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Who has access to urban vegetation? A spatial analysis of distributional green equity in 10 US cities
Abstract
This research examines the distributional equity of urban vegetation in 10 US urbanized areas using very high resolution land cover data and census data. Urban vegetation is characterized three ways in the analysis (mixed vegetation, woody vegetation, and public parks), to reflect the variable ecosystem services provided by different types of urban vegetation. Data are analyzed at the block group and census tract levels using Spearman's correlations and spatial autoregressive models. There is a strong positive correlation between urban vegetation and higher education and income across most cities. Negative correlations between racialized minority status and urban vegetation are observed but are weaker and less common in multivariate analyses that include additional variables such as education, income, and population density. Park area is more equitably distributed than mixed and woody vegetation, although inequities exist across all cities and vegetation types. The study finds that education and income are most strongly associated with urban vegetation distribution but that various other factors contribute to patterns of urban vegetation distribution, with specific patterns of inequity varying by local context. These results highlight the importance of different urban vegetation measures and suggest potential solutions to the problem of urban green inequity. Cities can use our results to inform decision making focused on improving environmental justice in urban settings. Full text available here: https://authors.elsevier.com/a/1XpvAcUG5AoX~
... The spatiotemporal differences and changes in urban vegetation metrics are often clearly associated with identifiable socioeconomic factors. For example, previous studies suggest urban greenness can be negatively correlated with non-White racial composition and the density of the population, and positively correlated with house value, educational level, and income (Nesbitt et al., 2019;Litvak et al., 2017;). In the United States, low-income urban neighborhoods tend to have high soil impermeability, less vegetation, and lower greenness. ...
... In the United States, low-income urban neighborhoods tend to have high soil impermeability, less vegetation, and lower greenness. Race and economic conditions can be important indicators of access to green spaces (Nesbitt et al, 2019;Ogneva-Himmelberger et al., 2009;Wen et al., 2013). This raises important questions about how to reduce and eliminate the vegetation-related health inequalities associated with geographic location, race, housing, and economic disparity (Marmot & Bell, 2016). ...
... Referring to previous studies related to urban vegetation inequality, we selected the following socioeconomic variables showed in Table 2 (Lin et al., 2017;Mennis, 2006;Nesbitt et al., 2019). As the sizes of the census tracts differ in area, we divided the population of each racial subgroup by the census tract area to estimate the population 9 density. ...
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Urban vegetation is valuable in alleviating local heatwaves. However, drought may decrease vegetation health and limit this cooling effect. Here we use the satellite-based Normalized Difference Vegetation Index (NDVI) and Palmer Drought Severity Index (PDSI) to investigate the sensitivity of urban vegetation to drought in the Coastal Greater Los Angeles from 2001 to 2020. We applied four statistical models to analyze the relations between 15 socioeconomic variables and the vegetation’s sensitivity to drought. We then examined the changes in the cooling effect of the urban vegetation during drought and non-drought periods using remotely sensed land surface temperature (LST) data. The results suggest that areas that are economically disadvantaged and have higher proportions of Hispanics and Blacks are typified by more sensitive vegetation to drought, which is likely linked to inequality in water use. Moreover, these populations experience a lower degree of vegetation cooling effects and higher exposure to heatwaves. The findings of this study imply that the potential of a community’s vegetation in mitigating heatwaves is significantly influenced by the socioeconomic conditions of the community. Increasing resilience of urban vegetation to drought over the disadvantaged communities may help promote environmentally sustainable and socially resilient cities under a warming climate.
... Thus, exisiting environmental justice literature has yielded inconsistent and inconclusive results (Wang et al., 2021). For example, while some studies have found that racial minorities and socioeconomically disadvantaged populations tend to have less access to urban greenspaces in terms of proximity, quantity, and quality (Nesbitt et al., 2019;Rigolon & Flohr, 2014;Wolch et al., 2005;Zhou & Kim, 2013), others have shown mixed results in a way that some park access measures such as proximity have favored low socioeconomic groups (Boone et al., 2009;Heckert, 2013;Mears et al., 2019). Most existing literature on park inequity presenting inconclusive results have one of the following gaps: (1) using Euclidean distance without considering the real street networks to examine proximity; (2) not considering two or more dimensions of park access at the same time; ...
... Park quantity has been depicted most often by the number and acreage of parks or the acreage per 1000 persons, known as the container and coverage approach based on Talen's framework (Maroko et al., 2009;Mears et al., 2019;Nesbitt et al., 2019;Rigolon, 2016;Rigolon & Nemeth, 2014;Silva et al., 2018;Talen & Anselin, 1998;Vaughan et al., 2013;Wolch et al., 2005;Xu et al., 2018). Although this approach is used most often due to its ease of data acquisition and calculation, the drawbacks have also been identified as a modifiable areal unit problem (MAUP) and the assumption that people only go to parks within the geographic units considered (Wang et al., 2021). ...
... This study advances the methodology of examining park equity in three ways. First, unlike most existing studies that have only considered a single dimension of the three park access measures (i.e., proximity, quantity and quality) (Nesbitt et al., 2019;Rigolon, 2016), this study examined three dimensions of park access: park proximity, congestion, and park crime. The findings revealed that considering more than one aspect of park access is important for an unbiased municipal park equity assessment. ...
Park inequity has been widely examined in U.S. cities, yet the results were inconclusive. This gap is possibly because of the consideration of one single aspect of access at a time and the lack of examination of spatial dependency and heterogeneity when modeling the relationship between park access and the socioeconomic status of populations. This study aims to contribute to these gaps in the studies of park equity by investigating park inequity using three access measures—park proximity, park congestion, and park crime—in Hartford, Connecticut. As a result, park proximity, park congestion, and park crime presented distinct spatial patterns and low correlations with each other. In addition, the results of geographically weighted regressions uncovered spatial heterogeneity in the relationships between the three park access measures and socioeconomic variables and confirmed that the relationships are location-specific with varying magnitudes and signs of the coefficients. In particular, median house value was associated with less park crowdedness particularly in White and Hispanic neighborhoods. Furthermore, southern neighborhoods showed more park crime disparities in relation to race, education, and income levels. The multidimensional and spatially heterogeneous patterns of park inequity inform urban planning on how to strategically allocate resources in pursuit of environmental justice.
... By examining the spatial configuration of trees at different scales within a city, geographical analysis can provide a broader insight into the optimisation of urban tree locations and benefits (Cowett, 2014;Jim, 1989). Some studies had sought to investigate the spatial patterns of urban vegetation distributions, but they tended to aggregate tree counts into different areal units such as land parcels (Bigsby et al., 2014), block groups (Schwarz et al., 2015), and census tracts (Nesbitt et al., 2019), or neglect the differences in tree species and size by analysing tree canopy covers and densities in general (Aabeyir et al., 2022;Locke et al., 2016). There are only very few models that incorporate both the physical environments and the spatial patterns of individual trees into urban forest simulation, including the CITYgreen model (Peng et al., 2008), which utilises land covers, rainfall, soil types and slope to form a spatial database, and the UrbTree model (Kramer and Oldengarm, 2010), which applies the distances from buildings, roads and neighbouring trees, and penetrable surfaces to estimate the limiting factors for tree growth. ...
... Some existing studies in Hong Kong had attempted to explore the potential differences in species compositions between older and newer public housing estates (Jim and Zhang, 2015), commercial sky gardens (Law et al., 2021) and urban parks (Wang and Zhang, 2022). Examples in foreign cities also showed that neighbourhood ages were significantly correlated with tree abundances in Europe (Klobucar et al., 2021), as well as the tree covers and diversities in the USA Nesbitt et al., 2019). In this study, the study area was divided into three zones with various development histories and urban forms, which resulted in different species patterns in terms of diversity and similarity indices (Table 2). ...
... In addition to the proximity to nearby features, the spatial properties among tree locations were extracted as variables in SEM, including the geographical distribution and spatial dependence of every point. Many studies had utilised spatial lag models to analyse tree coverages (Nesbitt et al., 2019;Schwarz et al., 2015), but only a few of them investigated the spatial properties of individual trees, despite being the fundamental unit in forestry analysis (Kandare et al., 2016). Some researchers had revealed that closely planted trees and competition with neighbours would alter crown shapes and lead to health decline (Bayer et al., 2018;Law et al., 2021). ...
Trees in the urban environment are affected by a range of place-specific environmental and cultural factors. Nevertheless, many factors interact with each other and produce high variabilities in urban forest structures, spatial configurations, and growing conditions within the urban fabric. The variabilities and relationships among these factors require a modelling framework that incorporates variables related to the spatio-temporal information of individual trees and site characteristics. Using roadside trees in a residential district in Hong Kong, this study examined their species compositions and spatial distributions among zones with various development histories. Structural equation modelling was applied to investigate the interactions among variables concerning the physical environment, temporal changes, species selection, spatial patterns, and tree sizes. A few abundant species dominated the urban forest, with uneven distributions of roadside tree densities and species-specific clusters found within the study area. The empirical results showed (i) the physical environment influenced the existence of roadside trees, the occurrence of specific species and tree growth; (ii) species selection mediated the influences of the physical environment on tree sizes and spatial patterns; (iii) despite the linkage between existing tree patterns and development histories, replacement plantings further modified the compositions and reflected a shift in preferences; (iv) the proximity to nearby urban structures and the spatial properties among planting locations were important factors in spatial planning. Hence, urban forest managers play a crucial role in mediating the interactions among physical drivers, planting histories, and tree performances. It is recommended that species diversity, especially native trees, should be promoted within the study area, while planting strategies matching site dimensions, species and attainable sizes should also be prioritised. By generalising the relative effects that determined the existing patterns of urban forests, the modelling framework can provide a strategic reference for target-oriented tree management in Hong Kong and other cities.
... To disentangle the ways in which accessibility and engagement with urban nature may relate to feelings of inclusion/exclusion within and across city landscapes, we turn to the framework of urban green equity proposed by Nesbitt, Meitner, Sheppard, and Girling (2018) ;Nesbitt, Meitner, Girling, Sheppard, and Lu, (2019b). Urban green equity, an important mediator in people's relationship with nature, is defined as ''fair access to and governance of urban vegetation regardless of differentiating factors such as socioeconomic status, race, culture, or age'' (Nesbitt et al., 2018, p. 241) and includes two principal dimensions: distributional equity and recognitional equity. ...
... The spatial distribution of urban nature, which is inclusive of the sub-dimensions of temporality (e.g., historical context; seasonality; leisure time), condition and preference (e.g., quality of urban vegetation; sociocultural landscape preferences), and ownership (e.g., public vs. private land), is referred to as distributional equity within Nesbitt et al.'s (2018) framework. In the United States, the distribution of urban nature is unequal within and across urban environments (Landry & Chakraborty, 2009;Nesbitt et al., 2019b;Nyelele & Kroll, 2020;Rigolon, Browning, & Jennings, 2018;Trust for Public Land, 2020Zhou & Kim, 2013). ...
... Drawing from a year-long, PAR project that used photography, writing, and mapping as diverse vehicles for storytelling, this work explores the role that urban nature plays in community college students' sense of belonging to their immediate communities and to NYC at large. Situated within the framework of urban green equity (Nesbitt et al., 2018(Nesbitt et al., , 2019b, we explore the ways in which people's notions of urban nature, including its quality and accessibility, among other characteristics, can play a role in fostering a sense of community and belonging to a place, or contributing to feelings of marginalization and disenfranchisement. ...
... Moreover, two studies showed that patterns of natural environment inequity varied by measure of the natural environment considered. 14,15 Different measures of the natural environment (e.g., greenness, parks, or tree cover) capture different aspects of the natural environment that may result in differing associations between studies. For example, the Normalized Difference Vegetation Index (NDVI) captures private greenery (backyards) and could therefore be more strongly related to SES measures than parks. ...
... Models included median household income / %<poverty level/%<high school education and were adjusted for median age, population density, temperature, precipitation, %non-Hispanic White, %non-Hispanic Black, %non-Hispanic Asian, %non-Hispanic other, %Hispanic, and latitude and longitude of the centroid. For all census tracts, the following percentiles (20, 40, In general, we observed that SES was more strongly associated with NDVI compared with park cover, which supports findings by Nesbitt et al. 15 This is probably because NDVI captures street and private greenery, which may contain a large portion of the total greenness in urban areas, and high SES neighborhoods generally have larger residential properties. We also observed a very weak correlation between NDVI and park cover in urban tracts (Spearman rho = 0:11). ...
Background:
Several studies have evaluated whether the distribution of natural environments differs between marginalized and privileged neighborhoods. However, most studies restricted their analyses to a single or handful of cities and used different natural environment measures.
Objectives:
We evaluated whether natural environments are inequitably distributed based on socioeconomic status (SES) and race/ethnicity in the contiguous United States.
