Restorative benefits of urban green space: Physiological, psychological restoration and eye movement analysis

The mitigating effect of street trees, urban flora, and the suburban environment on seasonal peak UV indices: A case study from Brisbane, Australia

Tree shade, particularly shade that obscures direct sunlight near peak periods of midday solar exposure can have a pronounced effect on potentially harmful ultraviolet radiation, and in turn, strongly influence the maximum daily UV index (UVI). In this study, the seasonal influence of tree shade on the UVI is evaluated from 210 hemispherical sky view images collected alongside public walkways and footpaths from 10 residential Brisbane suburbs. The effective sidewalk UV index is calculated underneath planted tree canopies, adjacent residential gardens, buildings and background tree species. Results are presented with respect to seasonal variations in the diurnal solar elevation for each month of the year at Brisbane's latitude. The research also examines the total reduction in UVI due to the presence of individual tree species, showing reductions in the midday UVI of up to 91% of an equivalent unimpeded sky hemisphere when overhead tree canopies are present. Important footpath tree species for peak midday UVI mitigation include Pongamia pinnata, Xanthostemon chrysanthus, Senna siamea, and Libidibia ferrea. The planting and maintenance of existing tree species already growing alongside residential Brisbane streets will improve the shade characteristics of suburbs and enhance UV protection for local residents.

Monitoring tree canopy dynamics across heterogeneous urban habitats: A longitudinal study using multi-source remote sensing data

Urban trees have attracted increasing attention to serve as a green prescription for addressing various challenges facing human society like climate change and environmental deterioration. However, without healthy growth of urban trees, they cannot service any environmental, social, and economic benefits in a sustainable manner. By monitoring the canopy development, the tree growth dynamics in different urban habitats can be detected and appropriate management approaches can be executed. Using the Kowloon Peninsula, Hong Kong, as a case, this study explores how remote sensing data can help monitor and understand the impacts of heterogeneous urban habitats on tree canopy dynamics. Four algorithms based on WorldView-2 satellite image are compared to optimize the canopy segmentation. Then the individual tree canopy is integrated with Sentinel-2 satellite data to obtain canopy growth dynamics for each season from 2016 to 2020. Three indicators are applied to reflect tree canopy status, including the fluorescence correction vegetation index (FCVI, tracking leaf chlorophyll density), the soil adjusted total vegetation index (SATVI, measuring the density of woody branches and twigs), and the normalised difference phenology index (NDPI, capturing canopy water content). And four heterogeneous habitats where urban trees stand are specified. The results revealed that urban trees show varying canopy growth status, in a descending order from natural terrains, parks, residential lands, to road verges, suggesting that urban habitats curtail trees' growth significantly. Additionally, two super-typhoons in 2017 and 2018, respectively, caused serious damages to tree canopy. Relevant resiliency of tree varies, echoing the sequence of canopy growth status with those in road verges the least resilient. This study shows how remote sensing data can be used to provide a better understanding of long-term tree canopy dynamics across large-scale heterogeneous urban habitats, which is key to monitoring and maintaining the health and growth of urban trees.

Proximity to public green spaces and depressive symptoms among South African residents: a population-based study

BACKGROUND

Exposure to green spaces has been suggested to improve mental health and may reduce the risk of depression. However, there is generally limited evidence on the association between green spaces and depression originating from low-and middle-income countries and Africa in particular. Here, we investigate the association between proximity to public green spaces and depressive symptoms among residents of Gauteng Province, South Africa.

METHODS

We used data from the 2017/2018 Gauteng quality of life survey. We included all individuals aged 18 years or older residing in the nine municipalities of Gauteng Province that completed the survey (n = 24,341). Depressive symptoms were assessed using the Patient Health Questionnaire-2. Proximity to public green spaces was defined as self-reported walking time (either less or greater than 15 min) from individuals' homes to the nearest public green space. To assess the association between access to public green spaces and depressive symptoms, we used mixed-effects models, adjusted for age, sex, population group (African, Indian/Asian, Coloured (mixed race), and White), educational attainment, and municipality. We additionally performed stratified analyses by age, sex, educational attainment, and population group to evaluate whether associations differed within subgroups. Associations are expressed as prevalence ratios (PR) and their 95% confidence intervals (95% CI).

