefits. Measures may include enriching the school curriculum and encouraging using UGS as outdoor educational venues. Providing UGS with diverse natural endowments and recreational facilities could raise patronage and allow inclusive enjoyment by different social groups.

5. Limitations and Further Studies

As the data did not align with the normal distribution requirement of the more powerful parametric statistical tests, we had to apply the less powerful nonparametric techniques to probe the relationships. The depth of the investigations regarding the relationships between variables could be restricted.

The study was a first attempt to investigate the perception of the UGS in the Beijing metropolis, China’s capital city. Due to limitations in resources, we focused our work on the general public and the fundamental factors. To follow up, the perceptions of different socioeconomic groups and different types of UGS deserve to be explored. The health status and childhood and present living environments could be evaluated using a more elaborate typology.

6. Conclusions

Assisted by questionnaire surveys and non-parametric statistical tests (Mann-Whitney test and Kruskal-Wallis test), this paper evaluated the relationships among childhood and current living environments, self-rated status and the perceptions of the UGS ecological benefits. Our results indicated that: (1) Direct UGS ecological benefits were more easily perceived by respondents than indirect types. The benefits that could suppress thermal stress and bring thermal comfort explicitly and with obvious impingement on human sensory organs attracted more attention; (2) Living environments at different life stages shaped perceptions of UGS ecological benefits. In childhood, residents who lived in the village had lower understanding levels of the UGS cooling and energy-saving benefits than those living in the city and suburb. The cooling benefits of green walls were better understood by people who lived in the suburb during childhood than those living in the city. Compared to residents living in the village, those currently living in the city had higher perception levels of some UGS benefits, including providing shading, cooling effect of green roofs, mitigating the heat island effect, and enhancing urban biodiversity; (3) The self-rated health status of respondents who lived in the city was significantly better than those who lived in the village and suburb in childhood; and (4) Residents with “very good” self-rated health status had a substantially better understanding of UGS benefits regarding shading, providing varied colors and habitats, storing carbon, purifying air, and collecting rainwater. The findings could inform the UGS policy-makers of residents’ latent outlooks and expectations regarding the multiple benefits and the strategy to refine promotional programs to encourage UGS visitation to realize and enjoy the benefits.