Methods:
We obtained SES and race/ethnicity data (2015-2019) for all U.S. Census tracts. For each tract, we calculated the Normalized Different Vegetation Index (NDVI) for 2020, NatureScore (a proprietary measure of the quantity and quality of natural elements) for 2019, park cover for 2020, and blue space for 1984-2018. We used generalized additive models with adjustment for potential confounders and spatial autocorrelation to evaluate associations of SES and race/ethnicity with NDVI, NatureScore, park cover, and odds of containing blue space in all tracts (n=71,532) and in urban tracts (n=45,338). To compare effect estimates, we standardized NDVI, NatureScore, and park cover so that beta coefficients presented a percentage increase or decrease of the standard deviation (SD).
Results:
Tracts with higher SES had higher NDVI, NatureScore, park cover, and odds of containing blue space. For example, urban tracts in the highest median household income quintile had higher NDVI [44.8% of the SD (95% CI: 42.8, 46.8)] and park cover [16.2% of the SD (95% CI: 13.5, 19.0)] compared with urban tracts in the lowest median household income quintile. Across all tracts, a lower percentage of non-Hispanic White individuals and a higher percentage of Hispanic individuals were associated with lower NDVI and NatureScore. In urban tracts, we observed weak positive associations between percentage non-Hispanic Black and NDVI, NatureScore, and park cover; we did not find any clear associations for percentage Hispanics.
Discussion:
Multiple facets of the natural environment are inequitably distributed in the contiguous United States. https://doi.org/10.1289/EHP11164.
... This threshold is determined for two reasons. First, 1,000 m (or 10-15 min) is an acceptable walking distance for residents to visit the park green space (You, 2016;Žlender and Ward Thompson, 2016;Guo et al., 2019;Nesbitt et al., 2019;Tu et al., 2020). In addition, the Gaussian-based two-step floating catchment area method itself accounts for the travel friction effect. ...
... The first limitation of this study is the determination of distance threshold. At present, the distance threshold values that were used include 300 m (Schipperijn et al., 2010a;Mears et al., 2019), 400 m (Tan and Samsudin, 2017;Wei, 2017), 500 m (Wüstemann et al., 2017), 600 m (Schipperijn et al., 2010b), 800 m (Wei, 2017), 1,000 m (You, 2016;Nesbitt et al., 2019;Tu et al., 2020), 1,200 m (Shen et al., 2017), 1,600 m (Xiao et al., 2017), or 10-20 min' walking distance Frontiers in Environmental Science frontiersin.org (Guo et al., 2019) and 15 min' walking distance (Žlender and Ward Thompson, 2016). ...
Park green space is an important ecological factor of the urban built-up environment, and it plays an increasingly important role in improving human welfare and the quality of urban life. Accessibility analysis of urban park green space is an issue of social equity and environmental justice that has received widespread attention. The accessibility of a city’s park green space must be evaluated under the correct scale and resolution before it can be applied to urban green space planning. To measure the impact of different research scales on accessibility, Weidu District of Xuchang City, Henan Province, China, was taken as the experimental area. The Gaussian-based two-step floating catchment area method was used to compare and analyze the accessibility differences under three scales: subdistrict, community, and residential quarter. The influence of the source and destination point modes on accessibility was analyzed at the residential quarter scale. Results show that the accessibility of park green space at the subdistrict scale is different from that at the community and residential quarter scales in terms of spatial distribution characteristics and quantitative relationship. The accessibility of the geometric center mode and the entrance and exit mode at the residential quarter scale is similar in overall distribution and different in local quantity. Overall, the accessibility of the park green space at the residential quarter scale under the entrance and exit mode and the spatial fairness of visiting the park green space are better than that under the geometric mode. Therefore, accessibility analysis of park green space should be performed cautiously when taking the aggregation unit as the basic research unit. The accessibility of the aggregation unit is not the statistical summary of its subunits, especially when the area of the aggregation unit is far larger than the walking range of residents, and is thus likely to lead to wrong conclusions. Accessibility analysis should be conducted on the finest scale possible rather than the aggregation scale and use true distance rather than the centroid-to-centroid surrogate to obtain reliable results for further guiding urban green space planning.
... Using the spectral mixture analysis (SMA) model on the large scale of Singapore, Masoudi et al. (2019) [15] found patches of UGS that were simpler in shape, more connected, and less fragmented had better cooling effect. Nesbitt et al. (2019) [16] used aerial imagery and census data to examine the distributional equity of UGS by using Spearman's correlations and spatial autoregressive models, and found that education and income were most strongly associated with the distribution of UGS. Barbierato et al. (2020) [17] combined remote sensing and proximate sensing (Street View) approaches with data retrieved from Google Street View, and divided urban forest into two categories including green cover on facades and green cover on sky view to quantify urban forest ecosystem services score. ...
... Using the spectral mixture analysis (SMA) model on the large scale of Singapore, Masoudi et al. (2019) [15] found patches of UGS that were simpler in shape, more connected, and less fragmented had better cooling effect. Nesbitt et al. (2019) [16] used aerial imagery and census data to examine the distributional equity of UGS by using Spearman's correlations and spatial autoregressive models, and found that education and income were most strongly associated with the distribution of UGS. Barbierato et al. (2020) [17] combined remote sensing and proximate sensing (Street View) approaches with data retrieved from Google Street View, and divided urban forest into two categories including green cover on facades and green cover on sky view to quantify urban forest ecosystem services score. ...
With the rapid development of urbanization, it is an important goal for urban green space (UGS) to meet the needs of residents’ production and life using a supply–demand evaluation method of ecosystem service (ES). However, most studies have considered all functional types of UGS as the supply side, or rely solely on a single supply or demand side to conduct ecosystem service function (ESF) evaluation, resulting in less accurate and targeted research findings. As a result, a novel methodological framework for matching each ESF with corresponding functional types of UGS, and considering both supply and demand sides have been required. Firstly, the object-oriented approach combining support vector machine (SVM) and normalized difference vegetation index (NDVI) was used to automatically identify UGS, and integrated Point of Interest (POI), urban built-up area, road land, parcel, and socio-economic data to classify six functional types of UGS using the near-convex-hull. Next, matching the functional types of UGS with five ESFs, both supply and demand status were evaluated using the carbon sequestration and release analysis, Gaussian two-step floating catchment area, and spatial equilibrium degree methods. This method was demonstrated in Beijing, China. The results show: (1) the ES supply–demand situation provided by each functional type of UGS is different in five ESFs; (2) considering both supply and demand is more intuitive to see whether the city’s demand for UGS has been met. Our results provide a new perspective for evaluating the contribution of UGS and have practical implications for UGS planning.
... Second, we speculate that most closed communities of commercial housing may be provided with green spaces and entertainment facilities (Li, Zhu, and Li 2012), which can meet the daily community leisure activities of wealthy families. Besides, Jennings and Gaither (2015) found that an unfair distribution of green areas was related to health differences and that low-income groups tended to experience poor living environments (Nesbitt et al. 2019). Full exposure to green vegetation can mitigate negative environmental impacts (Wolch, Byrne, and Newell 2014), so low-income residents may have more access to parks than others. ...
... This trend may also explain why rich communities have poor access to parks in our results. Nesbitt et al. (2019) pointed out that private land usually contains a large part of urban vegetation, thereby making this land an important contributor to solving the inequality in the allocation of green spaces. However, as we are unable to distinguish public from private lands except for the park area in Taiyuan, we cannot prove that the green spaces in private or public land are indeed the main cause of inequity. ...
The scarcity of public resources and environmental pollution caused by rapid urbanization highlight the practical significance of parks in ensuring the sustainable development of a city. Therefore, the social equity of parks warrants further study. This paper proposes a fine-grained comprehensive evaluation framework that combines geographic accessibility models, geo-statistical analysis, and machine learning algorithms to explore social inequity in Taiyuan, China. In this framework, gini coefficient and lorentz curve express spatial equality, accessibility shows spatial equity, and ridge regression model handles the interdependence of variables with different dimensions to quantify the relative effects of local participants on changes in park accessibility. On this basis, the imbalance between vulnerable groups and park supply is analyzed to further understand the core concept of social equity. Results highlight serious spatial inequality in all three types of parks allocation of six urban areas, especially in community parks. The actual access level of people to parks is also stratified by their demographic and socioeconomic characteristics, revealing the social inequity in access to parks. Park distribution is indeed not conducive to some social vulnerable groups, whose contradiction between supply and demand is highly prominent in urban – rural junctions and new urban areas. This paper also confirms the unfair layout of public facilities can be observed in second-tier cities of China by highlighting the social inequity of parks in Taiyuan. The findings of this work have profound implications for urban planning and sustainable development.
... In addressing the social differentiation and spatial segregation in the process of urbanization, spatial equity during the process of urban regeneration among cities around the world has been receiving increasing attention [1][2][3][4][5][6][7][8][9][10]. Especially in China, most cities have experienced extremely rapid urbanization in recent decades. ...
... To fill the conceptual and methodological limitations of the above reviews, we focus on three specific questions in this study: (1) How to effectively measure the accessibility of urban parks? (2) What are the characteristics of accessibility distribution both at the neighborhood scale and the urban ring scale? (3) What is the accessibility pattern across the city and how do accessibility types differ? ...
The distribution of urban parks is closely related to the opportunities of daily use by residents as well as the performance of the park system. The question as to whether parks are distributed equitably within cities is therefore becoming the focus of attention. However, only a few studies have explored a comprehensive and systematic procedure for urban park accessibility analysis and equity evaluation. In this study, by applying an improved two-step floating catchment area (2SFCA) method and K-means cluster analysis, based on the application of multi-source data, we provide insights into an equity study on park accessibility at the neighborhood scale and urban ring scale in the central urban area of Zhengzhou. These results suggest that the spatial access to parks in Zhengzhou is generally unevenly distributed among neighborhoods, and both the mean and standard deviation of accessibility show an increase from the center to the periphery. The cluster analysis reveals a set of four types of neighborhoods, including a high-supply medium-demand medium-accessibility type (HMM), a low-supply medium-demand low-accessibility type (LML), a high-supply low-demand high-accessibility type (HLH), and a medium-supply high-demand low-accessibility type (MHL), each with different characteristics and causes. The spatial distribution of the accessibility types exhibits both similarities and differences between the urban rings. The findings of this study could serve as a tool for identifying areas in which parks are underserved and the ways in which they differ from other areas, which can guide urban planning to address specific inequities.
... This land is usually costly, which is not affordable to everyone. A study carried out in 10 metro areas in the U.S. found that the distributional equality of urban green space significantly depended on higher education, higher income, and race except for two metro areas-Jacksonville, FL, and St. Louis, MO-IL, less-educated and Latino populations had more access to green spaces [65]. Arguably, income and education highly influence housing area and park establishment (one form of green space) in urban areas. ...
Urban green space, comprising parks, fields, woodlands, and other semi-natural areas, is a fundamental component of urban ecosystems. The determination of the relationship between urban green space and urban sprawl is necessary to understand urbanization and the provision of urban ecosystem services. It has been hypothesized that the center of urban (i.e., population and economic) areas in fast-growing cities would migrate toward urban green space over time. To test this hypothesis, urban expansion and urban green space expansion were examined in five cities in China and five cities in the U.S. that were experiencing high rates of growth. Landsat images of those cities from 2000 to 2017 were combined with annual population and economic data and used to quantify the extent and migration of the urban green space. These data were analyzed using the center of gravity method by Grether and Mathys and circular statistics were used to determine the relationship between urban green space and urban expansion. Eight out of the ten cities showed a divergent pattern, i.e., the population and economic centers moved in a different direction to that of the urban green space. The movement of the mean centers of the urban green spaces in the U.S. cities was more consistent than that of the Chinese cities. Over 18 years, the movement of urban green space and urban expansion in the 10 cities showed a synchronous growth trend; however, the proportion of urban green space in the cities decreased. The urban expansion rate exceeded the population growth rate, which led to problems with an unreasonable urban sprawl that is likely to deplete the provision of ecosystem services in the future. In conclusion, the centrifugal forces of urban green space that lead to the movement of population and economic centers away from green spaces play a larger role in urban change than the centripetal forces that pull these centers toward urban green space.
... Moreover, the NDVI value can only represent the lushness of UGS; that is, it lacks consideration of the overall landscape pattern of UGS, such as the different types of forests, grasslands, and street trees [58]. In addition, there is a lack of consideration of social factors, such as the difference between park UGS and private community UGS [62]. Although the NDVI values of these different types of UGS are similar, they have a great impact on the assessment of residential exposure to green space, which is an aspect that needs to be considered in future research. ...
