Green infrastructure and violence: Do new street trees mitigate violent crime?

Association between greenness and suicide attempts in patients with depression: A nationwide longitudinal cohort study

BACKGROUND

Although multiple emerging studies have suggested the relationship between greenness and mental health, evidence regarding associations among green space, suicide attempts, and depression is still limited. In this study, we aimed to estimate the association of greenness with suicide attempts in patients with depression.

METHODS

This study used the National Health Insurance Service database in South Korea to construct a cohort of patients diagnosed with depression during 2012-2013 (n = 677,498) with an 8-year follow-up period. Residential greenness was measured as the district-level annual average of the Enhanced Vegetation Index. The primary outcome was the suicide attempt, and categorized suicide attempts (non-violent and violent methods) were also examined. A Cox regression with time-varying variables was performed to assess the association between greenness and suicide attempts, and stratified analyses were conducted by sex, age, insurance premium, and disability status.

RESULTS

A higher level of greenness was associated with lower suicide attempts among patients with depression (HR: 0.789; 95% CI: 0.677, 0.918). The protective association was higher for suicide attempts by violent methods (HR: 0.733; 0.545, 0.987) than non-violent methods (HR: 0.812; 0.680, 0.970), based on point estimates. Among patients with depression, males, individuals aged 35-64 years, and Medical Aid beneficiaries showed a more prominent association with greenness.

CONCLUSIONS

This nationwide cohort study provides epidemiological evidence for the benefits of residential greenness in reducing suicide among patients with depression and suggests the appropriateness of public health policies for increasing green spaces.

Urban health inequality in shifting environment: systematic review on the impact of gentrification on residents' health

The impacts of changing neighborhoods, and the influence of neighborhood stability on residents' health have not received enough attention in the literature; one of the most important aspects is gentrification. Research on the impact of gentrification on residents' health has gradually increased in recent years, mainly from North America. Based on the guidelines of PRISMA 2020 and SCIE, 66 papers were included for analysis, six aspects of selected studies are discussed: the research design, theoretical framework, methods of analysis, definition and measurement of gentrification effects, and impact pathways. In general, most of the literature in this field can be seen as using an ecological research design, of which cross-sectional research accounts for a large proportion. The identified effects vary in their direction as well as strength due to difference in population, temporal, and geographical characteristics. Gentrification could affect health outcomes through the combination of economic, social, and physical environment factors. Existing research could be improved in the following aspects: (1) The definition and measurement of gentrification should be both generic and site-specific; Various measurement methods should be compared to enhance the robustness of the results. Furthermore, more consideration should be given to the impact of spatial issues; (2) As for health outcomes, it is suggested to expand the scope of the discussion of health outcomes and strengthen the biological explanation of the influencing mechanisms. It is also necessary to determine the research time points according to the characteristics of the incubation period of different diseases; (3) As for research design, applying longitudinal research design is more likely to improve the reliability; (4) Theoretical frameworks should be addressed to link the definition and measurement of gentrification, patterns of health outcomes, methodology and pathways.

Neighborhood segregation, tree cover and firearm violence in 6 U.S. cities, 2015-2020

Neighborhood segregation by race and income is a structural determinant of firearm violence. Addressing green space deficits in segregated neighborhoods is a promising prevention strategy. This study assessed the potential for reducing firearm violence disparities by increasing access to tree cover. Units of analysis were census tracts in six U.S. cities (Baltimore, MD; Philadelphia, PA; Richmond, VA; Syracuse, NY; Washington, DC; Wilmington, DE). We measured segregation using the index of concentration at the extremes (ICE) for race-income. We calculated proportion tree cover based on 2013-2014 imagery. Outcomes were 2015-2020 fatal and non-fatal shootings from the Gun Violence Archive. We modeled firearm violence as a function of ICE, tree cover, and covariates representing the social and built environment. Next, we simulated possible effects of "tree equity" programs, i.e., raising tract-level tree cover to a specified baseline level. In our fully-adjusted model, higher privilege on the ICE measure (1 standard deviation, SD) was associated with a 42% reduction in shootings (incidence rate ratio (IRR) = 0.58, 95% CI [0.54 0.62], p < 0.001). A 1-SD increase in tree cover was associated with a 9% reduction (IRR = 0.91, 95% CI [0.86, 0.97], p < 0.01). Simulated achievement of 40% baseline tree cover was associated with reductions in firearm violence, with the largest reductions in highly-deprived neighborhoods. Advancing tree equity would not disrupt the fundamental causes of racial disparities in firearm violence exposure, but may have the potential to help mitigate those disparities.

