Urban Green Spaces Research Articles

From hard coal mining to a learning space for digitally supported participatory management of biodiversity

Purpose The purpose of this paper is to describe the conversion of the former coal mining site in Kamp-Lintfort into a public park and learning space for biodiversity. In 2020, an urban green space was established, featuring various aquatic and terrestrial habitats and a high level of biological diversity in the city centre with broad community support. Design/methodology/approach This study presents secondary data of a literature review on participatory management of biodiversity in urban green spaces, with a focus on the sustainability context, participation approaches, theoretical frameworks and the role of education. The example of Zechenpark Kamp-Lintfort (Germany) shows how urban green space development can meet the challenging demands of inner city development while fostering knowledge generation via citizen science and participatory biodiversity management. The study collected primary data on plant biodiversity using a citizen science approach to raise awareness and create opportunities for human–nature interaction. Findings Sustainable Development Goal (SDG) 11 is the most important development goal in the context of participatory biodiversity management of urban green spaces. Most of the studies have a place-based focus and integration of local knowledge is the main reason for a participatory approach. The findings show how a green learning space can offer opportunities for digital learning as well as participatory biodiversity management in urban areas. The project lead to an increase in local citizens’ awareness of biodiversity. Based on a literature review, this report identifies challenges and opportunities for establishing a green learning space for biodiversity education. The example illustrates that an urban green space can provide numerous possibilities for citizens and students to get involved and that it can foster the sustainable development of a new urban neighbourhood. Research limitations/implications A place-based approach limits generalisability. To overcome this limitation, a literature review was conducted, and the location was compared to two parks with similar site conversion history. Practical implications The example of developing an urban green space can inspire universities to take an active role in biodiversity management in urban green spaces, integrating biodiversity into university activities and creating a positive impact in the urban environment. Social implications Analysis of studies in the field shows that education deserves a more prominent role in theoretical frameworks. Originality/value The study represents an example of transition and citizen-led participatory management of biodiversity from a medium-sized city, transformation processes covering these aspects are underrepresented in literature.

Lived expertise of the structurally disadvantaged: towards a more just participatory transport planning process

In response to the negative effects of the car-dominated transport sector, especially in urban areas, and wider attempts to tackle the climate crisis, cities are reallocating car-dominated areas to promote active mobility, leisure and urban green space. These reallocations often take an experimental character and are accompanied by participation processes. Increased citizen participation results from both a paradigm shift in urban planning and a discourse shift towards mobility justice, emphasizing procedural and recognitional aspects of the transport transition. However, participatory planning processes themselves are conflict-ridden. They are criticised for favouring a loud, priviliged minority. Based on the need for diverse knowledge for mobility justice, including lived expertise, this study examines reasons for (non-) participation among structurally disadvantaged groups in transport planning, using Berlin’s Graefekiez neighbourhood as a case study. Focus groups were conducted with mobility-disabled people and women from a residential area with low socio-economic status. Our analysis revealed that non-participation was influenced by the feeling of being excluded and ignored. Simultaneously, the research format created was perceived as a welcoming space that better reflects the lived expertise of the neighbourhood and facilitates real exchange of perspectives. Based on this, recommendations are derived to improve participatory transport planning processes and the strengths of transdisciplinary projects.

Phytoremediation potential of potted plant species against vehicular emissions

Urbanization and industrialization are exponentially deteriorating air quality, ecosystems, and human health. Phytoremediation is cost cost-effective, sustainable, and nature-based solution against air pollution. This study is designed to evaluate four species, Chlorophytum comosum, Rhapis excelsa, Spathiphyllum wallisii, and Ficus benjamina for their phytoremediation potential. The experimental setup consisted of a sealed chamber to place potted plants and equipment, it was also connected to the vehicular exhaust pipe. The Air Pollution Tolerance Index was highest for F. benjamina (12.19) and lowest for Rhapis excels (8.58). C. comosum has the highest VOC removal efficiency (90%, 0.172 ppm h−1). NOx remediation was highest by F. benjamina with 0.057 ppm h−1 (77%) removal efficiency. SOx and CO were remediated more efficiently by C. comosum, as 89%, (0.18 ppm h−1) and 80% (0.23 ppm h−1), respectively. R. excelsa reduced a higher concentration of NH3 (77%, 0.06 ppm h−1) compared to other species. R. excelsa and S. wallisii may serve as bio-indicator species. These findings provide a sustainable, natural, economical, and eco-friendly way to mitigate air pollution. F. benjamina and C. comosum are suitable species for urban landscapes, green spaces, urban plantations, and green walls to curb air pollutants due to traffic and industries.

