查看更多>>摘要:? 2021In this study, the horizontal abatement effects of green belts on atmospheric particulate matter at different horizontal distances and plant community structures were investigated in urban roadside green belts in semi-arid areas.We collected mass concentrations of six types of atmospheric particulate matter (PM) per unit time of PM0.3, PM0.5, PM1.0, PM2.5, PM5.0, and PM10 and various meteorological indices, to compare the horizontal reduction efficiency of different distances and plant community structures on different particle sizes, and to establish a support vector machine model. The results showed that 1) the horizontal abatement efficiency of green belts was different for six particle sizes, while the horizontal abatement rate strengthened as the particle size increased. The abatement rate was significantly correlated with microclimatic factors such as temperature and humidity, but less correlated with wind speed. 2) The horizontal abatement rate of roadside green belts on atmospheric particulate matter varies with the increase of horizontal distance in a “single-peak” or “double-peak” pattern, with the best abatement effect of green belts on each particle size at a horizontal distance of 45m. Among the four types of plant community structures, the strongest abatement ability was in the arbor-shrub-herb structure. 3) The correctly tuned prediction model, based on Support Vector Machines, resulted in better horizontal abatement ability of green belts on atmospheric PM. The prediction results showed that the average horizontal abatement rate has the best abatement effect at 45–55 m, peaked at 50 m, and formed stagnant dust at 65 m. In the design of urban road green spaces in semi-arid areas, to achieve the best dust retention effect, the green belt width should be ≥40 m and it is desirable to choose arbor-shrub-herb structures. This study provides a design basis and theoretical support for urban road green space planning in semi-arid areas.
查看更多>>摘要:? 2021 The Author(s)To curb the spread of Covid-19, Singapore, like other cities, had to impose movement restriction and social distancing measures that may affect the well-being of its residents. In this paper, we assessed the potential benefits of gardening on the mental well-being of Singapore residents, based on the concept of mental resilience. We hypothesized that gardening activities promote mental resilience. A survey was administered on 8,786 participants of a “Gardening with Edibles” programme, measuring their mental resilience status, engagement in gardening activities and socio-demographic information. The mental resilience scores of participants who engaged in weekly gardening were compared with the scores derived from another survey conducted during the pandemic on an online community comprising demographically representative respondents with an interest on Covid-19 related community care. The results showed that the mental resilience of those who gardened was statistically significantly higher than the online community. Within the gardening group, those with less than one hour of weekly gardening time had significantly lower scores in their total mental resilience, and five out of seven resilience factors, “emotional regulation”, “relationship”, “confidence”, “positive thinking” and “spirituality”, compared to those with more weekly gardening time, showing that the efficacy of the mediating effects may peak at a weekly gardening time of between one to four hours. Home gardening may be an effective way for people living in densely populated cities to interact with nature and build mental resilience during the pandemic.
查看更多>>摘要:? 2021 Elsevier GmbHThe COVID-19 pandemic has produced alterations in the behaviour and psychological health of people, who have had to learn living under uncertain circumstances escaping their control. This situation has been aggravated in those countries applying strict home confinement rules to try bending their epidemic curve. This is the case of Spain, where the stringent lockdown period was extended over three months. This study aimed at proving a research hypothesis whereby living close to Green Infrastructure (GI) during the confinement period was beneficial for mental health. To this end, La Palma (Canary Islands) and Zaragoza (Peninsular Spain) were taken as case studies, since both locations distributed a questionnaire to address citizenry's self-reported mental health under strict lockdown conditions. A spatial statistical analysis of the responses collected by these questionnaires revealed that variables such as stress, anger, medication use, alcohol consumption or visits to the doctor significantly decreased if citizens were close to GI, whereas people having very high expectations of enjoying the city after the confinement were positively correlated to proximity of green areas. Although these outcomes are limited by the inferential capacity of correlation analysis, they point out to a sense of relief derived from having visual contact with vegetated landscapes and feeling stimulated about using them for recreation, aesthetical or sporting purposes. The joint consideration of these psychological gains with the social and environmental benefits provided by GI emphasizes the importance of approaching urban regeneration through the design and implementation of interconnected green spaces.
