Urban Green Spaces Research Articles

The Scale-Dependent Differences in Cooling Efficiency of UGS in Different Functional Areas: A Case Study of Xi’an, China

Urban green spaces (UGS) play a critical role in mitigating the urban heat island (UHI) effect and addressing climate change challenges through their cooling effects. Expanding green space and optimizing its layout are key strategies in urban planning. However, with limited land resources, maximizing cooling efficiency becomes crucial. While previous studies have yet to reach a consensus on the optimal UGS size threshold for achieving maximum cooling efficiency, this study employs high-resolution remote sensing imagery to extract 25,594 UGS patches in Xi’an and explores the scale dependency of UGS cooling effects. Results show that 54.20% of the patches exhibit a “cooling island effect”, reducing surface temperatures by 0.10 ± 0.13 °C to 1.66 ± 1.15 °C. A nonlinear relationship was observed between cooling intensity and UGS size, influenced by vegetation coverage and edge complexity. Further analysis reveals that medium-sized UGS have the highest cooling efficiency. These UGS were categorized into five functional zones to explore the dominant factors affecting cooling efficiency in each zone, and corresponding strategies for improvement were proposed. These findings provide insights into optimizing UGS layout and refining the cooling efficiency thresholds.

A Framework for Upgrading Contaminated Urban Land and Soil by Nature-Based Solutions: Demonstration with a Swedish Case

To move towards a circular economy and to meet the upcoming EU soil health legislation, both contaminated land and contaminated soil should be acknowledged as fragile and valuable resources to be restored and recycled to provide essential ecosystem services to humans. Underused, often contaminated land can be returned to beneficial use as urban greenspace (UGS) with the help of gentle remediation options (GROs). GROs are plant-, fungi-, bacteria-, and soil amendments-based risk management mechanisms that can also simultaneously improve soil functions and the provision of ecosystem services. This study (i) presents a framework including tools and methods for exploring opportunities for transforming brownfields to UGS using GROs to deal with soil contamination, (ii) demonstrates its application for a case study site in Gothenburg, Sweden, and (iii) presents stakeholders’ views on the suggested framework. This framework can support the transition of brownfields to UGS while recycling both land and soil and increasing the market value of the site and its surroundings. Stakeholders found the suggested framework useful but identified some challenges for its practical implementation, mainly associated with financial aspects and the existing practice and level of knowledge. Stakeholders also identified the need for additional practical tools to (a) make predictions about the time required for GROs to reach acceptable risk levels, (b) monetize non-market benefits such as ecosystem services for communicating benefits to decision-makers, and (c) provide support for plant and soil amendment selection for various GROs and contaminants.

Decadal Pattern of Built-up Expansion and its Consequences on Urban Green and Blue Space Fragmentation

Decadal Pattern of Built-up Expansion and its Consequences on Urban Green and Blue Space Fragmentation

Plant species selection for urban green spaces in arid lands: a new approach using ecosystem services and disservices

Plant species selection for urban green spaces in arid lands: a new approach using ecosystem services and disservices

Exploring the correlation between tree structure characteristics and carbon storage in historic gardens using TLS technology: a case study of Jian Xin Pavilions at Jingyi Park, Fragrant Hills Park

