Urban greening: A new paradox of economic or social sustainability?

Land Use Policy 92 (2020) 104487

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Land Use Policy journal homepage: www.elsevier.com/locate/landusepol

Urban greening: A new paradox of economic or social sustainability? a,c

Mengbing Du , Xiaoling Zhang a b c

a,b,

T

*

Department of Public Policy, City University of Hong Kong, Kowloon, Hong Kong Shenzhen Research Institute, City University of Hong Kong, Shenzhen, China School of Low Carbon economics, Hubei University of Economics, Wuhan, 430200, PR China

A R T I C LE I N FO

A B S T R A C T

Keywords: Urban green space Variegated sustainability economic Social equity Spatial patterns New York City

Cities globally have incorporated sustainable development into their planning, and led the way in responding to the world’s ecological crisis by “going green”. Urban green space accessibility is considered as the key to urban sustainability progress, not only environmentally, but also economically and socially. However, previous research rarely considers the latter two dimensions together. This study therefore joins the sustainability discussion from a new perspective, in particular the debate concerning the value of urban green spaces and whether and how they contribute to the variegated sustainability agenda? Based on data for 76,595 residential housing units in New York City, measuring the economic gains and equity losses from current urban green space accessibility reveals a paradox in sustainable development where the economic and social benefits of urban green space accessibility are seldom compatible, tending to involve a trade-off of some kind. In response, it is proposed that the spatial patterns of land use can represent a step towards multifaceted aspects of sustainability, with the provision of numerous small green areas that are “affordable and accessible” throughout the city being a more appropriate policy agenda than a few vast parks. Such a policy approach, it is argued, will provide a ‘win-win’ situation in terms of simultaneously contributing to both economic prosperity and the social justice of sustainability. This research also provided evidence for the institutional-driven countries such as China on how to learn from western experiences on planning land use patterns that are sustainable for individuals.

1. Introduction From national to local levels, Governments around the world have incorporated sustainable development into their planning. At its core, sustainability is concerned with achieving a simultaneous “win-win” of meeting the needs of humans now while at the same time protecting the needs of future generations (Stokes and Seto, 2018). This involves an aggregate of characteristics, including economic security and growth, environmental quality and integrity, social cohesion, and quality of life (Turcu, 2012). Urban green spaces have long been recognized to be important for the environment by improving the surrounding environment; they contribute to environmental sustainability, as they are well known for absorbing carbon, helping to moderate the climate, etc. In this light, cities worldwide are leading the way in responding to the global ecological crisis, especially in addressing such threats stemming from rapid urbanization as climate change and energy by “going green”. However, the value of urban green space has long debated. At one end of the debate spectrum, researchers argue that, as one type of public resource, green spaces can offer a variety of benefits, including

⁎

aesthetic enjoyment, recreational opportunities, and ecological services (Cho et al., 2006; Gómez et al., 2010; Maimaitiyiming et al., 2014; Wu et al., 2014). While, on the opposite of the spectrum, despite the benefits of delivered by urban green spaces, their provision in a dense urban environment is often costly (Panduro and Veie, 2013). Moreover, social inequality is an emerging concern associated with urban green spaces (You, 2016; Jennings et al., 2016; Kihal-Talantikite et al., 2013). This occurs when the distribution of resources in a given society is uneven, usually through the distribution of an allocation (Benabou, 2000), and is a social product that is differentiated by religion, race, gender, age, etc. (Tilly, 1998). In this regard, social sustainability usually entails a reduction in social inequality (Chiu, 2003). Although the value of green space has become the subject of extensive studies in the context of sustainability, their results are usually a mixture of positive, negative, and insignificant effects due to the different cases and methods involved (Panduro and Veie, 2013). Cities across the world are increasingly debating the best way to use lands efficiently and fairly, since land is becoming progressively more valuable and rare. Decades of decentralized U.S. cities, for instance, have also left many lands vacant, which can lead to such negative

Corresponding author at: Department of Public Policy, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong. E-mail address: [email protected] (X. Zhang).

https://doi.org/10.1016/j.landusepol.2020.104487 Received 4 April 2019; Received in revised form 21 December 2019; Accepted 19 January 2020 0264-8377/ © 2020 Elsevier Ltd. All rights reserved.

Land Use Policy 92 (2020) 104487

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1978; Freeman, 1981; Feng and Humphreys, 2018). This involves the assumption that commodities consist of a set of attributes or features. Thus, the price of a certain commodity comprises the sum of the price of its attributes (Morancho, 2003). In applying this model, there has been much research into the narrower topic of the effect of urban green spaces on property values, starting with Morales (1976) concluding that housing prices could be increased by 6 %–9 % with accessibility to good tree cover (François et al., 2002). Since then, influential work has been done in identifying an appropriate approach for assessing the influence of urban green spaces on property values, with related studies generally concentrating on the methodology of accessibility distribution (de la Barrera et al., 2016). Accessibility is also widely applied in studies of social inequality among different groups of people, with the suggestion that a good way is to quantify inequalities for such different societal groups, as racial, disabled people, females, etc. (Zhou and Parves Rana, 2012). This is the approach adopted in the present study, the methods used being fully described in the methodology section later.