Urban green space has a critical impact on the urban ecological environment, residents’ health, and urban sustainability. Quantifying residential exposure to green space and proposing targeted enhancement strategies in urban areas is helpful to rationally plan urban green space construction, reduce the inequality in residential exposure to green space, and promote environmental equity. However, the long-time evolution analysis of residential exposure to green space at different scales and the influence of green space quality on residential exposure to green space are rarely reported. Here we produced a long-time series dataset of urban green space from 1990 to 2020 based on the 30 m Landsat data and used the Normalized Difference Vegetation Index (NDVI) as a representation of the green space quality to comprehensively analyze residential exposure to green space at the city and block scales within the 5th ring of Beijing, China. We found that the urban green space in Beijing is mainly distributed in urban areas between the 4th and 5th rings (i.e., 153.4 km2 in 2020), and there is little green space within the 2nd ring area (i.e., 12.6 km2 in 2020). There is clear spatial inequality in residential exposure to green space, and about 2.88 million (i.e., ~27%) residents have experienced different degrees of decline in residential exposure to green space from 2015 to 2020. However, the degree of inequality in residential exposure to green space has gradually weakened from a high level (Palma ratio = 2.84) in 1990 to a relatively low level (Palma ratio = 0.81) in 2020. In addition, the spatial-temporal analysis method of residential exposure to green space based on green space quality has certain advantages that can help explore the degraded and lost areas of green space.
... As a major part of sustainable urban development, vegetation plays an important role in providing ecological services in urban areas [7,[19][20][21]. Previous studies have shown that two major driving factors affect vegetation dynamics in urban areas [19,22,23]. ...
Accompanied by China’s rapid economic growth, significant urban greening has occurred in Chinese cities, in particular in the urban core areas. In contrast, rapid urbanization and economic growth also led to a high probability of vegetation degradation in urban fringe regions. However, these significant spatial differences in urban greenness associated with economic growth in Chinese cities are not well understood. This study explored the spatiotemporal characteristics of the nighttime light (NTL) and annual maximum enhanced vegetation index (EVImax) in urban areas from 2001 to 2020. A strong decoupling status between economic growth and urban greenness on the national scale was found. Overall, 49.15% of urban areas showed a decoupling status. Spatially, this percentage of urban areas with a decoupling status would significantly decrease when the long-term average NTL surpasses 51. Moreover, this significant threshold of decoupling status was found in 189 cities out of 344 (54.65%) in China. This threshold in each city showed significant spatial heterogeneity but can mostly be attributed to the gradient in the long-term average precipitation (Pmean) of each city during the period of 2001–2020. Specifically, a spatial increase in Pmean of 100 mm responded to a decrease in the threshold of 0.4 DN (p < 0.01). In contrast, there was no significant correlation between the threshold and the economic growth status of each city. Our results provide valuable insights for coordinating the development of urban greening and economic growth.
... In many cities there is an unequal distribution of GI due to the decisions taken historically by planners and politicians. Consequently, we can identify significant variation in the types of GI, the quantity of GI and quality of those resources depending on where you live (Nesbitt et al., 2019). Within the research and practice literature, a series of benchmarks and metrics have been used to assess the ways in which GI are seen to be accessible. ...
Green Infrastructure is discussed to mean different things in alternative geographical, ecological and socio-economic contexts. However, the growing literature focussing on what Green Infrastructure is, what it does and how it should be delivered provides a baseline set of principles that help to situate the concept in academic and practice-based debates. The promotion of connected landscapes that are multi-functional that provide access to nature at the local, city and regional scale is central to Green Infrastructure thinking. Moreover, the need to integrate socio-economic and ecological perspectives into political decision-making has been repeatedly outlined as a key variable to successful policy creation and subsequent implementation. It is also important to align current Green Infrastructure thinking with the historical antecedents of greenspace planning to examine where complementarities can be identified between the past and the present. Overall, this introductory chapter sets out the principles and history of Green Infrastructure planning illustrating the nexus of people, policy and practice that permeates through the following chapters. It also outlines the broader parameters of the debates to come and grounds them in accepted principles of existing Green Infrastructure thinking. Since the introduction of Green Infrastructure as a concept, many things have changed in how territories and city organisations use it within the context of planning. One of the remaining unresolved issues is its relationship with the landscape. To some extent, ‘landscape’ was the instrument that spatial planning used to introduce ecological elements that may otherwise have been difficult to embed within planning. When additional instruments emerged, such as Green Infrastructure, which was considered to be focussed on ecological issues, greater difficulties in implementation began. Through this paper, we will always capitalise both – ‘Green Infrastructure’ and ‘landscape’ – in order to use them as terms of reference, both to complement each other and to juxtapose them. It is understood that the expression Green Infrastructure also covers Blue Infrastructure, i.e. aquatic ecosystems.
... Bibby et al. 2021;Haaland & Konijnendijk van den Bosch 2015;Nesbitt et al. 2018;Martino et al. 2021) ...
Municipalities face the direct impact of climate change events, but many are challenged to assess the potential outcomes of future climate action policies. It is essential for local municipalities to be able to evaluate cross-sector and cross-scale policy interventions, but many lack the expertise and resources for wholistic forecasting. This paper used a hybrid inter-scalar and interdisciplinary modeling approach to evaluate, compare, visualize, and reveal the performance of climate actions at building and neighbourhood scales of future ‘what-if’ scenarios for three neighbourhood urban form types (dispersed, corridor, nodal) in three cities in British Columbia, Canada (Vancouver, Victoria, Prince George). Results found that increases in population density combined with strict building standards and retrofitting older buildings decreased per person emissions per year by up to 84% by 2050. Within the neighbourhood-scale areas, building form and location had less impact. Population density and frequency of transit service were most important for mobility mode shifts. Concentrating density at transit nodes or along commercial corridors improved the percentages of residents within a five-minute walk of those services, but proximity to greenspaces showed mixed results. 'Policy relevance' Municipal climate action policies cross sectors and scales. This analysis of future urban form and energy scenarios at neighbourhood scales reveals livability and greenhouse gas (GHG) outcomes. It provides evidence that compact neighbourhood form coupled with stringent building codes reduces GHG emissions. (1) Concentrating density at transit nodes or along commercial corridors improved the percentages of residents within a five-minute walk of those services, but proximity to greenspaces showed mixed results. (2) Within neighbourhood-scale areas urban form (building form and location) had less influence on shifting mobility modes than did overall population density and transit frequency. (3) British Columbia’s net-zero-ready building code, a performance-based code, resulted in notable energy-use reductions and related emissions reductions associated with the new building stock. (4) Retrofitting the existing building stock resulted in notable emissions reductions in the three neighbourhoods; however, for cities with growing high land value, the potential for sale and redevelopment is a disincentive to retrofitting.
... Researchers have responded with studies on this topic in multiple jurisdictions, analyzing whether low-income, less-educated, or racialized-that is, those who have been marginalized owing to the societal assignment of a specific racial identity-populations are less likely to have access to urban green 5-7 and blue 8 spaces. In general, we now know that populations with higher incomes and more education have better access to green and blue spaces, especially in cities, 5,7,9 whereas associations between greenness and racialization are variable. 10 Klompmaker et al. 11 contribute to this growing body of evidence with an analysis of the distributional equity of natural environments in all census tracts in the contiguous United States. ...
... Several reasons might explain why greenness has limited equity impacts. First, natural disparities are prevalent, with disadvantaged subpopulations (e.g., low-income residents, and minorities) and vulnerable groups (e.g., young children and the elderly) often associated with less access to greenspace, lower tree cover, and fewer tree-derived ecosystem services than their advantaged and affluent counterparts (Gerrish and Watkins, 2018;Lin, Wang, & Li, 2021b;Nesbitt, Meitner, Girling, Sheppard, & Lu, 2019). Second, how people live, work, play, and interact with greenspace may aggregate the existing natural disparities. ...
Human exposure to greenness is associated with COVID-19 prevalence and severity, but most relevant research
has focused on the relationships between greenness and COVID-19 infection rates. In contrast, relatively little is
known about the associations between greenness and COVID-19 hospitalizations and deaths, which are important
for risk assessment, resource allocation, and intervention strategies. Moreover, it is unclear whether
greenness could help reduce health inequities by offering more benefits to disadvantaged populations. Here, we
estimated the associations between availability of greenness (expressed as population-density-weighted
normalized difference vegetation index) and COVID-19 outcomes across the urban–rural continuum gradient
in the United States using generalized additive models with a negative binomial distribution. We aggregated
individual COVID-19 records at the county level, which includes 3,040 counties for COVID-19 case infection
rates, 1,397 counties for case hospitalization rates, and 1,305 counties for case fatality rates. Our area-level
ecological study suggests that although availability of greenness shows null relationships with COVID-19 case
hospitalization and fatality rates, COVID-19 infection rate is statistically significant and negatively associated
with more greenness availability. When performing stratified analyses by different sociodemographic groups,
availability of greenness shows stronger negative associations for men than for women, and for adults than for
the elderly. This indicates that greenness might have greater health benefits for the former than the latter, and
thus has limited effects for ameliorating COVID-19 related inequity. The revealed greenness-COVID-19 links
across different space, time and sociodemographic groups provide working hypotheses for the targeted design of
nature-based interventions and greening policies to benefit human well-being and reduce health inequity. This
has important implications for the post-pandemic recovery and future public health crises.
... The environmental justice (EJ) literature suggests that strong spatial inequities exist within urban environments, with low-income and marginalized populations often unfairly burdened with disamenities and hazards such as environmental pollution [1][2][3], traffic and aviation noise [4,5], and flooding [6], while having reduced access to beneficial amenities such as high-quality parks and greenery [7][8][9], specialized medical facilities and care [10,11], grocery stores [12,13], and high-performing schools [14]. As the EJ literature has evolved and expanded over the past two decades [15], increased attention has been paid to potential inequities in the quality and structure of the built environment (e.g., [16][17][18][19]). ...
Walkable and transit-accessible neighborhoods that may offer residents numerous health, social, and economic benefits are, in many places, becoming increasingly exclusive. This equity-mapping analysis sought to determine whether socially vulnerable (SV) populations within America’s largest (pop. ≥ 500 k) metropolitan areas have equitable access to walkable and transit-accessible neighborhoods. The results suggest an equitable overlap between high-SV and highly walkable neighborhoods in many cities, yet there was significant variability in both the availability and equity in accessibility of these neighborhoods to SV populations. Concerningly, high-SV populations living in more walkable neighborhoods are also likely to contend with higher levels of personal crime (i.e., homicide, rape, robbery, assault), poorer-performing schools, and lower transit accessibility. While the primary challenge in some cities, including many in the South and Southeast, is a general lack of walkable and transit-accessible neighborhoods, in others a dearth of affordable housing is likely the main barrier to ensuring broad and equitable accessibility.
... The growing severity of "urban disease" poses great challenges to the physical and mental health of urban residents, restricting the sustainable development of the social economy. As an important part of the urban composite ecosystem [6], urban vegetation has significant ecological service functions in the construction of the urban ecological environment [7,8]. These functions include purifying the environment [9,10], conserving water and soil [4], regulating the urban microclimate [11], alleviating the "heat island effect" [6,12,13], storing carbon confluence [14,15], and maintenance of biodiversity [16], landscape appreciation, leisure and entertainment [8], cultural education, social interaction [17], ecological protection [18], drought and disaster reduction [19]. ...
As the main carbon sink in the carbon cycle process, vegetation is an important support for achieving "carbon peaking" and "carbon neutrality. How does the vegetation coverage of urban built-up areas change in the process of urbanization in China? Taking advantage of Landsat remote sensing data, we extract urban built-up areas, calculate the Normalized Difference Vegetation Index (NDVI), estimate fractional vegetation cover (FVC), and analyze the temporal and spatial dynamics of vegetation coverage in built-up areas of provincial capitals from the national and individual city levels in China. Major conclusions are as follows: (1) The FVC in the urban built-up areas has increased by 7.97%, and the urban green space has gradually changed from the "green core" distribution model to the "green vein" distribution mode. (2) The disparities in FVC of built-up areas of provincial capitals are notable, presumably due to a variety of factors that include the natural geographic environment, economic development level, built-up area expansion, land type conversion, afforestation of greening policy, etc. (3) Not just simply raise or lower, the FVC curves in the built-up areas of provincial capital cities present oscillating patterns with gradually weakening amplitude. Our study is expected to provide scientific references of an important theoretical basis for urban ecological construction and practical support for promoting the harmonious development of urban residents and urban environments in China.
... It is important to note that demographic characteristics of respondents may be interacting in complex ways with perceptions of environmental concerns. For example, higher income is often associated with "greener" neighborhoods and differences in environmental concerns (Nesbitt et al. 2019). However, the relationship between landcover and perceptions of environmental problems remained when demographic differences were accounted for in our models. ...
The relationship between (a) the structure and composition of the landscape around an individual's home and (b) environmental perceptions and health outcomes has been well demonstrated (eg the value of vegetation cover to well‐being). Few studies, however, have examined how multiple landscape features (eg vegetation and water cover) relate to perceptions of multiple environmental problems (eg air or water quality) and whether those relationships hold over time. We utilized a long‐term dataset of geolocated telephone surveys in Baltimore, Maryland, to identify relationships between residents’ perceptions of environmental problems and nearby landcover. Residents of neighborhoods with more vegetation or located closer to water were less likely to perceive environmental problems. Water quality was one exception to this trend, in that people were more likely to perceive water‐quality problems when nearby water cover was greater. These trends endured over time, suggesting that these relationships are stable and therefore useful for informing policy aimed at minimizing perceived environmental problems.