RESULTS

We observed a 6% (PR = 0.94, 95%CI = 0.92-0.96) prevalence reduction in depressive symptoms for individuals who reported that the nearest public green space was less than 15 min from their homes as compared to those who reported > 15 min. After stratification, this inverse association was stronger among females, individuals aged 35-59 years,those with higher levels of educational attainment, and Coloured individuals as compared to their counterparts.

CONCLUSION

Our findings suggest that public green spaces close to residential homes may be associated with a reduction in the occurrence of depressive symptoms among urban populations in resource-constrained settings like South Africa.

Exploring the effect of different typical plant community on human stress reduction: a field experiment

Research has demonstrated the positive effect of natural environment on human restoration and well-being. Time spent in nature can often alleviate both physiological and psychological stress. However, few studies have discussed the environmental health effects of the nature's components and characteristics. Sixty volunteers were recruited and one manufactured environment and five different natural environments were randomly assigned to them, including coniferous forests (pure coniferous forest-PC and mixed coniferous forest-MC), broad-leaved forests (pure broad-leaved forest-PB and mixed broad-leaved forest-MB), and mixed forest (mixed coniferous and broad-leaved forest-MCB). Each volunteer sat in a built or natural environment and looked around the environment for 15 min. Physiological (HR, HRV, BP, pulse rate and salivary cortisol) and psychological indicators (POMS and STAI) were used to evaluate the changes in their stress level. Results indicated a strong difference in HR, HRV, POMS and STAI between the built and natural environment, which showed that natural environment can lower the stress level. MC had the best effect on relieving physiological stress, whereas MCB is most successful in improving emotional state and reducing anxiety. Broad-leaved forest and mixed forest significantly affected the DBP and vigor level of the subjects, respectively. While coniferous forest did significantly increase the concentration of salivary cortisol in subjects. The study confirmed that compared to the built environment, the natural environment can relieve the human body's physical and psychological stress and negative emotions, while significantly increasing vitality. And different plant communities also have different effects on the physiological and psychological indicators of the subjects. These results will provide scientific basis for the construction and improvement of urban green space environment.

The impact of virtual reality natural and built environments on affective responses: a systematic review and meta-analysis

This study aims to evaluate the extent to which virtual reality (VR) natural and built settings affect emotional states. Web of Science, SCOPUS, and PubMed were searched for relevant articles prior to February 2022. Of 15 articles identified for systematic review, 6 met the inclusion criteria for meta-analysis (studies with only pre- and post-condition measures of the Positive and Negative Affect Schedule (PANAS) were included). Both positive affect (g = 0.20, p = 0.001) and negative affect (g = - 0.30, p = 0.001) change scores for the VR natural environment were statistically significant. On the other hand, change scores for VR built environment were not significant in both positive affect (g = - 0.08, p = 0.355) and negative affect (g = - 0.08, p = 0.058). The findings revealed that, in addition to a VR natural environment, a VR built environment is capable of providing restorative experiences against negative mood in some circumstances.

Exploring the association between self-reported and objective measures in search of the restorative quality of natural environments: a systematic review

The benefits of nature contact for psychophysiological restoration have sparked a surge of scientific attention in recent years. The diverse psychophysiological mechanisms of stress recovery make assessment with a single marker impractical. The majority of restoration research employs a holistic approach, including subjective psychological and objective physiological measures concurrently. However, this association has not been decisively supported by empirical studies. The purpose of this systematic review is to determine the degree to which subjectively experienced restoration, as measured by self-reported scales, is associated with actual physiological changes. Searches for peer-reviewed primary research articles were conducted in SCOPUS and PubMed, returning 216 papers; the final synthesis includes 21 empirical studies published between 2008 and 2022. Findings show that there is a strong association between subjective and objective measures of restoration. Further analysis verified that using concurrently self-reported and objective measures in measuring restoration, notably the associations of Profile of Mood States (POMS), Perceived Restorativeness Scale (PRS), and Positive and Negative Affect Scale (PANAS) with Blood Pressure (BP) and Heart Rate (HR), resulted in the highest degree of consistency. However, there were negligible inconsistent associations, which were mainly reported by Restoration Outcome Scale (ROS) in psychological indicators and Salivary Cortisol (SC) and Electroencephalography (EEG) in physiological indicators. This suggests that the results of research that uses these measures simultaneously should be interpreted with caution.