external effects as a high crime rate and low property values that, in turn, tends to push homeowners in these areas into leaving the neighborhood. Thus, cities are interested in vacant land redevelopment and management (Mennis, 2014). Many U.S. cities are changing their “infill” lots into green spaces, while private and public owners in New York City, for example, are turning their lots into real estate development, often in the form of affordable housing, which has erupted in a hot debate (Voicu and Been, 2006). Hence, there is a need to evaluate the potential value of green spaces in surrounding areas in New York City in order to provide empirical evidence for planners and government officials in their land use decision making. However, there is little study that has done so. In order to fill this void and respond to this debate, this article provided the local government reliable data about how urban green space can contribute to variegated sustainability. Seeking to address these issues, this article (1) measures the economic gains from urban green space accessibility using a hedonic model in terms of housing structure, neighborhood characteristics, and location characteristics from a unique dataset comprising 76,595 housing units in New York City; (2) assesses the social equity loss from urban green space accessibility by targeting four groups of population, namely blacks, females, the elderly, and the poor; and (3) draws conclusions concerning how urban green space can contribute to variegated sustainability from a spatial-pattern-of-landuse perspective regarding urban greening strategy, and identifies the policy implications involved. That green spaces are a key to urban sustainability is not a new notion, but this approach combined with a large amount of individual housing unit data is novel in terms of assessing the different facets of sustainability and linking them to the spatial patterns of land use. Thus, this study helps determine how the provision of urban green spaces can be accomplished in such a way as to contribute to a more sustainable urban future. The remainder of this article is organized as follows. The next section summarizes the relevant literature. Section 3 describes the data and research methodology used. Section 4 provides the empirical results and estimates the value of urban green spaces in terms of both economic and social sustainability. Section 5 provides a discussion concerning how urban green spaces can contribute to sustainability. The last section concludes the paper with a summary of the key findings and some policy suggestions.

2.2. Inequality of urban green space accessibility: a social sustainability perspective Urban green spaces can facilitate activities, encourage communications, reduce noise, etc. Through these pathways, exposure to urban green spaces, including outdoor surrounding greenness and proximity to green spaces, could improve perceived well-being (Wu et al., 2018). However, “projects that benefit one district may have negative impacts next door” (Wachsmuth et al., 2016). Even though green urbanism has been promoting conceptual models and practices toward urban design in order to facilitate sustainability, social inequalities have been frequently highlighted in urban green space provision, which are argued to lead to a pattern of social unsustainability. Social sustainability is a developing concept and thus hard to be conceptualized. However, the basic criteria that will not change over time are the threefold aspects of social capital, cohesion, and exclusion. This suggests the basic development issues, including equitable access, should be considered as “higher-order” needs (Khan, 2016; Dempsey et al., 2011; Vallance et al., 2011). There is often an uneven distribution pattern of urban green spaces, making them disproportionately available to sociodemographic and socioeconomic groups (Kabisch and Haase, 2014) and raising important concerns over social justice (Davis et al., 2012; Gould and Lewis., 2012; Kabisch and Haase, 2014; Miller, 2016). Moreover, the challenges of development in large cities often result in patterns of spatially segregated different population groups (Brelsford et al., 2017). Given these concerns, urban green spaces are a crucial source of socio-economic disparities in green space access, which could lead to a pattern of social unsustainability. Therefore, urban green space accessibility is regarded as an indicator of social sustainability in the present study. Given this analysis of the inter-connections between urban green spaces and the economic and social determinants of sustainability, we can therefore hypothesize that urban green spaces involve a new paradox of economic and social sustainability (Fig. 1), even though urban green space conflicts are not new to studies examining uneven development in the field of environmentalism and a great deal of work has been carried out investigating the important functions of urban green spaces. Existing urban sustainability projects and studies of urban greening largely concentrate on the environmental and economic components of sustainability, while there is a lack of theoretical and empirical studies regarding social justice or measures of the social or distributional impact of sustainability (Eizenberg and Jabareen, 2017). In this regard, we joined the discussion on 1) How do we, particular urban planners address such urban green space paradox; 2) How does urban planning theory incorporated the variegated sustainability; 3) How do the top-down planning countries such as China could learn from western experiences on planning land use patterns that are

2. Theoretical lens from urban green spaces to ‘economic & social sustainability’: a new paradox 2.1. Urban green space accessibility and property values: an economic sustainability perspective Real estate development is highly related to sustainability as a concept, particularly in terms of economic sustainability (Kauškale and Geipele, 2017). Economic sustainability is one of the measures of a sustainable economy to represent sustainable development of an economy (Anand and Sen, 2000). An economy is sustainable only if the resulting stream of total welfare is non-declining over time (Stavins et al., 2003). Urban green spaces, with their significant role in improving the surrounding environment, are regarded as an important unit of environmental amenity that could dramatically contribute to the real estate market, thus contributing to total welfare and economic sustainability. As early as the late 1990s, researchers noticed the market value of urban green spaces and began to study the impact of urban green spaces on property values. Yet, as non-market entities, urban green spaces cannot be directly traded on an open market (Noor et al., 2014; Kong et al., 2006), which made their measurement difficult. Since then, influential work has been carried out to improve measurement accuracy. The hedonic model, for instance, has been used for a long time in many studies to measure the impact of different attributes on property values statistically (e.g., King and Mieszkowski, 1973; Harrison and Rubinfeld, 2

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Fig. 1. A new paradox of economic and social sustainability in urban green space.