Historic gardens contain a greater number and variety of ancient trees, which are older, have unique forms, and larger volumes. These trees hold significant value in both natural ecosystems and cultural heritage. However, current research on the carbon sequestration value of ancient and non-ancient trees in historical gardens is relatively lacking. Based on the unique morphology and carbon storage estimation needs of ancient trees in historic gardens, this paper proposes a morphology-based point cloud single-tree segmentation method. This method can precisely extract the morphological structures of various tree species and accurately estimate their carbon storage. From the perspective of carbon sequestration, it evaluates the correlation between the structural characteristics and carbon storage of trees in historic gardens, as well as the potential changes in their carbon storage capacity.Using the Jing Yi Park’s Jian Xin Pavilions in Fragrant Hills Park as a case study, this method was applied to extract structural indicators of 116 ancient and non-ancient trees. The total carbon storage was found to be 19,171.13 kg, with an average carbon storage of 165.27 kg per tree. Among these, ancient trees accounted for 13,178.32 kg, or 68.74% of the total carbon storage. The study revealed that the correlation between tree age and carbon storage varied by species, and there were significant positive correlations between carbon storage and tree height, DBH, and canopy volume. Notably, there was a significant linear growth trend between DBH, canopy volume, and carbon storage. By 2030, the total carbon storage is projected to increase to 21,924.96 kg, with an annual average increase of 393.40 kg, representing a growth rate of 14.4%.The results indicate that studying the correlation between structural characteristics and carbon storage of aged trees in historical gardens can shed light on the important role of trees in sustainable carbon sequestration. The precise extraction of tree information through 3D digital technology and the prediction of carbon storage potential not only offer new perspectives for the conservation of cultural heritage in historical gardens, urban microclimate planning and design, and spatial management of carbon sinks and emissions but also have significant value for promoting the scientific management and protection of urban green spaces.

Trees Are a Major Foraging Resource for Honeybees in the City

Large cities are typically characterized by a mosaic of green spaces that hold a remarkable variety of native and “exotic” plants. Urban beekeeping has gained increasing popularity. In order to characterize the “urban” in the honey, pollen diversity in 50 honey samples from 18 apiary locations in Vienna, Austria, was microscopically analyzed. The relative abundances of each plant taxon were determined by counting out 500 individual pollen grains per sample. In total, 202 taxa could be identified, with a median of 46 per sample. Taxa richness and diversity differed significantly across three years but did not so between urban and suburban apiaries. Despite trees comprising only roughly a quarter of all taxa, the amount of tree pollen was disproportionally high. The invasive Ailanthus altissima was predominant in 15 out of 50 samples. Other important non-native and/or ornamental trees included Sophora japonica, Gleditsia triacanthos, Castanea sativa, Koelreuteria paniculata, and Liriodendron tulipifera. Urban honey from Central Europe may typically comprise pollen taxa from Europe, East Asia, and North America alike. The results of this study show that intentionally planted, managed urban green spaces can support stable foraging resources for pollinators in cities.

Greening urban areas in line with population density and ecological zone can reduce premature mortality

Urban green space and urban compactness are each important principles for designing healthy, climate-resilient cities. The principles can co-exist, but greening may come at density’s expense if not considered deliberately. Existing studies estimating health impacts of greening scenarios have not considered what level of greenness is attainable for different population densities. Here, using the square kilometer as the unit of analysis, we estimate non-accidental mortality that could be prevented among adults older than 30 by greening that small area to a level of greenness assumed to be attainable based on its broader urban area (N = 15,917 globally), population density, and ecological zone. Results suggest a large potential for urban greening even in the most population-dense parts of cities such that on average 54 deaths per 100,000 could be prevented per year in those areas. That estimate may be about 25% higher or lower due to uncertainty in the underlying model.

Ambient air pollution, urban green space and childhood overweight and obesity: a health impact assessment for Barcelona, Spain

Ambient air pollution, urban green space and childhood overweight and obesity: a health impact assessment for Barcelona, Spain

Characterization of organic materials in regulating soil carbon sequestration of urban greenspaces: Links to microbial necromass and community composition

