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1.
Mira Kattwinkel Barbara Strauss Robert Biedermann Michael Kleyer 《Landscape Ecology》2009,24(7):929-941
The importance of the spatial as well as the temporal structure of habitat patches for urban biodiversity has been recognised,
but rarely quantified. In dynamic environments the rate of habitat destruction and recreation (i.e. the landscape turnover
rate), the minimum amount of potential habitat, its spatial configuration as well as the environmental conditions determining
habitat quality are crucial factors for species occurrence. We analysed species responses to environmental parameters and
to the spatio-temporal configuration of urban brownfield habitats in a multi-species approach (37 plant and 43 insect species).
Species presence/absence data and soil parameters, site age, vegetation structure and landscape context were recorded by random
stratified sampling at 133 study plots in industrial areas in the city of Bremen (Germany). Based on the field data, we predicted
species occurrences by species distribution models using a multi-model inference approach. Predicted species communities were
driven by successional age both at the scale of a single building lot and at the landscape scale. Minimum average succession
time of brownfield habitats required to support all and especially regionally rare species depended on the proportion of available
open space; the larger the potential habitat area the faster the acceptable turnover. Most plant, grasshopper, and leafhopper
species modelled could be maintained at an intermediate turnover rate (mean age of 10–15 years) and a proportion of open sites
of at least 40%. Our modelling approach provides the opportunity of inferring optimal spatio-temporal landscape configurations
for urban conservation management from patch scale species-environment relationships. The results indicate that urban planning
should incorporate land use dynamics into the management of urban biodiversity.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
2.
Urban areas have increased greatly in recent decades, which has resulted in habitat loss. However, the promotion of urban green spaces could have a profound effect on biodiversity. Traditional fruit orchards are an important land-use type with the potential to host myriad organisms. Our goal was to determine the most important factors that influence orchard biodiversity in the million city of Prague (the capital of the Czech Republic). We used a multitaxon approach to evaluate the effect of orchard restoration in a landscape context. Restoration had a positive impact on species diversity, specifically, the diversity of orthopterans and butterflies. Moreover, landscape context determined the biodiversity of orthopterans, butterflies, and birds but not that of lichens. Our study underlines the importance of both the internal and external structures of traditional fruit orchards for species richness and composition. The results of our study support the restoration of traditional fruit orchards as a suitable management practice for promoting city biodiversity. Furthermore, orchard restoration can improve the attractiveness of suburban areas. Such areas often lack sufficient urban greening. Thus, restoration in these areas can also increase future recreational value. 相似文献
3.
Landscape change is an ongoing process for even the most established landscapes, especially in context to urban intensification and growth. As urbanization increases over the next century, supporting bird species’ populations within urbanizing areas remains an important conservation challenge. Fundamental elements of the biophysical structure of urban environments in which bird species likely respond include tree cover and human infrastructure. We broadly examine how tree cover and urban development structure bird species distributions along the urban-rural gradient across multiple spatial scales. We established a regional sampling design within the Oak Openings Region of northwestern, Ohio, USA, to survey bird species distributions across an extensive urbanization gradient. Through occupancy modeling, we obtained standardized effects of bird species response to local and landscape-scale predictors and found that landscape tree cover influenced the most species, followed by landscape impervious surface, local building density, and local tree cover. We found that responses varied according to habitat affiliation and migratory distance of individual bird species. Distributions of short-distance, edge habitat species located towards the rural end of the gradient were explained primarily by low levels of urbanization and potential vegetative and supplemental resources associated with these areas, while forest species distributions were primarily related to increasing landscape tree cover. Our findings accentuate the importance of scale relative to urbanization and help target where potential actions may arise to benefit bird diversity. Management will likely need to be implemented by municipal governments and agencies to promote tree cover at landscape scale, followed by residential land management education for private landowners. These approaches will be vital in sustaining biodiversity in urbanizing landscapes as urban growth expands over the next century. 相似文献
4.
Natural parks are comprised of preserved forested natural areas that are undergoing natural ecological processes. These areas can offer a refuge for local biodiversity and contribute substantially to ecosystem services in both rural areas with relatively low population densities, as well as high-density urban areas. Forested natural parks located in urban areas should experience more stressful environmental conditions than nearby rural areas, yet we know relatively little about how urbanization impacts tree communities within these important natural habitats. To better understand the impact of urbanization on forests, we investigated the species composition, abundance, and diversity of midstory and canopy trees as well as tree seedlings in urban and rural natural parks in and around Cleveland, Ohio. We found that both urban and rural natural parks have similar tree abundance, but midstory and canopy trees as well as tree seedling communities in the urban natural parks included higher abundances of stress-tolerant species compared to rural parks. In addition, this pattern was driven by changes in native tree species, as we observed low abundance of invasive species. More stress-resistant native species in urban areas include Quercus rubra and Prunus serotina, in contrast to rural natural parks which are dominated by Acer spp. and Fagus grandifolia. Lastly, we show that urban and rural natural parks have similar species diversity within plots, but we found higher variation in community composition among urban natural parks compared to among rural parks. Furthermore, Q. rubra and P. serotina were significantly larger in rural natural parks, indicating that both environmental stress and successional stage could drive compositional differences. Thus, we show that urbanization can have unexpected effects on plant community composition and diversity. Our study refutes the idea that these are degraded habitats, highlights the need to conserve them, and suggests that characterization of local variation in self-assembled urban tree communities will provide the most accurate picture of their management needs and potential ecosystem services. 相似文献
5.