GIS. The GIS Vector Data shapefiles are from Open Street Map. Data for the latter dimension comprise information from GIS data of the city and census tract data of such vulnerable populations as the black, female, elderly, and poor. Table 2 presents a description of the variables used and provides the summary of the dataset including maximum, minimum, and the average values for both the dependent variable and independent variables. Fig. 3 shows the demographic descriptions of the selected population groups in New York City.

affordable for individuals. 3. Data and methodology 3.1. Study area The study setting is New York City, located in New York State, on the U.S. east coast. The 302.6 square mile study area comprises Manhattan, Brooklyn, Bronx, Queens, and Staten Island. Having a population of 8,398,748 at the 2018 census, it is regarded as the country’s most densely populated major city (Maciag, 2013). It is also characterized by severe income inequalities across neighborhoods (Jargowsky, 1997), and has a long history of immigrants from different socio-economic population groups (Fig. 2).

3.3. Methodology 3.3.1. Measures of urban green space accessibility Accessibility is arguably the urban land characteristic with the strongest links to property values and equity. It involves two dimensions. One is spatial access, which emphasizes the spatial separation between supply (services) and demand (citizens) as a barrier or facilitator. The other is non-spatial access, which stresses nongeographic barriers or facilitators (Tao et al., 2014; Wu and Tseng, 2018). This study mainly focuses on the spatial dimension, to analyze accessibility between supplier (provider perspective) and demander (consumer perspective). Generally, accessibility measurements reflect the ease of reaching a certain destination including a work station and shopping malls, from a particular location within a particular time or cost threshold (Geurs and van Wee, 2004). Access can be reached by several methods: walking, bicycling, and driving, with accessibility methods being mainly based on the types of urban facilities involved. Here, we focus on local urban amenities that can be used daily by residents and can be reached conveniently by walking. Therefore, access is measured by walkable accessibility, which is a measure of how friendly an area is to walking, which is being usually measured by travelling time or distance. Travel distance to the nearest urban service to assess accessibility may relate to an individual’s walking ability. Thus, using travel distance to evaluate accessibility is not always a determining factor. However, considering access solely in terms of travel distance or travel time provides an incomplete picture of potential importance in the definition of access, and need to be embedded in the concepts of “easiness” and “freedom” (Wang and Mu, 2018). Measuring accessibility involves not only assessing the geographic variability of amenities between and within communities, but also considering constraints in the public service systems. In addition, measures of accessibility need to consider the number of local facilities from which residents can choose (Nobles et al., 2014). Therefore, this study focus on two dimensions of access: accessibility, which considers the time and distance barriers between residents’ locations and the amenities; and availability, or the number of amenities within walkable distances or time. Although walking distance can vary based on such factors as topology, walking pace, sense of safety and security, and presence of interesting activities along the walking route, it is generally understood

3.2. Data 3.2.1. Explanatory variables Generally, the price of a housing unit is dependent on the availability and level of multiple attributes, which can be summarized in three categories: structural, neighborhood, and location characteristics (Liu and Hite, 2013). Structural characteristics are the direct characteristics of property values; neighborhood characteristics relate to the quality of the surroundings; while location characteristics can be used to define the ease with which services can be reached from the housing units (Kong et al., 2006; Luo and Wang, 2003). The variables used in this study are summarized in Table 1. 3.2.2. Data source A large and comprehensive dataset from different sources is utilized in this study, containing 76,596 individual housing units and 2,068 census tracts to characterize the units of analysis. In aiming to explore whether urban green space can contribute to different facets of sustainability, and how, we focus on two dimensions of sustainability: economically and socially. The data set for the former dimension contains transaction information in terms of price, the structural characteristics are from the web of Zillow (http://www.zillow.com/1); the neighborhood characteristics are from American FactFinder/American Community Surveys (5-year Estimates)/2010–2014; the variables representing location characteristics, comprising CountGre, CountGro, CountSub, CountBus, and AreaGre, are obtained by network analysis in 1 Example for collecting data: after enter the http://www.zillow.com, input the area’s name: “NY” in the search box, and then zoom in http://www.zillow. com/homes/for_sale/NY/43_rid/globalrelevanceex_sort/40.69834,73.961163,40.484298,-74.260541_rect/11_zm/ website. On this page, click the residential housing unit, the data will appear in this page. And all the data can be collected from this website.

3

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Fig. 2. Study Area. Table 1 Explanatory variable.

Housing constructor characteristics

Neighborhood characteristics

Location characteristics

Variable

Source

Bedroom Bathroom Size Age Racial composition Population density Income Crime rate Job accessibility Environmental amenities Grocery stores Transportation Education

Du and Mulley (2006); Aroul and Hansz (2011); Dröes and Koster (2016); Hein et al. (2019) Willis and Garrod (1993); Limsombunchai (2004); Hyland et al. (2013) Haurin and Brasington (1996); Turnbull et al., (2006); Dröes and Koster (2016) Goodman and Thibodeau (1995); Selim (2009); Baba and Asami (2017) Harris (1999); Nguyen (2005) Irwin (2002); Anderson and West (2006) Baum et al. (2013) Thaler (1978); Pope and Pope (2012) Srour and Kockelman (2002) Famuyiwa (2018); Thibodeau (1990); Ten Siethoff and Kockelman (2002) Ryay (1999) Haurin and Brasington (1996); Clapp et al. (2008); Selim (2009)

traffic time and routes based on road conditions. Therefore, the “network analysis method” in GIS is used to avoid the disadvantages of the “radius method” by drawing distance between individual housing units and an amenity based on the roads involved (Fig. 4). However, unlike the other three local amenities, the value of green spaces not only

that most people’s daily walk will be approximately 10 min to or from a point of interest (Litman, 2015). Generally, access represented by a circle drawn around the facility with a radius equivalent to the users’ maximum desired distance (Nicholls, 2001). However, this method ignores the fact that people cannot travel in straight lines, as well as 4

