Lawns in Cities: From a Globalised Urban Green Space Phenomenon to Sustainable Nature-Based Solutions

How to successfully improve the biodiversity of city grasslands?

Urban grasslands (UG) are among the most common types of urban green areas. They are usually species poor, and spontaneous plant migration, which can increase biodiversity, is limited. To improve the range of ecosystem services provided by UG, various seed mixtures are applied during the establishment and restoration of UG. These mixtures vary in content, quality, and cost. High-quality seed mixtures are expensive and are usually only available in small amounts. Meanwhile, alternative methods of seed introduction (e.g., fresh hay application, seeds harvested by brush) have not been well studied in UG restoration, and inexpensive commercial mixtures could have low quality and lead to poor restoration outcomes. Here, we tested the effectiveness of different seed sources to create high-quality UG at two study sites. Based on the results, all seed addition methods increased the species richness of restored grasslands. The outcome of seed addition was satisfactory regardless of differences in residual vegetation species composition and soil properties between the sites. The species richness on plots that received a commercial mixture of flower meadow plants dedicated to pollinators decreased after overwintering. The alternative seed sources (fresh hay and seed incidentally collected during mowing) yielded grassland quality that was comparable to that on plots that received high-quality mixtures with known seed origin (a seminatural meadow mixture and a mixture with the addition of grasses).

Brownfield-related studies in the context of climate change: A comprehensive review and future prospects

The global climate change events are expected to augment the vulnerability of persistent organic pollutants within the global brownfield areas to a certain extent, consequently heightening the risk crises faced by these brownfields amidst the backdrop of global environmental changes. However, studies addressing brownfield risks from the perspective of climate change have received limited attention. Nonetheless, the detrimental consequences of brownfield risks are intrinsically linked to strategies for mitigating and adapting to sustainable urban development, emphasizing the critical importance of their far-reaching implications. This relevance extends to concerns about environmental quality, safety, health risks, and the efficacy of chosen regeneration strategies, including potential secondary pollution risks. This comprehensive review systematically surveys pertinent articles published between 1998 and 2023. A selective analysis was conducted on 133 articles chosen for their thematic relevance. The findings reveal that: (1) Under the backdrop of the climate change process, brownfield restoration is necessitated to provide scientific and precise guidance. The integration of brownfield considerations with the dynamics of climate change has progressively evolved into a unified framework, gradually shaping a research paradigm characterized by "comprehensive + multi-scale + quantitative" methodologies; (2) Research themes coalesce into five prominent clusters: "Aggregation of Brownfield Problem Analysis", "Precision Enhancement of Brownfield Identification through Information Technology", "Diversification of Brownfield Reutilization Assessment", "Process-Oriented Approaches to Brownfield Restoration Strategies", and "Expansion of Ecological Service Functions in Brownfield Contexts"; (3) Application methodologies encompass five key facets: "Temporal and Spatial Distribution Patterns of Pollutants", "Mechanisms and Correlations of Pollution Effects", "Evaluation of Pollution Risks", "Assessment of Brownfield Restoration Strategies", and "Integration of Brownfield Regeneration with Spatial Planning". Future brownfield research from the climate change perspective is poised to reflect characteristics such as "High-Precision Prediction, Comprehensive Dimensionality, Full-Cycle Evaluation, Low-Risk Exposure, and Commitment to Sustainable Development".

How Effective Is Environmental Protection for Ensuring the Vitality of Wild Orchid Species? A Case Study of a Protected Area in Italy

Orchids are among the plants most threatened by anthropic impact and environmental changes. Therefore, all known orchid species are protected in several countries by regional, national and international legislation. Several studies have cast doubts on the effectiveness of legislation to ensure the protection of wild orchids. We assessed the vitality of four orchid populations in a coastal area in Northern Italy, by monitoring the vegetative and reproductive traits of the orchid populations growing both in the protected sites comprising the Natura 2000 network, and in non-protected sites. We also monitored the level of environmental threat to orchid vitality. The early-flowering deceptive species (Ophrys sphegodes and Anacamptis morio) exhibited high vegetative vitality and experienced similar levels of environmental threat in the protected and non-protected areas. However, their reproductive success was strongly jeopardized, probably by a failed pollination that impeded the fruit set. The late-flowering, partially or totally rewarding species (Anacamptis pyramidalis and Anacamptis coriophora) were more strongly impacted by spring mowing and ungulate herbivory and alien species. Only for A. coriophora were the herbivory and alien species invasions lower at the protected vs. non-protected sites, which ensured a higher population vitality at the protected sites. We conclude that the environmental protection in our study area is ineffective for preserving orchids without targeted actions against specific environmental threats.

