Blue space, health and well-being: A narrative overview and synthesis of potential benefits

Mechanisms of Impact of Blue Spaces on Human Health: A Systematic Literature Review and Meta-Analysis

Blue spaces have been found to have significant salutogenic effects. However, little is known about the mechanisms and pathways that link blue spaces and health. The purpose of this systematic review and meta-analysis is to summarise the evidence and quantify the effect of blue spaces on four hypothesised mediating pathways: physical activity, restoration, social interaction and environmental factors. Following the PRISMA guidelines, a literature search was conducted using six databases (PubMed, Scopus, PsycInfo, Web of Science, Cochrane Library, EBSCOHOST/CINAHL). Fifty studies were included in our systematic review. The overall quality of the included articles, evaluated with the Qualsyst tool, was judged to be very good, as no mediating pathway had an average article quality lower than 70%. Random-effects meta-analyses were conducted for physical activity, restoration and social interaction. Living closer to blue space was associated with statistically significantly higher physical activity levels (Cohen’s d = 0.122, 95% CI: 0.065, 0.179). Shorter distance to blue space was not associated with restoration (Cohen’s d = 0.123, 95% CI: −0.037, 0.284) or social interaction (Cohen’s d = −0.214, 95% CI: −0.55, 0.122). Larger amounts of blue space within a geographical area were significantly associated with higher physical activity levels (Cohen’s d = 0.144, 95% CI: 0.024, 0.264) and higher levels of restoration (Cohen’s d = 0.339, 95% CI: 0.072, 0.606). Being in more contact with blue space was significantly associated with higher levels of restoration (Cohen’s d = 0.191, 95% CI: 0.084, 0.298). There is also evidence that blue spaces improve environmental factors, but more studies are necessary for meta-analyses to be conducted. Evidence is conflicting on the mediating effects of social interaction and further research is required on this hypothesised pathway. Blue spaces may offer part of a solution to public health concerns faced by growing global urban populations.

Greenness may improve lung health in low-moderate but not high air pollution areas: Seven Northeastern Cities' study

INTRODUCTION

There is growing interest in the impact of greenness exposure on airway diseases, but the impact of greenness on lung function in children is limited. We aimed to investigate the associations between greenness surrounding schools and lung function in children and whether these associations are modified by air pollution exposure.

METHODS

Between 2012 and 2013, a cross-sectional survey and spirometry were performed among 6740 school children. Lung function patterns were determined as obstructive forced expiratory volume 1 s/forced vital capacity (FEV₁/FVC <0.8) or restrictive (FEV₁/FVC ≥0.8 but FVC <80% of predicted). School greenness was defined by Normalized difference vegetation index (NDVI) and soil-adjusted vegetation index. Nitrogen dioxide, sulphur dioxide and particular matter concentrations were assessed using a spatiotemporal model and national monitoring data. Two-level generalised linear models were used to investigate associations and interactions.

RESULTS

Overall, an IQR in NDVI within 500 m was associated with higher FEV₁ (+57 mL 95% CI 44 to 70) and FVC (+58 mL 95% CI 43 to 73). NDVI was similarly associated with 25% reduced odds of spirometric restriction (OR: 0.75, 95% CI 0.65 to 0.86). However, among children exposed to the highest compared with the lowest quartile of particulate matter, increasing NDVI was paradoxically associated with lower -40 mL FVC (95% CI -47 to -33, p interaction <0.05).

DISCUSSION

Our findings suggest that, in this study population, greening urban areas may promote lung health in low-moderate pollution areas but not in high air pollution areas. If the findings are replicated in other moderate-to-high pollution settings, this highlights a need to have a flexible green policy.

Contact with blue-green spaces during the COVID-19 pandemic lockdown beneficial for mental health

There is growing evidence that ecosystem services and especially the exposure to the natural world (blue-green spaces) have potential benefits for mental health and well-being. The COVID-19 pandemic and the measures adopted to control it provide a natural experiment to investigate the links between nature exposure and mental health under extreme conditions. Using a survey distributed online, we tested the following hypotheses: 1) People will show greater symptoms of depression and anxiety under lockdown conditions that did not allow contact with outdoor nature spaces; 2) Where access to public outdoor nature spaces was strictly restricted, (2a) those with green/blue nature view or (2b) access to private outdoor spaces such as a garden or balcony will show fewer symptoms of depression and anxiety, and a more positive mood. Based on 5218 responses from 9 countries, we found that lockdown severity significantly affected mental health, while contact with nature helped people to cope with these impacts, especially for those under strict lockdown. People under strict lockdown in Spain (3403 responses), perceived that nature helped them to cope with lockdown measures; and emotions were more positive among individuals with accessible outdoor spaces and blue-green elements in their views. These findings can help decision-makers in developing potential future lockdown measures to mitigate the negative impacts, helping people to be more resilient and maintain better mental health, using the benefits that ecosystem services are providing us.