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750,000 3 2 1428 77 0.62 44,778.03 84,615.49 6.4 39 0 0 5 30 0 0 0.3 1,158,735 3.08 2.14 2022.48 66.02 0.56 52501.27 101712.7 8.60 37.60 0.01 0.04 9.45 31.66 4.17 1.69 0.37 Miles

3.3.2. Measures of economic and social dimensions of sustainability in urban green space accessibility Once measured, we devise a way to characterize how urban green space accessibility affects the two key themes of economic and equity. In aiming to evaluate the impact of green spaces on property values, urban green spaces in this study include parks, gardens, and golf courses. To do this, three variables of green spaces are controlled: the area of a certain green space (AreaGre); the ratio of the area of green spaces within census tract to the area of the tract (PerGre); and the number of green spaces within walking distance to a certain residential housing unit (CountGre), of which, CountGre is the key variable, while the other two are control variables. The general hedonic model is:

P = f (x1, x2 , …, xn )

Lg (Price) =β0 + β1*C + β2*N + β3*L + ε

(2)

where Lg (Price) is the log of the housing price, C, N, and L denote the constructor, neighborhood, and location characteristics of the housing, and βi and ε are the hedonic regression coefficients and residuals respectively. Here, we apply a walkable accessibility score to quantify the social equity of urban green spaces, as this is now widely used to estimate neighborhood walkability towards an amenity based on its location. We define the walkable accessibility score of each census tract, WGsS, as: WGsS=(∑ N(Gs)* β)/N(H)

(3)

where N(Gs) is the number of urban green space within walkable areas toward each individual housing unit, β represents the coefficient, and N (H) is the number of housing units within a certain census tract. 4. Results 4.1. Economic sustainability in urban green space accessibility The spatial distribution of housing unit prices show a distinctive agglomeration pattern, with housing units around urban green spaces generally having high property values (Fig. 5). This suggest that urban green space, as a key landscape element, has a significant influence on property values in both negative and positive terms (Table 3). In contrast to the expectation that areas with more green spaces engender higher housing prices, these results indicate a negative relationship between the percentage of green spaces and property values. This apparently aberrant result might be partially attributable to vacant urban spaces with a high occupation of poor people and a high crime rate. However, the number of green spaces has a huge positive impact on property values with a coefficient of 0.212, which means an increase of 1 unit in the log of the number of green spaces within walkable distance increases the log of housing price by an average of 21.20 %. This implies that such green spaces have a significant average impact on property values with a 95 % confidence interval of 15.60%–26.79%. This finding supports the notion that a view of high-quality green spaces strongly affects property values in New York City, much higher than the 5–6 % found in previous studies of U.S. cities (Tajima, 2003),

Location characteristics

Neighborhood characteristics

Housing constructor characteristics

(1)

where P is the market price of an individual residential housing unit and x1, x2 , …, xn are the set of characteristics it embodies. Since the correlation between housing price and the estimated parameters is likely to be nonlinear, a log model is used to reflect their intercorrelations more accurately. The basic specific hedonic model used here is:

Dependent variable Independent variable

Table 2 Variable descriptions.

reflects the recreational benefits they provide, but also the pleasantness of the scenic view they bring to nearby residents. Thus, straight-line measurement is used to measure the walkable buffer around urban green spaces.

Price Number-bd Number_ba Size Age PerWhi AverPD AveHI CR ACW AreaGre PerGre CountGre CountGro CountSub CountBus DisSch

Square feet Year Percent Percent Dollars Percent Minute Square Miles Percent

Thousand dollars

Housing Price of all the residential housing units The number of bedroom of a residential housing unit The number of bathrooms of a residential housing unit The size of a residential housing unit The age of the residential housing unit The percent of white population within a certain census tract The Population density within a certain census tract Average of household income of a certain residential housing unit Crime rate in a certain census tract Average commute time to work Areas of a certain green space The ratio of the area of green spaces within census tract to the area of a certain census tract The number of green spaces within walking distance to a certain residential housing unit. The number of grocery stores within walking distance to a certain residential housing unit. The number of subway station entrances within walking distance to a certain residential housing unit. The number of bus stops within walking distance to a certain residential housing unit. The distance from a residential housing unit to the nearest school.

