Green Blue Space Research Articles

Modifying temperature-related cardiovascular mortality through green-blue space exposure

Green-blue spaces (GBS) are pivotal in mitigating thermal discomfort. However, their management lacks guidelines rooted in epidemiological evidence for specific planning and design. Here we show how various GBS types modify the link between non-optimal temperatures and cardiovascular mortality across different thermal extremes. We merged fine-scale population density and GBS data to create novel GBS exposure index. A case time series approach was employed to analyse temperature-cardiovascular mortality association and the effect modifications of type-specific GBSs across 1085 subdistricts in south-eastern China. Our findings indicate that both green and blue spaces may significantly reduce high-temperature-related cardiovascular mortality risks (e.g., for low (5%) vs. high (95%) level of overall green spaces at 99th vs. minimum mortality temperature (MMT), Ratio of relative risk (RRR) = 1.14 (95% CI: 1.07, 1.21); for overall blue spaces, RRR = 1.20 (95% CI: 1.12, 1.29)), while specific blue space types offer protection against cold temperatures (e.g., for the rivers at 1st vs MMT, RRR = 1.17 (95% CI: 1.07, 1.28)). Notably, forests, parks, nature reserves, street greenery, and lakes are linked with lower heat-related cardiovascular mortality, whereas rivers and coasts mitigate cold-related cardiovascular mortality. Blue spaces provide greater benefits than green spaces. The severity of temperature extremes further amplifies GBS's protective effects. This study enhances our understanding of how type-specific GBS influences health risks associated with non-optimal temperatures, offering valuable insights for integrating GBS into climate adaptation strategies for maximal health benefits.

Spatiotemporal dynamics and driving factors of green-blue space in High-Density Cities: Evidence from central Nanjing

Urban green–blue space (UGBS) plays a crucial role in Chinese cities, occupying more than half of the built-up areas. Understanding the spatiotemporal dynamics and driving factors of UGBS in central Nanjing during rapid urbanization is important for studying UGBS evolution in high-density urban-area environments, providing a fundamental basis for related research and policy formulation. This study utilized remote sensing images to estimate the extent of UGBS from 2000 to 2020 and analyzed the evolution using the intensity of area change, a land transfer matrix, the multi-order adjacency index, and a boosted regression tree model. This study revealed the spatiotemporal dynamics and driving factors of UGBSs in central Nanjing from 2000 to 2020: (1) between 2000 and 2020, there was a 4.0% net increase in the total area of UGBSs in central Nanjing. (2) UGBS primarily showed marginal-type expansion, accompanied by proximity-type expansion. Spatially, new green–blue patches tended to cluster around large pre-existing natural green–blue patches. Furthermore, the expansion of UGBS shifted from the urban periphery to the urban interior. (3) Natural factors exerted a greater influence (88.3%) than socioeconomic factors (11.7%) on the expansion of UGBS. Average annual radiation (43.4%), elevation (16.5%), slope (15%), aspect (13.4%), and population density (2.8%) were the primary driving factors. Our results contribute to understanding changes in UGBS and the driving factors behind these changes, thereby providing support for the future planning, protection, and sustainable development of UGBS.

Configuration characteristics of green-blue spaces for efficient cooling in urban environments

Optimizing green-blue space layouts is crucial in mitigating heat islands in built-up areas, and their cooling effects are influenced by both their own characteristics and the surrounding environments. However, the configuration characteristics of green-blue spaces with high cooling efficiency are still unclear. Additionally, the impact of surroundings on the generation and dispersion of cold sources has not been thoroughly studied. This study establishes a framework to identify the configuration characteristics of green-blue spaces with efficient cooling from four perspectives: occupation, dominance, regularity, and aggregation, and considering building environment, landscape composition, and adjacent influences to control surrounding influences. The Generalized Additive Model was employed to analyze the relationship between these factors and the mean temperature of corresponding units. The results demonstrate that efficient cooling landscape configurations vary among building densities. In low-density groups with an average building height of 3 floors and occupancy of 15 %, scattered small patches can enhance beneficial areas. Conversely, high-density groups with an average building height of 15 floors and occupancy of 32 % require more regular, large-scale patches. These findings offer tailored green-blue space layout strategies for Shanghai and similar large cities to achieve optimal cooling effects while considering limited land resources.