Contact with blue-green spaces during the COVID-19 pandemic lockdown beneficial for mental health

There is growing evidence that ecosystem services and especially the exposure to the natural world (blue-green spaces) have potential benefits for mental health and well-being. The COVID-19 pandemic and the measures adopted to control it provide a natural experiment to investigate the links between nature exposure and mental health under extreme conditions. Using a survey distributed online, we tested the following hypotheses: 1) People will show greater symptoms of depression and anxiety under lockdown conditions that did not allow contact with outdoor nature spaces; 2) Where access to public outdoor nature spaces was strictly restricted, (2a) those with green/blue nature view or (2b) access to private outdoor spaces such as a garden or balcony will show fewer symptoms of depression and anxiety, and a more positive mood. Based on 5218 responses from 9 countries, we found that lockdown severity significantly affected mental health, while contact with nature helped people to cope with these impacts, especially for those under strict lockdown. People under strict lockdown in Spain (3403 responses), perceived that nature helped them to cope with lockdown measures; and emotions were more positive among individuals with accessible outdoor spaces and blue-green elements in their views. These findings can help decision-makers in developing potential future lockdown measures to mitigate the negative impacts, helping people to be more resilient and maintain better mental health, using the benefits that ecosystem services are providing us.

A Transdisciplinary Approach to Recovering Natural and Cultural Landscape and Place Identification: A Case Study of Can Moritz Spring (Rubí, Spain)

The perception of the quality of green and blue spaces can be key in the relationship between a community and its local landscape (i.e., place identification). The lack of transdisciplinary training and social-specific education of landscape architects regarding the complexity of landscape as a participative cultural artefact limits reaching the general population. Bridging this gap of landscape and place identification and evaluation by a local community was the main objective of the present case study conducted at an abandoned spring and seasonal stream area in Rubí (Spain). The "Steinitz method" of landscape evaluation was used as a participatory method to activate community members to learn about and express their visual preferences regarding this neglected landscape. Bottom-up interventions applying an "urban acupuncture" approach in the area identified as the least attractive by the residents were co-designed and combined with a top-down restoration of a nearby, existing but derelict and hidden, spring. In addition, before and after planning and implementing the intervention, we conducted surveys about the community perception, sense of belonging and use of the space. We observed that the lack of awareness of the inhabitants about this spring was an obstacle preventing the community from embracing the potential for health and wellbeing presented by the spring and adjacent landscape. Following the work, the landscape saw increasing use, and the historic spring was brought back to life as a resource to help people to improve their health and wellbeing.

Nature Exposure and Its Effects on Immune System Functioning: A Systematic Review

Given the drastic changes in our lifestyles and ecosystems worldwide, the potential health effects of natural environments have grown into a highly pervasive topic. Recent scientific findings suggest beneficial effects from nature exposure on human immune responses. This review aims at providing a comprehensive overview of literature published on immunomodulatory effects of nature exposure by inhalation of natural substances. A systematic database search was performed in SCOPUS and PubMed. The quality and potential bias of included studies (n = 33) were assessed by applying the EPHPP (Effective Public Health Practice Project) tool for human studies and the ARRIVE (Animal Research: Reporting of In Vivo Experiments) and SYRCLE (Systematic Review Centre for Laboratory Animal Experimentation) tools for animal studies. The synthesis of reviewed studies points to positive effects of nature exposure on immunological health parameters; such as anti-inflammatory, anti-allergic, anti-asthmatic effects or increased NK (natural killer) cell activity. Decreased expression of pro-inflammatory molecules, infiltration of leukocytes and release of cytotoxic mediators are outcomes that may serve as a baseline for further studies. However, partially weak study designs evoked uncertainties about outcome reproducibility and key questions remain open concerning effect sizes, duration of exposure and contributions of specific vegetation or ecosystem types.

Green and Blue Space Availability and Self-Rated Health among Seniors in China: Evidence from a National Survey

Many empirical studies have shown evidence of multiple health benefits provided by green and blue spaces. Despite the importance of these spaces, investigations are scarce in details for blue spaces rather than green. Moreover, most research has focused on developed regions. A limited number of studies on blue spaces can be found in China with a focus on the city level. Outcomes have been mixed due to varying research scales, methodologies, and definitions. This study relies on a national-level social survey to explore how the self-rated health (SRH) of senior individuals is associated with local green and blue space availability in urban and rural areas. Results indicate that the coverage ratio of overall green spaces and waterbodies around a resident’s home have marginal effects on SRH status in both urban and rural areas. In urban areas, living close to a park can is marginally beneficial for older people’s health. Regarding different types of blue spaces, the presence of a major river (within 0.3–0.5 km) or coastline (within 1 km and 1–5 km) in the vicinity of home negatively affects SRH among the elderly in urban areas. Close proximity to lakes and other types of waterbodies with a water surface larger than 6.25 ha did not significantly influence SRH. These findings not only evaluate general health impacts of green/blue space development on senior populations across the county but inform decision makers concerning the health-promoting qualities and features of different green/blue spaces to better accommodate an aging population in the era of urbanization.

How Can the Lived Environment Support Healthy Ageing? A Spatial Indicators Framework for the Assessment of Age-Friendly Communities

The Age-Friendly Cities and Communities Guide was released by the World Health Organization over a decade ago with the aim of creating environments that support healthy ageing. The comprehensive framework includes the domains of outdoor spaces and buildings, transportation, housing, social participation, respect and inclusion, civic participation and employment, communication and information, and community and health services. A major critique of the age-friendly community movement has argued for a more clearly defined scope of actions, the need to measure or quantify results and increase the connections to policy and funding levers. This paper provides a quantifiable spatial indicators framework to assess local lived environments according to each Age-Friendly Cities and Communities (AFC) domain. The selection of these AFC spatial indicators can be applied within local neighbourhoods, census tracts, suburbs, municipalities, or cities with minimal resource requirements other than applied spatial analysis, which addresses past critiques of the Age-Friendly Community movement. The framework has great potential for applications within local, national, and international policy and planning contexts in the future.