Urban green infrastructure valuation: an economic method for the aesthetic appraisal of hedges

Effects of artificial night lighting on a web-building spider species in urban green spaces

The term ‘green infrastructure’ (GI) refers to a network of natural and semi-natural areas designed to provide ecosystem services. Urban green infrastructure focuses on green spaces within cities, including parks, gardens, forests, and water elements (blue infrastructure). It offers numerous benefits such as enhancing biodiversity, mitigating the urban heat island effect, acting as a carbon sink, improving air quality, aiding in stormwater management, and promoting physical and mental well-being. Urban green infrastructure also plays a crucial role in supporting regional habitat connectivity and biodiversity conservation. Urban forests play a crucial role in urban green spaces, acting as vital connectors between rural and urban areas. They serve as stepping stones and corridors for species movement, offering shelter, nesting sites, and foraging opportunities for a diverse range of organisms. However, ensuring successful ecological connectivity requires robust community engagement. Public awareness, education, and active participation in conservation efforts are essential for implementing and maintaining connectivity measures. Spatial urban planning encounters challenges in balancing social needs, financial expectations, and environmental sustainability. Key issues include identifying and designating ecological corridors and networks, integrating ecological principles into spatial planning frameworks, and leveraging technologies such as geographic information systems (GIS) and remote sensing for green space mapping and assessment. Restoring urban forest habitat patches is crucial for supporting species’ survival and migration. Conservation efforts should consider elements like trees outside of forests and spontaneous vegetation to enhance connectivity. Despite the benefits, managing urban green infrastructure comes with risks. These include biotic homogenisation, the introduction of non-native species, edge effects, human disturbances, lack of diversity, and pressure from increased housing density, all of which can negatively impact biodiversity. Various planning tools and strategies are available to mitigate these risks and ensure the successful implementation of ecological connectivity in urban green infrastructure. These strategies include incorporating green infrastructure into urban master plans, establishing protected areas and wildlife corridors, promoting sustainable land-use practices, and involving local communities and stakeholders in decision-making processes. By considering different scales and site characteristics, cities can achieve effective management of ecological connectivity and create sustainable and resilient environments.

Climate change in recent years is shaping society’s habits and life in large cities, then it will be necessary to plan and design nature-based urban solutions to meet different interests and needs. To enable this approach between cities, urban green spaces and climate change, sustainable and resilient urban growth models are needed, planned with the contribution of citizens as priority stakeholders. Citizens perceive and attribute value to Green Infrastructures (GIs), albeit in relation to different socio-economic and environmental variables, the assessment of which has only recently been addressed in specific research. This research analysed citizens’ perceptions of GIs in combating the effects of the climate change. In particular, it revealed the degree of awareness of climate change, the value attributed to GIs and, finally, the willingness to pay to contribute to the maintenance of GIs in the city. The survey was carried out in the city of Catania (Italy), through the administration of questionnaires to a sample of residents (n = 500). The results show that the citizens involved perceive GIs as strategic elements of the quality of urban life, although they are not always aware of their positive impact on climate change. Interest in the co-management of GIs was higher in the case of crowdfunding. An integrated two-step methodological scheme was applied (divided in two phases, univariate and multivariate statistical analysis), which proved effective in analysing the different needs perceived by citizens. This approach could become a useful tool for planning GIs, especially in the current context in which cities are facing challenges related to climate change and changing societal needs. Understanding citizens’ views will be strategic in directing public investments towards GIs that can improve the quality of life in the urban ecosystem.