... The main threats are a lack of funding, occasional droughts, and the high, ever-increasing price of water, which hinder the poor from greening their outdoor spaces. The LST-R is accomplished using location, quantification, and equity of measures [33][34][35] . The mapping of roads by width, if they do not already exist in the municipal geodatabase, can be derived from the VHR satellite imagery accessible from GE Pro. ...
Over the next 30 years, temperatures are expected to increase in hot semi-arid zones. Despite increasing studies on urban heat, cooling measures suitable for this climate zone remain poorly investigated. The proposed method is innovative because it focuses on significant landscape metrics for determining the land surface temperature (LST) and evaluating cooling measures. Recurrence of warm spells was identified analysing the daily air temperatures. Daytime and night-time LST data acquired from space were correlated with landscape metrics extracted from very high-resolution satellite imagery. Stepwise linear regression was used to identify the significant metrics that affected it. Cooling measures were selected considering implementation leeway; performance of existing measures; strengths, weaknesses, opportunities, and threats, equity analyses. Although the method was tested in Niamey, Niger, it can be applied to any city or town in hot semi-arid Global South, requiring decision-making support on cooling policies.
• Landscape metrics are consistent with development standard and general requirements
• Evaluation of measures to reduce land surface temperature includes experts’ advice
• Equity of measures to reduce land surface temperature is considered
... Sociodemographic characteristics were retrieved from 2015-2019 American Community Survey (ACS) estimates from the U.S. Census at the county and tract level 67 . We selected 14 variables (Table S2) based on existing literature examining correlates of greenspace, especially in studies focusing on socioeconomic and racial disparities in access to these spaces [68][69][70][71][72] . Attempts at incorporating median household income alongside other measures resulted in multicollinearity, so this variable was excluded from the primary analyses but considered in a sensitivity analysis. ...
Most spatial epidemiological studies of nature-health relationships use generalized greenspace measures. For instance, coarse-resolution spatial data containing normalized difference vegetative index (NDVI) values are prominent despite criticisms, such as the inability to restrain exposure estimates to public and private land. Non-threatening natural landscapes can improve health by building capacities for health-promoting behaviors. Recreational and accessible parks may best activate such behaviors. We curated the Parks and Protected Areas Database of the U.S. (PAD-US) to identify parks that are accessible for outdoor recreation. Our title adds “AR” to “PAD-US” where A = Accessible and R = Recreational. We validated the PAD-US-AR by comparisons with greenspace datasets and sociodemographics, which demonstrated its uniqueness from other commonly employed metrics of nature exposure. The PAD-US-AR presents reliable estimates of parks in the contiguous U.S. that are accessible for outdoor recreation. It has strong associations with home prices, shares of female residents, and shares of older residents. This dataset can accompany other nature exposure metrics in environmental epidemiology and allied research fields. Measurement(s)parkTechnology Type(s)Geographic Information SystemSample Characteristic - EnvironmentCounty • TractSample Characteristic - LocationUnited States Measurement(s) park Technology Type(s) Geographic Information System Sample Characteristic - Environment County • Tract Sample Characteristic - Location United States
... Mapping the distribution of different vegetation types within a city is important for urban landscape planning (Kowe et al., 2021), quantifying ecosystem services (Derkzen et al., 2015;Lafortezza and Giannico, 2019) and assessing environmental justice (Nesbitt et al., 2019). The structural diversity of urban tree plantation (i.e. ...
Mapping urban vegetation types is important for urban planning and assessing environmental justice. Nowadays, despite data cubes projects are providing Analysis Ready Data to facilitate time-series analysis, we did not found studies employing these data for improving urban vegetation mapping. By relying solely on open data and software, this work proposes and evaluates the integration of time-series data cubes in a hybrid image classification method to map the intra-urban space, differentiating Tree cover and Herb-shrub. The urban area of Goiânia, Goiás, Brazil, is the study area. The hybrid method combined object-based classification of a pan-sharpened CBERS-4A WPM image (spatial resolution of 2 m) with the pixel-based classification of Sentinel-2 MSI time-series data cubes (10 m). Both approaches used the Random Forest algorithm. Objects from the CBERS-4A segmentation composed the spatial unit of analysis and the class assignment depended on the Sentinel-2 time-series urban land cover probabilities. Based on both Maps probabilities, Shannon entropy was calculated to attribute the final urban land cover to the objects. Urban land cover probabilities presented similar spatial distribution patterns for both classification approaches. Regarding the thematic maps, the Herb-shrub cover area was 35% higher in Sentinel-2 time-series classification than in GEOBIA classification, but Tree cover was 21% lower. In general, 75% of the study area was equally classified by the initial approaches. However, for 9% of the remaining area, the hybrid classification improved vegetation classes accuracies by 35%, contributing to the vegetation covers identification. Thus, this study contributes to methodological procedures for urban land cover study and demonstrates that hybrid maps based on open data are effective to reduce classification mistakes, allowing more accurate monitoring, planning, and designing of different urban vegetation types. Future research efforts should focus on scale compatibility between data of different spatial resolutions and expand the use of data cubes to integrate time-series information into the GEOBIA classification.
... Numerous studies have employed minimum distance/travel time or gravity models to calculate park-based GS accessibility values and distribution equity Dai, 2011;Liu et al. 2021;Sharifi et al. 2021). Moreover, many studies have focused on the availability of urban vegetation in socioeconomically disadvantaged areas by evaluating remote sensing metrics derived from satellite imagery, such as the normalized difference vegetation index (NDVI) and the proportion of green land use/land cover (Apparicio et al. 2012;Kabisch and Haase, 2014;Nesbitt et al. 2019). Several studies have also considered urban park quality when searching for correlations among vulnerable groups Hughey et al. 2016;Rigolon et al. 2018). ...
Substantial studies have revealed that exposure to green spaces (GSs) yields a variety of health benefits. However, daily GS exposure scenarios are multidimensional, and relevant analyses require a comprehensive framework that assesses GS exposure from overhead- to eye-level perspectives, focusing on GS attributes from quantity and proximity to quality. Moreover, GSs are often unevenly distributed across cities, resulting in green distribution injustice. To this end, this study aimed to systematically evaluate multiple GS exposures considering two-dimensional (2D) spatial exposures (i.e., quantity-based availability, distance-based accessibility, and quality-based attractiveness) and three-dimensional (3D) visual exposures (quantity-based street GS visibility and quality-based street GS perceivability). It then examined the inequalities in GS exposure among socioeconomically disadvantaged groups. Housing prices were employed as proxies for socioeconomic status. Local indicators of spatial association(LISA) were employed to examine the existence of bivariate statistically significant spatial clusters of housing prices and multiple GS exposure. Furthermore, the spatial lag regression model was used to determine inequities in GS exposure among urban residents living in communities with different housing prices. The Nanjing metropolitan area, one of the most densely populated cities in China, was selected as the study case. Residential exposure to GS was comprehensively assessed using a 15-min walkable zone lens. The results suggest that: 1) the spatial cluster of ‘low GS exposure – low housing price’ occupied the largest proportion; 2) all five types of GS exposure were positively associated with housing prices, indicating that the affluent groups are more likely to have access to various GSs; and 3) GS exposure inequalities are more pronounced in measurements of quality(and proximity) than quantity in both spatial and visual exposure metrics. These findings can inform the development of environmental planning and policy strategies for more effective, efficient, and equitable GS provisions that address health issues and green injustice in rapidly urbanizing cities.
... Furthermore, the finding that trees and buildings are inversely correlated with higher temperature differences matches prior studies (Parket et al., 2021;EPA, 2022b) that point to their role in reducing surface and air temperature through shading. According to the temperature analysis, residents in the Maryvale neighborhood, who are among Arizona's most vulnerable populations, are exposed to more heat in the absence of adequate urban vegetation and mitigation strategies, a finding that adds to the literature on disproportionate heat exposure experienced by underrepresented groups (Nesbitt et al., 2019;Hsu et al., 2021). Furthermore, the findings suggest that the temporal and spatial variation detected by mobile sensors does not occur randomly due to instrument noise, since the built environment partially explains some of this variability. ...
Heat and air pollution persist as major public health hazards in urban environments. Yet there are gaps in the quality of information about the hazards as conditions tend to be informed by limited stationary sensors providing information at large geographic scales. Here we present the results of a study that took place in Phoenix, Arizona, to assess the efficacy of low-cost mobile sensors on public transportation vehicles to monitor fine-scale on-road heat and PM 10 concentrations. The goal of the study is to uncover the spatial and temporal variations of excessive heat and air pollution experienced by transit commuters, bicyclists, and pedestrians. The results show that the sensors on the buses complement the readings from stationary sensors and low-cost mobile sensors are effective for gaining fine-grained heat and air quality readings at different locations, thereby creating new insights into pockets of heat and air pollution that should be targeted for intervention.
... We argue that this is the proper planning compromise, as large UGS are difficult to fit within developing cities. However, the distribution of SPUGS and their occurrence throughout cities have proven to be unbalanced, predominantly benefitting affluent communities, and highlighting an environmental justice issue (Wolch et al., 2014;Nesbitt et al., 2019). The presence of large UGS can mitigate exposure to various illnesses in cities, but these types of urban green features are less prevalent in poorer areas (Mitchell et al., 2011). ...
While major urban areas are expanding, becoming more crowded, vegetated lands areshrinking. Built-up densification limits the planning of large urban green spaces,depriving urban dwellers of the benefits provided by such structures. In this context,small public urban green spaces (SPUGS) become of high value for urban landscapes,and their distribution throughout the city should aim to compensate the lack of largergreen areas. The driving forces of SPUGS distribution may be linked to the urbanfunctions they are usually paired with.The current study aimed to determine which are the urban functions that benefit ofhigher amounts of SPUGS in their proximities and to map the distribution and densityof SPUGS within Bucharest, helping us expose the green deprived communities.Results revealed that multi-dwelling residential areas are the ones with higher share ofSPUGS within walking distance. Nevertheless, analysis on SPUGS deprivation withinthe city showed that communist planned residential neighbourhoods are greener thanthe ones developed in the past three decades. Healthcare and commercial functionswithin the city recorded smaller shares of SPUGS in their proximity, highlighting thatvulnerable groups (such as ill people) are exposed to less vegetation, and that publicplanning documents are not encouraging developers to allocate more land for greenfeature development.These results are relevant for projecting the quality of outdoor environmentsthroughout Romania’s capital and for assessing potential future managementchallenges. The outcomes of this research provide local policy makers and plannerswith the vulnerable areas in which immediate action for expanding the greeninfrastructures should take place. At the same time, the methodological approachdescribed in the study proved to be efficient in assessing the distribution of SPUGSthroughout the city and the determinants of this distribution. It can be easily replicatedin other cities by scholars and planners.
... Artificially plant trees to increase vegetation proportion [62] Turn previously barren or discarded lands into human-made parks ...
Rapid urbanization has threatened sustainable urban development in many cities across the globe, causing green space loss and vegetation cover degradation which reduce carbon sequestration. Optimal land management practices (LMPs) in an urban context are known as ways capable of promoting urban vegetation growth and contributing to carbon sequestration. Due to variations of physical, biological, and social structures in urban areas, policymakers often lack relevant information to decide and implement site-specific LMPs. Here we try to extract the areas in need of the optimal LMPs, identify location-dependent optimal LMPs, and assess how much more carbon can be captured by applying a combination of segmenting homogeneous urban environments and neighborhood-based analysis. As one of the most developed cities in China, the greater Guangzhou area (GGA) was selected as a case study. We found that the carbon uptake from the urban vegetation in GGA could be improved on average by 130 gC m−2 yr−1 in flux (or 1.3 TgC yr−1 in total) with optimal LMPs, equivalent to a ~30% increase considering the current level of 662 gC m−2 yr−1 in flux (4.4 TgC yr−1 in total). The carbon uptake potential was found to differ considerably across locations and among different ecosystem types, highlighting spatially varied priorities for implementing optimal LMPs over the space. This study reveals the usefulness of the model in assessing carbon uptake potential from optimal LMPs and emphasizes that future urban planning may consider the importance of optimal LMPs in enhancing vegetation carbon uptake in urban planning.
