The influence of small green space type and structure at the street level on urban heat island mitigation

The purpose of this study was to determine the types and structures of small green spaces (SGs) that effectively reduce air temperature in urban blocks. Six highly developed blocks in Seoul, South Korea served as the research sites for this study. Air temperature was measured at the street level with mobile loggers on clear summer days from August to September in 2012. The measurements were repeated three times a day for three days. By analyzing the spatial characteristics, SGs within the six blocks were categorized into the four major types: polygonal, linear, single, and mixed. The result revealed that the polygonal and mixed types of SGs showed simple linear regression at a significant level (p < 0.01). It indicated that the blocks’ urban heat island (UHI) mitigation (ΔT_Rmn) increased in a linear fashion when the area and volume of these two types of green spaces increased. The area and volume of a polygonal SG with mixed vegetation, over 300 m² and 2300 m³, respectively, lowered the ΔT_Rmn by 1 °C; SG with an area and volume of larger than 650 m² and 5000 m³, respectively, lowered the ΔT_Rmn by 2 °C. The results of this study will be useful to urban planners and designers for determine the types and structures of urban green spaces to optimize the cooling effect, as well as how such green spaces should be designed and distributed.     

Influence of green spaces on environmental satisfaction and physiological status of urban residents

Influence of urban green spaces on human was evaluated with subjective questionnaires as well as physiological measurements. Five sample plots vary in color, size and scent of major plants and one no-vegetation area located in Shanghai Botanical Garden, China were chosen. 249 questionnaires on subjective satisfaction evaluation were collected; in addition to 64 visitors took the measurement of physiological parameters like Electroencephalogram (EEG) and Electrocardiogram (ECG). Questionnaire results show that color is one of the most important factors which affect the overall satisfaction of people with their vegetation environment. The way how people perceive vegetation environment was probed by PCA analysis. Age difference analysis show children and elder people presented higher satisfaction with vegetation environment than adults. Significant negative correlation between the ratio of low-frequency to high-frequency (LF/HF) values in heart rate variability (HRV) analysis and satisfaction values indicated HRV may be an effective parameter for green spaces influence evaluation.     

Assessing the influence of location attributes on urban forest species composition in suburban neighbourhoods

Determining how suburbanization shapes tree-species composition and diversity is vital in Canadian and most nations’ cities, as suburban and peri-urban areas continue to grow faster than any other region. These areas, characterized by various land types and uses, represent differences in management and governance, jurisdiction, planting practices and species selection, and professional and political agendas. Such complexities emphasize the importance of exploring the influence of various environmental and location attributes of suburban neighbourhoods. Using hierarchical cluster analysis to classify urban forest species assemblages, we found that location attributes such as land type, development decade, and geography are influential on species composition and diversity − but only to an extent. We found that street-tree assemblages were classified more distinctly than remnant woodlands, which were in turn more distinct than tree communities found on residential properties. Residential land types had a high degree of species heterogeneity, highlighting the importance of not only considering the location attributes chosen for this study, but also including socioeconomic and cultural variables in future ecological classification schemes. Identifying drivers of species composition and diversity is useful for developing and implementing forest management strategies for urban and peri-urban areas, as different species assemblages give rise to different challenges and management opportunities, as well as varying quantities of ecosystem services, values, and benefits.     

南宁城市街旁绿地区域性景观探讨

城市街旁绿地是城市居民利用最为广泛的绿地之一,是城市园林形象的直接表现。南宁是一座无论在自然环境条件还是地方文化底蕴方面都极具特色的城市。为了创造出更宜人的城市街旁绿地空间,需要在园林设计中充分重视景观地域性。景观地域性的表达本质上也是对南宁地方文化的继承与发扬。     

The relationship between urban green space and social health of individuals: A scoping review

Urban green space is an important resource to effectively improve the urban environment and human health. A growing body of evidence highlights their positive impact on physical, mental and social health. Less focus has been paid to the social health benefits of urban green space. Designing urban green space to improve the social health of various groups has become a crucial problem, given the lack of uniformity in defining and measuring social health, as well as the varying social health needs of different individuals. This review aims to explore the relationship between urban green space and social health of individuals, which is defined as how one gets along with other people, how other people react to him/her, and how one reacts with the social institutions and societal mores. According to the PRISMA extension for Scoping Review (PRISMA-ScR) guidelines, 60 articles published between 1998 and 2022 met the inclusion criteria were reviewed. The results demonstrated that different types of urban green space significantly influenced the social health of individuals. The dimensions of social health of individuals based on urban green space could be divided into four groups: social contacts, social relations, social support and social connections, which were mainly affected by the physical characteristics, perceptions, and usages of urban green space to varying degrees. Socio-demographic characteristics could moderate the strength and orientation of the relationship between urban green space and social health of individuals. As the first scoping review to analyze the relationship between urban green space and individual social health, this study not only provides evidence for the social health benefits of urban green space, but also offers information and tools for future research and policymakers.     