Green Infrastructure and Health

The health benefits of green space are well known, but the health effects of green infrastructure less so. Green infrastructure goes well beyond the presence of green space and refers more to a strategically planned network of natural and seminatural areas, with other environmental features designed and managed to deliver a wide range of ecosystem services and possibly to improve human health. In this narrative review, we found that small green infrastructure, such as green roofs and walls, has the potential to mitigate urban flooding, attenuate indoor temperatures and heat islands, improve air quality, and muffle noise, among other benefits, but these effects have not been linked directly to health. Larger green infrastructure has been associated with reduced temperatures, air pollution, and crimes and violence, but less so with health, although some evidence suggests that it may be beneficial for health (e.g., good health, decreased mortality). Finally, parks and street trees show many health benefits, but it is not clear if they can always be considered green infrastructure.

Memorial Parking Trees: Resilient Modular Design with Nature-Based Solutions in Vulnerable Urban Areas

Nature-based solutions (NbS) include all the landscape’s ecological components that have a function in the natural or urban ecosystem. Memorial Parking Trees (MPTs) are a new variant of a nature-based solution composed of a bioswale and a street tree allocated in the road, occupying a space that is sub-utilised by parked cars. This infill green practice can maximise the use of street trees in secondary streets and have multiple benefits in our communities. Using GIS mapping and methodology can support implementation in vulnerable neighbourhoods. In this research, we based vulnerability assessments for London, Rio de Janeiro, and Los Angeles on the following three indicators: extreme temperature, air quality, and flood-prone areas. Evidence is emerging that disadvantaged populations may live at higher risks of exposure to environmental hazards. The income and healthcare accessibility of neighbourhoods are the two indicators that will help us target these communities for a better and faster decision-making process. The contrast between the results and the 15-min city concept supports our detecting and prioritising neighbourhoods for MPTS implementation, among other NbS solutions integrated into a more inclusive and sustainable urban design.

A Theoretical Framework for Bolstering Human-Nature Connections and Urban Resilience via Green Infrastructure

Demand for resources and changing structures of human settlements arising from population growth are impacting via the twin crises of anthropogenic climate change and declining human health. Informed by documentary research, this article explores how Urban Resilience Theory (URT) and Human-Nature Connection Theory (HNCT) can inform urban development that leverages urban green infrastructure (UGI) to mitigate and meditate these two crises. The findings of this article are that UGI can be the foundation for action to reduce the severity and impact of those crises and progress inclusive and sustainable community planning and urban development. In summary, the URT promotes improvement in policy and planning frameworks, risk reduction techniques, adaptation strategies, disaster recovery mechanisms, environmentally sustainable alternatives to fossil fuel energy, the building of social capital, and integration of ecologically sustainable UGI. Further, the HNCT advocates pro-environmental behaviors to increase the amount and accessibility of quality remnant and restored UGI to realize the human health benefits provided by nature, while simultaneously enhancing the ecological diversity and health of indigenous ecosystems. The synthesis of this article postulates that realizing the combined potential of URT and HNCT is essential to deliver healthy urban settlements that accommodate projected urban population growth towards the end of the 21st-century.