Application of organic material is a win-win strategy that effectively boosts soil carbon (C) storage and promotes organic waste recycling in urban ecosystems. However, the divergent responses of C sequestration to organic materials and the underlying mechanisms remain unclear. Using molecular and litterbag methods, this study examined soil organic C (SOC) content, C sequestration efficiency of organic material (CSE-organic material), microbial necromass and community composition in urban greenspaces amended with different types of organic materials. The field experiment had seven treatments: addition of green waste (GreenWaste), green waste compost (GreenWasteCompost), biogas residue (BiogasResidue), biogas residue compost (BiogasResidueCompost), peat (PEAT), biochar (BioChar), and no organic material (Control). Organic materials after 16 months application increased SOC content by 34.1–87.0% compared with the Control and presented CSE-organic material in the order: BioChar > GreenWasteCompost > PEAT > BiogasResidueCompost > GreenWaste > BiogasResidue. Aromaticity index was positively correlated with CSE-organic material, indicating that aromatic C addition had a strong capacity to enhance C sequestration. Microbial necromass increased from 2.7 g C kg−1 in the Control to 3.9–5.0 g C kg−1 under organic materials addition. Bacterial necromass was enriched in the BiogasResidue and BiogasResidueCompost treatments, primarily because of sufficient substrate that facilitated the proliferation and activity of copiotrophic Firmicutes, whereas fungal necromass was 8.8–19.1% higher in the GreenWaste, GreenWasteCompost, and PEAT treatments than that in the BiogasResidue and BiogasResidueCompost treatments, accompanying by an increasing abundance of Ascomycota. However, the contribution of microbial necromass to the increased SOC was negatively correlated with CSE-organic material, suggesting that the input of recalcitrant C weakened the role of microbial necromass in C retention. Overall, this study reveals that the efficiency of organic materials application in promoting soil C accumulation depends largely on recalcitrant C rather than microbial necromass, which highlights the important role of organic waste acting as a C source in achieving urban sustainable development.

Local environment perceived in daily life and urban green and blue space visits: Uncovering key factors for different age groups to access ecosystem services

Inequality in access to green and blue spaces is a major issue in the field of environmental justice. Various factors significantly influence visitations to these spaces, including residential, commuting, and shopping areas. However, studies have mainly focused on residential environments. Analyzing the coupling of environmental and socioeconomic factors, including age, income, and childhood experience, and examining the direct and indirect effects of these factors for different age groups are needed to better understand the detailed context of inequalities in access to ecosystem services. We conducted a questionnaire survey and analysis to address these needs in an urban setting. The results demonstrate that several land use categories (i.e., agricultural lands in residential areas, grasslands near shopping areas, and deciduous forests near commuting destinations) positively correlated with visitation frequency, suggesting the lack thereof may be the cause of access inequalities. In particular, the perimeter per unit area of some land cover types, which shows the complexity of the form of each land cover category, was found to be a significant factor. We identified inequality in nature experience to be the key factor correlated with inequality in nature visits among the young age group. For the middle-aged and old age groups, nature-relatedness was positively correlated with visitation frequency. Proper design of the local environment, such as through land use planning, can be an effective measure for all age groups. For instance, long-bordered green areas in the Monsoon Asian region are an attractive traditional landscape, with high accessibility and a comfortable thermal environment. The key factors for each age group should be considered in spatial design and inclusive information-sharing to reduce inequality in access to ecosystem services.

Contribution of ruderal herbaceous vegetation to supporting services in Mediterranean urban greenspaces

Contribution of ruderal herbaceous vegetation to supporting services in Mediterranean urban greenspaces

A Systematic Review of the Impact of Changes to Urban Green Spaces on Health and Education Outcomes, and a Critique of Their Applicability to Inform Economic Evaluation