The effects of naturalness,gender, and age on how urban green space is perceived and used

Neighbourhood green space serves an important function for the urban population, and provides valuable ecosystem services for human well-being. In this article, we investigate the effects of naturalness, gender, and age on the activities, aesthetics, and self-reported well-being associated with urban green space. Our findings are based on a postal survey of residents living in close proximity to six different green spaces in the city of Gothenburg, Sweden. It is shown that higher perceived naturalness generated more activities and higher aesthetic values and self-reported well-being for residents living close to urban green spaces. The results also indicated that, regardless of the type of naturalness, women were more active in urban green spaces than were men. Women also saw greater aesthetic value in green spaces than men did, and had higher self-reported well-being associated with the urban green spaces. Finally, older residents were shown to participate in a greater number of nature-related activities than younger residents. Older residents also saw greater aesthetic values and had higher self-reported well-being associated with urban green spaces than younger people did. Seemingly, this poses a considerable planning challenge if areas of perceived naturalness are to be retained in cities, since the present trend is for reduced green spaces in cities and a ‘parkification’ of surviving natural areas. Further, because of the importance of perceived natural areas to the elderly, and in particularly women, distances to urban green areas should not be too great.     

The influence of subjective perceptions on the valuation of green spaces in Japanese urban areas

This study focuses on the importance of subjective perceptions in the valuation and conservation of urban green spaces. Because physical attributes of the natural environment are filtered through individuals’ perceptions, their self-reporting of the extent of green spaces fluctuates according to their biases. However, the determinant of people’s self-reporting of the extent of green spaces within neighborhoods remains unclear. An examination of the relationship between the physical attributes of green spaces and the self-reported extent of green spaces is required to address this uncertainty. Accordingly, two separate studies were conducted by establishing two types of data on green spaces: physical data derived from a Geographical Information System and questionnaire-derived self-reported data. Multiple regression analysis was performed to compare the effects of different types of physical green spaces on the self-reported extent of green spaces. The results indicated that residents’ perceptions of same-sized green spaces differed considerably depending on their type. To ascertain the effects of subjective perceptions on economic valuation, a life satisfaction approach was subsequently applied within two separate analyses. In the first analysis, reflecting a normal pattern, the relationship between life satisfaction and the area of green space was examined, and in the second analysis, the self-reported extent of green spaces was used as an intermediate variable between green spaces and life satisfaction. A comparison of the estimated values from the two analyses revealed significant differences, depending on whether self-reported green spaces were used as an intermediate variable. Specifically, values of urban green spaces fluctuated more than those of forests in the case of self-reported green spaces. Although urban planners and experts generally emphasize the physical attributes of green spaces, such as area, these results indicate that it is critical to consider people’s perceptions.     

榆林市城市绿地景观植物与配置设计

通过对榆林市绿地景观中常用植物资源的分析,探讨了城市绿地植物配置设计原则,应根据植物的生物学特性科学地、有机地、合理地搭配应用,以期优化榆林市绿地景观植物与配置设计。     

Mapping research priorities for green and public urban space in the UK

Research mapping is a method of organising research information as part of a process of formulating a research policy in a specific area. A research mapping project was undertaken in the UK, which aimed to map existing and future research into public and green space, to identify gaps in order to help set priorities for future research, and to develop a freely accessible and searchable database of this research. The mapping was structured around two axes. The first axis was of research themes based on The Value of Public Space but developed further and broken down into sub-themes. The second axis was a typology of green and public space based around Planning and Policy Guidance Note 17 (PPG17) with elaboration from Green Spaces, Better Places. Research dating back to 10 years was collected together with information on recently completed, ongoing and planned UK research. Only research meeting specific quality criteria was included. Some information was also collected at a seminar where attendees from a range of organisations were invited to offer their perspectives on where research priorities should be directed. All the material was analysed and the main trends were identified. Three key cross-cutting themes common to much of the research were identified. These are the general lack of baseline surveys against which to assess progress over time; methodological issues, especially the need to standardise data collection methods and techniques; the classification of social groups, currently considered to be too crude.It was found that most research has been undertaken on physical aspects, such as planning and on biodiversity. Economic values have also been a focus, but on a smaller scale. Social research is quite well covered but very patchy. Management is better covered than maintenance. By far the weakest area represented in the research is health and well-being, both in terms of social groups and types of green space. Priorities for further research were then identified.     

