RFID-plants in the smart city: Applications and outlook for urban green management

A city may become smart and green through strategic deployment of Information and Communication Technology infrastructure and services to achieve sustainability policy objectives in which trees have to be involved. Plants not only constitute green space useful to contrast urban pollution effects or provide ecosystemic benefits to residents but they can also be used as bioindicators and their involvement in communication networks can represent a significant contribution to build a smart, green city. The concept of the Internet of Things (IoT) envisages that objects that surround us will be connected and there are no reasons to exclude urban trees from among the “wired object”. Radio frequency identification devices (RFID) may represent a prerequisite of IoT application and they can be used for tree protection and management, thanks to tagging experience carried out on various plant species. RFID tags can be easily associated with plants, externally or internally. This latter approach is particularly indicated if the identification of trees needs to be secured since its production, eliminating the risk of tag losses or removal. Interesting applications may be derived by implementing RFID tags in biomonitoring systems in order to guarantee a real-time data communication in which tags may act as antennas for multifunctional green spaces. Moreover, the virtualization of green areas using sensors and mobile devices can lead to the desktop management of the urban green with the possibility of implementing a real-time navigation throughout the areas. A complex relational network in which data can be collected thanks to geospatial methods can be integrated by an IoT approach in which RFID-plants can play a significant role.     

南昌市园林树种规划及个性化植物景观的营造策略

在对南昌市园林树种应用现状进行调查、分析的基础上,提出南昌市树种规划的原则,就南昌市主城区的基调树种、骨干树种和一般树种等规划内容进行探讨,并提出南昌市个性化植物景观的营造策略。     

Bird-flower interactions in an urban area: Ceiba pubiflora provides nectar and promotes biodiversity in the city

Urbanization has negative effects on plant-animal interactions by reducing plant richness and increasing resource limitations. However, it is possible to replant these areas, and plant species can be selected based on the resources they provide, as well as their relationships with animals. I observed several trees of Ceiba pubiflora (Malvaceae, Bombacoideae) to identify the bird species interacting with their flowers in an urban area. This plant may be especially important, as it blossoms during the dry season, when the overall flower availability in the study area is low. It may also be important during a short period of decline in the fleshy fruit supply. Even though C. pubiflora was growing in the city and had a low volume of nectar accumulating in its flowers (mean of 1.73 μl; SD = 1.39 μl), it attracted a variety of birds (25 species belonging to six families), some of which are usually regarded as forest dependent. Nectarivorous birds from the family Trochilidae (hummingbirds, n = 12 species) had the highest percentage of visits (64.08%), especially during periods of relatively high nectar sugar concentration and calorie availability (c. 18% and 1.5 cal., respectively). Hummingbirds primarily acted as nectar thieves but also sometimes as potential flower pollinators. In contrast, several nonnectarivorous birds (frugivore-granivores, frugivore-insectivores and omnivores) acted only as nectar robbers or flower predators. Ceiba pubiflora flowers appear to be an important source of energy for birds in the urban area. The data of this study show that C. pubiflora has utility as management tool to promote and conserve biodiversity in cities.     

Baobab fruiting is driven by scale-dependent mediation of plant size and landscape features

Landscape Ecology - Both plant size and distribution of plants and resources across landscapes are known to influence pollinator behavior and resulting plant reproductive success. However,...     

Abundance of urban male mosquitoes by green infrastructure types: implications for landscape design and vector management

Context

Urban green space (UGS) is widely espoused in sustainable urban design. Notwithstanding its ecosystem services, UGS is commonly perceived as inadvertent habitats for urban mosquitoes. Moreover, the lack of ecological understanding of mosquitoes and their urban habitats renders vector control in green spaces without reliance on chemical and bio-pesticides especially challenging.

Objectives

This study envisages the application of a comparative analytical method for the evaluation and optimization of vector management in different urban spaces. The research examines the extent of male habitat preference as measured by population characteristics of urban adult mosquitoes on green roof and control sites.

Methods

Adult mosquito traps were deployed on green roofs (GR), bare roofs (negative control, NC), and low-elevation gardens (positive control, PC). Distribution of male and female members of vector species were analyzed

Results

Urban adult male mosquitoes exhibited highly-selective habitat use of the studied urban spaces, in that they were clustered chiefly in PC. Their spatial distributions are consistently explained by site group even under the stringent measure of presence/absence. The sex ratios of GR and NC were highly skewed toward females, which lends further to the interpretation of strong male habitat preference for the studied PC gardens.