Visiting nature is associated with lower socioeconomic inequalities in well-being in Wales

Natural environments can promote well-being through multiple mechanisms. Many studies have investigated relationships between residential green/blue space (GBS) and well-being, fewer explore relationships with actual use of GBS. We used a nationally representative survey, the National Survey for Wales, anonymously linked with spatial GBS data to investigate associations of well-being with both residential GBS and time in nature (N = 7631). Both residential GBS and time spent in nature were associated with subjective well-being. Higher green-ness was associated with lower well-being, counter to hypotheses (predicting the Warwick and Edinburgh Mental Well-Being Scale (WEMWBS): Enhanced vegetation index β = − 1.84, 95% confidence interval (CI) − 3.63, − 0.05) but time spent in nature was associated with higher well-being (four hours a week in nature vs. none β = 3.57, 95% CI 3.02, 4.13). There was no clear association between nearest GBS proximity and well-being. In support of the equigenesis theory, time spent in nature was associated with smaller socioeconomic inequalities in well-being. The difference in WEMWBS (possible range 14–70) between those who did and did not live in material deprivation was 7.7 points for those spending no time in nature, and less at 4.5 points for those spending time in nature up to 1 h per week. Facilitating access and making it easier for people to spend time in nature may be one way to reduce socioeconomic inequalities in well-being.

Toward a Healthy Urban Living Environment: Assessing 15-Minute Green-Blue Space Accessibility

Exposure to green-blue space has been shown to be associated with better physical and mental health outcomes. The advent of COVID-19 has underlined the importance for people to have access to green-blue spaces in proximity to their residences due to pandemic-related restrictions on activity space. The implementation of the 15-min concept, which advocates that people should be able to reach locations of essential functions like green-blue spaces within 15 min of active travel, can bring green-blue spaces nearer to where people live. Nonetheless, there is still a lack of understanding of the social and spatial (in)equality in 15-min green-blue space accessibility by active travel in cities seeking to embrace the concept, such as Hong Kong. This study explores 15-min green-blue space accessibility by walking and cycling in Hong Kong to reveal the distribution of disadvantaged neighborhoods. The results show that neighborhoods in Kowloon’s districts are the most disadvantaged in accessing green-blue spaces within 15 min of active travel. Our study provides policymakers with valuable insights and knowledge conducive to formulating policies aimed at reducing inequality in 15-min accessibility.

Residential Greenspace Is Associated with Lower Levels of Depressive and Burnout Symptoms, and Higher Levels of Life Satisfaction: A Nationwide Population-Based Study in Sweden

Population-based studies of individual-level residential greenspace and mental health outcomes are still limited. Thus, the present study investigates greenspace–mental health associations—including depressive symptoms, burnout symptoms, and life satisfaction—in a population-based sample of adults, the Swedish Longitudinal Occupational Survey of Health, in 2016 (n = 14,641). High-resolution land cover of greenspace and green–blue-space was assessed at 50, 100, 300 and 500 m buffers around residential addresses. Higher residential greenspace and green–blue-space were associated with lower levels of depressive and burnout symptoms among non-working individuals and with higher life satisfaction in the whole study population, after controlling for age, sex, individual income, and neighborhood socioeconomics. The immediate residential-surrounding environment (50 m) consistently showed the strongest associations with the outcomes. Having a partner was associated with better mental health outcomes and with having more residential greenspace, and adjusting for this rendered greenspace–health associations mostly statistically non-significant. In conclusion, higher levels of greenspace and green–blue-space in the immediate residential-surrounding environment were associated with better mental health outcomes in the present study, which contributes additional nuances to prior studies. The importance of residential greenspace for public health, urban planning, and development is discussed.

Exposure to green-blue spaces and mental health: a retrospective e-cohort study in Wales

BackgroundGrowing cross-sectional evidence links access to green-blue spaces with mental health benefits, but studies at an individual level and at a national population scale are scarce. This gap can be addressed through the Secure Anonymised Information Linkage (SAIL) Databank, which allows household-level green-blue spaces access and exposure data to be linked to individual-level health-care use. MethodsWithin the SAIL Databank, an e-cohort of the population of Wales (2008–19) was created from green-blue space metrics and the Welsh Longitudinal General Practice database. Green-blue spaces metrics (derived from satellite imagery and planning data) included average ambient greenness within 300 m of the home (designated as the Enhanced Vegetation Index) and average access to green-blue spaces (designated as the number of green-blue spaces within 1600 m of the home). A validated algorithm was applied to create a common mental health disorder flag and linked to green-blue spaces exposure (ambient greenness and access) recorded for individuals not affected by common mental health disorders. We used multivariate logistic regression models to test the hypothesis that greater green-blue spaces exposure is associated with a reduced likelihood of a flagged common mental health disorder. Subgroup analyses were done for socioeconomic deprivation. FindingsThe e-cohort comprised 2 341 591 individuals (1 193 240 men and 1 148 351 women), aged 16 or over and registered with a general practice in the SAIL Databank. After adjusting for individual and area-level covariates, a unit increase in ambient greenness around the home and access to green-blue spaces within 1600 m were associated with lower odds of a common mental health disorder (adjusted odds ratio 0·11 [95% CI 0·11–0·12] for ambient greenness around the home and 0·47 [0·46–0·48] for access to green-blue spaces within 1600 m). A unit increase in ambient greenness was associated with reduced odds of a common mental health disorder for residents of the most deprived areas (n=473 410; 0·22 [0·20–0·24]) and of the least deprived areas (n=480 424; 0·07 [0·07–0·08]). InterpretationPeople with greater exposure to green-blue spaces were less likely to develop a common mental health disorder and the effect is modified by socioeconomic deprivation. This finding has implications for both public health policy and urban planning. This large, adult-population cohort provides sufficient power to examine variations between subgroups to investigate inequalities. FundingThe project was developed as part of independent research funded by the National Institute for Health Research (study number 16/07/07).

