Qualities and functions ascribed to urban cemeteries across the capital cities of Scandinavia

Cemeteries are not only burial places that provide a public service. They are also green urban spaces with cultural and natural qualities and could be integrated into the green infrastructure planning system. In this study, we explore the extent to which environmental qualities and functions are ascribed to urban cemeteries in the municipal master plans, green infrastructure plans and websites of the capital cities of Scandinavia. In addition, we conduct a focus-group interview in Oslo with six municipal employees representing green space planning/management, cultural heritage and cemetery administration/management, focusing on a broad perspective of qualities ascribed to urban cemeteries. The document study shows that, across the Scandinavian countries, cemeteries are mainly included in the concept of green infrastructure but they are not ascribed qualities similar to those ascribed to public green spaces; instead, most qualities are related to cultural history. However, Copenhagen municipality has a more inclusive approach, describing the cemeteries as green spaces and inviting people to use them for recreational purposes. The municipality even has a policy document with a strategy on how to combine the primary function of a burial site with new needs for recreational space. In the focus-group interview, cemeteries are described as static places, peaceful and quiet places, green spaces, spaces in which to experience darkness, and places for all (multiple use). There is relatively high agreement among interviewees about the recreational qualities of cemeteries, even though the cemetery administration/management emphasizes several times that its main focus is on accommodating the bereaved and their relatives. In the discussion, we focus on differences between the different Scandinavian countries in the qualities and functions ascribed to cemeteries, and examine potential explanations for why cemeteries are mostly described as green spaces, part of the green infrastructure, but treated as private green spaces in the urban planning context.     

The landscape of urban cemeteries in Beirut: Perceptions and preferences

Cemeteries constitute some of oldest and largest green and open spaces in Beirut. With the rapid densification of the city, and the extensive loss of green space, understanding the potential of these sites, as multifunctional landscapes, is critical for the health and sustainability of the city. Few studies on cemeteries have investigated the social and recreational values of these specific spaces, focusing mainly on the observation of the existing users and their current activities on site. As far as we know, none have examined how potential users may perceive them and what they may see as attractive in them. This exploratory study aims to investigate different perceptions of urban cemeteries in Beirut and identify preferred characteristics and landscape features that render them attractive green spaces. Face-to face interviews using a semi-structured questionnaire and a photo-sorting exercise were conducted with 29 participants. Quantitative and qualitative analyses revealed that not all cemeteries are perceived in the same way and that the presence of greenery, stewardship through organization, maintenance and care, as well as restorative qualities linked to privacy and the sense of being away from the city, were main criteria for positive perception and preference. Crowdedness, unequal treatment of dead and intrusion from surrounding context, both physically and ideologically were perceived as negative constructs and were linked to the least preferred images of cemeteries. While religious affiliations did not seem to impact preference or perception, the presence of political influence through signs and symbols was highly condemned within urban cemeteries.     

Trees in urban religious sites: An analysis of their diversity in Arequipa,Peru

Facing the trend of rapid urbanization, conserving the biodiversity of urban green spaces is a challenge, particularly in a developing region like Latin America. In this sense, it is known that urban sacred sites have significant cultural and conservation significance within cities. However, more needs to be studied about the vegetation they house. Given the scientific gap, the composition, richness and abundance of trees in urban religious sites of Arequipa established since the 16th century were examined, and temporal changes in the composition and distribution of trees between ancient and modern sites were identified. 749 trees of 54 species were recorded in 26 religious’ sites. A higher proportion of exotic species (74%) corresponds in greater quantity to fruit trees (52%). There were no significant differences in tree richness and abundance between ancient and modern sites. However, the ancient sites had higher richness (96.3%) and abundance (71.4%). Likewise, ancient sites present a preference for growing fruit trees in orchards and cloister gardens, unlike modern sites focused on increasing ornamental trees, with a predominance of conifers and palms. Despite the long history of the monuments, the size of the site and the green areas significantly influenced the richness and abundance; similarly, the care of the gardens greatly influenced a site that stored greater diversity and abundance. In this way, it is demonstrated that these culturally significant places house an important tree diversity, with species of nutritional and ornamental value for the self-provisioning of the religious and the beautification of the gardens. In addition, they contribute to environmental sustainability, providing different ecosystem services to cities with rapid population growth.     