Planning eco-sensitive zones for promoting tree diversity and ecosystem services in urban academic landscapes: a case study from the North-western Indo-Gangetic plain

ABSTRACT Urban academic greenspaces provide a protective environment for the conservation of plants and animals and ecological health benefits to human beings. Several anthropogenic activities and landscape practices lead to patches of natural and built-up areas; therefore, a better understanding of campus tree diversity and ecosystem services among natural and built-up areas may help in biodiversity management. Considering this, we assessed how landscape heterogenicity (i.e. the proportion of natural and built-up/paved surface area) and planning principles influence tree density and diversity patterns in three zones (buffer zone: natural/remnant woodland; transition zone: mixed open grassland and woody plantation; core zone: paved/built-up, grassland, and scattered woody plantation) in the Indian Institute of Science Education and Research (IISER) Mohali campus (Punjab) India. We found a total of 1,993 trees belonging to sixty-eight species, mostly native flora. We found that landscape planning principles significantly influenced tree diversity patterns, with the highest tree diversity in the B3 buffer zone (H: 2.9, PIE: 0.9), which integrated elements of the original landscape and new plantations to optimise ecological value and the lowest diversity in the B2 buffer zone (i.e. H: 0.4; PIE: 0.2) with a monoculture plantation of exotic agroforestry species. We also observed that tree density was negatively influenced by impervious surface area (r = -0.68, p < 0.05) in the core zones and by the plantation of exotic species in the natural areas. The campus diversity supports birds of different feeding guilds (insectivore: 41%, omnivore: 25%, carnivore: 25%, frugivore/nectarivore: 13%, graminivore: 4%, and piscivore: 2%). Additionally, academic buildings planned with high canopy cover and density (45% and 95 ha−1) had reduced the wall temperatures of academic buildings from 12°C to 6°C compared to neighbouring buildings without tree cover. This highlighted the importance of maintaining tree diversity in urban academic institutions to promote urban sustainability.

Cultivar-dependent differences in plant bud microbiome and functional gene pathways in woody plants commonly used in urban green space.

Plant richness and microbiota have been associated with plant health; hardly any studies have investigated how plant taxa differs in microbiota in the context of human health. We investigated the microbial differences in buds of 83 woody plant taxa used in urban green spaces in hemiboreal climate, using 16S rRNA and whole metagenome shotgun sequencing. Bud microbial community was the richest in Cotoneaster Nanshan and C. integerrimus, and Malus domestica cultivars 'Sandra' and 'Lobo' and poorest in Ribes glandulosum. Metagenomic shotgun sequencing of two M. domestica and four Ribes varieties confirmed differences in taxa in bud microbiota and indicated higher siderophore synthesis in Malus. Microbial richness, including bacteria, archaea and viruses, and functional richness of gene pathways was higher in Malus compared to Ribes. The ten most abundant amplicon sequence units, often referred as species, belonged to the phylum Proteobacteria. The differences between plant taxa were evident in classes Alpha- and Gammaproteobacteria, known for potential human health-benefits. Since environmental microbiota contributes to human microbiota and immunoregulation, horticultural cultivars hosting rich microbiota may have human health benefits. Further studies are needed to confirm the effectiveness of microbially-oriented plant selection in optimizing human microbiota and planetary health.

Assessing Appropriation of Space in Urban Green Spaces: Three Case Studies in Downtown Shanghai

This study investigated patterns of activities in urban green spaces (UGSs) in downtown Shanghai. UGSs are essential public infrastructure, contributing to urban sustainability, quality of life, and social cohesion. Although widely studied, there is a gap in the literature regarding Chinese UGSs when the object of study is the nature the activities. In this sense, we aimed to investigate the activities from the perspective of appropriation of the space, considered here as different from the use of space. This study addressed this by analyzing user demographics, frequency, and spatial activity patterns to assess how these activities could be classified and scored according to a varying levels of appropriation. Through a mixed-methods design based on non-participant observation and behavior mapping, the study was conducted across three comprehensive parks in Shanghai, divided into nine observation zones. The data were analyzed through descriptive statistics, IBM SPSS, and qualitative coding, revealing, as the main findings, sixty distinct activity types, a soft to moderate level of appropriation, and notable variations in demographic presence and temporal trends. This research underscores the effectiveness of observational methods, validates appropriation as an analytical category, and emphasizes the importance of structured classification systems for improving the understanding of UGSs’ socio-spatial performance and their societal role.