Exploring the role of nature-based typologies and stewardship schemes in enhancing urban green spaces: Citizen perceptions of landscape design scenarios and ecosystem services

This research investigates the UK citizens' perceptions of the ecosystem services (ES) created using a range of Nature-Based Solutions (NBS) in urban green spaces (UGS). The longevity of the ES derived from UGS is dependent on the effective on-going maintenance of urban landscapes, therefore this paper also gathers data on direct UGS participation specifically through the lens of civic stewardship to assess the impact of such schemes upon ES. NBS typologies were created and used, in the mixed methods study, to gauge perceptions of and preferences for alternative urban landscape design. The UGS survey collected data from 345 respondents on ES and the NBS typologies. Twelve semi-structured interviews provide qualitative data on NBS typology preferences, perceptions, and understanding of ES as well as motivations behind civic engagement in UGS in the UK. Stewardship programmes were found to increase community resilience by providing additional ES. The results showed a preference for integrating complex, multifunctional UGS into the fabric of urban centres to ensure accessibility and to maximise engagement. More complex NBS typologies were perceived to provide additional ES when compared with traditional monoculture mown grass and shrub amenity planting. Mixed native planting and Tiny Forest NBS typologies were perceived as providing more provisioning, cultural, regulating, and supporting ES. Considering both UK citizens' perceptions of the ES gained from alternative NBS and stewardship schemes in UGS represents a holistic approach that can improve the design and management of NBS in cities. This study is the first to explore both concepts in the UK and suggests a holistic UGS approach to address urban challenges, including those related to Climate Change.

Genetic structure of Trifolium pratense populations in a cityscape

Urban grasslands provide numerous ecosystem services, and their maintenance should be based on naturally regenerating plant populations. However, the urban environment is challenging for preserving viable populations, mostly because of their high fragmentation and small size, which can lead to genetic drift. We examined red clover (Trifolium pratense) in a medium-size city in Central Europe to test the cityscape effect on within- and among-population genetic diversity. We used eight inter-simple sequence repeat markers to examine the genetic structure of 16 populations, each represented by eight individuals. The isolation by resistance was analysed using a least cost patch approach, focusing on gene flow via pollinators. We found great variation among T. pratense populations, with no discernible geographic pattern in genetic diversity. We linked the diversity to the long history of the city and high stochasticity of land use changes that occurred with city development. In particular, we did not find that the Odra River (ca. 100 m wide) was a strong barrier to gene transfer. However, notable isolation was present due to resistance and distance, indicating that the populations are threatened by genetic drift. Therefore, gene movement between populations should be increased by appropriate management of urban green areas. We also found that small urban grassland (UG) patches with small populations can still hold rare alleles which significantly contribute to the overall genetic variation of T. pratense in the city.

Impact of native-plants policy scenarios on premature mortality in Denver: A quantitative health impact assessment

BACKGROUND

Cities often use non-native plants such as turf grass to expand green space. Native plants, however, may require less water and maintenance and have co-benefits for local biodiversity, including pollinators. Previous studies estimating mortality averted by adding green space have not considered the provision of native plants as part of the greening policies.

AIM

We aim to estimate premature deaths that would be prevented by the implementation of native-plants policy scenarios in the City of Denver, Colorado, USA.

METHODS

After conducting interviews with local expert stakeholders, we designed four native-plants policy scenarios: (1) greening 30% of all city census-block groups to the greenness level of native plants, (2) adding 200-foot native-plants buffers around riparian areas, (3) constructing large water retention ponds landscaped with native plants, and (4) greening parking lots. We defined the normalized difference vegetation index (NDVI) corresponding to native plants by measuring the NDVI at locations with known native or highly diverse vegetation. Using a quantitative health-impact assessment approach, we estimated premature mortality averted under each scenario, comparing alternative NDVI with the baseline value.

RESULTS

In the most ambitious scenario, we estimated that 88 (95% uncertainty interval (UI): 20, 128) annual premature deaths would be prevented by greening 30% of the area of census block groups with native plants. We estimated that greening 30% of parking-lot surface with native plants would prevent 14 annual deaths (95% UI: 7, 18), adding the native buffers around riparian areas would prevent 13 annual deaths (95% UI: 2, 20), and adding the proposed stormwater retention ponds would prevent no annual deaths (95% UI: 0, 1).

CONCLUSION

Using native plants to increase green spaces has the potential to prevent premature deaths in the City of Denver, but results were sensitive to the definition of native plants and the policy scenario.

The effect of grassland type and proximity to the city center on urban soil and vegetation coverage

Urban soils with associated vegetation are important components of urban ecosystems, providing multiple regulating and supporting ecosystem services. This study aimed to analyze the differences in the soil chemistry and vegetation of urban grasslands considering urbanization gradient and urban grassland type (UGT). We hypothesized that the chemical properties of soil, such as metal content, as well as vegetation traits, differ according to grassland type (lawns, grasslands in parks, grasslands on river embankments, and roadsides) and the location of grassland patches (city center versus peripheries). Our samples included 94 UGT patches which each patch represented by four square sampling plots sized 1 m². The results showed high differentiation of measured traits unrelated to UGT and location. The exception was K content, with a relatively high concentration in lawns, and some metals (Cd, Cu, Pb, Zn), with higher concentrations in the city center than in the peripheries. We found two grassland patches located in the city center where the concentrations of Pb, Zn, and Cu exceeded the level authorized by Polish standards. In the case of vegetation traits, the variability was not structured considering the UGT and location of the patches, except for bare soil cover, which was higher in lawns in the city center compared to embankments in the peripheries. We observed correlations between vegetation traits and soil chemical properties. The vascular plant species richness decreased when N, P, and C content, along with an increase in grass cover and a decrease in herbs.