P50 Unit Variable

Definition

Mean

M. Du and X. Zhang

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Fig. 3. Demographic descriptions of selected population groups.

process regarding “urban greening”, in how to drive property values while simultaneously alleviating social injustice. According to the results, the number of urban green spaces and percentage of urban green spaces to a certain census tract are useful variables for describing property values. The significant positive impact of the number of urban green space patches indicates that they can raise the average property price considerably; while the negative sign of the percentage of urban green spaces within a certain census tract significantly depresses the average price. Thus, as far as environmental variables are concerned, the accessibility to green spaces is more important than their size. While a greater richness of urban green space types tends to create more leisure opportunities, it can also have a negative effect on residents living nearby in terms of noise and even a high crime rate, leading to an unsafe environment. Research into urban space dating back to the work of Jacobs (1961) and Newman (1972) on citizens’ perceptions of safety living in cities, has long advocated that high-quality urban green spaces with a strong residential population helps provide a sense of safety and security associated with environmental facilities (Rosemary et al., 2005). Thus, compared to a vast park with fewer local residents, providing several small green areas is a more appropriate approach. In addition, using the spatial explicit approach supported by GIS technology combined with the hedonic pricing model could also help to target specific locations for the creation and restoration of urban green spaces during the urban greening process by knowing the unequal and inaccessible areas to them (Kong et al., 2007a; MZainora et al., 2016). Even though such spaces are distributed throughout New York City, there is a distinctive difference between the city’s west and the east sides, with Manhattan and west Brooklyn having high accessibility, while Queens, Bronx, and Staten Island have significantly less. A range of factors, including the segregation of socioeconomic groups and spatial agglomeration, contribute to the regional unbalanced development, indicating a need for new urban green spaces in the city’s east side. Despite the important role urban green spaces play in recreational enjoyment (Kong et al., 2006) and property values, just being green is not enough since urban green spaces can lead to different spillover effects.

suggesting that natural resources are much more valued by citizens in New York City. 4.2. Social sustainability in urban green space accessibility Given the above links between urban green spaces and property values, an important emerging question is whether access to urban green space – and the economic benefits involved - is distributed in ways that disproportionately cross areas and advantage or disadvantage people on the basis of socio-economic conditions. In short, do urban green spaces contribute to equity loss? Using the spatial explicit approach supported by GIS technology combined with the hedonic pricing model could help to target specific locations for the creation and restoration of urban green spaces during the urban greening process by knowing the unequal and inaccessible areas to such spaces (Kong et al., 2007a,b; MZainora et al., 2016). Even though these spaces are distributed throughout New York City, there are distinct patterns of inequality and inaccessibility, and obvious differences between the city’s west and the east sides (Fig. 6). Manhattan and west Brooklyn have high accessibility to urban green spaces with scores much higher than the average (Table 4); while, in contrast, there are few public green spaces in Queens, Bronx, and Staten Island. These findings highlight the spatial inequality pattern of urban green space between socioeconomic population groups. Although urban green spaces are distributed citywide, there is still a spatial inequality between their accessibility by different groups (Table. 5). According to the statistical analysis, 70.51 percent of the black population have poor accessibility to urban green spaces, along with 67.22, 69.72, and 65.00 percent of the female, elderly, and poor populations respectively, due to a combination of low access and the greater travel distances involved. 5. Discussion 5.1. The paradox of urban green spaces in the prosperity of property values and the struggle for social sustainability The multivariate scope of the hedonic pricing model combined with GIS spatial analysis techniques can provide rational and accurate information concerning the apportionment of property values to multiple factors (Xu et al., 2016), and enable the role played by urban green space in New York City to be isolated and quantified. The empirical results provide composite evidence for the political decision-making

5.2. Sustainability: planning for whom? One basic question to be considered in the urban planning and policy-making process is for whom sustainability is intended. This is a basic ethical issue that has gained much attention from different fields, 6

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Fig. 4. 10 min walkable buffer toward amenities.

support for gardens in New York City is often opposed to other social goals such as affordable housing or other public uses (Voicu and Been, 2008). Moreover, small community green spaces are often perceived as a neighborhood liability (Troy and Grove, 2008) due to their characteristics of “affordability” and “accessibility”. This finding highlights the important fact that there are various ways of greening, and a dividing line is drawn according to who the green spaces serve and to what end (Connolly, 2019). In academic and policy discourse, sustainability is always a priority. Urban planners, designers, policy-makers, and etc. have rightfully identified the underlying importance of embedding sustainability into development strategies. However, they often focus on city-level components of sustainability, little has recognized from individual level. Such component of sustainability calls question the intension of urban planning. We filled this void by incorporating individual sustainability into sustainable development framework.

but is difficult to define given we cannot always discuss the concept of sustainability with those most affected (Scholtes, 2010) – there is a common presumption that every citizen should be treated equally. However, our findings suggest that, in addition to the unequal physical access to urban green spaces, inequality also exists in terms of their quality, such as in parks and community gardens, between different regions and socioeconomic groups, while peri-urban areas and vulnerable groups may only have access to unsafe and undesirable community green spaces. In this case, the city’s “going green” program needs to be focused on areas around low-income residents rather than such highlevel urban green spaces as High Line Park and Central Park which, although they offer huge benefits, are prioritized more wealthy people. Sustainable cities need to not only build up a physical framework for urban facilities, but also promote economic and social aspects, and be irreversibility involved in providing their equitable accessibility by citizens. The findings suggested that, in contrast to vast gentrification parks, small community gardens are more welcomed and valued by neighborhood residents. When vacant lots need to be reclaimed, the 7

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Fig. 5. Spatial distribution of urban green space and the price of the housing unit (The darker the color, the higher the price).

common to conclude that spatial patterns of land use serve as a step toward sustainable development. In this study, we provide a solution to enable urban green spaces to deliver both economic and social benefits. As shown in Fig. 7, while vast and gentrified amenities such as Central Park may facilitate real estate by competing for urban green space resources, they can also lead to social inequity by pricing out low-income populations. Yet, such land supply is not unique in western countries, and this pattern is shaping urban areas in the institutional-driven countries such as China and other parts of Asia. On the other hand, small and unified community green spaces can more often lead to equity gains, since they are small and can be easily reached. However, the spatial pattern of this type of green spaces is small thus generally fragmented, thus lacking diversity. These two types of land patterns now harness the language of sustainability. In contrast, mixed and diverse small green spaces serve for both economic and social sustainability, facilitating economic gains while simultaneously improving social equality. Such approach of diverse land use patterns is promising not only in western countries, but also across the top-down planning countries to incorporate variegated sustainability into urban planning from a micro perspective.