Regulation of humid heat by urban green space across a climate wetness gradient

Regulation of humid heat by urban green space across a climate wetness gradient

Characteristics of soil organic carbon fractions and influencing factors in different understory mosses in karst urban parks.

The impact of different vegetation types on soil organic carbon (SOC) is a key focus in global warming research. Bryophytes, commonly found in karst urban forests, significantly contribute to carbon accumulation in surface soil. However, the changes in soil organic carbon fractions under moss and the influencing factors remain unclear. To address this knowledge gap, the study examined the organic carbon content, soil physicochemical properties, and associated environmental factors in both moss-covered soil and bare soil under six different forest species within an urban park. The results showed that the SOC contents under moss cover in evergreen coniferous forest (127.28g/kg), bamboo forest (144.70g/kg), deciduous broad-leaved forest (87.63g/kg), and evergreen shrub (109.28g/kg) were significantly higher compared to bare soil. Moss cover also had a significant impact on soil readily oxidizable carbon (ROC), particulate organic carbon (POC), mineral-associated organic carbon (MOC), and heavy fraction organic carbon (HFOC) (P < 0.01). The soil under moss had a higher content of stable organic carbon fraction, which is conducive to the stability of the soil organic carbon pool. The interaction between moss cover and stand type had the most significant effect on soil organic carbon, especially in bamboo forests. Canopy density, moss biomass, and soil moisture were the main environmental factors affecting the content of soil organic carbon and its fractions, while soil organic carbon content was mainly affected by soil nitrogen and phosphorus. This study establishes a theoretical framework for investigating the carbon cycle in karst urban underforest ecosystems, offering a scientific basis for the management and preservation of urban green space ecosystems. Future studies should include bryophytes in the assessment of dynamic factors affecting the soil carbon pool under forest cover and further explore the function and ecological significance of bryophytes in understory ecosystems.

Exploring the Complex Association Between Urban Built Environment, Sociodemographic Characteristics and Crime: Evidence from Washington, D.C.

The urban built environment and sociodemographic characteristics have complex relationships with urban crime. However, previous studies have had limitations such as generalizing urban green space types, urban functionality, and sociodemographic characteristics. Given these, this study aimed to explore the relationship between them using more detailed indicators. The study utilized Google Street View and points of interest to depict the built environment. Building on previous work that segmented natural and artificial elements in streetscape images, this study further distinguished trees, bush, and grass. Additionally, it incorporated data from the Data Analysis and Visualization Unit of the DC Office of Planning to reflect a broader range of individual characteristics. Weighted least squares regression and Pearson correlation analysis were used to test the relationship between the built environment, sociodemographic, and crime, respectively. Some of the key findings are as follows. (1) Trees, bushes, and grass all reduce crime. (2) Urban functionality is hard to curb crime by enhancing informal public surveillance. (3) Among the sociodemographic variables, the walking commute rate is the variable most strongly positively correlated with crime. (4) Family relationships play an important role in suppressing crime. This study examined a more comprehensive range of indicators affecting urban crime in favor of safer cities.

Pathogens of Plant Diseases in Osh City and Their Connection with Climatic Conditions of Kyrgyzstan

The article discusses the issues of improving the environmental situation, creating a favorable environment for health and, therefore, the need to combat plant pathology in large cities of Kyrgyzstan. Methods of increasing sustainability are analyzed and recommendations for improving the efficiency of the urban green space system are proposed. Based on this, the purpose of the work is to study the possibilities of improving the ecological condition of cities in modern conditions by controlling pests of urban plants. During the research, methods of qualitative identification and analysis of pests of urban plants were used. The information and empirical base of the study was our own laboratory research data. The scientific novelty lies in the identification and identification of pests of planted woody, shrubby and ornamental plants in Osh city. Based on the analysis of pests of planted woody, shrubby and ornamental plants in the city of Osh, it is proposed to strengthen control and research in the field of phytopathology to improve the urban environment by greening urban areas with resistant species to the identified pathologies of woody, shrubby and ornamental plant species. The necessity of forming a pest control system for plants and protecting the ecology of cities is substantiated. As a result of the study, the main types of pests of planted woody, shrubby and ornamental plants in urban areas of Osh were identified.