The cooling effect of hybrid land-use patterns and their marginal effects at the neighborhood scale

Mitigating urban heat islands in neighborhoods is one of the most important issues in landscape planning. Identifying land-use patterns with cooling effect and applying them in practice is a way to reduce neighborhoods’ temperature. However, there are relatively few relevant theoretical and practical studies at present. A combination of factors influences the thermal environment of a neighborhood. With the increasing complexity of neighborhood land-uses, the cooling effect of these factors is difficult to measure individually and need to be considered from a holistic perspective. What kinds of hybrid land-use patterns (HLPs) in neighborhoods have the cooling effect and are prone to creating cold islands? This is a big question to environmental optimization and sustainable development, and there has little discussion about it. To address this, this paper proposed a technical framework for delineating and analyzing the cooling effect of HLPs at the neighborhood scale. Taking Jinan City as an example, four indicators were selected to describe the characteristics of HLPs, including building surface ratio (BSR), green-blue space surface ratio (GBSR), impervious surface ratio (ISR), and average building height (MAH). With the K-Medoids clustering algorithm, ten HLPs were delineated, and their marginal effects were analyzed by the Boosting Regression Trees (BRT) model. The study found that HLPs dominated by high-rise buildings and by green-blue spaces had the most pronounced cooling effect; low- and mid-rise dominated HLPs showed a weak cooling effect when the mean GBSR reached 34%, and the cooling effect of green-blue space and impervious surface dominated HLPs are more obvious when the mean GBSR reached 48%. The technical framework proposed in this paper provides a new perspective on thermal environment research and heat island mitigation at the neighborhood scale, which is applicable to cities with various climatic backgrounds and landscape characteristics and of generalization value.

The right mix: Residential urban green-blue space combinations are correlated with physical exercise in a tropical city-state

Growing recognition of nature’s benefits to many aspects of human wellbeing has prompted the incorporation of both urban green and blue natural outdoor environments (NOEs) into cities. Amongst the many purposes of NOEs, promotion of physical exercise has been garnering interest, given the increasingly sedentary lifestyles of urban dwellers. However, studies rarely consider how different types of NOEs, let alone the combination of them, might affect the type and frequency of physical exercise conducted by urban residents. We use Singapore, a highly urbanised tropical nation with a considerable number of NOEs, as a case-study to address these gaps. We used a market research survey (n = 1519), geographic information systems, and generalised linear regression models to investigate the relationship between residential NOE cover, exercise-influencing sociodemographic factors, and outdoor exercise choice (i.e., if respondents exercised or not) and frequency of four types of physical exercises: walking, individual-based, team-sports, and overall exercise. For exercise choice, more people walked in areas with higher forest and scrub cover, and less in areas with just scrub. Less conducted individual-based exercise in areas with high unmanaged vegetation cover, and more conducted team-sports in areas with higher open-canopy managed vegetation cover. Amongst those who engaged in these exercises, managed vegetation cover is positively correlated with walking (open- and closed-canopy combined) and team-sports (open-canopy) frequency. Individual-based exercise frequency rose in areas with a mix of high open-canopy managed vegetation and blue space cover within 250 m from one’s home, and a mix of high managed treescape and forest cover 500 m from one’s home. Findings suggest that a specific mix of NOEs can promote the participation of different types of physical exercise. Integrating the right NOE types and combinations into urban residential spaces may thus help to mitigate sedentary lifestyles, boosting public health outcomes in city populations.