Several reviews have consolidated the evidence on the impact of living near an urban green space on improving health and education outcomes and reducing mortality. However, there is limited evidence on the effectiveness or cost-effectiveness of specific improvements to these urban green spaces, which would help decision-makers make informed decisions on how to invest in urban green spaces. Therefore, this review synthesizes the impact of more specific changes to, or investments in, urban green spaces on health and education outcomes, synthesizes the cost-effectiveness of these interventions, and critiques the applicability of the evidence for an economic evaluation. We find that interventions targeted towards improving play areas or fitness equipment tended to have mostly positive impacts on physical activity, while interventions on improving walking path, or the overall greenery showed a more mixed impact on physical activity. There were only two studies on the impact of changes to urban green spaces on mental health, with only one finding a positive association of the intervention with depression, and there were no studies measuring the impact of changes to urban green spaces and educational outcomes. From a cost-effectiveness perspective, we find that typically very small improvements are required to make the interventions a cost-effective policy choice; however, we found several limitations with using the existing evidence to estimate the cost-effectiveness of the intervention. Overall, we found that most of the evidence does suggest that improvements to urban green spaces can lead to improvements in physical activity, but further research is needed on the impact on mental health and educational outcomes. Furthermore, additional evidence with longer time horizons, multi-sectoral benefits, distributional outcomes, and more consistent outcome measures would assist in informing cost-effectiveness and may ultimately lead to improved decision-making around investments for urban green spaces in specific contexts.

EVALUATION OF PLANTS BASED ON ECOLOGICAL TOLERANCE CRITERIA: A CASE STUDY OF URBAN OPEN GREEN SPACES IN RIZE, TURKIYE

In addition to aggressive urbanization, climate change and ecological challenges also have serious negative effects on urban green areas. Moreover, the selection of inappropriate plants in urban green space landscape projects increases the severity of these negatives. Therefore, inappropriate plant selection is considered a significant threat to the sustainability of urban green spaces. This situation highlights the importance of selecting plants with high ecological tolerance in urban park landscape projects. In this study, all tree, shrub, and ground cover plants identified in 11 urban parks and open green areas in Rize province were evaluated in terms of ecological tolerance criteria (air pollution, drought, wind, temperature, cold, and salinity). A total of 223 plant taxa were examined (77 native, 3 semi-native, 143 exotic), and it was determined that 149 taxa (49 native, 100 exotic) were sensitive to at least one of these criteria, while the remaining 74 taxa (27 native, 47 exotic) had sufficient tolerance to all ecological variables examined. Prunus serrulata Lindl. ‘Kanzan’ was identified as the taxon with the weakest ecological tolerance, and the resilience statuses of the other taxa were presented in the assessment table created. As a result, it was found that there are taxa used in Rize urban open green areas that pose risks against ecological factors, and recommendations were made for future landscape planting projects.

Urban green spaces and public realm design in Cairo: Enhancing quality of life and environmental sustainability

The paper explores the pressing challenges and promising initiatives in enhancing urban green spaces and the public realm in Cairo, a metropolis grappling with rapid population growth and environmental degradation. As the city struggles with density, air pollution, and a shortage of green areas—far below the recommended standard for urban health—the article highlights key efforts to revitalize public spaces. Notable projects include the creation of large parks like Al-Azhar Park, the redevelopment of the Nile riverfront through projects such as Mamsha Ahl Misr, and the introduction of green infrastructure solutions like street trees, green roofs, and sustainable urban drainage systems. Despite these advancements, Cairo faces significant obstacles, including limited public land, budget constraints, and water scarcity. However, there are opportunities to address these challenges through innovative urban agriculture, public-private partnerships, and community participation in green space development. The paper suggests that through continued investment and thoughtful urban design, Cairo can foster a more sustainable, livable environment. By integrating green infrastructure into future development projects, the city holds potential to transform its landscape and improve the quality of life for its residents in the coming decades.

Contested Urban Green Spaces in India: Complex Dynamics of Environmental Development

This research paper examines the proliferation of urbanization in contemporary India has led to a pressing need for the preservation and expansion of green spaces within cities. As rapid development continues to reshape the landscape, the importance of green spaces in promoting ecological balance, enhancing public health, and fostering social well-being becomes increasingly evident. This paper presents a comprehensive analysis of the issues and challenges associated with green spaces in modern India.