Thermal Comfort and Green Spaces: The Role of Temperature-Regulating Elements in Neighborhood Parks

According to current studies, the thermal effects of global warming will affect urban areas more intensely. In the face of this situation, strategies for the improvement and management of urban green spaces are becoming increasingly important in sustainable landscape design. These strategies promote social sustainability by positively affecting individuals’ physical and psychological well-being, taking into consideration ecological sustainability. Projections regarding global warming emphasize that the density of hardscapes and green spaces, the selection of plant species, and the distribution of plants considered within the scope of this study should be taken into account. This research was conducted in the Görükle neighborhood of Bursa, focusing on the role of temperature-regulating elements in 14 neighborhood parks. Systematic temperature measurements were carried out in the research area on the 10th, 20th, and 30th of July and August, specifically between 12:00 and 13:00, during peak temperature hours. The presence of parks that are close to each other and relatively far away from each other in the study area was seen as advantageous to filter the effects of plant differences in similar conditions. Furthermore, evaluating these various factors together highlights the multifaceted nature of thermal comfort. Designated temperature measurement points included three points (hard surfaces and hard surfaces surrounded by vegetation and planted green spaces) in each park. An analysis utilizing SPSS and the RayMan program revealed that parks with a softscape to hardscape ratio of approximately two to one experienced temperature reductions of 2.5 to 3 °C. Furthermore, the findings indicate that coniferous trees have a more significant impact on thermal comfort compared to deciduous trees. The significant differences identified in this study underscore essential considerations for urban design processes aimed at achieving sustainability.

A blue–green ratio of urban wetlands as an ecosystem health indicator: the case of urban sprawl in Nagpur, India

ABSTRACT Rampant urban sprawl has affected the structure and function of existing urban green and blue spaces, exposing developing cities to unexpected disaster events. Drawing on a mixture of secondary information supported by GIS and field-based studies, we assessed the impact of growing impervious surfaces on the dynamic zones of urban wetlands in Nagpur, India. We compared decadal data (2000-2020) to understand the pattern of wetland loss and its drivers in the region. Our findings reveal a significant loss of wetland structure and area over the past two decades, raising alarming concerns regarding ecological and economic repercussions. To address these issues, we propose a blue–green buffer-based assessment approach that incorporates local knowledge and observations along with proactive monitoring of ecosystem health. Our study highlights the urgency of reducing the spatial complexity of landscape patches, restoring wetland buffers, declaring wetland buffers as no-go zones, and promoting corridor connectivity to urban wetlands to improve urban blue infrastructure health. Multi-sectoral and stakeholder cooperation, involvement, and strict enforcement of the Wetland Rules (2017) by local governing bodies can help build urban resilience by protecting urban blue–green infrastructure.

Computer-aided analysis: Correlation between urban green spaces and crime rates

Abstract. Urban green spaces have been associated with various social and environmental benefits, including their potential impact on crime rates. This study investigates the correlation between urban green spaces and crime rates using a combination of Geographic Information Systems (GIS) and advanced statistical analysis. By analyzing data from a large metropolitan area, we examine how green space characteristics such as size, type, and maintenance influence crime patterns. Our findings indicate that well-maintained green spaces with diverse amenities can significantly reduce crime rates, whereas neglected areas may become hotspots for criminal activities. The study also explores temporal patterns of crime in relation to green spaces, revealing that adequate lighting and community presence are crucial for nighttime safety. Policy recommendations are provided to help urban planners and policymakers leverage green spaces to enhance urban safety. By integrating multiple analytical techniques, this research contributes to a comprehensive understanding of the role of green spaces in urban crime prevention and offers actionable insights for future urban planning.