Estimating the alignment of tree species composition with foraging practice in Philadelphia's urban forest: Toward a rapid assessment of provisioning services

Urban greenspaces (UGS) are increasingly recognized for their potential to provide provisioning services to residents foraging for food and other plant materials. The alignment of tree species composition with foraging practices in cities, and the provisioning services harvesters derive, in UGS remains less well studied. To address this gap, we draw on existing tree species data and forager practices in the City of Philadelphia to estimate the alignment between tree species composition and foraging in the city. Our approach uses an existing forest inventory, an international online database of useful species, online information for residents about useful species found in the city, and novel data about forager practices. By considering these datasets in tandem, we are able to identify useful tree species, species likely of interest to foragers, and species actively foraged, and estimate the relative abundance of species in each category. Our results suggest that managers may be able to analyze proxy data, through use of online quality ratings, to rapidly identify and assess forager interest in species found in their urban forests.     

The importance of functional connectivity in the conservation of a ground-dwelling mammal in an urban Australian landscape

The distribution of the northern brown bandicoot (Isoodon macrourus), a medium-sized ground-dwelling marsupial, was examined in habitat fragments within the urban landscape of the city of Brisbane, Australia. From surveys conducted in 68 fragments, bandicoots were found to be present in 33 (49%) despite widespread habitat loss and fragmentation. Logistic regression analysis revealed that of 13 measured independent variables, functional connectivity was the only factor that significantly predicted the presence of bandicoots within fragments, with connectivity positively correlated with the likelihood of occupation. Functional connectivity was equated to the likelihood of bandicoot immigration into the focal fragment from the nearest occupied fragment, based on the estimated resistance to movement offered by the intervening matrix. Within Brisbane, riparian habitat fragments typically have a relatively high level of functional connectivity, as thin strips of vegetation fringing waterways serve as corridors between larger riparian areas and facilitate the movement of bandicoots between patches. Analyses based on the Akaike Information Criterion revealed that the optimal model based on landscape context variables was convincingly better supported by the data than the optimal model produced from fragment characteristics. However, it is important to examine both internal attributes of habitat fragments and external features of the surrounding landscape when modelling the distribution of ground-dwelling fauna in urban environments, or other landscapes with a highly variable matrix. As urban centres throughout the world expand, it is crucial that the ecology of local wildlife be considered to ensure functional connection is maintained between habitat patches, especially for the conservation of species that are highly susceptible to fragmentation.     

Investigating the spatial distribution of urban parks from the perspective of equity-efficiency: Evidence from Chengdu,China

Urban parks play a crucial role in urban public green infrastructure, providing recreational places for urban residents while carrying values of aesthetics, ecology, humanities, economy, life, and society. However, achieving an equitable and efficient spatial layout of urban parks is a challenging task due to limited urban space resources, which requires further exploration. This study employed multisource big data and GIS technology to constructed an indicator system for evaluating the equity-efficiency of urban park spatial distribution. We examined the spatial distribution of 85 parks across 62 sub-districts in the main urban area of Chengdu, the largest city in western China and the first Park City of China. The results demonstrated that equity was polarized, with an indicator value ranging from 0 to 0.77 and an average value of 0.32. The sub-district of Sansheng had the highest equity, while Wenjia and Kanghe had the lowest equity. Twenty-one sub-districts had no parks, and the equity of park spatial distribution in these areas was low. The efficiency indicator ranged from 0.20 to 0.62, with an average value of 0.40. The efficiency of the main urban area was high in the southwest and low in the northeast. The sub-district of Huangtianba had the highest efficiency, while Jinguanyi had the lowest efficiency. In the two-dimensional quadrant of equity-efficiency, 24 sub-districts had high equity and high efficiency, 13 sub-districts had high equity and low efficiency, 4 sub-districts had low equity and high efficiency, and 21 sub-districts had low equity and low efficiency. At the district level, only Chenghua District’s park was spatial equitable and efficient, surpassing the average level of the main urban area. Finally, we discussed the findings in the context of planning policies for Chengdu in recent years. We proposed that strengthening the construction of small urban parks and green spaces, improving park facilities to meet the diverse social needs of people, and enhancing the quality and attractiveness of the parks are crucial for the future development of park green spaces in the main urban areas of Chengdu.     

Branching out to residential lands: Missions and strategies of five tree distribution programs in the U.S