Assessing pollinator richness on urban-grown mountain mint (Pycnanthemum spp.) populations

ABSTRACT Pollinators provide important ecosystem services in human-developed areas, including pollination for urban green spaces and agriculture. As developers aim to become more eco-friendly, understanding pollinator dynamics in these settings will help enhance pollinator services. Mountain mint plants (Pycnanthemum spp.; Lamiaceae) are commonly grown in urban green spaces and may provide resources to a large range of pollinators. There is a limited understanding, however, of the Pycnanthemum spp.–pollinator relationship. In this study, we used visual monitoring and DNA barcoding to evaluate flower visitor richness over the extended bloom duration of two native species of Pycnanthemum spp. in the greater Richmond area of Virginia (USA). We recorded a total of 85 taxa on Pycnanthemum muticum and 43 on Pycnanthemum tenuifolium flowers. In most cases, our visual monitoring results were confirmed or refined with DNA barcoding, enabling us to build a flower visitor barcode library for the region. The taxon assemblages varied between the two observed Pycnanthemum spp. in general, and over time, demonstrating that these plant species provide resources across taxa and are therefore good candidates for bolstering pollinators when developing urban green spaces.

Evaluating Policy Shifts on Perceived Greenspace Quality: Applying Regression Discontinuity During the COVID-19 Reopening Period

Abstract: Urban greenspaces have been essential in supporting residents’ well-being during the COVID-19 pandemic, particularly under strict lockdown measures. However, the impact of changing containment policies on residents’ perceived greenspace quality remains insufficiently explored. This study utilized online survey data collected between 11 October and 29 December 2022, in Shanghai, coinciding with the major policy shift on 5 December 2022. A probability proportionate to size sampling was adopted to survey residents aged 18 and above who had lived in the city for at least six months, yielding a total of 577 valid responses. We assessed residents’ perceived greenspace quality using 20 park- and community-level variables, focusing on both overall quality and specific features of greenspaces. A regression discontinuity design (RDD) was applied to evaluate how the lifting of the COVID-19 policies influenced residents’ perceptions of parks and community greenspaces. Our RDD estimation indicates no statistically significant change in residents’ overall perceived quality of parks after the policy shift, except for increased satisfaction with specific features such as plant diversity, maintenance, seating areas, trails, and large open spaces. In contrast, residents who responded after the policy shift reported a significantly higher perceived quality of community greenspaces compared to those who completed the survey before the shift (0.609 score difference, p < 0.01), with notable increases in satisfaction regarding plant diversity, maintenance, and seating areas. Perception of plant quantity remained unchanged in both types of greenspaces. Residents expressed greater satisfaction with sports facilities in parks, while community greenspaces were preferred for their water features and esthetic qualities. By adopting an RDD with a unique dataset, this study contributes empirical evidence to the current ongoing debate on the role of urban greenspace during the later stages of COVID-19. Specifically, it examines how changes in public health policy and the resulting increase in mobility might affect residents’ perceived greenspace quality. The findings can assist decision-makers and urban planners in developing more adaptive strategies to address the diverse needs of residents for greenspaces during the transitional period of a public health crisis.

Potential of Selected Species of Spiraea L. for Phytoremediation of Heavy Metals from Soils of Urban Areas