查看更多>>摘要:? 2022 Elsevier GmbHDomestic gardens constitute important refuges for biodiversity. However, their typical small size mismatches with the larger scales at which species procure resources from urban areas. Consequently, they lack the capacity to enhance biodiversity at these scales. This could be addressed by aggregating garden resources (e.g. vegetation) and increasing garden connectivity. Specifically, this could involve neighbouring householders removing brick walls and fences that segregate gardens and collectively planting vegetation across garden boundaries. Nevertheless, insufficient research has explored 1) how hard surfacing gardens influences native/non-native vegetation presence, which could influence this action's effectiveness 2) the number of householders willing to undertake such action 3) reasons for unwillingness and how this could be resolved. These research gaps were addressed using an online householder questionnaire distributed weekly to the UK ‘followers’ of four Facebook pages from January to December 2014. From a total of 276 respondents, 220 (84 %) had gardens with hard surface and this had a significant negative association with native vegetation presence. Only 7 (3%) presently collectively planted vegetation, but 152 (58 %) expressed future willingness. Desires to retain garden control and privacy predominantly underpinned unwillingness. In order to increase the effectiveness and prevalence of collectively planted vegetation, more stringent planning policy is required to restrict hard surfaced gardens. Moreover, desires for garden control and privacy need to be accommodated. This could be principally achieved by 1) communicating that little control would be lost as a result of this action 2) segregating gardens with hedges, which benefit biodiversity and simultaneously provide privacy.
查看更多>>摘要:? 2021 Elsevier GmbHPollination contributes to both human food security and the reproduction of the majority of wild plant species, but pollinators are facing a rapid decline, a major cause of which is habitat conversion and degradation due to human activities. Urbanization is one of the major types of habitat conversion, but its influence on pollination has been surprisingly mixed, ranging from markedly negative to strongly positive effects. One hypothesis proposed to explain these discrepancies is that pollinator responses to urbanization are highly dependent on the non-urban control habitat, with negative effects when the controls are natural or semi-natural areas but positive when they are intensive agricultural areas. It was also proposed that the pollination response along an agricultural-to-urban gradient is non-linear, with maximum pollination observed at an intermediate level of urbanization due to increased environmental heterogeneity. To test these two hypotheses, we selected a group of 38 sites in a peri-urban area near Paris, France, using a semi-stratified sampling strategy that ensured that all three of the urban, agricultural and semi-natural gradients were maximized. We then estimated pollination using two approaches: we evaluated the pollination success of Lotus corniculatus, a strictly entomogamous self-sterile plant species pollinated mainly by bees, and we measured the species richness of entomogamous and non-entomogamous plants, the difference in their response being expected to relate to the pollination service provided by the overall pollinator community. We found that in our study area, pollination success of L. corniculatus responds positively to the agricultural to urban gradient but not to the semi-natural to urban gradient. The diversity of both entomogamous and non-entomogamous plants is highest at sites surrounded by intermediate proportions of urban and agricultural areas. In addition, high proportions of urban areas have a negative effect on the diversity of non-entomogamous but not entomogamous plant species, suggesting that pollinators are able to partially buffer entomogamous plant species against the negative effect of urban development. Our results show the importance of urban areas in pollination conservation plans and demonstrate that the interaction between different anthropogenic land-use is an important factor for understanding pollination.
查看更多>>摘要:? 2022 Elsevier GmbHNurseries play an important role providing trees for a variety of managed environments including urban forests. The diversity of urban forests and forest restoration projects are influenced by nursery species availability, and as such, there is a need to better understand tree species diversity at nurseries. We collected tree species lists from 75 nurseries throughout New Zealand, which were used to describe species richness (alpha diversity) and to examine similarity in the composition of native and non-native species assemblages among nurseries (beta diversity) at three spatial scales: island, region, city. Together, the nurseries grew 863 species, 174 of which were native to New Zealand, from 312 genera and 130 families. Nurseries grew significantly more non-native species (μ = 63.5, σ = 60.6) than native species on average (μ = 31.7, σ = 22.7) (t = 2.99, df = 48.45, p = 0.004). Beta diversity for native and non-native tree species were only significantly different at the scale of cities or regions, not at the larger scale of islands. Few species were grown in all cities or all regions and the majority of those that were common were native species. In contrast, non-native species dominated the unique species at all spatial scales, (i.e., species uniquely grown in one city, region, or island). By quantifying tree species diversity in New Zealand's nurseries, this research provides a basis to better understand the influence that nurseries have on urban and peri-urban tree diversity, and ultimately how that diversity impacts resilience and the provision of ecosystem services.