Balancing the management of powerline right-of-way corridors for humans and nature

Green space in electric powerline rights of way (ROWs) can be a source of both ecosystem services and disservices in developed landscapes. Vegetation management within the ROW may influence tradeoffs that maximize potential services or disservices. Frequently mowed ROWs managed as lawn harbor less biodiversity than ROWs with taller vegetation, but may be preferred by people for aesthetic reasons and because they provide space for recreational activities. We conducted a survey of residents living by ROWs in the Chicago, Illinois USA metropolitan area to determine if residents prefer ROWs managed as lawn over those managed as native prairies or allowed to grow freely with only woody vegetation removed ("old-field ROWs"). We found that respondents did not prefer mowed over prairie or old-field ROWs. Furthermore, respondents living near mowed ROWs were least likely to think that the ROW is attractive, while those living near prairie ROWs were most likely to. Survey respondents tended to believe it was important for ROWs to provide habitat for wildlife, and wildlife observation was the most frequently reported activity conducted in the ROW. Finally, we found that a respondent's perception of biodiversity in the ROW was more closely correlated with positive feelings about the ROW than measured biodiversity levels. Our results suggest that managing ROWs for wildlife habitat is fully compatible with managing them for human enjoyment. We therefore recommend that where possible, ROW vegetation is managed in a more "natural" way than lawn because it has the potential to benefit both wildlife and people.

Phenology of grassland plants responds to urbanization

Understanding phenological responses of plants to changing temperatures is important because of multiple associated ecological consequences. Cities with their urban heat island can be used as laboratories to study phenological adaptation to climate change. However, previous phenology studies focused on trees and did not disentangle the role of micro-climate and urban structures.

We studied reproductive phenology of dry grassland species in response to micro-climate and urbanization in Berlin, Germany. Phenological stages were recorded weekly at the individual plant level for five native grassland species across 30 dry grassland sites along an urbanization and temperature gradient. We estimated 50% onset probabilities for flowering and seed maturation of populations, and analysed variation in onset dates using regression models.

Early flowering species significantly advanced flowering phenology with increasing mean air temperature but were little influenced by urbanization. By contrast, late-flowering species showed significant phenological responses to both air temperature and urbanization, possibly because micro-climate was most affected by urbanization in late summer. Surprisingly, not all grassland species showed an advanced phenology with increasing intensity of urbanization.

This contradicts observed patterns for urban trees, indicating that phenological shifts in urban areas cannot be generalized from the observation of one growth form or taxonomic group. Growth form appears as a possible determinant of phenological responses. Results suggest that the phenology of dry grassland species may directly respond to the urban heat island, albeit with variable direction and magnitude. This has implications for ecosystem services, shifted allergy seasons, changes of biogeochemical cycles and potential ecological mismatches.

Different photosynthetic adaptation of Zoysia spp. under shading: shade avoidance and shade tolerance response

Reduction of ambient solar radiation is an important external challenge for plants, which affects photosynthesis and morphogenesis in agroforestry or gardening. As bottomed sessile organisms, turfgrasses have a set of sophisticated photosynthetic strategies to survive and deal with this abiotic stress. Zoysiagrass (Zoysia spp. Willd.) is an important warm-season, perennial turfgrass that tolerates adversity, wear, trampling and extensive management. However, whole photosynthetic characteristics reaction of the zoysiagrass to shade stress have not been described because our knowledge in this area is very limited. In this study, 85% shade treatment was applied to nineteen zoysiagrass genotypes, and morphological observations and extensive determinations on plant heights, photosynthetic pigments, fluorescence dynamic curves among other parameters were made. The results showed that vegetal and photosynthetic responses of zoysiagrass were affected by shade treatment to varying degrees. Further analysis based on the principal component, subordinate function analysis and clustering methodology revealed that different shading response strategies were adopted by zoysia under shade surroundings. They were divided into four categories. The strongest shade-avoidant response strategy was adopted by 'ZG48' and 'WZG59', which had the largest comprehensive evaluation (D) values, and the stabilized shade-tolerant response was taken on by 'ZG-3' and 'ZG64', which had the lowest D values. Other varieties applied a medium strategy but with a certain tendency. These findings provide new insights into different shading response tactics of turfgrass: shade avoidance and shade tolerance response, which could be selected for further elucidation of the molecular mechanism of plant adaptation to shade environments.