Healthy Patients, Workforce and Environment: Coupling Climate Adaptation and Mitigation to Wellbeing in Healthcare

Climate change threatens the health of all Australians: without adaptation, many areas may become unlivable, in particular the tropical north. The Northern Territory (NT) health workforce is already under colliding operational pressures worsened by extreme weather events, regional staff shortages and infrastructure that is poorly adapted to climate change. The H3 Project (Healthy Patients, Workforce and Environment) explores nature-based interventions in the NT health sector aiming to strengthen the resilience and responsiveness of health infrastructure and workforce in our climate-altered future. The H3 Project engaged the health workforce, climate researchers and the wider community, in recognition that meaningful and timely climate action requires both organization-led and grassroots engagement. We recruited campus greening volunteers and sustainability champions to Royal Darwin Hospital (RDH) to develop strategies that enhance climate adaptation, build climate and health literacy, and incentivize active mobility. We implemented low-cost biophilic design within the constraints of legacy healthcare infrastructure, creating cool and restorative outdoor spaces to mitigate the impacts of heat on RDH campus users and adapt to projected warming. This case study demonstrated substantial cooling impacts and improved local biodiversity and hospital campus aesthetics. We collaborated with Indigenous healers and plant experts to harness the synergy between Aboriginal people's traditional knowledge and connectedness to land and the modern concept of biophilic design, while seeking to improve hospital outcomes for Indigenous patients who are both disconnected from their homelands and disproportionately represented in NT hospitals.

Restorative Effects of Biophilic Workplace and Nature Exposure during Working Time: A Systematic Review

The work environment plays a crucial role in the health and performance of employees. The growing interest in workers' well-being has driven the inclusion of nature in workplaces, despite many employees spending most of their time indoors, away from nature. Studies show that biophilic design in offices can have positive effects and promote workers' well-being. However, research on the beneficial effects of nature exposure in the workplace is limited and scattered. Thus, the aim of this systematic review was to consolidate current knowledge on the restorative effects of nature exposure on workers during work activities. Different types of exposure, both outdoors and indoors, were considered, with a focus on outcomes related to well-being, motivation, job satisfaction, and work performance. Out of the initially identified 1225 articles, only 16 met the criteria for analysis. Although the analysed studies provided compelling evidence regarding the restorative effects of nature exposure in the workplace, the review also points out gaps and limitations concerning the number of specific studies in this area and the need to adequately assess the sensory dimensions involved in these effects. Conducting more comprehensive and multidimensional investigations into the impacts of nature on the work environment could contribute to guiding more effective design strategies and creating healthier and more productive workplaces for employees.

"Green transit-oriented development": Exploring the association between TOD and visible green space provision using street view data

Environmental inequalities generated by transit-oriented development (TOD) are of planning and policy relevance in developing countries. Existing literature has pointed out that TOD has the effect of 'place making', which means the newly developed transit systems may be able to change the environment and amenities of a certain area. While previous studies have largely focused on environment hazards such as noise and pollution induced by transit systems, scant attention has been paid to visible green space provision at station areas. This study develops a new and systematic framework to assess potential disparities in quality and quantity aspects of visible green space provision around subway stations. We explore the effects of TOD on visible green space provision around subway stations using spatial regression models. The results show that there are disparities in visible green space provision around subway stations, but such disparities tend to fade with distance away from stations. We also find that population density, land use mix, intersection density and bus stop density are significantly associated with quantity and quality aspects of visible green space provision around subway stations.