Four taxa of Spiraea were selected for this study: S. × cinerea Zabel ‘Grefsheim’, S. nipponica Maxim. ‘Snowmound’, S. splendens É. N. Baumann ex K. Koch and S. × vanhouttei (Briot) Carrière growing for a minimum of 5 years along heavily trafficked traffic routes. This study included the genus Spiraea due to its popularity in horticultural practice (commercial availability, widespread in urban environments). In addition, the use of ornamental shrubs for phytoremediation in urban green spaces effectively combines the aesthetic needs of residents with those of caring for the urban environment. This study was conducted in Poznań (population 550,000, the fifth largest city in Poland). Soils and foliage were examined in spring and autumn. Soil pH and specific electrolytic conductivity (EC) were determined. The content of micronutrients (Cu, Fe, Mn, Ni, Zn) and toxic heavy metals (Cd, Cr, Pb) in soil dry matter and leaves was determined. The uptake capacity of bioavailable forms of heavy metals by Spiraea from the soil was analyzed by determining the bioconcentration factor (BCF). It was found that the studied taxa meet the basic requirements for plants used for soil phytoremediation processes, especially for chromium phytoextraction. The degree of salinity of the tested soils did not pose a threat to the shrubs growing there, and most of the sites, despite the alkaline reaction, are suitable for their cultivation. S. × cinerea and S. × vanhouttei have BCFs for lead <1. The remaining taxa are characterized by strong concentrations of all analyzed elements. A particularly high BCF, above 10, was recorded for chromium and high for manganese and nickel.

Differences in Changes of Mobility Patterns Across the Globe—Evidence From a Natural Experiment

ABSTRACTThe impact of population mobility and transportation choices on the environment is significant. Sustainable mobility policies require an understanding of evolving mobility patterns. This study examines global mobility variations across countries using COVID‐19 Community Mobility Reports. Employing the k‐medoids algorithm and Dynamic Time Warping, we analyzed mobility dynamics. Results reveal diverse changes in population mobility. Around 52 Global North countries exhibit approximately 10% reduction in professional activity‐related traffic post‐COVID‐19. Regarding urban green space mobility, only 29 countries exhibit strong seasonality, with summer traffic in the northern hemisphere peaking at about 150% higher than winter traffic. Three groups of countries are identified concerning public transport mobility: returning to pre‐pandemic levels, experiencing a 25% increase, and nearly doubling from pre‐pandemic levels. This underscores the key determinants for sustainable mobility policy implementation. Fifteen highly developed countries share similar mobility patterns across six areas studied, facilitating the exchange of sustainable mobility solutions and best practices. This research underscores the importance of understanding and addressing evolving mobility patterns for effective environmental policy planning.

Socio-economic gradients in urban green space access and respiratory health

Abstract Background This study investigates social disparities as one of the drivers influencing the access to green spaces and exposure to natural environments, potentially exacerbating disparities in respiratory health in children. Methods Longitudinal ELSPAC birth cohort study data included 4384 complete case participants born in cities of Brno and Znojmo, examined throughout the years 1990-2010. Estimates on socio-economic status (SES) scores of children’s parents and their education were used as socio-economical predictors. Tree cover density (TCD) calculated as mean canopy closure percentage in the individual walking distance neighbourhoods and the ownership and accessibility of a garden were used as indicators of green space accessibility. Multiple logistic regression models were employed to estimate odds ratios for predictors of respiratory health outcomes, controlling for several confounders. Results Parents’ SES was found to be positively associated with neighbourhood TCD, and this effect was even more pronounced for garden owners. Higher tree cover was then significantly negatively associated with development of acute bronchitis (OR 0.88, CI 95 % 0.84-0.94 for 1 SD of tree cover), while not having a garden (OR 1.81, CI 95 % 1.42-2.33) and living in area with lower tree cover (OR continuously decreasing from 1.88 to 1.68 for lowest and highest quartile respectively) was significantly associated with progression of acute bronchitis into chronic bronchitis in a fully adjusted model. Vice versa, higher tree cover was statistically significantly positively associated with development of allergic rhinitis (OR 1.09, CI 95 % 1.03-1.15), suggesting viability of the novel method of estimation of individual neighbourhood greenness. Conclusions The results suggest protective effect of access to urban green spaces against adverse respiratory outcomes in children. The socially uneven distribution of access emphasizes the importance of urban policies in promoting urban health. #NGEU Key messages • There is a significant protective effect of access to green spaces against respiratory diseases and their progression. • There’s an unequal, but varied distribution of access to green spaces, and social gradient in health, highlighting the importance of urban green space distributive politics.