Conclusions

Urban mosquitoes do not display similar degrees of affinity for different types of green infrastructure. The methodology used can help prioritize urban sites and optimize control strategies. The uses of amenable environmental features salient to mosquito survival in landscape design should be explored as a sustainable and environmentally-friendly vector management approach.

     

Pond density as a determinant of aquatic species richness in an urban landscape

Green spaces within urban areas provide services and benefits to human populations and habitat for a variety of species. Freshwater, in the form of rivers, canals, lakes, reservoirs and ponds, is an important component of urban greenspaces. This paper focuses on ponds; and specifically ponds within urban areas. This work is timely as during 2008 ponds were designated, in the UK, as habitats of national conservation importance. Yet, while farmland ponds have received considerable attention, there has been little work on the ecology and landscape ecology of urban ponds. Ecological data was collected from 37 ponds in the Borough of Halton (northwest England) over a period of 2 years (2005–2006). The median species richness in these ponds was 28 invertebrate species and 10 macrophyte species. A highly significant correlation was observed between pond density and species richness. The relationship between the richness of different taxa varied according to scale; becoming more significant within pond clusters than within a single pond. These findings have significance for those involved in planning and managing urban environments, further strengthening the need for functional ecological connectivity in urban areas. With pressure to increase infill development, and thus raise housing density, a greater understanding of the affect of urban design on pond ecology will be of importance to urban planners and ecologists alike.     

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.     

Habitat heterogeneity and life-history traits influence presettlement distributions of early-successional tree species in a late-successional, hemlock-hardwood landscape

In landscapes dominated by late-successional plant communities, early-successional species may lead a tenuous existence, persisting only as fugitives or relying on refuges in marginal habitats to provide a persistent seed source. The objective of this study was to relate fine-scale distributions of early-successional tree species in hemlock-hardwood forests of northern Wisconsin, USA to potential landscape persistence strategies. A special emphasis was placed on eastern white pine (Pinus strobus), a restoration priority in the region. Witness tree data from nineteenth century US Public Land Survey records (encompassing 40,610?km² and 106,790 trees) were used with modern environmental data to relate species distributions to habitat characteristics. Early-successional tree species had strong positive associations with marginal habitats such as inclusions of sandy soil and margins of lakes, wetlands, and rivers. Marginal habitats occupied ~44 % of the landscape, which may help account for the abundance of early-successional species in our study area relative to other hemlock-hardwood forests. Populations of early-successional species in marginal habitats could also have provided important seed sources for the upland mesic landscape matrix, as >70 % of the landscape was within 200?m of these habitats. The degree to which early-successional species were limited to marginal habitats largely followed predictions based on species life-history characteristics, except that white pine was more common than expected in upland mesic habitats. These findings illustrate the potential importance of landscape heterogeneity for persistence of early-successional species in late-successional forest landscapes and provide baseline information on habitat associations and landscape dynamics that will be useful in restoration efforts.     

Blowing litter across a landscape: effects on ecosystem nutrient flux and implications for landscape management

Lateral flows in landscape mosaics represent a fundamentally important process in landscape ecology, but are still poorly understood in general. For example, windblown litter nutrient transfer across a landscape has rarely been studied from an ecosystem perspective. In this study we measured the litter nutrient transfer from an Acacia mangium plantation to a Dimocarpus longan orchard in an agroforestry landscape for 3 years from January 2002 to December 2004. About 11% of the total litterfall of the acacia plantation were transported to the longan orchard annually, accounting for ca. 9–59% of the total litter nutrient input of the longan orchard. The windblown litter transfer showed high spatial variation mainly caused by wind speed and directions. Slope positions 5 m away from the source acacia plantation received significantly greater amount of allochthonous acacia litter than those 10 m away, and the northwest-facing slope of the longan orchard received 2 to 3-fold more litter than the southeast- and south-facing slopes because of the prevailing southeasterly wind in the region. To explore how different management practices may influence the litterfall, leaf production, and soil nutrient status of the two ecosystems, we developed a Meta-Ecosystem Litter Transfer (MELT) model to simulate the processes of litter-related transformation (production, deposition, and decomposition) and transfer (wind- and management-driven movement). Our simulation results suggest that less than 30% of acacia litter should be transferred to the longan orchard in order for the acacia plantation to sustain itself and maximize production of the longan. Connectivity of nutrient flow between adjacent ecosystems as shown here leads to a functional meta-ecosystem with higher landscape-scale production of ecosystem services. That is, managing this connectivity through landscape design or active litter transfers can lead to large changes in overall landscape functioning and service production.     