Assessment and Dynamic Prediction of Green Space Ecological Service Value in Guangzhou City, China

As an important part of the urban ecosystem, urban green space provides a variety of ecosystem services, including climate regulation, soil conservation, carbon sink and oxygen release, and biodiversity protection. However, existing remote sensing evaluation methods for ecological service value lack the evaluation indicators of ecosystem service value for Guangzhou, China, and the evaluation method depends on the land cover type. Based on remote sensing technology and random forest algorithm, this study addresses these gaps by integrating remote sensing technology with a random forest algorithm to enhance the accuracy and rationality of ESV assessments. Focusing on Guangzhou, China, we improved the ecological service value evaluation system and conducted dynamic predictions based on land-use change scenarios. Our results indicate that the total ESV of Guangzhou’s green space was USD 7.323 billion in 2020, with a projected decline to USD 6.496 billion by 2030, representing a 12.37% reduction due to urbanization-driven land-use changes. This research highlights the noticeable role of green spaces in urban sustainability and provides robust, data-driven insights for policymakers to design more effective green space protection and management strategies. The improved assessment framework offers a novel approach for accurately quantifying urban ecosystem services and predicting future trends.

How do urban green space attributes affect visitation and satisfaction? An empirical study based on multisource data

Urban green spaces (UGSs) are major settings of human–nature interaction and important to public well-being. Visitation and satisfaction are indicators that reflect the utilization degree of and feedback regarding UGSs. The focus of this study is to analyze the visitation and satisfaction characteristics of different types of UGSs, analyze the dominant factors affecting these indicators, and rank their importance to provide strategies for improving management. Here, 50 typical UGSs in Shanghai are selected. All-subset regression, hierarchical partitioning analysis and other methods are comprehensively used to explore the influencing factors. The results are as follows: 1) Comprehensive parks have the highest visitation rates, whereas community parks have the lowest visitation rates but the highest satisfaction rates. 2) UGS size has the greatest influence on visitation, followed by connectivity, building shape index, and edge density, with contributions of 69.35 %, 16.40 %, 8.50 %, and 5.75 %, respectively. 3) Transportation facility density and edge density have the greatest influences on satisfaction, with contributions of 51.49 % and 48.51 %, respectively. In this study, the applicability of using multisource data to analyze UGS attributes and their factors affecting visitation and satisfaction are demonstrated. Targeted strategies for constructing UGSs will help authorities plan and manage UGSs effectively.

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

BackgroundThe burden of childhood overweight and obesity attributable to ambient air pollution and a lack of urban green spaces (UGS) remains unknown. This study aimed to estimate the attributable cases of childhood overweight and obesity due to air pollution and insufficient UGS exposure in Barcelona, Spain. MethodsWe applied a quantitative health impact assessment approach. We collected childhood overweight and obesity prevalence levels and exposure data from 69 spatial basic health zones in Barcelona. We estimated particulate matter (PM2.5) and nitrogen dioxide (NO2) levels using land use regression models, normalized difference vegetation index (NDVI) levels using remote sensing and percentage of green area (%GA) using land use. We estimated relative risks, population attributable fractions, and preventable overweight/obesity cases in children under following scenarios: Compliance of World Health Organization (WHO) air quality guidelines (AQGs) for (1) PM2.5 and (2) NO2; achieving (3) city-target NDVI levels and (4) 25% green area (%GA) recommendations. The analyses were stratified by socioeconomic deprivation index (in quintiles). Uncertainty was quantified using Monte Carlos simulations. ResultsCompliance of WHO AQGs could prevent 0.4% [253 (95%CI, −604; 1086)] and 4.2% [3000 (95%CI, 1009; 4943)] of childhood overweight/obesity cases due to excess PM2.5 and NO2 levels in Barcelona, respectively. Compliance of NDVI and %GA targeted levels could prevent 6% [4094 (95%CI, 1698; 6379)] and 10% [6853 (95%CI, 1440; 12779)] of childhood overweight/obesity cases respectively. The preventable burdens of childhood overweight/obesity cases were slightly higher in middle-class socioeconomic areas due to the higher adverse exposure levels at baseline (high air pollution, less UGS). DiscussionCompliance with WHO AQGs and achieving UGS targets can reduce childhood overweight and obesity levels in Barcelona, and potentially in other locations as well. This underscores the need for policies that foster healthier urban environments of high environmental quality in order to protect child health.