Green and blue spaces: crucial for healthy, sustainable urban futures

Faced with a lack of fine grain data availability, in rapidly emerging urban centers of developing nations, the study explored a mapping methodology to create thematic map of public urban green space (UGS). Using GIS, a thematic map of Nagpur city, India was prepared. The objective was to prepare spatial data that are relevant for planners and policy makers, with detailed UGS typologies and to update the status of overall availability and distribution of hierarchical recreational green spaces in the city. The spatial and non-spatial data with added attributes gathered through fieldwork resulted in a holistic dataset, with high accuracy of thematic map (0.93 kappa coefficient). The recorded status of different typologies as well as the distribution of recreational UGS shows disparity in the distribution of UGS. The eastern part of the city grossly lacks UGS provisions, which is compensated by the western part with larger availability of natural green spaces. The mapping methodology is novel and effective for recording qualitative status, analyzing their spatial distribution and prioritizing the provisions of UGS. Future research integrating these spatial data with more qualitative research can provide a holistic view on benefits of UGS provisions and thus facilitate effective UGS governance aiming towards better green infrastructure and hence broader urban sustainability.

Faced with the prospect that the impact of the COVID-19 pandemic and climate change will be far-reaching and long-term, the international community is showing interest in urban green space (UGS) and urban green infrastructure utilization as a solution. In this study, we investigated how citizens’ perceptions and use of UGS have changed during COVID-19. We also collected their ideas on how UGS can raise its usability. As a result, more people became to realize the importance of UGS. In particular, the urban environmental purification function from UGS was recognized as giving great benefits to respondents. On the other hand, the patterns of UGS use were mixed with decreasing UGS use to maintain social distancing or increasing UGS use to maintain health or substitute other restricted facilities. More than half of respondents had their UGS visit patterns impacted by COVID-19. In particular, the increase rate of UGS use was rather high in the group that seldom used UGS before COVID-19. In addition, they increased the use of UGS to replace other limited facilities, and thus tended to demand an increase in rest facilities. Based on these results, this paper suggested securing social support and sustainability for the policy by reflecting users’ demand in landscape planning related to the increase of UGS in the city. This study can contribute to improving the resilience of UGS and the sustainability of urban space planning.

In recent decades, extensive research has demonstrated the positive impact of urban green spaces (UGS) on public health through several pathways. However, in the context of Latin America, particularly Mexico City, there remains a notable scarcity of evidence linking UGS use to health outcomes and an insufficient understanding of the pathways or factors underlying these associations. Therefore, this study employs Structural Equation Modeling (SEM) to investigate the intricate pathways between UGS use and residents’ perceived health in Mexico City, a densely populated urban center. The SEM integrates three key mediators: sentiments towards UGS, UGS quality, and time spent within these spaces. Survey data was collected through an online survey distributed via social media in May 2020 (n = 1,707). The findings indicate a minor yet significant direct link between UGS use and self-reported health (0.0427, p < 0.1). Conversely, the indirect pathways through sentiments towards UGS, UGS quality, and time spent in UGS were highly significant (0.1950, p < 0.01), underscoring their substantial role as mediators in the UGS use-health association. While a comprehensive understanding of the mechanisms linking perceived health to UGS use in Mexico City requires further research, this study proposes that fostering positive sentiments towards UGS, enhancing UGS quality, and encouraging extended visits to green areas could potentially amplify the perceived health benefits associated with UGS use among residents. These insights offer valuable inputs for policymaking, emphasizing the importance of integrating public perspectives to optimize nature-based solutions and broaden their positive impact within Mexico City.

Evapotranspiration from a temperate urban environment is the focus of the research presented in this dissertation manuscript. The research is conducted throughout New York City at a variety of monitored sites. Sites include a total of twelve existing and newly developed monitoring sites primarily in urban green spaces. New urban green space monitoring sites include engineered urban green spaces (e.g. bioretention areas and green roofs) as well as remnant local forests. Sites are intensively monitored with equipment including weighing lysimeters, soil sensors and climate stations. Monitoring at these sites yields novel previously unavailable data sets. Data sets from new and existing sites are used to quantify evapotranspiration using various methodologies, including weighing lysimeter, soil water depletion, evaporation pan, energy balance, Penman-Monteith based combination method (ASCE Standardized Reference Evapotranspiration Equation, short), crop coefficients and attenuating factors. Methods for the determination of evapotranspiration using onsite data sets from urban green spaces have been found to perform with fair or better agreement to actual evapotranspiration when certain conditions are met. Improved applicability of methods for the determination of evapotranspiration to urban green spaces has been demonstrated to be achievable through, for example, the development of crop coefficients. Data sets have also been used to evaluate the spatial variability in evapotranspiration and determinants of evapotranspiration across the heterogeneous urban environment. Findings suggest that engineered urban green spaces or green infrastructure installations in temperate urban environments generally evapotranspire at different rates amongst sites and in comparison to remnant forests due to physiological differences in vegetation and variable micrometeorological conditions, with the magnitude of these differences being dependent on runoff routing to installations. Furthermore, evapotranspiration has been compared to historic regional conditions finding that urban green spaces (specifically a green roof) may mimic historic evapotranspiration conditions at the site scale.