... These methods can identify potential ecological sources and dispersal corridors of the target species (Kong et al. 2010;Wang and Liu 2019), and can also provide biodiversity conservation guidelines via multiple scenario analysis (Zhang et al. 2019;Ayram et al. 2016;Dai et al. 2017;Selim and Demir 2019). Spatial accessibility, a general evaluation of recreational service, indicates the social equity of UGSs exposure to different resident groups (Rigolon 2016;Van Herzele and Wiedemann 2003;Ekkel and de Vries 2017;Rigolon, Browning, and Jennings 2018;Nesbitt et al. 2019). The promotion of spatial accessibility of UGSs will also benefit human health, primarily for stress reduction and attention recovery in mental health, as well as risk reduction of chronic diseases and human microbiome enrichment in physical health (Zhang et al. 2022). ...
Urban Green Spaces (UGSs) can provide social and ecological benefits, and the coordination of these two functions will largely advance human-nature harmony in cities. As such, we proposed a comprehensive framework to evaluate UGSs multifunctionality, i.e. the coupling coordination relationship of ecological connectivity and spatial accessibility of UGSs. Wuhan City in Central China was taken as a case study, and multiple ecosystem service values of green space patches and the disordered use of UGSs multifunctionality were explored. The results demonstrated low-level coupling coordination of UGSs multifunctionality in Wuhan. More than 70% of UGSs were imbalanced, 27.91% of which featured small sizes, low connectivity and accessibility. We suggest that planners should optimize UGSs arrangement to improve species reachability, especially for species with dispersal distance less than 4 km, and to create 15-minute community life circles for residents at the same time. Our findings are expected to support the promotion of UGSs multifunctionality and the balance of urban development and habitat conservation.
... | Uberlândia, MG | v.34 | e64675 | 2022 |ISSN 1982-4513 parâmetros deTar e Uar não apresentaram outliers, enquanto a concentração de CO2 apresentaramalterações, podendo estar associadas ao pico de fluxo de automóveis, vento e/ou agricultura e outras interferências não mapiáveis na região, assim, havendo a necessidade de exclusão conforme o método aplicado(MARTINS, 2014). Para a análise de dados, optou-se pela utilização do coeficiente de correlação de Spearman para compreender se há ou não correlação entre o comportamento dos parâmetros estudados e a distância da APP, possibilitando, assim, interpretações e análises mais robustas sobre a região em estudo(NESBITT, 2019; BRINDLEY et al., 2019). Destaca-se que se trata de um coeficiente nãoparamétrico, adequado para a aplicação em análise, uma vez que é amplamente utilizado para funções monótonas (preservação da ordemcrescente ou decrescente).Na espacialização dos resultados foi utilizado o método de Inverse Distance Weighting (IDW), sendo desenvolvido dentro de sistema de informações geográficas (SIG), o qual foi escolhido em decorrência da distribuição dos pontos não serem aleatórias e posicionados de forma retilínea devido a acessibilidade da região implementação de modelos robustos como a krigagem. ...
The urban environment is often responsible for negative impacts on the climate and environmental comfort, due to the common climatic interference in highly built and waterproofed environments. One of the ways of mitigating negative environmental and microclimate impacts is the use of green areas in the urban environment. Thus, aiming at the analysis of environmental quality parameters of urban regions, it is essential to monitor the influence of green areas on different meteorological variables. In this sense, the use of information acquisition instruments and methodologies can positively contribute to this analysis, which can support decision-making related to urban planning. Thus, this work aims to develop a sensor network with sensor nodes to assess meteorological variables in urban green areas, aiming to analyze and discuss the influence of green areas on the behavior of CO¬2 concentration, temperature and air relative humidity parameters in an urban environment. The proposed and developed sensor nodes enabled the adequate collection of these variables and, based on the results obtained, it was possible to observe that the green area (permanent preservation area -PPA) contributed positively to these variables in the portion of the study area located in Campinas (SP), presenting lower temperature and CO2 concentration and increased air humidity. However, for the portion of Paulínia (SP), it was possible to observe little influence from the PPA. Influences on these variables, exerted by rural areas and parks, were also identified, contributing to the reduction of meteorological parameters, but different interactions were identified with the CO2 concentration, which may present a possible increase or assist in the reduction of CO2 in the air.
... UV has complex spatial structures, with some having similar spectral properties (Abdollahi and Pradhan, 2021). The distribution of UV is fragmented and heterogeneous, influenced by human activities and urban planning (Nesbitt et al., 2019). The heterogeneity of its horizontal structure can be investigated with additional data sources. ...
Urban vegetation (UV) and its carbon storage capacity are critical for terrestrial carbon cycling and global sustainable development goals (SDGs). With complex spatial distribution, composition and ecological functions, UV is essential for global carbon cycling and climate change. Therefore, improving UV carbon storage capacity modeling is a research hotspot that deserves extensive investigation. However, the uniqueness of UV lead to great challenges in carbon storage modeling, including (1) limitations in data and algorithms due to complex and sensitive urban environments; (2) the severe scarcity of in-city field observation data (e.g., EC towers and field surveys); (3) difficulty in parameter inversion (e.g., canopy height, LAI, etc.); (4) poor transferability when migrating estimation models from natural vegetation to urban scenarios. The progress in carbon storage modeling in urban settings is reviewed, with detailed discussions on carbon storage modeling methods and major challenges. We then propose strategies to overcome existing challenges, including (1) implementing novel and improved remote sensing (RS) techniques (e.g., hyper-spectral, LiDAR, carbon satellites, etc.) to obtain enhanced structural and functional information on UV; (2) improving critical nodes of the earth observation sensor network, especially the distribution of EC towers in urban settings; (3) leveraging "Model-Data Fusion" technology by integrating big earth data with carbon estimation models to reduce the uncertainty in UV carbon storage estimations. This review provides new insights for modeling UV carbon storage and is expected to help the research community to achieve a better understanding of UV towards carbon neutrality.
... Distributive justice, i.e. the fairness in the distribution of environmental "goods" and "harms", is possibly the most widely addressed EJ dimension that undercovers the negative associations between particular social variables and the distribution of environmental assets in terms of their access, allocation, quality and quantity (Brooks et al., 2016;Landry and Chakraborty, 2009;Nesbitt et al., 2019). ...
Environmental justice (EJ) addresses the unequal distribution of environmental goods and harms and promotes people's right to be involved in environmental decision-making. In recent years, EJ considerations have expanded to the use of Nature-based solutions (NbS) in urban areas, mainly how their planning and implementation can impact human well-being and social justice. However, what constitutes a just solution and how the concept is treated in the literature can take many forms. This study reviews how EJ is conceptualised and analysed in urban NbS research and documents the potential outcomes of diverse interventions. We developed a conceptual framework for the review process, focusing on the EJ definitions transferable to NbS research. We then conducted a systematic review of 152 articles published between 2000 and 2021. Selected articles addressed urban NbS from the recognitional, procedural and distributional interpretations of justice. Publication trends, methods, and demographic variables were recorded for each article. Furthermore, we focused on the means for assessing EJ in empirical terms, such as the framing of justice-related challenges, assessment indicators , and the reported justice outcomes. Findings demonstrate the dominance of research themes, the skewness towards the distributive dimension of justice, and a large variety of metrics and indicators used to assess EJ implications. Our results also show that EJ outcomes have mostly been reported to be mixed or negative. The results are used to identify research gaps and issues that need to be addressed to enhance EJ effects in urban NbS.
... Parks can improve health outcomes for people living near them [134]. There is a strong correspondence between urban green space distribution and wealth and education in most US cities [135]. Children are especially vulnerable to the consequences of a deficit in their exposure to natural settings, which can include both cognitive developmental concerns and obesity, the latter leading to long-term increases in "coronary heart disease, hypertension, Type 2 diabetes, stroke, sleep apnea, respiratory problems, and some cancers" [90] but on the beneficial side, "The positive effects of nature exposure include improved cognitive functioning (including increased concentration, greater attention capacities, and higher academic performance), better motor coordination, reduced stress levels, increased social interaction with adults and other children, and improved social skills." ...
This article describes two contesting paradigms of urban planning employed successively in Portland, Oregon; (1) urban planning typical of the US in the first half of the 20th Century that was focused on traffic and infrastructure, and (2) progressive urban planning focused on neighborhood livability and connections. It gives a history of their implementation in Portland, focusing on issues of racial and socioeconomic justice in the Albina neighborhood. Recent knowledge about air pollution's impacts on human health, and infant and childhood development, are integrated into the discussion of urban planning. It describes racially and socioeconomically disproportionate access to urban green spaces, with the corresponding health implications. It also describes attempts to mitigate such health implications, sometimes resulting in "green gentrification" and displacement. The article asks if the results of the two paradigms of urban planning were objectively different from one another in terms of impacts on minority and disadvantaged communities. Future urban planning , and the need for human health concerns becoming central, are discussed.
... With the growing recognition of the benefits provided by green spaces, more recent EJ indicators and tools have focused on measuring accessibility levels to urban green spaces and evidence the disparities faced by traditionally disadvantaged groups (Nesbitt et al., 2019). Some of these studies have also explored these concerns from age, gender or disability perspectives, highlighting the cultural and power relations that make these groups less capable of accessing urban green spaces (Bendlin, 2014;Guo et al., 2019;Kosanic et al., 2022). ...
Environmental justice (EJ) raises concerns about just allocating environmental harms and goods. It has been mainly analysed from a distributive lens through indicators and screening tools that have underlined communities' proximity to pollution and risk sources. However, for urban areas, existing gaps relate to the need for more comprehensive assessments of green space benefits distribution (e.g., flood mitigation, air pollution control and recreation, etc.) as well as aligning EJ indicators to local planning and policy efforts for simultaneously addressing planning issues and reinforce the evaluation of existing unjust realities.
To address these issues, we developed a composite distributive environmental justice index (DEJI) structured into three sub-indices that reflect locally relevant patterns of environmental risks, disadvantaged communities, and the provision of green space benefits. The construction of this index also relies on a qualitative content analysis of planning and policy documents to contextualise EJ priorities relevant to the planning administration, and a detailed methodological rationale for composite indicator building. Applying the DEJI in Las Palmas de Gran Canaria (Spain) at the census tract level, we identified a complex city-wide pattern of distributive injustices driven by the historical segregation patterns of insular contexts. Based on our results, we discuss how using the DEJI could help planning and policymakers reach specific goals, including those related to enhancing greening interventions in urban areas. Moreover, we argue that EJ composite indicators are needed to support environmentally just trajectories in cities with realities and planning patterns different from those found in mainland territories.
... Furthermore, in another study (He et al., 2020), the authors shows that economic growth can positively impact the green area level, but vegetation development does not necessarily imply economic growth. Researchers also studied the possible relationship between vegetation areas and people's education and income (Nesbitt et al., 2019). The spatiotemporal changes of these green regions, focusing in a particular ecosystem, such as in mountains, is also the topic of several studies, such as in (Bian et al., 2020). ...
The interaction between cities and their respective green regions corresponds to an interesting issue that has received growing attention over the last decades. These relationships have multiple natures, ranging from providing habitat for animal life to temperature and humidity dynamics. Several methods based on area, size, shape, and distance have been considered in the literature. Given that several important contributions of green regions to urban areas involve temperature, humidity, and gases exchanges, which are intrinsically related to physical diffusion, it becomes particularly interesting to simulate the diffusion of green effects over urban areas as a means of better understanding the respective influences. The present work reports a related approach. Once the green regions of a given city are automatically identified by semantic segmentation and have eventual artifacts eliminated, successive convolutions are applied as a means to obtain the unfolding of the diffusion of the green effects along time. As illustrated, the diffusion dynamics is intrinsically interesting because it can be strongly affected by the spatial distribution of the green mass. In particular, we observed that smaller green regions could substantially contribute to the diffusion. The reported approach has been illustrated with respect to the Brazilian city of Ribeirão Preto, whose small- and medium-sized green regions were found to complement in an effective manner the diffusion of the green effects as inferred from the performed simulations under specific parameter settings.
... Access to urban green infrastructure is typically unequal across urban landscapes, varying with social and economic status of urban areas 8 . This is particularly prominent in several US cities, which show that good access to urban vegetation is strongly correlated with higher education and income and negatively associated with being a person of colour 9 . Also, across eight European countries, evidence shows older age groups and people of lower socio-economic status visit green space less frequently 10 . ...
Recent empirical research has confirmed the importance of green infrastructure and outdoor recreation to urban people’s well-being during the COVID-19 pandemic. However, only a few studies provide cross-city analyses. We analyse outdoor recreation behaviour across four Nordic cities ranging from metropolitan areas to a middle-sized city. We collected map-based survey data from residents ( n = 469–4992) in spring 2020 and spatially analyse green infrastructure near mapped outdoor recreation sites and respondents’ places of residence. Our statistical examination reveals how the interplay among access to green infrastructure across cities and at respondents’ residential location, together with respondents’ socio-demographic profiles and lockdown policies or pandemic restrictions, affects outdoor recreation behaviour. The results highlight that for pandemic resilience, the history of Nordic spatial planning is important. To support well-being in exceptional situations as well as in the long term, green infrastructure planning should prioritise nature wedges in and close to cities and support small-scale green infrastructure.