Elucidating and Expanding the Restorative Theory Framework to Comprehend Influential Factors Supporting Ageing-in-Place: A Scoping Review

Exposure to stress and attention fatigue resulting from changes in capabilities and residing in environments that do not align with individual needs can adversely impact older adults' mental health and complicate ageing-in-place. Research into the psychological restoration process can help assist in alleviating these issues. Existing research on restoration perspectives has predominantly centred on university students and lacks comprehensive insights into older adults. Consequently, this study seeks to acquire a deeper understanding of the restorative theory framework within the context of ageing populations. We identified and analysed thirty-nine papers on the restoration process of older adults employing the scoping review method. Our findings indicate that adjustments to the general restorative theory framework are imperative for ageing populations. By incorporating additional features-such as being with and familiarity-the framework can more effectively support the development of age-inclusive neighbourhoods that enhance the mental health of the older population and facilitate healthy ageing-in-place. While more in-depth research is required on the restoration process of older adults, this research marks the initial in adapting the general framework to ageing populations. Furthermore, insight is given into how the adapted framework can contribute to help address the challenges of global ageing and support ageing-in-place.

Effect Modifications of Overhead-View and Eye-Level Urban Greenery on Heat-Mortality Associations: Small-Area Analyses Using Case Time Series Design and Different Greenery Measurements

BACKGROUND

The protective effect of urban greenery from adverse heat impacts remains inconclusive. Existing inconsistent findings could be attributed to the different estimation techniques used.

OBJECTIVES

We investigated how effect modifications of urban greenery on heat-mortality associations vary when using different greenery measurements reflecting overhead-view and eye-level urban greenery.

METHODS

We collected meteorological and daily mortality data for 286 territory planning units between 2005 and 2018 in Hong Kong. Three greenery measurements were extracted for each unit: a) the normalized difference vegetation index (NDVI) from Landsat remote sensing images, b) the percentage of greenspace based on land use data, and c) eye-level street greenery from street view images via a deep learning technique. Time-series analyses were performed using the case time series design with a linear interaction between the temperature term and each of the three greenery measurements. Effect modifications were also estimated for different age groups, sex categories, and cause-specific diseases.

RESULTS

Higher mortality risks were associated with both moderate and extreme heat, with relative risks (RRs) of 1.022 (95% CI: 1.000, 1.044) and 1.045 (95% CI: 1.013, 1.079) at the 90th and 99th percentiles of temperatures relative to the minimum mortality temperature (MMT). Lower RRs were observed in greener areas whichever of the three greenery measurements was used, but the disparity of RRs between areas with low and high levels of urban greenery was more apparent when using eye-level street greenery as the index at high temperatures (99th percentile relative to MMT), with RRs for low and high levels of greenery, respectively, of 1.096 (95% CI: 1.035, 1.161) and 0.985 (95% CI: 0.920, 1.055) for NDVI (p = 0.0193 ), 1.068 (95% CI: 1.021, 1.117) and 0.990 (95% CI: 0.906, 1.081) for the percentage of greenspace (p = 0.1338 ), and 1.103 (95% CI: 1.034, 1.177) and 0.943 (95% CI: 0.841, 1.057) for eye-level street greenery (p = 0.0186 ). Health discrepancies remained for nonaccidental mortality and cardiorespiratory diseases and were more apparent for older adults (≥ 65 years of age) and females.

DISCUSSION

This study provides new evidence that eye-level street greenery shows stronger associations with reduced heat-mortality risks compared with overhead-view greenery based on NDVI and percentage of greenspace. The effect modification of urban greenery tends to be amplified as temperatures rise and are more apparent in older adults and females. Heat mitigation strategies and health interventions, in particular with regard to accessible and visible greenery, are needed for helping heat-sensitive subpopulation groups in coping with extreme heat. https://doi.org/10.1289/EHP12589.

Seasonal Forest Changes of Color and Temperature: Effects on the Mood and Physiological State of University Students

In this study, we attempted to analyze the effect of color and temperature changes in the forest environment over time on the mood and physiological state of university students. The survey was conducted four times considering forest changes such as new leaf appearance and growth, autumn leaf changes, and fallen leaves. The participants' moods and physiological states were first evaluated in an indoor environment; a second evaluation was conducted after contact with the forest. The color visual information of the forest environment was analyzed through color extraction from photographs taken each survey day. The participants' moods and physiological states were measured using the Korean Profile of Mood States-Brief and a heart rate variability measuring device, respectively. Changes in the forest experience according to the season had an effect on university students' mood states. In particular, the effects of the spring forest experience included the relaxation of tension and the activation of vigor. This result is considered to be influenced by factors such as the season's temperature and the green color, which is predominant in the spring forest. However, no physiological changes were found in the participants according to each season. The results of this study can lead to greater consideration of the role of color in urban forest planning for universities and other public spaces.