Residential lands constitute a major component of existing and possible tree canopy in many cities in the United States. To expand the urban forest on these lands, some municipalities and nonprofit organizations have launched residential yard tree distribution programs, also known as tree giveaway programs. This paper describes the operations of five tree distribution programs affiliated with the Urban Ecology Collaborative, a regional network for urban forestry professionals. We analyzed the programs’ missions, strategies, and challenges as reported through surveys and interviews conducted with program staff. The programs were led by nonprofit organizations and municipal departments in New York City, NY; Baltimore, MD; Philadelphia, PA; Providence, RI; and Worcester, MA. These organizations focused their tree distribution efforts on private residential lands in response to ambitious tree canopy or planting campaign goals. We assessed these programs through the framework of urban forests as social-ecological systems and discuss the programs’ biophysical, social and institutional contexts. Programs face principle-agent problems related to reliance on individual tree recipients to meet goals; their institutional strategies meant to ameliorate these problems varied. Differing organizational and partner resources influenced the programs’ abilities to perform outreach and follow-up on tree performance. Programs attempted to connect with diverse neighborhoods through free trees, targeting areas with low existing canopy, and forging partnerships with local community groups. Given tree recipients’ demand for smaller flowering or fruiting trees, as well as lack of resources for tree survival monitoring on private lands, program leaders appeared to have turned to social measures of success − spreading a positive message about trees and urban greening − as opposed to biophysical performance metrics. We conclude with suggestions for outcomes monitoring, whether those outcomes are social or biophysical, because monitoring is critical to the sustainability and adaptive management of residential tree programs.     

A gradient analysis of urban landscape pattern: a case study from the Phoenix metropolitan region,Arizona, USA

Landscape Ecology - Urbanization is arguably the most dramatic form of land transformation that profoundly influences biological diversity and human life. Quantifying landscape pattern and its...     

Methods for the estimation of sampling sufficiency in urban forest inventories: The case of non-patterned compositions of trees on sidewalks

Sampling inventories are strategies to gather qualified information for managing urban forests, given the scarcity of budgetary resources for a complete inventory and lack of public engagement to reduce costs. However, procedures for testing sampling sufficiency can be unspecified in researches related to urban forest inventories and do not follow any specific pattern. Hence, to determine the sampling sufficiency, we tested different variables related to the trunk, crown, number of trees, and species, focusing on different aims of an inventory of trees on sidewalks. At a level of 10% of the total number of plots, each measuring 50.0 m × 3.0 m, we performed a stratified inventory of a city streetscape whose composition and quality represents most South American cities, with a non-patterned tree compostion. Sampling sufficiency was analyzed considering a limit of error of 10% and 15% by using 12 different variables. The stratification process was necessary for most of the variables analyzed (p > 0.01), with errors ranging from 5.87% to 15.28%. Sampling sufficiency was achieved for 10% of the total population of trees on sidewalks, at a 10% error limit for seven variables: diameter at breast height (DBH), cross-section area, crown diameter, crown area, number of species, and number of species per square meter of sidewalk and per kilometer of the street. However, this result was influenced by the variability of the variables used to estimate sampling sufficiency. As it is not possible to achieve different goals (tree registration, benefits, and diversity) with just one variable like the number of trees per kilometer of street, the sampling sufficiency estimation should be based on the use of at least the DBH, crown diameter, number of trees, and number of species. It would be a better strategy to ensure more reliable data estimations for sampling inventories of trees on sidewalks.     

Making trees visible: A GIS method and tool for modelling visibility in the valuation of urban trees

Tree visibility is a key determinant of cultural ecosystem services of urban trees. This paper develops a flexible, efficient and easy-to-use GIS method for modelling individual tree visibility to support tree valuation. The method is implemented as a GRASS GIS AddOn tool called v.viewshed.impact, making it available to a broad spectrum of users and purposes. Thanks to empirically validated underlying algorithms and parallel processing, the method is accurate and fast in analysing high-resolution datasets and large numbers of trees. We demonstrate the method in two use cases in Oslo, Norway, showing that it provides an alternative to field-based assessment of visibility indicators in tree valuation methods and facilitates the inclusion of complex visibility indicators not possible to assess in the field. We argue that the method could also be used for tree management and planning, urban ecosystem accounting and neighbour conflict resolution related to trees.     

A balancing act: Biodiversity and human wellbeing considerations in the management of urban forest in a global biodiversity hotspot