Tree Ecosystem Services, for Everyone? A Compositional Analysis Approach to Assess the Distribution of Urban Trees as an Indicator of Environmental Justice

Trees provide a broad amount of ecosystem services in urban areas. Although it is well documented that trees are essential for the well-being and livability of cities, trees are often not evenly distributed. Studies have found that urban residents with a deprived socioeconomic status are associated with a lower coverage and access to urban trees in their communities, yet a fair distribution of trees contributes to the sustainability and resilience of cities. In this context, the environmental justice movement seeks to ensure equal distribution of green infrastructure and its benefits throughout a territory. The objective of this study is threefold: (i) to determine whether urban trees in Guadalajara, Mexico, are distributed equally; (ii) to assess the association between urban trees and socioeconomic status; and (iii) to introduce compositional data analysis to the existing literature. Due to the compositional nature of the data, compositional analysis techniques are applied. We believe this novel approach will help define the proper management of data used in the literature. The outcomes provide insights for urban planners working towards the Sustainable Development Goals to help eradicate the uneven distribution of urban trees in cities.

The Impact of Green Space on Violent Crime in Urban Environments: An Evidence Synthesis

Can the presence of green space in urban environments reduce the frequency of violent crime? To ascertain the evidence on this topic, we conducted an in-depth literature review using the PRISMA checklist. The search parameters included US articles written in English and published since 2000. More than 30,000 potential paper titles were identified and ultimately, 45 papers were selected for inclusion. Green spaces typically comprised tree cover, parks and ground cover. Criminal behaviors typically included murder, assault, and theft. The majority of the research reviewed involved quantitative methods (e.g., comparison of green space area to crime data). We extracted multiple mechanisms from the literature that may account for the impact of green space on crime including social interaction and recreation, community perception, biophilic stress reduction, climate modulation, and spaces expressing territorial definition. Recommendations are made for future research, such as meta-analysis of existing data and the development of grounded theory through qualitative data-gathering methods. By providing evidence that access to nature has a mitigating impact on violence in urban settings, city governments and communities are empowered to support these interventions.

Sustainability

This review on Sustainability covers selected 2018 publications on the focus of sustainability. It is divided into the following sections: (a) Water quantity; (b) Water quality; (c) Climate change and resilience; (d) Planning and ecosystem evaluation; (e) Life cycle assessment (LCA) applications; (f) Sustainable management; (g) Sustainability and asset management; (h) Sustainability in wastewater treatment; (i) Sustainable water and wastewater utilities; (j) Sustainable water resource management.

Green Infrastructure in the Urban Environment: A Systematic Quantitative Review

Increased levels of greenhouse gases released into the atmosphere, a legacy of the industrial revolution, population growth pressures, and consumerist lifestyle choices, are the main contributors to human-induced climate change. Climate change is commensurate of warming temperatures, reductions in rainfall, increased frequency of extreme weather events, and contributions toward declining public health trends. Green Infrastructure (GI) presents diverse opportunities to mediate adverse effects, while simultaneously delivering human health, well-being, environmental, economic, and social benefits to contemporary urban dwellers. To identify the current state of GI knowledge, a systematic quantitative literature review of peer-reviewed articles (n = 171) was undertaken using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) method. Temporal publication trends, geographical and geological information of research efforts, as well as research focus areas were recorded and reported against each article. The findings of this review confirm the research area to be in a state of development in most parts of the world, with the vast majority of the research emerging from the United States, Australia, and the United Kingdom. Cooler climates produced the majority of research, which were found largely to be of a traditional research article format. The GI research area is firmly dominated by foci comprising planning and policy, environmental and ecological, and social content, although modest attempts have also appeared in health and wellbeing, economic, and quality/performance of green infrastructure areas. Knowledge gaps identified by this review as requiring attention for research growth were identified as: (i) the ambiguity of terminology and the limited broad understanding of GI, and (ii) the absence of research produced in the continents of Asia and South America, as well as in regions with warmer climates, which are arguably equally valuable research locations as cooler climate bands.