Exploring the Predictive Potential of Physiological Measures of Human Thermal Strain in Outdoor Environments in Hot and Humid Areas in Summer-A Case Study of Shanghai, China

Whenever people spend time outdoors during hot weather, they are putting themselves in potentially stressful situations. Being able to predict whether a person is overheating can be critical in preventing heat-health issues. There is a clear relationship between body core temperature and heat health. However, measuring body core temperature is expensive. Identifying a non-invasive measure that could indicate a person's thermal strain would be valuable. This study investigated five physiological measures as possible surrogates: finger mean skin temperature (FSKT), finger maximum skin temperature (FMSKT), skin conductance level (SCL), heart rate (HR), and heart rate variability (HRV). Furthermore, they were compared against the results of participants' subjective thermal sensation and thermal comfort in a range of hot microclimatic conditions in a hot and humid climate. Results showed that except for SCL, each of the other four physiological measures had a positive significant relationship with thermal sensation, but a negative relationship with thermal comfort. Furthermore, through testing by cumulative link mixed models, HRV was found to be the most suitable surrogate for predicting thermal sensation and thermal comfort through a simple, non-invasive measure in outdoor environment in summer in a hot and humid area. This study highlights the method for predicting human thermal strain and contributes to improve the public health and well-being of urban dwellers in outdoor environments.

Urban green spaces and suicide mortality in Belgium (2001-2011): A census-based longitudinal study

BACKGROUND

Exposure to green spaces is associated with improved mental health and may reduce risk of suicide. Here, we investigate the association between long-term exposure to residential surrounding greenness and suicide mortality.

METHODS

We used data from the 2001 Belgian census linked to mortality register data (2001-2011). We included all registered individuals aged 18 years or older at baseline (2001) residing in the five largest urban areas in Belgium (n = 3,549,514). Suicide mortality was defined using the tenth revision of the World Health Organisation International Classification of Diseases (ICD-10) codes X60-X84, Y10-Y34, and Y870. Surrounding greenness was measured using the Normalized Difference Vegetation Index (NDVI) within a 300 m and 1,000 m buffer around the residential address at baseline. To assess the association between residential surrounding greenness and suicide mortality, we applied Cox proportional hazards models with age as the underlying time scale. Models were adjusted for age, sex, living arrangement, migrant background, educational attainment, neighbourhood socio-economic position. We additionally explored potential mediation by residential outdoor nitrogen dioxide (NO₂) concentrations. Finally, we assessed potential effect modification by various socio-demographic characteristics of the population (sex, age, educational attainment, migrant background, and neighbourhood socio-economic position). Associations are expressed as hazard ratios and their 95% confidence intervals (CI) for an interquartile range (IQR) increase in residential surrounding greenness.

RESULTS

We observed a 7% (95%CI 0.89-0.97) and 6% (95%CI 0.90-0.98) risk reduction of suicide mortality for an IQR increase in residential surrounding greenness for buffers of 300 m and 1,000 m, respectively. Furthermore, this association was independent of exposure to NO₂. After stratification, the inverse association was only apparent among women, and residents of Belgian origin, and that it was stronger among residents aged 36 or older, those with high level of education, and residents of most deprived neighbourhoods.

CONCLUSION

Our results suggest that urban green spaces may protect against suicide mortality, but this beneficial effect may not be equally distributed across all strata of the population.

Urban park use and self-reported physical, mental, and social health during the COVID-19 pandemic: An on-site survey in Beijing, China

The COVID-19 pandemic created unprecedented challenges for people's health. Studies have demonstrated the positive impact of urban green spaces, particularly urban parks, on physical and mental health. However, few studies have evaluated social health, which is a component of human health, and more understanding of the relationship between urban parks and human health during the COVID-19 pandemic is required. This study examined the effects of urban parks on people's health using a canonical correlation model. Physical, mental, and social health were the dependent health variables, and five factors related to urban parks were the independent variables. This study investigated 22 urban parks inside the Forth Ring Road in Beijing, China using a questionnaire survey. The results demonstrated a positive association between urban parks and human health during the pandemic. Distance to the parks, park area, and park size were positively correlated with physical, mental, and social health. Furthermore, frequency and duration of visits to urban parks were positively associated with mental health and contact with neighbors. The health effects of urban park use varied with park types and locations' urbanization background. These findings can provide insights for health-oriented urban park planning and construction.