A comparison of metrics predicting landscape connectivity for a highly interactive species along an urban gradient in Colorado, USA

Many organisms persist in fragmented habitat where movement between patches is essential for long-term demographic and genetic stability. In the absence of direct observation of movement, connectivity or isolation metrics are useful to characterize potential patch-level connectivity. However, multiple metrics exist at varying levels of complexity, and empirical data on species distribution are rarely used to compare performance of metrics. We compared 12 connectivity metrics of varying degrees of complexity to determine which metric best predicts the distribution of prairie dog colonies along an urban gradient of 385 isolated habitat patches in Denver, Colorado, USA. We found that a modified version of the incidence function model including area-weighting of patches and a cost-weighted distance surface best predicted occupancy, where we assumed roads were fairly impermeable to movement, and low-lying drainages provided dispersal corridors. We also found this result to be robust to a range of cost weight parameters. Our results suggest that metrics should incorporate both patch area and the composition of the surrounding matrix. These results provide guidance for improved landscape habitat modeling in fragmented landscapes and can help identify target habitat for conservation and management of prairie dogs in urban systems.     

Responses of four hornet species to levels of urban greenness in Nagoya city,Japan: Implications for ecosystem disservices of urban green spaces

Although there is a common trend towards increasing green space in modern cities, urban green spaces provide not only ecosystem services but also disservices for urban dwellers. However, the relationship between urban greenness and ecosystem disservices has been poorly examined. We aimed to understand the effect of greenness level on the abundance and species composition of hornets – critical pests in Japan and to identify the best spatial scale for estimating their abundance with reference to greenness levels. We used a dataset that contained eight years of abundance data for four hornet species at 11 sites in Nagoya city. The levels of greenness around the hornet sampling points were measured using averages from the Normalized Difference Vegetation Index (NDVI) with radiuses of 0.1–10.0 km. We analysed the relationship between abundance and species composition of hornets and NDVI at different spatial scales using generalized linear mixed models. Higher NDVI values positively affected the abundance of all the hornet species except Vespa analis. The abundances were estimated most effectively using the NDVI average with a 1–2 km radius for all species. The species composition of hornets drastically changed along the gradient of NDVI values; V. mandarinia was dominant in greener areas (over 0.2–0.3 NDVI average with a 2 km radius) and V. analis in less green areas (below 0.2–0.3 NDVI average). Our study showed that the abundance and species composition of hornets were both strongly associated with the level of urban greenness. This suggests that increases in the greenness of urban areas can increase hornet abundance and alter the species composition of hornets; a more aggressive species, V. mandarinia, may also increase in urban areas, although V. analis is currently the most critical species according to regional consultants. Balancing ecosystem services and disservices has become crucial for the planning and management of green spaces, particularly when urban green space increases. We also demonstrate how human tolerance towards wildlife may have to be improved in order to live in greener environment where wildlife can be expected.     

Environmental drivers of community diversity in a neotropical urban landscape: a multi-scale analysis

Context

Many aquatic communities are linked by the aerial dispersal of multiple, interacting species and are thus structured by processes occurring in both the aquatic and terrestrial compartments of the ecosystem.

Objectives

To evaluate the environmental factors shaping the aquatic macroinvertebrate communities associated with tank bromeliads in an urban landscape.

Methods

Thirty-two bromeliads were georeferenced to assess the spatial distribution of the aquatic meta-habitat in one city. The relative influence of the aquatic and terrestrial habitats on the structure of macroinvertebrate communities was analyzed at four spatial scales (radius = 10, 30, 50, and 70 m) using redundancy analyses.

Results

We sorted 18,352 aquatic macroinvertebrates into 29 taxa. Water volume and the amount of organic matter explained a significant part of the taxa variance, regardless of spatial scale. The remaining variance was explained by the meta-habitat size (i.e., the water volume for all of the bromeliads within a given surface area), the distance to the nearest building at small scales, and the surface area of buildings plus ground cover at larger scales. At small scales, the meta-habitat size influenced the two most frequent mosquito species in opposite ways, suggesting spatial competition and coexistence. Greater vegetation cover favored the presence of a top predator.

Conclusions

The size of the meta-habitat and urban landscape characteristics influence the structure of aquatic communities in tank bromeliads, including mosquito larval abundance. Modifications to this landscape will affect both the terrestrial and aquatic compartments of the urban ecosystem, offering prospects for mosquito management during urban planning.