Funding and financing challenges remain a persistent barrier to implementing nature‐based solutions that enhance ecosystem services, facilitate adaptation to climate change, and combat environmental stressors in cities. In the absence of adequate public financial resources, private funds are often expected to fill the gap. But market‐driven, nature‐based solutions can contribute to an inequitable distribution of urban ecosystem services by focusing on net benefits provided by nature. To help foster sustainable development and ensure that nature‐based solutions reach diverse and historically marginalized populations and communities, this scoping review explores the ecosystem services provided by nature‐based solutions and the payment mechanisms that produce and maintain them, focusing on literature on the United States. Findings suggest that the net benefits provided by nature‐based solutions and the available payment mechanisms vary based on the solution utilized (e.g., urban trees, parks, community gardens). Further, the distribution of benefits from nature‐based solutions is influenced by local historical, cultural, political, economic, and environmental contexts, the voices included in decision‐making, and the payment mechanisms used. Inspired by social equity principles, we present a framework for ecosystem service provision that is sensitive to market‐driven funding, financing, and partnerships. Practitioners can use this framework to assess whether payment schemes work in tandem with place (the local context) and process (governance and planning approaches) to ameliorate or exacerbate disparities in nature‐based solutions and the benefits they provide to people.
More than half of the human population lives in cities and therefore predominantly experience nature in urban greenspace, an important contributor to wellbeing. As the world faces a pandemic which threatens the physical and mental health of billions of people, it is crucial to understand that all have the possibility to access nature exposure to alleviate some of these challenges. Here, for the first time, we integrate data from Facebook, Twitter, and Google Search users to show that people looked for greenspace during COVID-19 mobility restrictions but may not have always managed to reach it. We used a longitudinal approach, replicated in three European cities, to assess whether people spent more time in locations with more greenspace, and whether this change in urban density remained for the whole pandemic, pre-vaccine, period. We coupled this human density study with a longitudinal study of web search patterns for Parks and online discussion about urban greenspace. People searched for Parks near them more during the pandemic, particularly when they were allowed to visit them. They discussed in positive terms greenspace particularly more at the start of the pandemic. People spent more time in areas with greenspace when they could and that depended on the level of multiple deprivation of their neighbourhood. Importantly, while people sought greenspace throughout the first 20 months of the pandemic, this preference intensified through the waves of lockdown. Living in an affluent area conferred a greenspace advantage in London and Paris but we find that in Berlin greenspace in more deprived neighbourhoods were used more. Overall, urban greenspace occupied a greater place in people's lives during the pandemic. Whether people could realise greenspace access depended on the deprivation level of the neighbourhood. Public greenspace access should be integrated in national indices of deprivation given its importance for wellbeing.
Lacustrine blue spaces provide benefits to the urbanites and wildlife habitat. Their availability varies depending on the city in which they are established and intra-urban social interactions. We analyzed the presence, distribution, and size of lentic water bodies in Mexico’s 145 most populated cities. We searched for patterns in their distribution concerning demographic, socioeconomic, and geographic data, aiming to understand their socio-ecological interactions in cities. We digitized lacustrine spaces to obtain their number per city, total surface, area of blue space per inhabitant, and surface as a percentage of the city’s total area. We tested for relationships between their number and surface and city population, hydrological regions, and urban marginalization index through linear and generalized linear models. We delimited 1834 lacustrine blue spaces, finding almost two-thirds of them artificial. Their presence and surface in Mexican cities were generally low, except for hydrological regions close to the Gulf of Mexico. Their number and surface decreased as the urban marginalization index increased. The lack of equitable provision of lacustrine space at the national level has implications for urban planning and land management. Blue spaces should maximize their ecosystem services’ provision for the whole society to promote cities’ sustainability and resilience.
Urban Green Spaces (UGSs) provide a wide range of ecosystem services to cities. However, many cities suffer from the uneven spatial distribution of UGSs. This phenomenon can occur not only in cities with growing populations, but also in those with shrinking populations. Today, many cities around the world are continuously shrinking due to population decline. However, there is still a lack of information on urban forms and the distribution of UGSs. Therefore, this study analyzes the relationship between urban form and UGS equity in shrinking cities by mapping and measuring urban form indicators and UGS equity indicators in 147 shrinking cities in seven regions of Japan for the first time. The results show that 1) partial Japanese urban shrinkage affects equitable development of UGSs; 2) cities with compact populations facilitate equitable urban development; 3) the shape and continuity of urban patches affect the distribution of UGSs in shrinking cities in all regions; 4) urban size, centrality, compactness of urban patches, and urban patch fragmentation affect the distribution of UGSs in shrinking cities in local regions. The results of this study can provide city managers with reliable urban development strategies to promote equitable distribution of UGSs in shrinking cities.
Urban green space (UGS) plays a critical role in promoting a sustainable development of urban ecology and improving inhabitants’ well-beings. Equal access to UGS is vital for enjoying the benefits of UGS. However, those non-park green space (NPGS) that is more closely related to inhabitants’ residence are often ignored when investigating inhabitants’ equity of UGS accessibility. In this study, two scenarios with or without considering NPGS were set up to reveal the contribution of NPGS in improving the equity of UGS accessibility. This study was conducted at a block scale in Wuhan, a megacity in central China. Results indicate that the accessibility to UGS is more equally distributed when considering NPGS compared to without considering NGPS and the contribution of NPGS is 79.32%. The Gini coefficients of the scenario without considering NGPS is higher (0.93) while a lower one in the other scenario (0.62). The Lorenz curve and Gini coefficients indicate an improvement of equity of UGS accessibility after considering NPGS. This study highlights the importance of considering the NPGS when improving the equity of UGS accessibility. This is particularly meaningful in megacities where UGS is scarce and more obviously unequal access to UGS may occur.
Environmental justice is the concept that all people have the right to live in a healthy environment, to be protected against environmental hazards, and to participate in decisions affecting their communities. Communities of color and low-income populations live, work and play in environments with disproportionate exposure to hazards associated with allergic disease. This unequal distribution of hazards has contributed to health disparities and is largely the result of systemic racism that promotes segregation of neighborhoods, disinvestment in predominantly racial/ethnic minority neighborhoods, and discriminatory housing, employment and lending practices. The AAAAI Environmental Exposure and Respiratory Health (EERH) Committee and Diversity, Equity and Inclusion (DEI) Committee jointly developed this report to improve allergy/immunology specialists' awareness of environmental injustice, its roots in systemic racism, and its impact on health disparities in allergic disease. We present evidence supporting the relationship between exposure to environmental hazards, particularly at the neighborhood level, and the disproportionately high incidence and poor outcomes from allergic diseases in marginalized populations. Achieving environmental justice requires investment in at-risk communities to increase access to safe housing, clean air and water, employment opportunities, education, nutrition, and healthcare. Through policies that promote environmental justice, we can achieve greater health equity in allergic disease.
Cities are increasingly profiling themselves as active agents within sustainability
transformation. Despite many apparent efforts, discussion on “sustainable
cities” has often focused on narrowly defined problems and ignored the interconnectedness of ecological, social, and economic issues that extend beyond the boundaries of formal city regions. Hence, this paper highlights the need for approaches that take into account the multifaceted nature of urban sustainability. We use planetary urbanism and urban metabolism as conceptual lenses to demonstrate the embeddedness of cities in planetary ecological systems and social structures. We present two examples of urban initiatives, one from strategic level and one from practical urban planning, both highlighting the relevance of planetary urbanisation and urban metabolism. Our examination calls for rethinking prevailing ideas of cities as forerunners of sustainable development and highlights the importance of collaboration in curbing potentially harmful sociospatial divisions.
Amidst the intersecting crises of the COVID-19 pandemic and ongoing police brutality against Black people, jurisdictions across the United States declared racism to be a public health crisis in the summer of 2020. According to the American Public Health Association (APHA), 233 jurisdictions have published such declarations as of January 2022, with 92% of declarations being made at the city or county level. What does it mean to frame racism as a public health crisis? This paper explores and compares theoretical and practical definitions of disasters and crises from the planning field through a review of the literature. The author concludes that racism can be conceptualized as a slow-onset disaster. With the understanding that racism can be understood as a disaster, the author demonstrates the utility of leveraging a disaster recovery framework to drive a comprehensive response to address racism as a public health crisis.
O Objetivo do Desenvolvimento Sustentável 11.7 visa fornecer acesso universal a espaços públicos verdes, o que pode ser alcançado por um sistema bem planejado de áreas verdes (AV). Este estudo buscou, portanto, identificar lacunas na distribuição de AV relacionada a variáveis demográficas e socioeconômicas. Curitiba foi selecionada como área de estudo por ser internacionalmente conhecida por suas 1.182 AV. Dez variáveis sobre população, renda e AV foram calculadas com base em dados espaciais e divididas em 40 bairros agrupados. Foram realizadas análises estatísticas descritivas bem como correlações de Pearson, Spearman e Kendall. Os principais resultados são apresentados em valores mínimos-máximos por bairro (com valor médio entre parênteses): quantidade 12 – 113 (31,07); área média 0,00 – 0,66 km² (0,03); área total 0,02 – 7,87 km² (0,67); quantidade por área do bairro 0,35 – 12,44 AV/km² (3,98); área do bairro ocupada por AV 0,30 – 42,44% (5,03%); população por quantidade de AV 442,17 – 2.789,26 habitantes/AV (1.564,97); e índice de AV 0,65 – 269,56 m²/habitante (16,77). Correlações fortes foram encontradas principalmente para renda per capita entre a quantidade de AV por área do bairro (positiva) e a população por quantidade de AV (inversa). Os resultados mostram grande amplitude e diferenças relevantes entre bairros que podem auxiliar planejadores urbanos.
Given the important role of urban green space (UGS) playing in sustainable cities, UGS has received extensive attention and study. However, most studies were limited to individual cities or regions and yielded inconsistent results due to the use of diverse data sources and methods, and little is known about the inequality in green provision at the global scale. In this study, we compared green provisions and inequality in 1013 cities (built-up areas≥100 km2) around the globe utilizing the indicators of percentage of green area, green exposure, and Gini coefficient. Furthermore, their relation to demographic, geophysical and socioeconomic factors was estimated at the levels of the globe, geographical regions, and income divisions. We found that the large cities in high-income countries enjoy much more adequate and equitable UGS resources than that in low-income countries. In global context, population density is most strongly associated with UGS provision and inequality, while climate influence UGS to a higher extent than human activities in most regions. The interactions with demographic or climatic factors have a relatively significant nonlinear-enhanced effect on UGS. Our findings can provide insights for greening interventions at regional and global scales.
How uneven is the proximity to public amenities like libraries and schools among racial groups, or children and older people? This paper uses a catchment area approach to evaluate walkable proximity to four common public amenities (parks, libraries, schools, and transit stops), looking at four racial categories and a set of variables that one might reasonably expect proximity to be related to (e.g., population density). For each of the 10 largest US cities examined, location quotients for each amenity (libraries, parks, schools, and transit stops) were calculated at three distances (0.25 miles, 0.5 miles, and 1 mile). Across all amenities, the racial group whose LQ had the greatest increase when comparing net median change between distance bands (i.e., between .25 miles and 1 mile) was Black Americans. There were large differences between the location quotient means and medians in non-White racial groups for each amenity, indicating a large amount of skew. In most cities and with most amenities, the difference between mean and median was considerably smaller in White populations, indicating a more normal curve and fewer outliers. Proximity, in other words, seems to be more homogenous in White populations. The LQs were also significantly higher in White populations across cities. Further, in all cities except Los Angeles, Asian populations were generally the most under-represented group for each catchment area around each amenity. The fact that non-White residents predominantly had lower LQs and therefore lower access (with some exceptions, for example, in the case of schools) is a generalized and problematic finding that adds to the body of evidence documenting the spatial injustices that American cities continue to manifest.
Childhood obesity has been a major health concern for decades now, especially in western countries like the United States, and its alarming rate of growth allows it to be considered a pandemic. The factors that contribute to the development of childhood obesity can be categorized on both a macro- and microscopic level, spanning from national attitudes toward food, all the way to individual trauma. This work attempts to condense some of the latest research on factors contributing to childhood obesity in order to construct a more holistic picture of its causes. Some of the topics discussed in this article demographic and cultural consideration as well as family life and genetic predisposition toward obesity. Finally, the article looks at the ways in which the COVID-19 pandemic have affected childhood obesity in the United States ad projections that can be made from the increasing rate of weight gain among children.
Do urban residents experience societal benefits derived from urban forests equitably? We conducted a broad-scale spatial analysis of the relationship between urban greenery and socioeconomic factors in the Portland metropolitan area. The Normalized Difference Vegetation Index was derived from National Agriculture Imagery Program images to map urban vegetation cover, and Outdoor Recreation and Conservation Area data were used to identify green spaces. These measures of urban greenery were correlated with census data to identify socioeconomic factors associated with high levels of green inequity. Population density, house age, income, and race were strongly correlated with vegetation cover. However, the distribution of green spaces showed a much weaker relationship with socioeconomic factors. These results highlight the importance of different measures of access to urban greenery and suggest potential solutions to the problem of urban green inequity. Cities can use our methods to conduct targeted urban forest management to maximize urban forest benefits received by residents.