Contribution of Home Gardens to Sustainable Development: Perspectives from A Supported Opinion Essay

Home gardening has a long history that started when humans became sedentary, being traditionally considered an accessible source of food and medicinal plants to treat common illnesses. With trends towards urbanization and industrialization, particularly in the post-World War II period, the importance of home gardens as important spaces for growing food and medicinal plants reduced and they began to be increasingly seen as decorative and leisure spaces. However, the growing awareness of the negative impacts of agricultural intensification and urbanization for human health, food quality, ecosystem resilience, and biodiversity conservation motivated the emergence of new approaches concerning home gardens. Societies began to question the potential of nearby green infrastructures to human wellbeing, food provisioning, and the conservation of traditional varieties, as well as providers of important services, such as ecological corridors for wild species and carbon sinks. In this context. and to foster adaptive and resilient social-ecological systems, our supported viewpoint intends to be more than an exhaustive set of perceptions, but a reflection of ideas about the important contribution of home gardens to sustainable development. We envision these humble spaces strengthening social and ecological components, by providing a set of diversified and intermingled goods and services for an increasingly urban population.

Rethinking urban park irrigation under climate change

Climate change is forcing cities to reassess their water management practices, particularly for water-intensive applications like park irrigation. If water scarcity requires governments to deviate from current park management norms and allocate less water towards parks, it is essential that park managers design spaces that maintain community wellbeing. We apply the hedonic pricing method and use detailed park management information to assess the value of parks in a region where local climatic conditions require extensive irrigation to keep turf green, and where climate change is further constraining water supplies. Here we show that the impacts of irrigation on the value of parks differ depending on the dwelling types of the nearby housing populations that they serve. In most cases, the convention that parks have to be irrigated to deliver ecosystem services to the public is supported. However, we find that non-irrigated park areas are also valued positively by nearby apartment dwellers. Accelerating rates of urbanization and shifts towards high-density living may support the development of more diverse park options that are less water-intensive. Increased visibility of these alternative park forms, which could include more areas of native vegetation that do not require irrigation, may subsequently influence public expectations for landscape design.

Seeds harvested during mowing from semi-natural grasslands as an ad hoc but effective solution for grassland restoration

Species-rich grasslands formed by local ecotypes of native species provide numerous ecosystem services both in rural areas as well as urban grasslands. Nonetheless, their area is still too small, making grasslands one of the most frequently restored habitats. Successful restoration requires high-quality seed material, which is expensive and often not easy to acquire. In this study, we tested the potential of seeds accidentally collected during the mowing of a semi-natural grassland for grassland restoration. We tested seed purity, species composition, and germination capability in both laboratory and field conditions. Ninety percent of the collected material consisted of pure seeds of numerous species. Their germination capability was relatively low but still sufficient for successful grassland restoration under a typical seed density/mass per unit area seeding ratio. The germination capacity was the highest in the first two weeks after sowing and increased with overwintering seed storage. The results suggested that the seeds could be successfully used for species-rich grassland restoration. In terms of advantages, the seed mixture had a low cost and contained native species seeds representing local ecotypes. In terms of disadvantages, there was a relatively low amount of seed material and an inability to plan the time of seed harvesting. Thus, the use of the accidentally collected seeds can be considered an effective but rather ad hoc solution.

Namares—A Surface Inventory and Intervention Assessment Model for Urban Resource Management

Densely built-up areas are challenged by reduced biodiversity, high volumes of runoff water, reduced evaporation, and heat accumulation. Such phenomena are associated with imperviousness and low, unsustainable utilisation of land and exterior building surfaces. Local authorities have multiple objectives when (re-)developing future-proof districts. Hence, exploiting local potentials to mitigate adverse anthropogenic effects and managing the resource of urban land/surfaces have become key priorities. Accordingly, a five-level hierarchy for a land-sensitive urban development strategy was derived. To support the operationalisation of the hierarchy, we present the model Namares, a highly resolved GIS-based approach to enable spatially explicit identification and techno-economic and environmental assessment of intervention measures for advantageous utilisation of available surfaces per land parcel. It uses existing data and covers the management of economic, natural, and technical resources. Nine intervention measures are implemented to identify potentials, estimate investments and annual costs, and assess the appeal of existing subsidies. The approach was applied to a case study redevelopment area in a large city in Germany. The results provide spatially explicit information on greening potentials, estimated investments, subsidy demand, and other quantified benefits. The case study results show the limited potential for additional unsealing of impervious surfaces by transforming ca. 10% of sealed ground surface area into new urban gardens. At the same time, up to 47% of roof and 30% of facade surfaces could be utilised for greening and energy harvesting. The approach enables a comprehensive localisation and quantitative assessment of intervention potentials to enhance decision support in land-sensitive urban development strategies.