Assessing indicators and preferences of cultural ecosystem services in urban areas: a case study of Murcia, Spain

ContextThe degradation of the environment due to anthropogenic action underscores the need to demonstrate the benefits that natural areas provide to society. Continuously growing urbanisation trends and high demand on urban green infrastructure requires the inclusion of cultural ecosystem services (CESs) in strategic urban planning. To achieve this, understanding the population's preferences regarding the various CESs provided by urban green spaces is extremely useful for their management and long-term planning strategies. Nevertheless, the complexity of urban environment and urban CESs and inclusion of participatory-oriented and demand-based planning poses challenges in conducting solution-oriented assessments.ObjectivesTo address this issue, we aim to define and validate spatial indicators that are applicable in any urban area. We employ them to quantify the provision of CESs considering that such approach can contribute to better urban planning strategies.MethodsA survey, aiming to validate five proposed CESs indicators and evaluate the population’s perception regarding the importance of CESs in urban green areas in the city of Murcia (Spain) was conducted. In total, 733 answers were collected. The survey results underwent through statistical and geospatial analysis at the neighbourhood level, which facilitated the creation of CESs maps, considering socio-demographic characteristics of the respondents.ResultsAll five proposed CESs indicators were highly accepted by the respondents across all demographic groups. Conversely, differences in the perception of importance of CESs are noted based on the age of the respondents. Disparities in CESs provision are observed between different city neighbourhoods and socio-demographic groups.ConclusionsWe identified significant differences in CESs perception by age group. We also detected the areas where action is needed to improve the CESs provision. Through this study, we emphasize the significance of participatory-based, demand-oriented, and territorially tailored planning approaches to ensure the high provision of CESs and enhance urban well-being.

Potential drivers of urban green space availability in Latin American cities

AbstractUrban green spaces play a critical role in regulating air temperature, reducing air pollution and enhancing people’s well being. Yet, existing data and research on potential drivers of urban green space availability in Latin America are limited. Here, focusing on 371 large cities in 11 countries in Latin America, we described the total and per capita variability of urban green space, its spatial configuration and green urban parks across the categories of cities’ natural, built and socioeconomic environments. We tested the relative importance of geographic (climate) versus city-level built environment (population, population density, street intersection density) and socioeconomic (city gross domestic product per capita, unemployment, education) drivers in explaining urban green space availability. We found a high level of heterogeneity in green space quantity across cities and across categories of cities’ environments. Relative to other city factors, climate zone had the largest influence in explaining the quantity of green space, whereas education, street intersection density and population density were the most important drivers of urban park availability. The significance of climate for green space availability, combined with the inequitable quantity of green space, indicates that cities have differing capacities to implement nature-based solutions for heat mitigation and health promotion.

Assessing Buffer Gradient Synergies: Comparing Objective and Subjective Evaluations of Urban Park Ecosystem Services in Century Park, Shanghai

Urban parks provide essential ecosystem services (ESs) that enhance human wellbeing. However, discrepancies often arise between objective assessments of these services and stakeholders’ subjective perceptions. This study addresses a research gap concerning the synergies and tradeoffs between objective evaluations and subjective perceptions of key ecosystem services across various spatial scales. We investigated six key ecosystem services in Century Park, Shanghai, across seven buffer radii (8–100 m). Objective data were obtained from park view images (PVIs) and spatial analysis, while subjective perceptions were gathered through a scoring survey of 33 stakeholders. The key finding is that a buffer radius of 35 m offers optimal synergy between objective and subjective assessments for most ESs, particularly in pollution mediation, temperature regulation, and cultural services. Professionals showed stronger alignment in regulatory services like pollution mediation and temperature regulation, while residents exhibited higher synergy in net primary production (NPP) beyond a 75 m radius. Notably, cultural services displayed nuanced differences, with professionals preferring simpler landscapes and residents demonstrating varied aesthetic preferences. These findings emphasize the importance of integrating objective data and human perceptions in urban green space planning and governance. By incorporating diverse stakeholders and identifying optimal buffer zones, planners and designers can effectively balance ESs with human experiences. This approach ultimately fosters more sustainable and wellbeing-centered urban environments.

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.