We argue that existing studies underestimate the degree that racial change leads to residential segregation in post-Civil Rights American neighborhoods. This is because previous studies only measure the presence of racial groups in neighborhoods, not the degree of integration among those groups. As a result, those studies do not detect gradual racial succession that ends in racially segregated neighborhoods. We demonstrate how a new approach based on growth mixture models can be used to identify patterns of racial change that distinguish between durable integration and gradual racial succession. We use this approach to identify common trajectories of neighborhood racial change among Blacks, Whites, Latinos, and Asians from 1970 to 2010 in the New York, Los Angeles, Chicago, and Houston metropolitan areas. We show that many nominally integrated neighborhoods have experienced gradual succession. For Blacks this succession has caused the gradual concentric diusion of the ghetto while Latino and Asian growth has dispersed throughout both cities and suburbs in the metropolitan areas. Durable integration, meanwhile, has come about largely in the suburbs.
Because a large proportion of the urban forest grows on private property, it is necessary to have broad community support for urban forestry. As people from all over the world live in Canadian cities, it was hypothesized that people with different cultural backgrounds would have different perceptions of the urban forest. This hypothesis was tested by (1) researching different landscaping traditions; (2) interviewing members of four different communities; and (3) conducting vegetation inventories. Inventory and interview data provided a consistent picture of the four communities. The British community reacted the most positively to shade trees, they also expressed the greatest willingness to plant shade trees, had the most shade trees per square meter on their properties, and were the only group that liked naturalized parks (hiking paths). The Chinese community showed less yard maintenance than the other communities, and many of the Chinese indicated that they did not want to add trees to their property. The Chinese responded more favorably than the other groups to photographs depicting landscapes free of trees. Italian and Portuguese communities emphasized fruit trees and vegetable gardens, and responded negatively toward shade trees when these were in conflict with their gardens. These cultural differences are largely consistent with the traditional use of trees in British, Mediterranean and Chinese landscaping, and appear to be maintained among North American immigrant populations.
This study examines the distributional equity of urban tree canopy (UTC) cover for Baltimore, MD, Los Angeles, CA, New York, NY, Philadelphia, PA, Raleigh, NC, Sacramento, CA, and Washington, D.C. using high spatial resolution land cover data and census data. Data are analyzed at the Census Block Group levels using Spearman's correlation, ordinary least squares regression (OLS), and a spatial autoregressive model (SAR). Across all cities there is a strong positive correlation between UTC cover and median household income. Negative correlations between race and UTC cover exist in bivariate models for some cities, but they are generally not observed using multivariate regressions that include additional variables on income, education, and housing age. SAR models result in higher r-square values compared to the OLS models across all cities, suggesting that spatial autocorrelation is an important feature of our data. Similarities among cities can be found based on shared characteristics of climate, race/ethnicity, and size. Our findings suggest that a suite of variables, including income, contribute to the distribution of UTC cover. These findings can help target simultaneous strategies for UTC goals and environmental justice concerns.
Several social theories have been proposed to explain the uneven distribution of vegetation in urban res-idential areas: population density, social stratification, lux-ury effect, and ecology of prestige. We evaluate these theories using a combination of demographic and socio-economic predictors of vegetative cover on all residential lands in New York City. We use diverse data sources including the City's property database, time-series demo-graphic and socio-economic data from the US Census, and land cover data from the University of Vermont's Spatial Analysis Lab (SAL). These data are analyzed using a multi-model inferential, spatial econometrics approach. We also examine the distribution of vegetation within distinct mar-ket categories using Claritas' Potential Rating Index for Zipcode Markets (PRIZM TM) database. These categories can be disaggregated, corresponding to the four social theories. We compare the econometric and categorical results for validation. Models associated with ecology of prestige theory are more effective for predicting the distri-bution of vegetation. This suggests that private, residential patterns of vegetation, reflecting the consumption of envi-ronmentally relevant goods and services, are associated with different lifestyles and lifestages. Further, our spatial and temporal analyses suggest that there are significant spatial and temporal dependencies that have theoretical and methodological implications for understanding urban eco-logical systems. These findings may have policy implica-tions. Decision makers may need to consider how to most effectively reach different social groups in terms of mes-sages and messengers in order to advance land management practices and achieve urban sustainability.
Climate change will have unavoidable impacts on urban systems and populations, especially in Asia where many large cities are exposed. Climate adaptation will be essential, and planning for adaptation can be simplified through operationalizing concepts of climate resilience and vulnerability. This article reviews concepts and theories in a range of diverse fields to illustrate how the general notion of urban climate resilience can be developed into an operational framework for planning practitioners. The framework integrates theoretical and empirical knowledge of the factors contributing to resilience with processes for translating those concepts into practice. The framework includes characteristics of urban systems, the agents (people and organizations) that depend on and manage those systems, institutions that link systems and agents, and patterns of exposure to climate change. It operationalizes these concepts through structured and iterative shared learning approaches that allow local planners to define these factors in their own context, in order to develop practical strategies for local action. The viability of the framework is demonstrated through examples from resilience planning activities undertaken in 10 cities across Asia through the Asian Cities Climate Change Resilience Network funded by the Rockefeller Foundation.
North America contains some of the most urbanized landscapes in the world. In the United States (U.S.) and Canada, approximately 80 % of the population is urban, with Mexico slightly less (Kaiser Family Foundation 2013). Population growth combined with economic growth has fueled recent urban land expansion in North America. Between 1970 and 2000, urban land area expanded at a rate of 3.31 % (Seto et al. 2011) creating unique challenges for conserving biodiversity and maintaining regional and local ecosystem services.
The aesthetic, economic, and environmental benefits of urban trees are well recognized. Previous research has focused on understanding
how a variety of social and environmental factors are related to urban vegetation. The aim is often to provide planners with
information that will improve residential neighborhood design, or guide tree planting campaigns encouraging the cultivation
of urban trees. In this paper we examine a broad range of factors we hypothesize are correlated to urban tree canopy heterogeneity
in Salt Lake County, Utah. We use a multi-model inference approach to evaluate the relative contribution of these factors
to observed heterogeneity in urban tree canopy cover, and discuss the implications of our analysis. An important contribution
of this work is an explicit attempt to account for the confounding effect of neighborhood age in understanding the relationship between human and environmental factors, and urban tree canopy. We use regression analysis
with interaction terms to assess the effects of 15 human and environmental variables on tree canopy abundance while holding
neighborhood age constant. We demonstrate that neighborhood age is an influential covariate that affects how the human and
environmental factors relate to the abundance of neighborhood tree canopy. For example, we demonstrate that in new neighborhoods
a positive relationship exists between street density and residential tree canopy, but the relationship diminishes as the
neighborhood ages. We conclude that to better understand the determinants of urban tree canopy in residential areas it is
important to consider both human and environmental factors while accounting for neighborhood age.
For older adults, social integration and the strength of social ties are profoundly important predictors of well-being and longevity. Can the physical environment be designed to promote older adults' social integration with their neighbors? We examined this possibility by testing the relationships between varying amount of exposure to green outdoor common spaces and the strength of ties among neighbors. Results of interviews with 91 older adults (between the ages of 64 and 91 years) from one inner-city neighborhood show that the use of green outdoor common spaces predicted both the strength of neighborhood social ties and sense of community. Although the strength of these relationships were modest, the findings suggest that the characteristics of outdoor common spaces can play a role in the formation and maintenance of social ties among older adult residents of inner-city neighborhoods. The results have implications for designers, managers, and residents of housing developments.
Depending on what is in the view, looking out the window may provide numerous opportunities for restoration. Unlike other restorative opportunities, however, window viewing is more frequent and for brief moments at a time. The setting is also experienced from afar rather than while being in it. A study conducted at six low-rise apartment communities, using a survey with both verbal and visual material, provides considerable support for the premise that having natural elements or settings in the view from the window contributes substantially to residents’ satisfaction with their neighborhood and with diverse aspects of their sense of well-being. Views of built elements, by contrast, affected satisfaction but not well-being. Views of the sky and weather did not have a substantial effect on either outcome. The potential of nature content in the view from home to contribute so significantly to satisfaction and well-being suggests clear action mandates.
This article examines the distribution of parks in Baltimore, Maryland, as an environmental justice issue. In addition to established methods for measuring distribution of and access to parks, we employ a novel park service area approach that uses Thiessen polygons and dasymetric reapportioning of census data to measure potential park congestion as an equity outcome measure. We find that a higher proportion of African Americans have access to parks within walking distance, defined as 400 meters or less, than whites, but whites have access to more acreage of parks within walking distance than blacks. A needs-based assessment shows that areas with the highest need have the best access to parks but also have access to less acreage of parks compared to low-need areas. Park service areas that are predominantly black have higher park congestion than areas that are predominantly white, although differences are less apparent at the city level than at the metropolitan level. Following Iris Young and others, we argue that conceptions of justice must move beyond distributive justice and address the social and institutional mechanisms that generate inequities. For Baltimore, we examine how segregation ordinances, racial covenants, improvement associations, the Home Owners Loan Corporation, and the Parks and Recreation Board created separate black spaces historically underserved with parks. These mechanisms ultimately fueled middle-class flight and suburbanization and black inheritance of much of Baltimore's space, including its parks. If justice demands just distribution justly achieved, the present-day pattern of parks in Baltimore should be interpreted as environmental injustice.
Objective:
We examined the distribution of heat risk-related land cover (HRRLC) characteristics across racial/ethnic groups and degrees of residential segregation.
Methods:
Block group-level tree canopy and impervious surface estimates were derived from the 2001 National Land Cover Dataset for densely populated urban areas of the United States and Puerto Rico, and linked to demographic characteristics from the 2000 Census. Racial/ethnic groups in a given block group were considered to live in HRRLC if at least half their population experienced the absence of tree canopy and at least half of the ground was covered by impervious surface (roofs, driveways, sidewalks, roads). Residential segregation was characterized for metropolitan areas in the United States and Puerto Rico using the multigroup dissimilarity index.
Results:
After adjustment for ecoregion and precipitation, holding segregation level constant, non-Hispanic blacks were 52% more likely (95% CI: 37%, 69%), non-Hispanic Asians 32% more likely (95% CI: 18%, 47%), and Hispanics 21% more likely (95% CI: 8%, 35%) to live in HRRLC conditions compared with non-Hispanic whites. Within each racial/ethnic group, HRRLC conditions increased with increasing degrees of metropolitan area-level segregation. Further adjustment for home ownership and poverty did not substantially alter these results, but adjustment for population density and metropolitan area population attenuated the segregation effects, suggesting a mediating or confounding role.
Conclusions:
Land cover was associated with segregation within each racial/ethnic group, which may be explained partly by the concentration of racial/ethnic minorities into densely populated neighborhoods within larger, more segregated cities. In anticipation of greater frequency and duration of extreme heat events, climate change adaptation strategies, such as planting trees in urban areas, should explicitly incorporate an environmental justice framework that addresses racial/ethnic disparities in HRRLC.
Urban particulate air pollution is a serious health issue. Trees within cities can remove fine particles from the atmosphere and consequently improve air quality and human health. Tree effects on PM2.5 concentrations and human health are modeled for 10 U.S. cities. The total amount of PM2.5 removed annually by trees varied from 4.7 tonnes in Syracuse to 64.5 tonnes in Atlanta, with annual values varying from $1.1 million in Syracuse to $60.1 million in New York City. Most of these values were from the effects of reducing human mortality. Mortality reductions were typically around 1 person yr(-1) per city, but were as high as 7.6 people yr(-1) in New York City. Average annual percent air quality improvement ranged between 0.05% in San Francisco and 0.24% in Atlanta. Understanding the impact of urban trees on air quality can lead to improved urban forest management strategies to sustain human health in cities.
Kyoto is an old city blessed with beautiful natural and cultural landscapes. With the long history of the various events and
responses to them, Kyoto is expected to offer some insight into how to create a sustainable city with resilience relevant
to its historical inheritances and biodiversity. In this paper, we attempt to describe some concepts of developments and responses
that could mitigate the negative impact of urbanization on its biodiversity and ecosystem services. (1) Modern city planning
considering natural amenities as well as old Feng-shui geomancy theory could conserve the surrounding mountains. Down-zoning
and vistaed view preservation are examples. (2) Inside the city areas, the theory of island biogeography is applicable for
biodiversity planning, and the size of the isolated greenery is the most important factor for species richness of all taxonomic
groups. However, a single large patch is not always sufficient to conserve as many species as possible. Moreover, the heterogeneity
of the environment, which is formed by its design and management, plays an important role in species richness. Japanese gardens
and the created wildlife habitat park are good solutions for biodiversity. (3) The nature of rivers and wetland systems has
been severely degraded in the urbanization process. However, the excellent Katsura detached palace garden and Oguraike wetland
system, which were one-time national monuments with high biodiversity, suggest a smart adaptation to the increasing risk of
flooding by climate change: “Do you Kyoto”?