A transformative mission for prioritising nature in Australian cities

Australia is experiencing mounting pressures related to processes of urbanisation, biodiversity loss and climate change felt at large in cities. At the same time, it is cities that can take the leading role in pioneering approaches and solutions to respond to those coupling emergencies. In this perspective piece we respond to the following question: What are the required transformations for prioritising, valuing, maintaining and embracing nature in cities in Australia? We adopt the mission framework as an organising framework to present proposed pathways to transform Australian cities as nature-positive places of the future. We propose three interconnected pathways as starting actions to steer urban planning, policy and governance in Australian cities: First, cities need to establish evidence-based planning for nature in cities and mainstream new planning tools that safeguard and foreground urban nature. Second, collaborative planning needs to become a standard practice in cities and inclusive governance for nature in cities needs to prioritise Aboriginal knowledge systems and practices as well as look beyond what local governments can do. Third, for progressing to nature-positive cities, it is paramount to empower communities to innovate with nature across Australian cities. Whilst we focus on Australian cities, the lessons and pathways are broadly applicably globally and can inspire science-policy debates for the post COP15 biodiversity and COP26 climate change implementation processes.

Principles for urban nature-based solutions

Nature-based solutions (NBS) were introduced as integrated, multifunctional and multi-beneficial solutions to a wide array of socio-ecological challenges. Although principles for a common understanding and implementation of NBS were already developed on a landscape scale, specific principles are needed with regard to an application in urban areas. Urban areas come with particular challenges including (i) spatial conflicts with urban system nestedness, (ii) specific urban biodiversity, fragmentation and altered environments, (iii) value plurality, multi-actor interdependencies and environmental injustices, (iv) path-dependencies with cultural and planning legacies and (v) a potential misconception of cities as being artificial landscapes disconnected from nature. Given these challenges, in this perspective paper, we build upon and integrate knowledge from the most recent academic work on NBS in urban areas and introduce five distinct, integrated principles for urban NBS design, planning and implementation. Our five principles should help to transcend governance gaps and advance the scientific discourse of urban NBS towards a more effective and sustainable urban development. To contribute to resilient urban futures, the design, planning, policy and governance of NBS should (1) consider the need for a systemic understanding, (2) contribute to benefiting people and biodiversity, (3) contribute to inclusive solutions for the long-term, (4) consider context conditions and (5) foster communication and learning.

Assessing Xeriscaping as a Retrofit Sustainable Water Consumption Approach for a Desert University Campus

Assessing water usage associated with urban green infrastructure is crucial for water resource management and sustainable planning of desert campus areas. A public university campus layout in the desert region is considered an urban city subject to urban water consumption (UWC) of significant intensity and extent, even though the urban layout is essential to all campus occupants’ comfort and environmental sustainability needs. Hence, there is a need to reduce its detrimental effects through sustainable methods for campus water content. This study focuses on assessing urban xeriscaping landscape quantities as a practical potential approach to support university campus decision-makers in reducing urban water consumption and preserving the urban campus water content as asset management and life quality. Four selected landscape field experiments were undertaken by adopting xeriscaping landscape design instead of existing conventional urban design at King Faisal University’s (KFU) campus layout, Al-Ahsaa, Eastern Province, Saudi Arabia. The study built a specific practical sustainability retrofit approach in water conservation from conventional to xeriscaping method inside the existing public desert campus area. Applying the study approach framework considering xeriscaping layout design provided sustainability requirements, retrofit approach, and pathway to effective landscape mapping, based on reasonable and accurate quantities of xeriscaping landscape items, to convert the KFU campus layout as a low water consumption campus with an average reduction of 41% water consumption within the remaining campus layout. The results of this study contribute to the water conservation and management in university desert campus and opens the door for other studies on the use of this approach for thermal reduction, economic and environmental benefits beside its value for water reduction.

The Effect of the Distance from a Path on Abiotic Conditions and Vascular Plant Species in the Undergrowth of Urban Forests and Parks

Urban forests and parks are essential for the maintenance of biodiversity as well as human health and well-being. Residents and tourists commonly use urban forests and parks for recreational and sport purposes, contributing to changes in vegetation. This study aimed to assess the effect of distance from formal paths on the abiotic conditions, vegetation cover, as well as ecological diversity of vascular plant species in the undergrowth of urban forests and parks. The investigations were carried out in 2021 in 10 urban forests and 10 urban parks located in Kraków (southern Poland), using a total of 400 plots (1 × 1 m) situated in close (CL) and further (FU) vicinity of formal paths. We found a positive effect of the distance from the path on the depth of the compact soil layer, vegetation cover and height of the tallest shoot in the undergrowth of urban forests and parks. On the other hand, the distance from the path had a negative effect on the number of vascular plant species in the undergrowth in both forests and parks. Forests and parks differed significantly from each other in light intensity, the content of P in soil, depth of compact soil layer, number of species, as well as in cover-abundance of species representing different life forms, dispersal types, habitat affiliations and origins. Trampling leads to low plant cover and height of the undergrowth, as well as contributing to shallow localization of the compact soil layer near paths. Human movement on paths (walking, running, biking) with accompanying pets contributes to the successful dispersal of plants, resulting in high species richness. High light intensity in urban parks enhances the total number of species, cover-abundance of meadow and grassland plants, as well as cover-abundance of hemicryptophytes. The number of alien species was higher in parks than in forests, but the cover-abundance of alien plants was higher in forests than in parks. Urban forests are more suitable for the growth and biomass production of some alien herbs than urban parks, as mowing commonly used in parks appears to be an important factor in reducing their cover abundance. Regular fertilization and irrigation contribute to the high content of phosphorus in the soil, as well as to the high cover-abundance of meadow and grassland plants in urban parks. Urban forests enhance cover abundance of plants with dispersal mechanisms of the Bidens and Lycopodium types, whereas urban parks promote cover abundance of plants with the dispersal of the Allium type. Further study is needed to confirm the role of urban forests and parks in the preservation of ancient forest species, as well as to develop an appropriate design of paths that will allow the protection of vegetation and soil in urban forests and parks.