查看更多>>摘要:? 2022 Elsevier GmbHIncreasing human populations and rapid urbanization in sub-Saharan Africa have prompted the development and maintenance of urban green infrastructure, including urban trees for sustainability, human wellbeing, liveability and climate resilience. However, there are still insufficient amounts and large inequities in the distribution of trees between and within towns and cities of the Global North and South. In South Africa, urban green space planning and planting are encoded in several policies at national level. However, these policies are rarely translated into specific guides, standards or actions, and consequently disparities in urban trees and green space distribution persist. This study assessed the prevalence of urban trees in domestic gardens in low-cost housing areas (LCHAs) of eight small to medium-sized towns in the Eastern Cape province of South Africa and examined residents’ perceptions in this regard. This was done via surveys with 800 households in old and recently developed LCHAs. The results revealed that most households (52 %) had at least one tree in their yard, with more households in the older neighbourhoods (60 %) reporting having trees than in the newer ones (44 %). Most of the trees (66 %) had been deliberately planted as opposed to natural regeneration. Experience of formal urban tree planting programs was low, but 75 % of residents expressed willingness to participate in the future, preferably in tree planting and maintenance. Urban green spaces and trees cannot be an afterthought in the development of sustainable human settlements, and municipal plans should reflect tangible commitments in this regard. Meeting goals for greener LCHAs requires the involvement of local residents, and for municipal authorities to be receptive to the wishes of residents and willingness to green their residential areas.
查看更多>>摘要:? 2022 The AuthorsOne of the important features of cities is to provide high-quality outdoor environments for various groups of citizens. Although children are frequent users of green spaces, the knowledge and perspectives applied in planning and design of urban green spaces are mostly defined by adults. This results in spaces and practices that may limit the daily lives and creativity of urban children. Promoting child-friendly cities benefits from knowledge produced by children themselves, regarding their perceptions and experiences, as well as ideas and suggestions. This study provides empirical results concerning children's needs and mental images for urban green spaces in two urban areas in two countries (Chengdu, China, and Ruhr Region, Germany). 765 children, ages 8–10 were surveyed through the method of empathy-based stories (MEBS). Participants were asked to use their imagination to write stories according to given scenarios. Our study shows that MEBS can be used to gather meaningful data with children, and that children are an important stakeholder group in urban planning, landscape design and management with an ability to express their diverse needs and preferences towards green spaces. Both designed green spaces (e.g. gardens, parks) and wild nature (e.g. forests, meadows) can offer a range of activities and experiences for children in their everyday lives: opportunities for play, socializing, contact with nature, aesthetic and restorative experiences, learning and exploration. Our findings include indications of children's awareness of the diverse ecosystem services that green spaces provide, as well as of urban sustainability and livability. While we found German and Chinese children to have corresponding needs and expectations regarding urban green spaces and nature, we also found some variation. We suggest that the use of, and experiences in green spaces are linked not only to the landscape but also to conceptual-cultural contexts.
查看更多>>摘要:? 2022 Elsevier GmbHPublic green spaces are becoming crucial components of any sustainable community because of their multiple ecological, economic and sociocultural benefits. More efforts are being directed towards creating livelier spaces. Unfortunately, there is less adequate attention to their long-term upkeep. Both research and practice focus more on design aspects of public spaces and parks than on their management. Realising the importance of management, this research is addressing this recognised gap by providing a comprehensive study of the management process. It draws on previous public spaces and green spaces management literature to define four main management requirements: being responsive to context, setting direction, managing performance and dealing with resources. Guided by the systems approach and sustainability concepts, the management requirements and process are presented in a framework that combines different levels of management with the internal dynamics of the public park. This framework can be a useful tool for researchers, designers, decision-makers and managers.