Community Attitude towards Urban Green-Blue Space and Perceived Cultural Ecosystem Benefits: A Preliminary Study at Taiping Lake Garden, Perak, Malaysia

blue spaces. Attitude towards green-blue space were also studied. However, little attention is given to perceived benefits and attitude components in ecosystem service research. This paper aims to examine community attitudes towards urban green-blue spaces and its association with perceived benefits based on cultural ecosystem services concept. A questionnaire was conducted among 31 respondents of local community at Taiping Lake Garden, Perak. The data were analyzed using Statistical Package for the Social Science (SPSS) which involving multiple regression to capture the effects of attitude components on perceived benefits. The findings suggest that overall attitudes of respondents had an excellent level of perceived attitudes toward urban green-blue space. However, among three sub-construct of attitudes, only cognitive attitude was found to be the dominant variable compared to conative and affective attitude that predicts perceived cultural ecosystem benefits. This indicates that if the community could enhance their positive attitudes toward their urban green-blue space, they may perceive higher cultural ecosystem benefits. Future research should continue to explore ways of enhancing positive attitudes among urban community as attitude may guide them to enhance their engagement in urban green-blue spaces.

Does green-blue space visibility improve physical activities and human health a systematic review

Background Research suggests that exposure to green and blue space (GBS) is significantly associated with improved health and wellbeing; however, the relationship between GBS visibility and health is still poorly understood. Objectives Conduct a systematic review to understand the strength and adequacy of the associations between GBS visibility and health. Identify the strengths and limitations of different approaches for measuring GBS visibility. Methods Following the PRISMA protocol, three databases (PubMed, Web of Science, and Scopus) were searched systematically to identify relevant studies published up to August 15, 2019. Based on a critical selection process and carefully selected eligibility and exclusion criteria, 17 studies were included in the review and synthesised. Results The reviewed studies showed strong, significant positive relationships between GBS visibility and health and wellbeing. Increasing GBS visibility improved mental health (e.g., reduced depression) and wellbeing (e.g., increased happiness). Physical health evidence was mixed, as visibility did not significantly reduce body mass index values for males and children, but visibility did significantly increase physical activities in adults and reduce body mass index values in females. Few studies identified associations between the variables based on age, gender, and socioeconomic conditions. The review indicated heterogeneity in the measurement of health outcomes and visibility (e.g., viewshed, street-view-image analysis). No single method of measuring visibility showed absolute strengths over the other methods. Conclusion The association between visibility and improved health and wellbeing is positive and significant, but the evidence was inadequate. Future studies should focus on (i) associations between GBS visibility and health in diverse populations and different geographic locations, (ii) the development of better visibility measurement methods, (iii) the use of a more objective measurement for health outcomes.

Structural investigation of ormolytes for EC devices: IR spectroscopic characterization and relation between viscoelastic properties, conductivity and optical modulation

Electrochromic (EC) devices assembled using two complementary optically active electrodes, i.e. sputtered tungsten (VI) oxide (WO3) and sol–gel substoichiometric nickel oxide–polyaniline (NiO1−x–PANI) films, were used for the evaluation of several ormolytes during coloring/bleaching switching. Electrolytes were prepared from bis end-capped bis(ethoxysilyl)/poly(ethylene oxide) di-uretanesil precursor via solvolysis and condensation with glacial acetic acid. Different amounts of mesylate imidazolium-based ionic liquid co-solvent were added to modify the viscoelastic properties of the ormolytes. An extensive IR spectroscopic investigation was conducted to follow the formation of a gel structure of di-urethanesil precursor through decrease of etoxysilyl modes (1165, 1103, 1079 and 955cm−1), remaining silanols (910cm−1), while the presence of silylacetate mode (1724cm−1) could not be ascertained unequivocally. Formation of siloxane bridging (prevailing T2 type) was confirmed independently by using 29Si NMR spectroscopy. X-ray diffraction showed an amorphous character of the electrolytes. Rheology measurements of the electrolyte were combined with the time-dependent determination of the conductivities (of the order of magnitude 10−4S/cm), and the dependence of the phase shift angle δ fitted using a five-parameter logistic function. It was found that adequate viscoelastic properties are essential (δ>0) in obtaining a sufficiently high conductivity for application in EC devices, and their cycling was examined up to 980 voltammetric and chronocoulometric cycles. The calculation of color coordinates revealed the shift of a⁎, b⁎ to green-blue space with coloration. The coloration efficiency (101st cycle) confirmed the differences in consistency of electrolytes, i.e. 74.3cm2/C for EC device with viscoelastic liquid-like electrolyte, but decreased to 54.7cm2/C for device with gel character of electrolyte.