Urbanization and industrialization have escalated air pollution into a critical global issue, particularly in urban areas. Urban green infrastructures (GIs), such as parks and street trees, play a vital role in mitigating air pollution through dry deposition, the process by which air pollutants are removed by deposition onto plant surfaces or through plant uptake. However, existing studies on the dry-deposition capacity of urban green spaces are limited in their ability to reflect variations at the tree-species level, hindering comprehensive evaluations and effective management strategies. This study aims to quantitatively assess the dry-deposition capacity of the urban green spaces of Beijing and Shanghai for six major air pollutants in using an improved dry-deposition model and tree-species-specific data. Results showed that Shanghai’s urban green spaces had a monthly average dry-deposition rate of 5.5 × 10−6 s m−1, slightly higher than Beijing’s rate of 5.3 × 10−6 s m−1. Significant seasonal variations were observed, with summer showing the highest deposition rates due to favorable meteorological conditions. Broad-leaved species such as Zelkova serrata in Beijing and Photinia serratifolia in Shanghai exhibited superior dry-deposition capacities compared to coniferous species. Temperature significantly influenced dry-deposition rates for gaseous pollutants, while particulate-matter deposition was primarily affected by pollutant concentrations. This study provides critical insights into the air = purification functions of urban green spaces and underscores the importance of species selection and strategic green-space planning in urban air-quality management, informing the development of optimized urban-greening strategies for improved air quality and public health.

Amid rapid urbanization, cities are becoming increasingly compact, leading to intensified land resource constraints and environmental pressures. As a result, urban parks and green spaces have emerged as critical areas for providing cultural ecosystem services (CESs). However, the spatial distribution of CES supply and demand within urban green spaces remains significantly unbalanced, necessitating precise identification and quantification of CES supply–demand patterns to enhance ecosystem service efficiency. This study uses Nanjing, China, as a case study to develop an indicator framework for urban green space CES supply and demand, leveraging multi-source data. By employing spatial autocorrelation analysis (Bivariate Moran’s I) and a coupling coordination model, this research systematically assesses the spatial patterns of CESs in urban parks and green spaces. The results indicate that the overall CES supply–demand coordination in Nanjing exhibits a “high in the city center, low at the edges, and mismatched in the suburbs” pattern. Specifically, while 9.71% of the areas demonstrate well-matched CES supply and demand, 4.14% of the areas experience insufficient CES demand, and 3.66% face CES supply shortages, primarily in the urban outskirts, leading to a mismatch in green space distribution. This study further reveals the spatial heterogeneity of CES supply–demand matching across different urban districts. Based on these findings, this research proposes optimization strategies to improve CES allocation, providing a scientific basis for urban green space ecosystem service management and promoting the sustainable development of cities.