KeywordsKyoto–Sustainability–Low-carbon society–Biodiversity–Biodiversity-conscious city–Smart adaptation
Our understanding of the dynamics of urban ecosystems can be enhanced by examining the multidimensional social characteristics
of households. To this end, we investigated the relative significance of three social theories of household structure—population,
lifestyle behavior, and social stratification—to the distribution of vegetation cover in Baltimore, Maryland, USA. Our ability
to assess the relative significance of these theories depended on fine-scale social and biophysical data. We distinguished
among vegetation in three areas hypothesized to be differentially linked to these social theories: riparian areas, private
lands, and public rights-of-way (PROWs). Using a multimodel inferential approach, we found that variation of vegetation cover
in riparian areas was not explained by any of the three theories and that lifestyle behavior was the best predictor of vegetation
cover on private lands. Surprisingly, lifestyle behavior was also the best predictor of vegetation cover in PROWs. The inclusion
of a quadratic term for housing age significantly improved the models. Based on these research results, we question the exclusive
use of income and education as the standard variables to explain variations in vegetation cover in urban ecological systems.
We further suggest that the management of urban vegetation can be improved by developing environmental marketing strategies
that address the underlying household motivations for and participation in local land management.
Poor mental health is a major issue worldwide and causality is complex. For diseases with multifactorial background synergistic effects of person- and place- factors can potentially be preventive. Nature is suggested as one such positive place-factor. In this cohort study we tested the effect of defined green qualities (Serene, Space, Wild, Culture, Lush) in the environment at baseline on mental health at follow-up. We also studied interaction effects on mental health of those place factors and varied person factors (financial stress, living conditions, and physical activity).
Data on person factors were extracted from a longitudinal (years 1999/2000 and 2005) population health survey (n = 24945). The participants were geocoded and linked to data on green qualities from landscape assessments, and stored in the Geographical Information System (GIS). Crude odds ratios (OR) and 95% confidence intervals (CI) were calculated, and multivariate logistic analyses were performed.
Mental health was not affected by access to the chosen green qualities, neither in terms of amount nor in terms of any specific quality. However, we found a reduced risk for poor mental health at follow-up among women, through a significant interaction effect between physical activity and access to the qualities Serene or Space. For men the tendencies were similar, though not significant. Regarding the other three green qualities, as well as amount of qualities, no statistically certain synergistic effects were found. Likewise, no significant synergies were detected between green qualities and the other person-factors. Only advanced exercise significantly reduced the risk for poor mental health among women, but not for men, compared to physical inactivity.
The results do not directly support the hypothesis of a preventive mental health effect by access to the green qualities. However, the additive effect of serene nature to physical activity contributed to better mental health at follow-up. This tendency was equal for both sexes, but statistically significant only for women.Objective landscape assessments may be important in detangling geographic determinants of health. This study stresses the importance of considering interaction effects when dealing with disorders of multifactorial background.
This paper is a review of research in Chicago that linked analyses of vegetation structure with forest functions and values. During 1991, the regions trees removed an estimated 5575 metric tons of air pollutants, providing air cleansing worth 9.2 million. Each year they sequester an estimated 315 800 metric tons of carbon. Increasing tree cover 10% or planting about three trees per building lot saves annual heating and cooling costs by an estimated 50 to 90 per dwelling unit because of increased shade, lower summertime air temperatures, and reduced neighborhood wind speeds once the trees mature. The net present value of the services trees provide is estimated as 402 per planted tree. The present value of long-term benefits is more than twice the present value of costs.
In this paper, we summarize findings from a series of interrelated studies that examine an urban greenway, the 150 mile Chicago River corridor in Chicago, USA, from multiple perspectives, stakeholder viewpoints, and methodological techniques. Six interdependent “human dimensions” of greenways are identified in the studies: cleanliness, naturalness, aesthetics, safety, access, and appropriateness of development. Together, these dimensions form a core set of concerns relating to how people perceive and use the greenway for recreation and related experiences. While these dimensions show good consistency across our studies and are supported by the literature in the field, the quantitative and qualitative methods used also uncovered a rich variation in how the dimensions are construed by different stakeholder groups and along different reaches of the corridor. Using local demonstration projects from along the corridor, we illustrate how principles inherent in each dimension can be applied to improve the success of greenways through design, management, or programming. We conclude by discussing the applicability of these dimensions and methods of study to understand other urban and non-urban greenways, and suggest how the findings from such studies can be used to inform greenways planning, policy, and management.
A modeling study using hourly meteorological and pollution concentration data from across the coterminous United States demonstrates that urban trees remove large amounts of air pollution that consequently improve urban air quality. Pollution removal (O3, PM10, NO2, SO2, CO) varied among cities with total annual air pollution removal by US urban trees estimated at 711,000 metric tons ($3.8 billion value). Pollution removal is only one of various ways that urban trees affect air quality. Integrated studies of tree effects on air pollution reveal that management of urban tree canopy cover could be a viable strategy to improve air quality and help meet clean air standards.
While urban disamenities and pollution sources have received considerable attention in environmental justice research, few studies have examined sociospatial inequities associated with the distribution of desirable land uses. In this paper we focus on addressing this limitation by investigating the environmental equity implications of street trees—an important publicly financed amenity that provides several direct and indirect benefits to urban residents. The specific objective was to determine if the spatial distribution of public right-of-way trees is equitable with respect to race and ethnicity, income, and housing tenure in the city of Tampa, Florida, USA. We seek to extend research on equity analysis of urban amenities through several methodological innovations, including: (a) accounting for the heterogeneity of urban land use; (b) utilizing high-resolution remote sensing techniques to quantify parcel-specific tree cover; and (c) using multivariate regression models that control for spatial dependence within the data. The results support the inequity hypothesis by indicating a significantly lower proportion of tree cover on public right-of-way in neighborhoods containing a higher proportion of African-Americans, low-income residents, and renters. These findings have important implications for local public investment and policy strategies.
Urban vegetation provides a suite of ecosystem services to urban residents, from regulating microclimate to supporting good physical health. As more and more people make cities their home, urban vegetation is becoming a key part of urban residents’ well-being. Urban green equity is a central aspect of the distribution of and governance over urban vegetation and its associated ecosystem services. While issues of equity in urban forestry are of clear importance in a just society, it is unclear how the concept should be defined and analyzed. To begin to address this gap, this dissertation 1) examines the theoretical dimensions of urban green equity from multiple perspectives, 2) explores how urban forestry practitioners understand and use the concept of urban green equity in three case-study cities in the United States (US), and 3) conducts a spatial analysis of distributional green equity across 10 urbanized areas in the US. The research found 1) that there are multiple, related dimensions of urban green equity centred around two principle dimensions: distribution of urban vegetation and recognition of stakeholders in urban vegetation decision making, 2) that urban forestry practitioners collectively have a nuanced and complex understanding of urban green equity and tend to focus on distributional equity in their definitions and use of the concept, and 3) that distributional green inequity exists across multiple urbanized areas in the US, education and income are the factors most strongly predictive of the spatial distribution of urban vegetation, and public parks tend to be more equitably distributed than mixed and woody vegetation in cities. It is my hope that these results, and the methodological and conceptual approaches and frameworks provided by this research will be used to advance the rigorous study of urban green equity and improve urban green equity in practice in cities around the world.
There is ample evidence that urban trees benefit the physical, mental, and social health of urban residents. The environmental justice hypothesis posits that environmental amenities are inequitably low in poor and minority communities, and predicts these communities experience fewer urban environmental benefits. Some previous research has found that urban forest cover is inequitably distributed by race, though other studies have found no relationship or negative inequity. These conflicting results and the single-city nature of the current literature suggest a need for a research synthesis. Using a systematic literature search and meta-analytic techniques, we examined the relationship between urban forest cover and race. First, we estimated the average (unconditional) relationship between urban forest cover and race across studies (studies = 40; effect sizes = 388). We find evidence of significant race-based inequity in urban forest cover. Second, we included characteristics of the original studies and study sites in meta-regressions to illuminate drivers of variation of urban forest cover between studies. Our meta-regressions reveal that the relationship varies across racial groups and by study methodology. Models reveal significant inequity on public land and that environmental and social characteristics of cities help explain variation across studies. As tree planting and other urban forestry programs proliferate, urban forestry professionals are encouraged to consider the equity consequences of urban forestry activities, particularly on public land.
With the majority of the world’s human population now living in cities, urban forests provide an increasingly important range of ecosystem services, from improved air quality and climate change adaptation to better public health outcomes and increased tourism revenues. The importance of these ecosystem services in urban environments, and the central role that cities play in the lives of people around the world, have motivated various attempts to quantify the value of ecosystem services provided by urban forests. This paper reviews existing research in the fields of urban forestry, economics, sociology, and health on the value of urban ecosystem services, with a focus on cultural services, a category of ecosystem services that is of key importance to human well-being but that has suffered from a lack of empirical research. The review identified 38 studies that examined the value of mixed vegetation, 31 studies that examined the value of trees, and 43 studies that examined the value of green spaces. Psychological health is the most-studied ecosystem service category, with most research in this area focusing on the services of mixed vegetation. Social health, community economic development, and tourism are the least-studied, with most research in these areas focusing on mixed vegetation and trees. Multiple metrics were used to quantify the value of urban greenery within each ecosystem service category but only 11 metrics were assigned a monetary value. Gaps in the literature that present strong opportunities for future research include: the value of urban forests for improving social health, equitable access to ecosystem services, the impact of urban forests on community economic development, and economic valuation and green exposure metrics. We hope that this review stimulates future research in the areas highlighted and that municipalities consider including evaluations of a broad range of ecosystem services during land use planning and budgeting processes.
Estimates of air pollution removal by the urban forest have mostly been based on mean values of forest structure variables for an entire city. However, the urban forest is not uniformly distributed across a city because of biophysical and social factors. Consequently, air pollution removal function by urban vegetation should vary because of this spatial heterogeneity. This paper presents a different approach to evaluate how the spatial heterogeneity of the urban forest influences air pollution removal at the socioeconomic subregion scale. estimated using measured urban forest structure data from three socioeconomic subregions in Santiago, Chile. Dry deposition was estimated using hourly climate, mixing height, and pollutant concentration data. Pollution removal rates among the three socioeconomic subregions were different because of heterogeneous urban forest structure and pollution concentrations. Air pollution removal per square meter of tree cover was greatest in the low socioeconomic subregion. Pollution removal during 1997–1998 was different from 2000 to 2001 due to pollution concentration differences. Seasonal air quality improvement also differed among the subregions. Results can be used to design management alternatives at finer administrative scales such as districts and neighborhoods that maximize the pollution removal rates by the urban forest in a subregion. Policies that affect the functionality of urban forest structure must consider spatial heterogeneity and scale when making region-wide recommendations. Similarly, when model-ing the functionality of the urban forest, models must capture this spatial heterogeneity for inter-city comparisons.
In the framework of a recent EU funded research project (EUROSEISRISK Seismic hazard assessment, site effects s soil-structure interaction studies in an instrumented basin), a bridge pier model was constructed, instrumented and tested in the EUROSEISTEST experimental site (http://euroseis.civil.auth.gr), located close to Thessaloniki in Greece. The prior aim is the experimental investigation of the dynamic characteristics of the model, the study of the soil-structure-interaction effects, and in particular the wave fields emanating from the oscillating structure to the surrounding ground; to accomplish this task a well-designed set of free-vibration tests were conducted. Experimental results were compared with careful 3D numerical simulations of the soil-foundation structure system, in the frequency and time domain. Several fundamental aspects of SSI are discussed and the available analytical impedance expressions are compared with the experimental and numerical results of the present study. The study of the dynamic behavior of a simple SDOF system consisting of a model bridge pier with surface foundation in real soft soil conditions and the numerical FE modeling of the experiments, enable us to enhance our knowledge on various soil-structure interaction aspects.
This study was conducted to determine whether or not trees contribute to residential property value and the extent of that contribution in the areas observed. To accomplish this, homes were observed with a substantial amount of mature tree cover and homes were observed without tree cover. It is realized that there are other variables that contribute to residential property value and this information was obtained from tax cards on file in the town tax assessor's office. All possible variables were noted for each house observed including the sale price. Factor and multiple regression analysis was used to determine the effect of the independent variables on the dependent variable which is sales price of the house. The results showed that trees do contribute to property value in the areas observed. By using the equation formulated by the regression analysis, we can predict the value of homes. From the values derived by the regression analysis, it was found that good tree cover added $2,686 (or six percent of the total) to the property value of the homes observed.