Assessment of green space benefits and burdens for urban health with spatial modeling

We present a new spatial model to quantify and map health-related impacts of urban green space (UGS), with the aim to address major shortcomings of existing models and to meet the needs of urban spatial planners for quantitative, spatially-explicit assessment of both the health benefits and burdens of UGS. This GIS-based model uses publicly available high-resolution geospatial data to estimate street-level values of five major determinants of urban health that are significantly influenced by urban spatial design (including UGS): unattractive views, heat stress, air pollution, perceived unsafety and tick-bite risk. We also describe a potential major application of the model for urban spatial planners, a so-called hotspot analysis for a set of five urban design-related health problems, which can assist in setting spatial priorities in urban greening strategies as well as in designing effective greenspace interventions. Hotspots are areas within a city where urban design-related health problems are the largest. An analysis for Maastricht (The Netherlands) showed that in hotspots UGS was mostly a net burden, but also that redesign of UGS could make its role more beneficial for human health.     

Amenity trees and green space structure in urban settlements of Kigali,Rwanda

According to the national policy, overall forest and agroforestry cover in Rwanda is to increase up to 30% land cover by 2020. On the other hand, demographic data reveal that Rwanda's urban areas are among the fastest-growing on the continent. Unfortunately, there is only little information of the effects of such a rapid urbanization on tree cover and green space structure, knowing that data on urban plant assemblages in the country are rather rare. The paper discusses developments in Kigali's green spaces with regard to its rapid rate of expansion. An integrated approach of research, combining results from interview sessions, desk-based investigations, walk-over and vegetation surveys, and photogrammetric analyses of remotely acquired imagery was applied. The findings suggest that the city green space network consists of plant assemblages largely dominated by alien species (75%). Tree cover fraction averaged at around 10–35%. No significant difference was observed between field-drawn and photogrammetric-based fraction of tree cover estimates; making the later a quick but cheap tool for rapid tree cover evaluation. Cultivated forests, urban woodlots and domestic garden tree stands are far the most dominant types of green spaces in terms of coverage of city surface area. Street tree communities and institutional gardens appear to be the most intensively designed green space layouts. Both distribution and species composition in domestic gardens were socioeconomic-driven. For instance, palm trees were characteristic of fortunate quarters while fruitbearing ornamental such as Psidium guajava and Persea americana were common within scattered and informal settlements. Markhamia lutea, Erythina abyssinica, Euphorbia candelabrum, Phoenix reclinata and Acacia sieberiana are among native taxa that thrive to keep a place in the city. Euphorbia tirucalli, a native tree that is widespread in home compound fences within informal settlements, is significantly declining as modern housing expands and concrete-based fences replace live enclosures.     

Subjective perception of noise exposure in relation to urban green space availability

Noise pollution has been recognized as one of major threats to the health of urban residents. Increasing green space availability can create a natural buffer to the adverse effects of living in an urban environment. These positive effects of urban green space can be directly related to an objective reduction of noise levels and – indirectly – to the subjective perception of noise exposure. In our study carried out in Lodz, Poland, we explored the relationship between objective noise levels and the subjective perception of noise exposure by urban residents in relation to urban green space availability. We refer to objective noise exposure expressed as GIS modelled L_den derived from noise maps (compliant with the Environmental Noise Directive, 2002/49/EC), and subjective (self-reported) perception of noise exposure as declared in a questionnaire-based survey. We compared the percentage of green space in a buffer, the objectively measured noise level, and the perceived exposure to noise to find the most appropriate radius of the green space buffer. We decided to choose the green space coverage which is not correlated with an objective noise level to avoid potential multicollinearity in regression models. This contrasts with most studies, in which the radius of the buffer is set a priori. We thus compared the selected buffer of green space coverage – 300 m (representing green space availability) – with perceived noise exposure. We used the spatial error probit model to differentiate the impacts of objective and subjective noise indicators, at the same time including also the factor of green space availability. We found out that the direct effect of objectively measured noise levels, education, the presence of noisy neighbours, and building characteristics were the most important variables influencing the self-reported perception of noise by urban residents. The indirect effect of green space availability on noise perception was not strong, yet statistically significant. Although our study does not provide clear-cut evidence, it indicates that the indirect, psychological effects of urban green spaces can positively affect the life satisfaction of urban residents.     