     

How different ethno-cultural groups value urban forests and its implications for managing urban nature in a multicultural landscape: A systematic review of the literature

Understanding how different ethno-cultural groups value urban nature is important to understand the role of ethno-cultural diversity in urban ecosystem management. Based on a systematic literature review, this paper summarizes the empirical evidence on how different ethno-cultural groups use, perceive, prefer, and assign meaning to urban nature. I use the urban forest, defined here as all the trees in a city, as a proxy to understand this process. The 31 studies reviewed here differ widely in their lines of inquiry, research methods, urban natural setting, and conceptualizations of ethno-cultural identity. Most studies take place in the US and Europe, where the most common definition of an ethno-culturally diverse group is a person of non-European/non-White background. Most studies focus on what these groups like about a particular urban natural setting, such as an urban park; and whether they like more or less trees in a specific context (e.g. urban park). These groups usually prefer passive and social uses of urban natural areas, and more manicured/functional natural landscapes with less trees. The most common meanings associated with urban natural settings dominated by trees are social interaction and integration. The most common explanations on why these differences occur involve theories on socio-economic marginality, collectivist vs. individualist cultures, urban vs. rural lifestyles, and landscapes of origin. Future research on the topic will benefit by differentiating race from ethnicity, capturing intra-ethnic variation, capturing immigrant identities, exploring the different social, cultural, and economic factors that influence values and/or preferences, and focusing on concrete aspects of urban nature, such as urban forests.     

Non-linear effects of landscape on pollination service and plant species richness in a peri-urban territory with urban and agricultural land use

Pollination 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.     

Distribution of three indigenous fern species along a rural–urban gradient in the city of Angers, France

The preservation of wild plants and animals in urban environments can be a good means to meet the demand for natural areas for recreational purposes. However, the impacts of urbanisation on native species distribution are poorly studied. A city environment has high impact on vegetal community dynamics, especially in terms of climate modification, level of perturbationand pattern of dispersion. We chose to study the three indigenous species of the genus Polypodium that are known to grow in a wide range of habitats, including forest and urban environments, and exhibit a priori a strong ability for dispersal. The aim of the study was to evaluate the factors involved in the Polypodium species distribution and to determine whether this distribution was influenced by the rural–urban gradient. The distribution of the three fern species was investigated in the city of Angers (France) at two levels: for a park (urban woodland) and for the whole city. A contrasted distribution of the three Polypodies has been recorded and shows a rural–urban gradient. This can be explained by the ecology of each species and some biological traits. It means that differences in the spatial structure of the city lead to particular patterns of distribution for these plants. Thus, preserved indigenous vegetation may be influenced in its species composition by the surrounding urban development.     

The influence of management history and habitat on plant species richness in a rural hemiboreal landscape,Sweden

We explored patterns of plant species richness at different spatialscales in 14 habitats in a Swedish rural landscape. Effects of physicalconditions, and relationships between species richness and management historyreaching back to the 17^th century were examined, using old cadastralmaps andaerial photographs. The most species-rich habitats were dry open semi-naturalgrasslands, midfield islets and road verges. Alpha diversity (species richnesswithin sites) was highest in habitats on dry substrates (excluding bedrock withsparse pines) and beta diversity (species richness among sites) was highest inmoist to wet habitats. Alpha and beta components of species richness tended tobe inversely related among habitats with similar species richness. Managementhistory influenced diversity patterns. Areas managed as grasslands in the17^th and 18^th century harboured more species than areasoutside the villages. We also found significant relationships between speciesrichness and soil type. Silt proved to be the most species-rich topsoil(10–20 cm) in addition to thin soils top of on green- orlimestone bedrock. The variation in species richness due to local relief orform of thesite also showed significant relationships, where flat surfaces had the highestnumber of species. In contrast, no significant relationship was found betweenspecies richness and aspect. Our study suggests that present-day diversitypatterns are much influenced by management history, and that small habitat,e.g., road verges and midfield islets, are important for maintaining speciesrichness.This revised version was published online in May 2005 with corrections to the Cover Date.     

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.     

A management driven investigation of landscape patterns of northern spotted owl nesting territories in the high Cascades of Oregon

Investigations using available data sought to guide short-term management decisions regarding the needs of northern spotted owl in the high Cascade Mountains of Oregon. Landscape attributes and pattern indices were measured and tested for identification of areas likely to contain northern spotted owl nests. Predictive models indicating planning standards were developed. Most landscape ecological indices were not useful. Results indicate the owl favors landscapes dominated by patches that meet definitions of late seral forest nesting habitat. The owl optimally nests in such patches at least 570 hectares in size. Landscapes with some edges, particularly around nesting habitat patches evidently do not adversely affect the owl, perhaps because they provide prey. Landscapes with extensive edges, particularly between openings and forests not suitable for nesting, are not as likely to be selected. The results are largely consistent with the owl's recovery plans, provide guidance for management, and require refinement through additional research, particularly to better determine home range sizes.