Urban green space (UGS) plays a vital role in mitigating the urban heat island effect. Existing studies on its cooling impacts in major Chinese cities are limited by low- to medium-resolution data, small geographic coverage, and the inconsistent analytical framework, which hinder systematic, comparable, and large-scale assessment of UGS cooling effects. This study addresses these gaps by developing a sub-meter UGS dataset covering densely populated Chinese cities and employs econometric methods to assess its cooling effect while accounting for spatial and environmental heterogeneity. Results reveal an overall land surface temperature (LST) reduction of 2.972 °C associated with UGS presence, and a one-standard-deviation increase in UGS corresponds to an approximate 0.123 °C LST decrease. Beyond the overall effect, we observe substantial spatial variation: UGS cooling is stronger in public and residential areas, open and high-rise environments, higher elevations, and drier climates. However, extreme heat diminishes UGS effectiveness, highlighting the need to strengthen green infrastructure in hotter regions. Notably, super-large cities show weaker cooling despite considerable UGS coverage, indicating inefficiencies in UGS configuration. These findings underscore the dependence of UGS effectiveness on local climatic and geographical conditions and highlight the significance of high-resolution UGS data in serving as a foundation for evidence-based urban climate adaptation strategies. The dataset is publicly released to support future research in this area. Overall, this study advances the understanding of UGS as a nature-based solution and provides insights into enhancing urban resilience to climate change. • A national sub-meter UGS dataset for 49 China’s major cities was developed. • UGS cooling effects were assessed using econometric methods. • UGS lowers LST by 2.972 °C on average in China’s major cities. • Cooling effects exhibit obvious spatial heterogeneity. • Tailored green planning and high-resolution UGS data are essential.

The notion of Ecosystem Services (ESs) is constantly increasing in interest given their provision of multidimensional values (environmental, social, economic, etc.). Nowadays ESs are at the center of green cities policies tackling the challenges of sustainability. More than 55% of the population is already living in urban areas, and this number is still rising. Within this context, challenges for sustainable development considering a circular economy perspective will be more concentrated in cities and in particular urban green spaces where strategies could be more effective for achieving sustainable urban development goals, such as improving public health, preserving biodiversity, reinforcing social cohesion, supporting the economy, providing opportunities for recreation, and helping in adapting to climate change. More specifically, the role of urban green spaces is testified by many green infrastructures policies proposed by different cities around the world. Rooftops, abandoned infrastructures and downgraded areas are some of the places that can be reused for creating new natural and green spaces within cities. Given these premises, the present paper aims to investigate the role of green areas in urban context in improving the overall quality of the space and in providing multidimensional benefits. The innovation of the present paper regards the integration of cost-based and value-based methods for the assessment of ESs. Starting from a real case study located in the city of Milan, the article illustrates the potential of combining the valuation of biophysical and economic values.

BackgroundUrban green infrastructure (GI) networks play a significant role in ensuring regional ecological security; however, they are highly vulnerable to the influence of urban development, and the optimization of GI networks with better connectivity and resilience under different development scenarios has become a practical problem that urgently needs to be solved. Taking Harbin, a megacity in Northeast China, as the case study, we set five simulation scenarios by adjusting the economic growth rate and extracted the GI network in multiple scenarios by integrating the minimal cumulative resistance model and the gravity model. The low-degree-first (LDF) strategy of complex network theory was introduced to optimize the GI network, and the optimization effect was verified by robustness analysis.ResultsThe results showed that in the 5% economic growth scenario, the GI network structure was more complex, and the connectivity of the network was better, while in the other scenarios, the network structure gradually degraded with economic growth. After optimization by the LDF strategy, the average degree of the GI network in multiple scenarios increased from 2.368, 2.651, 2.189, 1.972, and 1.847 to 2.783, 3.125, 2.643, 2.414, and 2.322, respectively, and the GI network structure connectivity and resilience were significantly enhanced in all scenarios.ConclusionsEconomic growth did not necessarily lead to degradation of the GI network; there was still room for economic development in the study area, but it was limited under existing GI conditions, and the LDF strategy was an effective method to optimize the GI network. The research results provide a new perspective for the study of GI network protection with urban economic growth and serve as a methodological reference for urban GI network optimization.

Trees stocks in domestic gardens and willingness to participate in tree planting initiatives in low-cost housing areas of the Eastern Cape, South Africa

Planning for green infrastructure and mapping synergies and trade-offs: A case study in the Yanshuei River Basin, Taiwan