Table 3 Economic gains from urban green space accessibility. Independent Variable

Number_bd_log Number_ba_log Size_log Age_sq PerWhi_log AverPD_log AverHI_log ACW_log CR_log PerGre_log CountGre_log CountGro_log CountSub_log CountBus_log DisSch_log _cons

R-squared = 0.4777 Coefficient

Robust (Standard error)

t value

P value

.0806855** .6738012*** .2279117*** −8.33e–06*** .2419445*** −.0874905*** .2715813*** −.2602314*** .0910699*** −.0153451*** .211975*** .1040767*** −.1132442*** .1104903*** −.0809955*** 2.772694***

.0347313 .0387991 .0395605 1.43e-06 .0287543 .0178846 .0304787 .0726467 .0169049 .0036632 .0285265 .0191031 .0212726 .0154599 .0155285 .5534194

2.32 17.37 5.76 −5.81 8.41 −4.89 8.91 −3.58 5.39 −4.19 7.43 5.45 −5.32 7.15 −5.22 5.01

0.020 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000

** Indicates statistical significance at the 10 % level. *** Indicates statistical significance at the 5 % level.

6. Conclusion

5.3. Urban green space: how to contribute to variegated sustainability?

The focus of this article is not the study of urban green spaces per se, but the study of ow does urban green space contribute to different facets of sustainability. Its broad contribution lies in 1) discuss how urban green spaces have paradox results in economic and social sustainability; 2) suggest how urban planning theory incorporate the variegated sustainability; and 3) provide western experiences for institutional-driven countries such as China on how to plan land use patterns that are

Accessibility is a commodity and an input to the value of the land market, so it is difficult to promote both aspects of sustainability at the same time (Stokes and Seto, 2018). However, the spatial patterns of urban green spaces are determinants of the level of accessibility in that high accessibility can be both an economic and equity boon. Thus, it is 8

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Fig. 6. Spatial distribution of urban green space accessibility score at the census tract level.

space to facilitate real estate can ultimately lead to gentrification and the displacement of various residents, thus alleviating social inequity by benefiting citizens unequally and pricing out vulnerable residents. In response to the concerns over the economic gain-social equity loss paradox of urban green space, it is suggested here that policy should be shifted from “vast and gentrification parks” to one of “mixsized urban green spaces” that are affordable and reachable. Projects that benefit one district may have a negative impact on the next. The prospects of a win-win should be enhanced by providing numerous small “affordable” and “accessible” urban green spaces throughout the city, instead of a few vast “gentrificated” parks, to lead to economicenvironmental-social sustainable development. In addition, policy is needed to improve the connection between urban green spaces and different facets of sustainability, and measures of equity included in sustainability plans. Moreover, the results of our research provide valuable insights into the values of surrounding local residents. Such information needs can be included in the planning process to assess different policy scenarios in “urban greening” projects and applied to landuse zoning, especially in arranging local amenities and natural resources. Urban green spaces do have a significant effect on property values, and such an approach will not only can help in the better use of limited land resources in the city, but also can improve spatial equity and reduce social conflicts. The disconnection between sustainability and social justice is also reflected in the city’s current policy, and new policy is needed to improve the connection between urban green and social justice, and measures of equity included in sustainability plans. Moreover, the results of the hedonic pricing model provide valuable insights into the values of surrounding local residents. Such information needs be included in the planning process to assess different policy scenarios in “urban greening” projects and applied to land use zoning,

Table 4 Green Spaces’ Accessibility Score (Weighted Score). Census Tract Number

2068

Mean Score of Walkable Accessibility to Green Space Min Score of Walkable Accessibility to Green Space Max Score of Walkable Accessibility to Green Space Census Tracts with Scores above Mean Score

1.93 0 23.77 570 28 % 1498 72 %

Census Tracts with Scores below Mean Score

Number Percent Number Percent

Table 5 Urban green space accessibility among selected population groups.

With access Without access

Black population

Female population

Elderly population

Poverty population

476,813 29.49 % 1,139,903 70.51 %

1,130,486 32.78 % 2,317,870 67.22 %

250,691 30.28 % 577,169 69.72 %

465,750 35.00 % 864,968 65.00 %

sustainable for individuals. The results show that green spaces have a significant impact on property values, with a negative impact of the ratio of the area and a positive impact of the number of green spaces. Thus, as far as environmental variables are concerned, accessibility to green spaces is more important than their size. In addition to highlighting the urban effect of green spaces on property values, the results indicate that urban green space strategies may be paradoxical, in that the creation of green 9

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Fig. 7. Reframing variegated sustainability urban planning theory: a conceptual framework.