People’s Perception of Nature-Based Solutions for Flood Mitigation: The Case of Veneto Region (Italy)

Floods have become more frequent due to a growing number of extreme rainfall events linked to climate change and increased urbanization. Additionally, 66% of the world’s population is expected to live in urban areas by 2050, making flood prevention and risk reduction increasingly important. Sustainability, resilience and ecosystem services are essential to increase human well-being in urban environments. Nature-based Solutions (NBS) can provide all the benefits of urban green spaces combined with flood mitigation. This work aims to provide useful information to promote the adoption of NBS to build communities resilient to climate change by exploring how people’s perception of and willingness to implement some NBS. To this end, an online survey was conducted to investigate the knowledge and the perception of NBS and grey infrastructures among people in Veneto, a north-Eastern region of Italy. Data analysis revealed a significant correlation between previous knowledge of water management systems and the perceived effectiveness of some NBS. Behaviors linked to the level of connection with the territory have also been found to influence the perceived effectiveness of NBS. This study provides insights into the dynamics behind the implementation of NBS to reduce the risk of urban flooding and can help policymakers adapt urban plans to promote the adoption of NBS.

A Preferred Road to Mental Restoration in the Chinese Classical Garden

The impact that classical gardens have on the well-being and quality of life of visitors, especially city dwellers, is an important topic. Scholars have previously focused on landscape aspects, such as water bodies, plants, rocks, chairs, pavilions, and public squares, in various green spaces but have overlooked the road settings that visitors walk on. This study used the Du Fu Thatched Cottage Museum as the subject region and employed a convenience sampling method (n = 730) to analyze the preference and mental restoration of different road settings of Chinese classical gardens. According to the findings, the majority of visitors felt that the road settings in these classical gardens provided psychological recovery, and half of the roads received a preference score of five or above. The regression results indicated that nature, culture, space, refuge, and serene were found to be important predictive dimensions for both mental restoration and preference. Furthermore, this study divides landscape elements in road settings into two major categories (natural and artificial elements) and eight subcategories (trees, shrubs, lawns, roads, fences, walls, decorations, and buildings) to investigate the relationship between various types of specific road setting elements and visitors’ perceived preferences as well as restorability. The correlation results showed that in terms of preference, tree > lawn > path > fence > shrub > wall; in terms of restoration, tree > lawn > shrub > fence > path > decoration > building > wall. Overall, the findings of this research can improve visitor preferences and restoration in a given environmental setting, resulting in a more enjoyable experience.

Sustainable Management Practices for Urban Green Spaces to Support Green Infrastructure: An Italian Case Study

Traditional land-use planning models have proven inadequate to address contemporary issues in sustainable development and protection governance. In recent years, new ‘performance based’ approaches that integrate ecosystem services (ES) provided via green infrastructure (GI) into traditional spatial planning models have been proven to reach a higher level of environmental performance, necessary to improve quality of life for all people. In Italy, there are no mandatory planning instruments to design and manage GI, which still remains a component of the traditional land-use plan. Here, the development of urban green spaces (UGS) based on ‘quantitative assessment’ is not suitable for guaranteeing the supply of ES. In addition, the scarcity of financial resources to develop ‘green standards’, as prescribed in the land-use plan to strategically design the GI, is an issue for most Italian public administrations. The paper provides the results of a test case conducted in a public green area of the city of Ancona, where the experimentation of a diversified maintenance strategy of an urban lawn significantly reduced the management cost and improved the environmental performance of green spaces. The identification of a unified management strategy to be applied to all the public UGS can help to achieve better results in support of sustainability, to redesign the continuity of GI and to develop strategies for future urban green master plans.