Is health-related quality of life 1-year after coronary artery bypass graft surgery associated with living in a greener environment?

INTRODUCTION

Greenery in the residential environment and in the hospital has been associated with improved surgical outcomes and recovery. We investigated the association between the level of residential greenness of patients with coronary disease and their heart disease-related Quality of Life (HRQoL) 1-year after a coronary artery bypass grafting (CABG) surgery.

METHODS

Participants in a prospective cohort study who underwent CABG surgery at seven cardiothoracic units throughout Israel during the years 2004-2007 filled in the MacNew HRQoL one day before and one year after surgery. Successful recovery was defined as ≥0.5 increase in the MacNew score between baseline and follow-up. Exposure to residential greenness in 90 m and 300 m buffers around the patient's home was assessed with Linear Spectral Unmixing analysis of Landsat 30 m imagery.

RESULTS

The cohort comprised of 861 patients (22% female) with a mean age of 65.5 years, and 59.2% classified as low-income. In the total cohort, higher residential greenness was associated with an improvement in emotional HRQoL (OR = 1.33 (95%CI: 0.99-1.79)), adjusting for demographic and socio-economic factors, living in the periphery/center, presence of diabetes, attending cardiac rehabilitation following surgery, BMI, and change in physical fitness and depression over the 1-year follow-up. Although no association was found between greenness and change in the physical or social subscales, a positive association was specifically observed among the low-income patients for the global HRQoL score, OR = 1.42 (95%CI: 0.97-2.10), as compared to the higher-income patients, p for interaction = 0.03.

CONCLUSIONS

Residential greenness is associated with improvement in HRQoL 1-year after CABG surgery, but not the physical and social scales, only in low-income patients. Ensuring greenery in the living environment may act as a social intervention that supports human health and disease recovery.

An ecological dynamics perspective on designing urban nature environments for wellbeing and health-enhancing physical activity

The latest World Health Organization report on green and blue space and mental health (2021) calls for greater, and better, urban nature environments, i. e., “wilder” urban parks, tree-laden sidewalks, and overall presence of nature in the urban environment. Evidence shows that living close to and interacting with nature promotes benefits to numerous health and well-being indicators. The present article narratively reviews what are the aspects of urban nature environments that enhance health and wellbeing markers, which aspects are preferred among users and visitors of urban nature environments, and how can the benefits for health and wellbeing be understood from a theoretical perspective. Finally, guided by the ecological dynamics framework, suggestions are put forward on how designers and planners of urban nature environments can consider affordances to promote physical activity behavior, health and wellbeing; and how exercise and health researchers and professionals may channel the interaction of individuals with the nature environment in their interventions and programs.

The Perceived Restorative Quality of Viewing Various Types of Urban and Rural Scenes: Based on Psychological and Physiological Responses

Attention restoration theory argues that the type of visual scene is important; however, related research is mostly based on a dichotomous comparison between natural and urban environments. Few studies have evaluated complex scenes comprising both natural and artificial elements. Therefore, we compared the differences between four types of environments: urban artificial scenes, urban natural scenes, rural artificial scenes, and rural natural scenes—using a survey based on the Perceived Restorativeness Scale (PRS), perception complexity scoring, and eye tracking. Participants (N = 119) viewed photographs in a random order. The results showed significant differences between the visual landscape scores and eye-tracking data for each type of visual image: PRS, perception complexity, average fixation duration, and mean pupil size. Rural natural scenes had a higher restoration effect than the other scenes. Waterscapes and well-maintained vegetation had positive correlations between the typical landscape element indices and restorative benefits in different scene types. Contrastingly, weeds and hardscapes showed negative correlations, which can be attributed to the maintenance of these typical elements. The harmony of elements with circumstances in a scene was a key factor. The results provide a reference for urban and rural landscape planning and design to improve perceived restorative quality.