References

especially in arranging local amenities and nature resources. Given the study focuses on New York City, special attention is needed in generalizing the findings and their implications to other settings, especially outside the U.S. Thus, future theoretical and empirical research is needed to shed light on related studies in other cities and countries. Although cultural and economic differences make it difficult to compare western and eastern countries, longitudinal research could contribute to the full picture of “urban greening” projects from a global perspective. It should also be noted that, despite our attempt to capture a full picture of the effects of urban green spaces on New York City’s property values with detailed information, we are only able to depict the most important aspects due to our main purpose being to assess how urban green space can contribute to sustainability and its different aspects. Nevertheless, the empirical study described in this paper does provide effective information for the local government as well as the real estate industry concerning whether, or where, to invest in urban green spaces with regard to residential property values in terms of not only urban green spaces but also other contributory factors to economic and social sustainability.

Anand, S., Sen, A., 2000. Human development and economic sustainability. World Dev. 28 (12), 2029–2049. Benabou, R., 2000. Unequal societies: income distribution and the social contract. Am. Econ. Rev. 90 (1), 96–129. Brelsford, C., Lobo, J., Hand, J., Bettencourt, L.M., 2017. Heterogeneity and scale of sustainable development in cities. Proc. Natl. Acad. Sci. U. S. A. 114 (34), 8963–8968. Chiu, R.L., 2003. 12 social sustainability, sustainable development and housing development. Housing and Social Change: East-West Perspectives Vol. 221 Routledge. Cho, S.H., Bowker, J.M., Park, W.M., 2006. Measuring the contribution of water and green space amenities to housing values: an application and comparison of spatially weighted hedonic models. J. Agric. Resource Econ. 485–507. Connolly, J.J., 2019. From Jacobs to the just city: a foundation for challenging the green planning orthodoxy. Cities 91, 64–70. Davis, A.Y., J. Belaire, A., Farfan, M.A., Milz, D., Sweeney, E.R., Loss, S.R., Minor, E.S., 2012. Green infrastructure and bird diversity across an urban socioeconomic gradient. Ecosphere 3 (11), 1–18. de la Barrera, F., Reyes-Paecke, S., Banzhaf, E., 2016. Indicators for green spaces in contrasting urban settings. Ecol. Indic. 62, 212–219. Dempsey, N., Bramley, G., Power, S., Brown, C., 2011. The social dimension of sustainable development: defining urban social sustainability. Sustain. Dev. 19 (5), 289–300. Eizenberg, E., Jabareen, Y., 2017. Social sustainability: a new conceptual framework. Sustainability 9 (1), 68. Feng, X., Humphreys, B., 2018. Assessing the economic impact of sports facilities on residential property values: a spatial hedonic approach. J. Sports Econom. 19 (2), 188–210. Freeman, A.M., 1981. Hedonic prices, property values and measuring environmental benefits: a survey of the issues. Measurement in Public Choice. Palgrave Macmillan, London, pp. 13–32. Geurs, K.T., van Wee, B., 2004. Accessibility evaluation of land-use and transport strategies: review and research directions. J. Transp. Geogr. 12 (2), 127–140. Gómez, F., Jabaloyes, J., Montero, L., De Vicente, V., Valcuende, M., 2010. Green areas, the most significant indicator of the sustainability of cities: research on their utility for urban planning. J. Urban Plan. Dev. 137 (3), 311–328. Harrison Jr, D., Rubinfeld, D.L., 1978. Hedonic housing prices and the demand for clean air. J. Environ. Econ. Manage. 5 (1), 81–102. Jargowsky, P.A., 1997. Poverty and Place: Ghettos, Barrios, and the American City. Russell Sage Foundation. Jennings, V., Larson, L., Yun, J., 2016. Advancing sustainability through urban green space: cultural ecosystem services, equity, and social determinants of health. Int. J. Environ. Res. Public Health 13 (2), 196. Kauškale, L., Geipele, I., 2017. Integrated approach of real estate market analysis in sustainable development context for decision making. Procedia Eng. 172, 505–512. Khan, R., 2016. How frugal innovation promotes social sustainability. Sustainability 8 (10), 1034. Kihal-Talantikite, W., Padilla, C.M., Lalloué, B., Gelormini, M., Zmirou-Navier, D., Deguen, S., 2013. Green space, social inequalities and neonatal mortality in France. BMC Pregnancy Childbirth 13 (1), 191.

CRediT authorship contribution statement Mengbing Du: Writing - original draft, Data curation, Methodology, Software. Xiaoling Zhang: Supervision, Writing - original draft, Writing - review & editing. Declaration of Competing Interest None. Acknowledgements This work was supported by grants from the National Natural Science Foundation of China [grant numbers 71834005, 71673232]; the Research Grant Council of Hong Kong, China [grant number CityU 11271716] and Hong Kong CityU Internal Funds [grant numbers 9680195, 9610386]. 10