Buffer Green Patches around Urban Road Network as a Tool for Sustainable Soil Management

Urban areas are facing a range of environmental challenges including air, water and soil pollution as a result of industrial, domestic and traffic emissions. In addition, global climate change is likely to aggravate certain urban problems and disturb the urban ecology by increasing the frequency and severity of extreme weather events. In the context of urbanization growth and the consequent impact on the environment, there is a growing interest in maintaining urban soil quality and functions as they are the medium for green infrastructure development. Furthermore, urban soils are becoming one of the key factors in the delivery of many ecosystem services such as carbon storage, climate regulation, water flow regulation, etc. On the other hand, urban soils are well-known to be a major sink of air pollutants due to the wet and dry atmospheric deposition and recirculation. Soil has the ability to degrade some chemical contaminants but when the levels are high, urban soils could hold on large amounts and pose a risk to human health. A cost-effective technological solution is to use the ability of some plant species to metabolize, accumulate and detoxify heavy metals or other harmful organic or inorganic compounds from the soil layer. The establishment of urban lawns (grass covered surfaces) is a helpful, environmentally friendly, economically sustainable and cost-effective approach to remove contaminants from polluted soils (terrains), which also has some aesthetic benefits. In this paper, an overview of the benefits and limitations of urban lawn construction is presented. The focus is on the perspectives for sustainable management of urban lawns, especially as buffer green patches in the road network surroundings, that can represent strategies to provide ecological and social multifunctionality of urban soils, and thus, increasing their ecosystem services capacity. Specifically, the paper highlights (i) the possibilities for phytoremediation of urban soils, (ii) potential of some perennial grasses and (iii) key issues that should be considered in the planning and design of urban lawns.

Editorial for Special Issue “Nature-Based Solutions (NBS) in Cities and Their Interactions with Urban Land, Ecosystems, Built Environments and People: Debating Societal Implications”

Today’s cities increasingly serve as the nexus between nature and people in times of strong urban growth and, in some cases, urban decline [...]

Where trees cannot grow - Particulate matter accumulation by urban meadows

It has already been proven that trees and shrubs, can efficiently remove particulate matter (PM) from air. However, almost nothing is known about PM accumulation by herbaceous plants (grasses and forbs) found in urban meadows. Meadows, unlike trees and shrubs, can be located close to roads, one of the main sources of PM in cites. The aim of this study was to investigate the tolerance to urban condition and PM accumulation in the immediate roads vicinity of selected plants species in urban meadows. PM accumulation of annual and perennial meadows was compared with that of lawns. Results were interpreted in the context of species composition, biomass production, soil conditions and ambient PM concentrations. Of the species grown in annual meadows, the highest PM accumulation was found in Achillea millefolium L., Chenopodium album L. and Echium vulgare L., while Centaurea scabiosa L., Echium vulgare L. and Convolvulus arvensis L. accumulated the largest amounts of PM in perennial meadows. PM deposition on plants was positively correlated with a feathery leaf shape. For species in the annual meadows, a positive correlation was also found between PM accumulation and the wax content on plants. The presence of hairs on leaves, leaf size and plant growth pattern had no effect on PM deposition on plants. PM accumulation in one square metre of urban meadow was on average greater than that of lawn, regardless of meadow species' composition, age and location. The greatest accumulation of PM was found in a perennial meadow with low biodiversity but the greatest biomass. It would appear that the biomass produced by meadows and canopy structure has a crucial impact on the amount of PM accumulated by meadow plants. The results obtained indicate that meadows could be an important element of nature-based solutions for mitigating air pollution in urbanised areas.

Ecosystem Services and Disservices of Vegetation in Recreational Urban Blue-Green Spaces—Some Recommendations for Greenery Shaping

Urban water bodies are an important asset in terms of climate change. The accompanying vegetation is an integral part of the waterside space system and a source of ecosystem services and disservices. The composition of greenery in waterside spaces should therefore be preceded by detailed research. This research would be the basis for the development of recommendations for enhancement of the positive impact of vegetation on humans and minimisation of its negative effect. The aim of the study was to identify ecosystem services and disservices of vegetation in the four most important waterside recreation spaces in the city of Rzeszów, Poland, and to develop plant composition guidelines. A detailed inventory of vegetation and aerobiological monitoring of the presence of airborne allergenic pollen grains and fungal spores were carried out. Next, the ecosystem services and disservices of the vegetation were determined based on literature data and on our expert judgement. Additionally, a counting of the number of visitors to waterside areas was conducted. All these steps were used to develop recommendations for shaping the vegetation of study areas. The results of the investigations show that the boulevards along the artificial lake function completely differently than other investigated places as the area resembles an urban park, and the water is not the main attraction in this space. The vegetation of the boulevards and the nearby gravel-pit bathing area has mostly a spontaneous character and offers the widest range of ecosystem services and disservices. The management of the vegetation should focus on its health-enhancing values. The vegetation growing near the outdoor swimming pools has been designed by man. Nevertheless, it requires recomposing and is targeted specifically at the enhancement of the visual attractiveness. Additionally, there is a need for planting compact deciduous trees that will provide shade at the multi-media fountain.