Static home-based versus dynamic mobility-based assessments of exposure to urban green space

There is growing interest in urban green space exposure estimated dynamically by accounting for individuals’ mobility during daily life. We aimed to explore if daily green space exposure estimates based on individuals’ mobility substantially differ from static home-based exposure estimates, and to examine potential effect modification by personal (sex and work status) and temporal (weekends versus weekdays) characteristics. To assess the association between daily exposure to urban green space, we used home address and time-activity data collected from 1911 participants in western New York, US, using their GPS-enabled mobile phones. We abstracted both individuals’ home address based (home-based) and daily time activity based (mobility-based) green space exposures from the Normalized Difference Vegetation Index (NDVI). Then, we assessed the association between mobility-based and home-based exposure estimates using linear mixed effect regression models with subject-specific random effects. We also explored whether this effect was modified by individual-level characteristics, including work status and sex, as well as whether assessments took place on weekdays versus weekends. We found that daily dynamic exposure to urban green space based on individuals’ mobility was not substantially different from static exposure estimates based on one’s residence, but that there were statistically significant effect modifiers. Specifically, the correspondence between mobility-based and home-based exposure to green space was relatively lower for employed compared to unemployed participants, whereas their correspondence during weekends increased compared to weekdays. Our findings suggest that there is a strong correspondence between mobility-based and home-based exposure to urban green space, but that their associations are modified by personal and temporal characteristics. Further research is needed to confirm our finding for general population in other settings, such as different seasons and other regions.     

Patterns of human behaviour in public urban green spaces: On the influence of users' profiles,surrounding environment,and space design

Public urban green spaces (PUGS) play a vital role in the dense urban fabric as places of Nature-Society contact and socialization. Despite some advances in the field, the relationship between the PUGS surroundings and their users' behaviours remains unclear. This study examined the patterns of human behaviour in four PUGS of the city of Porto, on the north Portuguese coast, where the behavioural mapping method was applied. Observational data regarding 979 PUGS users' socio-demographics and behaviours were recorded on a base map and a grid between August and November 2020. The use patterns during different times of the day were disaggregated across behaviours and users' profiles, and their relationship with the surroundings and design elements was assessed with ANOVA, Chi-Square test, and Pearson correlation. The findings presented may pave the way for future studies and inform the urban planning and design of the effectiveness of new interventions, namely providing more accurate aligning between the greenspace design language with users' needs. Furthermore, this study highlights the importance of considering the sociodemographic background of PUGS users and the surroundings to guide designers and planners.     

Challenges of urban green space management in the face of using inadequate data

Effective urban planning, and urban green space management in particular, require proper data on urban green spaces. The potential of urban green spaces to provide benefits to urban inhabitants (ecosystem services) depends on whether they are managed as a comprehensive system of urban green infrastructure, or as isolated islands falling under the responsibility of different stakeholders. Meanwhile, different urban green space datasets are based on different definitions, data sources, sampling techniques, time periods and scales, which poses important challenges to urban green infrastructure planning, management and research. Using the case study of Lodz, the third largest city in Poland, and an additional analysis of 17 other Polish cities, we compare data from five publicly available sources: 1) public statistics, 2) the national land surveying agency, 3) satellite imagery (Landsat data), 4) the Urban Atlas, 5) the Open Street Map. The results reveal large differences in the total amount of urban green spaces in the cities as depicted in different datasets. In Lodz, the narrowly interpreted public statistics data, which are aspatial, suggest that green spaces account for only 12.8% of city area, while the most comprehensive dataset from the national land surveying agency reveals the figure of 61.2%. The former dataset, which excludes many types of green spaces (such as arable land, private and informal green spaces), is still the most commonly used. The analysis of the 17 other cities confirms the same pattern. This results in broader institutional failures related to urban green infrastructure planning, management, and research, including a lack of awareness of green space quality (e.g. connectivity) and benefits (ecosystem services), and the related political disregard for urban green spaces. Our comparison suggests that a better understanding of green space data sources is necessary in urban planning, and especially when planning urban green infrastructure.     

The potential of school green areas to improve urban green connectivity and multifunctionality

Urban green infrastructure supports resilience in cities and promotes sustainable resource management. Small green areas, including school green areas (SGAs), are an important component of urban green infrastructure, playing a key role in supplying cities with educational services. This article describes how SGAs can amplify an urban green area's connectivity and multifunctionality. The analysis was performed in Bucharest as a case study. A survey based on questionnaires was used to obtain data regarding green spaces within public schools. A total of 411 administrators from 461 public schools participated in the survey for a response rate of 89.1%. Information from the questionnaires was augmented with spatial data of SGAs and public green spaces, i.e., parks and city gardens. Using parametric and nonparametric statistical analysis, we first identified the variables that determine an SGA's presence and size. Potential connectivity assessment results showed that most of the schools that lack or have small-sized SGAs have the possibility to cover their green space deficit by developing activities within nearby public green spaces. A structural connectivity assessment of SGAs toward other public urban green areas revealed that SGAs are an important element of the urban environment by serving as stepping stones to species flow. The multifunctionality of the SGAs was emphasized through the educational services they provide, being involved in pupils’ daily activities. The increased connectivity and multifunctionality of urban green infrastructure through small, specialized green areas, such as SGAs, is an indicator of the fact that such areas can be used to ameliorate the deficit of green space in major urban areas.     