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Stokes, E.C., Seto, K.C., 2018. Tradeoffs in environmental and equity gains from job accessibility. Proc. Natl. Acad. Sci. U. S. A. 115 (42), E9773–E9781. Tajima, K., 2003. New estimates of the demand for urban green space: implications for valuing the environmental benefits of Boston’s big dig project. J. Urban Aff. 25 (5), 641–655. Tao, Z., Cheng, Y., Dai, Y., Rosenberg, M.W., 2014. Spatial optimization of residential care facility locations in Beijing, China: maximum equity in accessibility. Int. J. Health Geogr. 13 (1), 33. Tilly, C., 1998. Durable Inequality. Univ of California Press. Troy, A., Grove, J.M., 2008. Property values, parks, and crime: a hedonic analysis in Baltimore, MD. Landsc. Urban Plann. 87 (3), 233–245. Turcu, C., 2012. Local experiences of urban sustainability: researching Housing Market Renewal interventions in three english neighbourhoods. Prog. Plann. 78 (3), 101–150. Vallance, S., Perkins, H.C., Dixon, J.E., 2011. What is social sustainability? A clarification of concepts. Geoforum 42 (3), 342–348. Voicu, I., Been, V., 2008. The effect of community gardens on neighboring property values. Real Estate Econ. 36 (2), 241–283. Wachsmuth, D., Cohen, D.A., Angelo, H., 2016. Expand the frontiers of urban sustainability. Nat. News 536 (7617), 391. Wang, M., Mu, L., 2018. Spatial disparities of Uber accessibility: an exploratory analysis in Atlanta, USA. Comp. Environ. Urban Syst. 67, 169–175. Wu, H.-C., Tseng, M.-H., 2018. Evaluating disparities in elderly community care resources: using a geographic accessibility and inequality index. Int. J. Environ. Res. Public Health 15 (7), 1353. Wu, J., Wang, M., Li, W., Peng, J., Huang, L., 2014. Impact of urban green space on residential housing prices: case study in Shenzhen. J. Urban Plan. Dev. 141 (4), 05014023. Wu, J., He, Q., Chen, Y., Lin, J., Wang, S., 2018. Dismantling the fence for social justice? Evidence based on the inequity of urban green space accessibility in the central urban area of Beijing. Environ. Plan. B Urban Anal. City Sci., 2399808318793139. Xu, L., You, H., Li, D., Yu, K., 2016. Urban green spaces, their spatial pattern, and ecosystem service value: the case of Beijing. Habitat Int. 56, 84–95. You, H., 2016. Characterizing the inequalities in urban public green space provision in Shenzhen, China. Habitat Int. 56, 176–180. Zhou, X., Parves Rana, M., 2012. Social benefits of urban green space: a conceptual framework of valuation and accessibility measurements. Manag. Environ. Qual. Int. J. 23 (2), 173–189.

King, A.T., Mieszkowski, P., 1973. Racial discrimination, segregation, and the price of housing. J. Polit. Econ. 81 (3), 590–606. Kong, F., Yin, H., Nakagoshi, N., 2007a. Using GIS and landscape metrics in the hedonic price modeling of the amenity value of urban green space: a case study in Jinan City, China. Landsc. Urban Plann. 79 (3-4), 240–252. Kong, F., Yin, H., Nakagoshi, N., 2007b. Using GIS and landscape metrics in the hedonic price modeling of the amenity value of urban green space: a case study in Jinan City, China. Landsc. Urban Plann. 79 (3-4), 240–252. Litman, T., 2015. Autonomous Vehicle Implementation Predictions: Implications for Transport Planning. No. 15-3326. Liu, S., Hite, D., 2013. Measuring the Effect of Green Space on Property Value: an Application of the Hedonic Spatial Quantile Regression. No. 1373-2016-109264. Luo, W., Wang, F., 2003. Measures of spatial accessibility to health care in a GIS environment: synthesis and a case study in the Chicago region. Environ. Plann. B Plann. Des. 30 (6), 865–884. Maciag, M., 2013. Mapping the nation’s most densely populated cities. Governing the States and Localities. pp. 2. Maimaitiyiming, M., Ghulam, A., Tiyip, T., Pla, F., Latorre-Carmona, P., Halik, Ü., Sawut, M., Caetano, M., 2014. Effects of green space spatial pattern on land surface temperature: implications for sustainable urban planning and climate change adaptation. ISPRS J. Photogramm. Remote. Sens. 89, 59–66. Miller, J.T., 2016. Is urban greening for everyone? Social inclusion and exclusion along the Gowanus Canal. Urban For. Urban Green. 19, 285–294. Morancho, A.B., 2003. A hedonic valuation of urban green areas. Landsc. Urban Plan. 66 (1), 35–41. MZainora, A., Norzailawati, M.N., Tuminah, P., 2016. A Spatial Analysis on Gis-hedonic Pricing Model on the Influence of Public Open Space and House Price in Klang Valley, Malaysia. International Archives of the Photogrammetry, Remote Sensing & Spatial Information Sciences, pp. 41. Nicholls, S., 2001. Measuring the accessibility and equity of public parks: a case study using GIS. Manag. Leis. 6 (4), 201–219. Nobles, M., Serban, N., Swann, J., 2014. Spatial accessibility of pediatric primary healthcare: measurement and inference. Ann. Appl. Stat. 8 (4), 1922–1946. Panduro, T.E., Veie, K.L., 2013. Classification and valuation of urban green spaces—a hedonic house price valuation. Landsc. Urban Plan. 120, 119–128. Scholtes, F., 2010. Whose sustainability? Environmental domination and Sen’s capability approach. Oxford Dev. Stud. 38 (3), 289–307. Stavins, R.N., Wagner, A.F., Wagner, G., 2003. Interpreting sustainability in economic terms: dynamic efficiency plus intergenerational equity. Econ. Lett. 79 (3), 339–343.

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