Homeowner preferences drive lawn care practices and species diversity patterns in new lawn floras

Households intensively manage lawns to create uniformly green, low diversity plant communities. Because lawns occupy a large proportion of urban green space, they are a crucial case for understanding how people manipulate urban vegetation. In this study, I focused on 58 homeowners who purchased a newly constructed home and yard in the Seattle Metropolitan Statistical Area, USA, to see how preferences, lawn care regimes and new lawn floras develop within a multi-scalar urban environment. A typical homeowner watered 3 times in spring, watered 24 times in summer, applied fertilizer twice, mowed 21 times and edged 15 times. Most new lawn turfgrasses were Lolium perenne, Poa pratensis and/or Festuca spp. Mean species richness was 6.5 ± 5.3 species. The most frequent species were non-native and cosmopolitan (turfgrasses, Hypochaeris radicata, Taraxacum officinale and Trifolium repens). Five variables increased the probability of homeowners managing their lawns as turfgrass monocultures: living in a neighborhood with larger yards, summer watering frequency, fertilizer frequency, valuing space for children and valuing wildlife habitat. Valuing an easy to manage yard decreased the turfgrass monoculture probability. In polyculture yards, having a larger lawn was positively correlated with non-turfgrass species richness, but elevation was negatively correlated. Homeowners who valued space for children appeared to have more intensive lawn care regimes than those who valued wildlife habitat or easy to manage yards. Although lawn floras result from complex interactions of the environment and households, urban characteristics appeared to be weaker drivers of diversity than homeowner preferences and lawn care.

Human Dimensions of Urban Blue and Green Infrastructure during a Pandemic. Case Study of Moscow (Russia) and Perth (Australia)

Significant challenges of the COVID-19 pandemic highlighted that features of a modern, sustainable and resilient city should not only relate to fulfilling economic and social urban strategies, but also to functional urban design, in particular, related to urban blue and green infrastructure (BGI). Using results from a web-based questionnaire survey conducted May–July 2020 in Moscow (Russia) and Perth (Australia), this paper provides insights regarding citizens’ needs for and values of urban BGI as well as their changes during and after the COVID-19 restrictions. Survey data collected during the lockdown period have captured information about people’s ability to access green and blue spaces within urban BGI, inequalities in access, feelings, and values as well as needs and perceived pathways of future development of urban natural environment. In both cities, lockdowns limited access of people to green spaces which affected their mental and physical health. Survey results revealed that the quality, functionality, and location of open green spaces illustrated a disparity in distribution, meaning that in many cases several communities from particular neighborhoods suffered from limited access to BGI. Furthermore, in addition to analyzing perceptions and values of urban nature during the COVID-19 pandemic, some suggestions for improvement of urban BGI based on the survey responses are provided.

Connectivity assessment and prioritization of urban grasslands as a helpful tool for effective management of urban ecosystem services

Urban grasslands are usually managed as short-cut lawns and have limited biodiversity. Urban grasslands with low-intensity management are species rich and can perform numerous ecosystem services, but they are not accepted by citizens everywhere. Further, increasing and/or maintaining a relatively high level of plant species richness in an urban environment is limited by restricted plant dispersal. In this study, we examined the connectivity of urban grasslands and prioritized the grassland patches with regard to their role in connectivity in an urban landscape. We used high-resolution data from a land use system to map grassland patches in Wrocław city, Silesia, southwest Poland, Central Europe, and applied a graph theory approach to assess their connectivity and prioritization. We next constructed a model for several dispersal distance thresholds (2, 20, 44, 100, and 1000 m), reflecting plants with differing dispersal potential. Our results revealed low connectivity of urban grassland patches, especially for plants with low dispersal ability (2–20 m). The priority of patches was correlated with their area for all dispersal distance thresholds. Most of the large patches important to overall connectivity were located in urban peripheries, while in the city center, connectivity was more restricted and grassland area per capita was the lowest. The presence of a river created a corridor, allowing plants to migrate along watercourse, but it also created a barrier dividing the system. The results suggest that increasing the plant species richness in urban grasslands in the city center requires seed addition.

A Hybrid Method for Citizen Science Monitoring of Recreational Trampling in Urban Remnants: A Case Study from Perth, Western Australia

Vegetation trampling that arises from off-trail excursions by people walking for recreation can negatively impact the structure of understory plants in natural spaces that are an essential element of urban green infrastructure in a modern city. In addition to reducing the esthetic quality and environmental values of urban remnant and replanted native vegetation, such trampling reduces the habitat that supports wildlife populations within the urban fabric. This case study draws upon several disparate methods for measuring vegetation structure and trampling impacts to produce a hybrid method that community-based citizen scientists (and land managers and other researchers) could use to simply, rapidly, and reproducibly monitor how trampling associated with urban recreation trails impacts the structure of understory vegetation. Applying the novel hybrid method provided evidence that trampling had reduced the vegetation structure adjacent to a recreational walking trail in an urban woodland remnant in Perth, Western Australia. The hybrid method also detected ecological variability at the local ecosystem-scale at a second similar woodland remnant in Perth. The hybrid sampling method utilized in this case study provides an effective, efficient, and reproducible data collection method that can be applied to recreation ecology research into aspects of trampling associated with trail infrastructure.