How to promote residents’ use of green space: An empirically grounded agent-based modeling approach

One focus of those responsible for making urban policies has been the improvement of green space effectiveness, including environmental plans and eco-city initiatives. In the evaluation of policy effectiveness, residents’ needs, values and preferences are critical but often overlooked. This study proposes an agent-based model (ABM) for simulating the effectiveness of policy measures on residents’ decision making with regard to the use of green space. Using a residential questionnaire survey conducted in Shanghai, China, we model individual decision making with artificial neural networks that account for the heterogeneous characteristics and imperfect rationality in the decision-making process, and compare three policy scenarios in local green space provision. The results of the model illustrate the unequal effectiveness of green space policies among different social groups and different types of green space (i.e., urban parks, neighborhood parks, and community gardens), and the sensitivity analysis suggests the key factors in different stages of green space provision. Based on the results, we argue that tailored policies are needed in order to meet residents’ heterogeneous needs; in fact, relatively “soft” policies, particularly those that promote social interaction and participation, play a significant role in the appeal of green space use. Finally, policy suggestions are provided for the optimization of green space provision.     

Linking ecosystem services,urban form and green space configuration using multivariate landscape metric analysis

Context

Landscape metrics represent powerful tools for quantifying landscape structure, but uncertainties persist around their interpretation. Urban settings add unique considerations, containing habitat structures driven by the surrounding built-up environment. Understanding urban ecosystems, however, should focus on the habitats rather than the matrix.

Objectives

We coupled a multivariate approach with landscape metric analysis to overcome existing shortcomings in interpretation. We then explored relationships between landscape characteristics and modelled ecosystem service provision.

Methods

We used principal component analysis and cluster analysis to isolate the most effective measures of landscape variability and then grouped habitat patches according to their attributes, independent of the surrounding urban form. We compared results to the modelled provision of three ecosystem services. Seven classes resulting from cluster analysis were separated primarily on patch area, and secondarily by measures of shape complexity and inter-patch distance.

Results

When compared to modelled ecosystem services, larger patches up to 10 ha in size consistently stored more carbon per area and supported more pollinators, while exhibiting a greater risk of soil erosion. Smaller, isolated patches showed the opposite, and patches larger than 10 ha exhibited no additional areal benefit.

Conclusions

Multivariate landscape metric analysis offers greater confidence and consistency than analysing landscape metrics individually. Independent classification avoids the influence of the urban matrix surrounding habitats of interest, and allows patches to be grouped according to their own attributes. Such a grouping is useful as it may correlate more strongly with the characteristics of landscape structure that directly affect ecosystem function.

     

Global patterns in urban green space are strongly linked to human development and population density

Urban green space is important for alleviating high temperatures, pollution, and flooding in cities. Furthermore, it is becoming increasingly clear that urban green space is important for the mental and physical health of humans residing in cities and that urban green space may harbor unique biodiversity. Understanding the extent and drivers of urban green space is thus important. While urban green space has been mapped and studied at local to national scales, the global patterns and drivers of urban green space remain unknown, potentially hampering effective planning and allocation of resources toward reaching sustainable development goals. Here, we quantified the effect of environmental and socio-economic drivers (temperature, precipitation, human development, and population density) on urban green space globally by focusing on national capital cities. We used satellite imagery to map urban green space using two measures: the Normalized Difference Vegetation Index (NDVI), and the fractional cover of “green” land cover classes. NDVI is useful as it includes all vegetated surfaces, also small ones like gardens. However, land cover classes allow the exclusion of certain classes such as sports fields or cropland. We used boosted regression trees to show that climatic variables accounted for 75 % of the relative influence in urban green space, with a positive effect of precipitation and a negative effect of temperature. Importantly, socioeconomic variables accounted for 25 % of the influence on global urban green space, with a positive effect of human development index (HDI) and a negative effect of population density. HDI in relation to urban green space has not previously been tested globally, and our study shows that significantly affects urban greenspace. The results demonstrate that cities where development status is low and population densities are high, typically in the Global South, have less urban green space than the climate would predict. The results therefore suggest that human wellbeing does not only benefit directly from increasing human development and decreasing population densities in urban areas, but that these effects may be compounded by also improving nature’s contribution to people.