Environmental and urban forest managers in cities located in highly biodiverse regions may need to balance biodiversity conservation with the provision of ecosystem services to people. However, striking this balance is not easy and many competing factors influence the decision-making process. Set in the Perth Metropolitan Area, located in the global biodiversity hotspot of the Southwestern Australia Floristic Province, this study aimed to understand: (i) the extent to which a benefits-oriented approach is used by local governments to optimise biodiversity and human wellbeing urban forest outcomes, and (ii) what other factors influence the decision-making process shaping urban forest composition. Using a social-ecological framework, we conducted semi-structured interviews with 29 local government practitioners. We found that biodiversity conservation is actively considered in the planning and management of urban forest in natural areas and parks, but rarely in streetscapes. Maximising shade and cooling, and to a lesser extent enhancing sense of place, were the key benefits actively sought in streetscapes. Parks appeared to straddle the middle ground as areas with most flexibility to accommodate multiple biodiversity and human wellbeing benefits. Yet, benefits were only some of a multitude of social-ecological factors influencing the decision-making process shaping urban forest composition. In particular, streetscapes were affected by a large number of social and political factors (e.g., perceived risk and nuisance, ad-hoc decisions by elected members), many of them leading to suboptimal urban forest outcomes. For a benefits-oriented approach to prevail in complex and contested urban spaces it is important that the decision-making process is evidence-informed and capable of handling the challenges and conflicts that are likely to arise. Reactive decision-making results in a conservative, “safe” species palette that over time defines streetscapes by what they do not do (creating disservices) rather than what they do (delivering multiple biodiversity and wellbeing benefits), which ultimately is not a desired outcome in the context of an increasingly urbanized world.     

Survival is not enough: The effects of microclimate on the growth and health of three common urban tree species in San Francisco,California

Urban forest managers must balance social, economic, and ecological goals through tree species selection and planting location. Ornamental trees are often popular in tree planting programs for their aesthetic benefits, but studies find that they have lower survivability and growth compared to larger shade trees. To maximize ecosystem services within these aesthetic preferences, it is important to select species carefully based on their ability to grow in each particular climate. However, little locality-specific and species-specific data exist on urban trees in many regions. This study examines the growth, survival, and vigor of three common ornamental street trees in San Francisco’s three different microclimate zones after over 16 years since planting. While we found over 70% survival for all three species throughout the city, there were significant differences in health and vigor among microclimates for each species, likely due to differences in drought-tolerance. While Arbutus had the greatest proportion of healthy trees in the Fog Belt and Sun Belt zones, Prunus cerasifera had the greatest proportion in the Sun Belt, and Prunus serrulata had the greatest proportions in the Transition and the Sun Belt zones. This species-specific and climate-specific information will better equip urban foresters to target both planting and tree-care of these popular species appropriately to maximize the benefits provided by these street trees while still maintaining a diverse canopy. Finally, we argue that simple survival calculations can mask more complex differences in the health and ability of different urban tree species to provide ecosystem services.     

Overview on urban nature conservation: situation in the western-grassland biome of South Africa

Urban nature conservation issues in South Africa are overshadowed by the goal to improve human well-being, which focuses on aspects such as poverty, equity, redistribution of wealth and wealth creation. The growing need for urban employment is closely associated with the increase of squatting and informal settlements along the urban fringe, which contributes to habitat fragmentation and sprawling of cities. This increasing urbanisation is one of the main threats to biodiversity in the Grassland biome as the natural vegetation in and around cities in the North-West Province of South Africa is destroyed at an alarming rate. The lack of detailed ecological data is a major problem in the implementation of conservation-orientated policies in urban planning and management. This paper gives a brief overview of urban nature conservation in the world, the obstacles to implementation in South Africa and the importance of socio-economics and environmental legislation. We focus specifically on projects involving phytosociological studies and biotope mapping in cities in the western Grassland Biome of the North West Province. The visible presence of native vegetation is essential and integral to urban nature conservation. There is a vital need to present urban environmental data in a format that is convincing and useful to decision makers. We propose an integrated approach towards urban ecological studies culminating in effective urban nature conservation.     

Effect of the elevated ozone on greening tree species of urban: Alterations in C-N-P stoichiometry and nutrient stock allocation to leaves and fine roots

Anthropogenic ground-level ozone (O₃) pollution can alter the phosphorus (P), carbon (C), and nitrogen (N) of terrestrial plants’ ecological stoichiometry, which in turn affects forest productivity, nutrient utilization, and carbon sink capacity. However, there is still quite a lot of uncertainty regarding the impact of high O₃ levels on C-N-P stoichiometry in organs with a rapid turnover (i.e., fine roots and leaves) across varied functional types. This study investigated the effects of O₃ on the stoichiometry of C-N-P nutrient allocation of stocks to various plant organs, with a special focus on tree species frequently employed for urban greening. The impact of O₃ on C-N-P stoichiometry among different functional tree types was subsequently evaluated by reviewing the published literature. Under a pooling of all species, elevated O₃ decreased and leaf C and P concentrations increased, thereby decreasing the leaf C: P ratio. Elevated O₃ increased the N concentration in fine roots, thereby decreasing the C: N ratio, although no significant impact was observed in leaves. Elevated O₃ significantly reduced the leaf stocks of C (CS_leaf) and N (NS_leaf), however, there was no observed variation in these stocks in fine roots. The content of P, C, and N in fine roots and leaves in evergreen broadleaf species exceeded those in deciduous species. Elevated O₃ significantly reduced CS_leaf, NS_leaf, and PS_leaf in deciduous broadleaf species, whereas there was a significant reduction for the same in evergreen species. The literature analysis further demonstrated a larger O₃-induced increment in leaf P concentration in deciduous species as compared to evergreen species. Elevated O₃ significantly increased the difference in C and N stocks between fine roots and leaves in deciduous broadleaf species, whereas this difference was observed to decrease in evergreen species. The results of this study can facilitate an improved understanding of ecological stoichiometric responses of urban greening tree species under O₃ stress and the resulting nutrient use strategies.     

COVID-19 pandemic changes the recreational use of Moscow parks in space and time: Outcomes from crowd-sourcing and machine learning

The limited access to urban green spaces during the COVID-19 pandemic had a negative impact on the human-nature interaction in cities and human well-being. Number of visitors to green areas, initially declined due to imposed restrictions, was restored after they were lifted as established by several studies across the globe However, little is still known about changes in behavior and preferences of park visitors in the post-COVID time. In this study, we investigated spatial-temporal patterns of recreational activities in the three urban parks in Moscow (Russia) prior, during and after the COVID-19 lockdown (in 2019 and 2020). The selected parks represent two different types: a centrally located park with much infrastructure and open landscapes (Gorky Park) and parks located at the outskirts of the city center with a more forested landscape and little infrastructure (Timiryazevski and Sokolniki parks). Recreational activities were identified based on the analysis of social media photos using machine-learning algorithms. As expected, park closures during lockdown resulted in overall decrease in the number of taken photos. After the parks were re-opened, however, the number of photos did not grow immediately. The number of photos only restored after almost three months, and the visiting peak shifted to autumn. Differences between parks were related to the type of the park and its landscape structure. The lowest decrease in the number of photos was observed for the Timiryazevsky park – a semi-natural green area, while the centrally located Gorky Park was the most affected, likely due to the strictest control measures. In comparison to 2019, photos in 2020 were more evenly distributed across the area in all the three parks. Besides, ‘natural’ areas became the main attractors for the visitors - photos under ‘nature observation’ category became the most popular. Spatial distribution of the recreational activities in post-lockdown period was characterized by larger distances between photos, likely corresponding to the social distancing. COVID-19 pandemic highlighted the value of green areas for citizens, but also changed their recreational preferences and overall behavior in parks. The observed shift from high density of visitors around entertainments and attractions in 2019 to a more homogeneous and less dense distribution along the natural zones in 2020 reveals a new pattern in visitors behavior and preference, which shall be considered in spatial planning of the parks. Increasing availability of natural green areas and their integration in urban green infrastructures can become the most relevant policy to consider the crucial role of urban nature as a source of resilience in turbulent times.     

Inequalities in the quality and proximity of green space exposure are more pronounced than in quantity aspect: Evidence from a rapidly urbanizing Chinese city

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.     

Quercus ilex L. as bioaccumulator for heavy metals in urban areas: Effectiveness of leaf washing with distilled water and considerations on the trees distance from traffic

In recent years the use of plants as bioaccumulators or bioindicators has increased because enable the prediction of pollution for monitoring purposes, even in urban environments where traffic is a major source of heavy metals pollution. In this study we hypothesized holm oak (Quercus ilex L.) a valid trapping species for heavy metals. We also hypothesized that metals capture capacity by deposition on the crown is connected to the surrounding environmental characteristics and the distance of trees from the source of pollution. The study was conducted in the city of Florence. Holm oaks were selected in different sites near to heavy traffic roads. Concentrations of Zn, Pb, Cd, Cu, Fe, Mn, Cr, and Ba were analyzed through two methods: leaf washing with distilled water and leaf unwashing.One-year-old leaves (new leaves) were also compared with previous-year leaves (old leaves). Our results demonstrated the good capacity of this species to capture heavy metals (Pb, Fe, Mn, Cr, and Ba), particularly due to the presence of old leaves, which enhance the crown deposition surface. Washing was effective and it allowed testing the behaviour with regard to microelements: new leaves showed high Cu concentration, while old leaves had high Pb concentration. The dispersion of metals through the atmosphere was assessed through regression analysis, in two comparable gardens: leaves at farther distance from the traffic were richer in Zn, Pb, Mn, and Ba. The physical context of the surrounding environment was probably altering the distribution of heavy metals as barriers to dispersion, which can reach tens of metres from the source of pollution. Therefore, this work suggests that wind modelling and trees distribution and characteristics should be taken into consideration to evaluate the pollutants dispersion, especially for planning of recreational urban green areas.