Forest ecosystems are associated with environmental regulation services, such as carbon storage, which is an outstanding service. Carbon fluxes in cities are difficult to estimate due to the scale at which they are addressed, particularly at the local level. In this work, we were interested in determining the carbon stored in the aboveground biomass of the tropical montane cloud forest tree species located on the western periphery of the city of Xalapa, Veracruz, Mexico. With these data, we interpolated the storage and sequestration over five decades through image satellites and aerial photography of this unique forest. Additionally, to assess this potential as a basis for a biodiversity contribution to city resilience, we conducted phytosociological sampling. Native species such as Quercus xalapensis, Liquidambar styraciflua var. mexicana and Q. lancifolia showed the most significant values of 72.92, 58.79, and 49.14 Mg ha−1, respectively, of carbon. We used phytosociological sampling to better understand structural and functional features of urban forest biodiversity that can contribute to management practices for adaptation to climate change. In addition, the native species currently studied offer an opportunity for the city to implement better-targeted reforestation and ecological restoration programs for integrated landscaping in urban planning. Our results suggest that between 1966 and 2022, there was a forest recovery of 52.4 ha and an increase in urban areas of 63.4 ha, which is equivalent to an increase from 7,700.86 Mg ha−1 in 1966 to 12,620.00 Mg ha−1 in 2022. In this context, it is possible to both recover the vegetation cover and expand the city, thus avoiding part of the loss of ecosystem services that urbanization usually implies. This should be promoted among decision-makers and citizens in urban planning. Recovery processes can take place successfully in some cases even as urban areas expand. This possibility is relevant due to the many contributions that vegetation provides to citizens, including carbon storage. The opportunity to study five decades allows us to know the history, monitor the processes and make a projection to conserve the vegetation and improve management. 相似文献
6.
The Knoxville Urban Wilderness (KUW) in Eastern Tennessee is part of a larger global trend of acquiring vacant lands within urban landscapes for their natural habitat and recreation value. At 688 ha, the KUW is one of the largest urban wilderness areas in the United States, consisting of loosely-connected land parcels with multiple stakeholders including state, county, and city governments and private foundations. Here we use the KUW as a case study to address critical questions of management that arise for most urban wilderness projects globally: What should these areas be managed for, and how should they be managed? How can multiple stakeholders be efficiently organized to pool their resources most effectively. The KUW is currently used mainly for recreation and its potential for biodiversity conservation and education and ecosystem services is largely unutilized. As a way to promote and manage this unused potential, we began the first ecological inventory, compiling existing data and conducting biodiversity and invasive plant surveys with citizen scientists. We found that the KUW harbors a significant number of plant (250) and bird (193) species, with many other taxa also identified. We also found widespread infestation of invasive plants for which we provide management suggestions. A preliminary visitor survey shows that most visitors (about two-thirds) are from the immediate vicinity, mainly for walking (74.4%) or biking (19.9%). The vast majority (93.7%) of visitors do not want more vegetation management or removal and 98.3% of visitors would like to see the KUW expanded in area. 相似文献
7.
In densely urbanized areas, small pockets of vegetated areas such as street verges, vacant lots, and walls can be rich in biodiversity. In spite of their small size, these ‘informal urban greenspaces’ can provide critical ecosystem services to urban residents. Maintaining and enhancing the provisioning of ecosystem services requires a systematic understanding of biodiversity patterns and drivers in informal urban green spaces. The ‘environmental filtering’ (a process of certain species selected by specific environmental conditions) concept in community ecology theory may serve as a useful tool for this goal. We tested a multi-scale filtering framework by examining the spontaneous plant diversity patterns (from 83 surveyed sites) on the vertical surfaces of the ancient city wall of Nanjing, China. We found that the variables representing local-habitat filtering (e.g., wall substrates and aspect) and landscape filtering (including spatial configuration of urban land cover, and nighttime light intensity surrounding the local habitats) can jointly explain substantial fractions of variations in taxonomic diversity (up to ca. 60%) and functional diversity (up to ca. 40%). The explanatory power was stronger in the repaired wall habitats than in the unrepaired counterparts, in line with the prediction that environmental filtering is more pronounced during the early stages of community assembly. While the strength of landscape filtering showed clear scale-dependency, its relative importance consistently outweighs local-habitat filtering across all study scales of 200–1600 m, suggesting that configuration of neighboring landscape context can play an important role in shaping local-scale biodiversity of informal urban green spaces. Our results have useful implications for the study, design, and management of informal urban green spaces. Well-tailored multi-scale filtering frameworks may contribute to understanding urban biodiversity patterns in a systematic way. 相似文献
8.
In arboricultural research, data analysis is important to the understanding of the characteristics of urban forest. This study attempted to apply machine learning techniques on a relatively small data set. This research aimed at exploring the biodiversity and structure of tree stands on verges and slopes along a highway, and analysing the influences of habitat characteristics on the tree stands with the aid of machine learning techniques. 53 slopes and 52 verges along San Tin Highway, Hong Kong were surveyed. 7209 trees belonging to 23 species were found. Dimension reduction proved successful in the concise characterisation of urban forest by a biodiversity component and an abundance component. The biodiversity component score of the slopes (0.625) was higher than that of the verges (−0.637). However, the abundance component scores of slopes (−0.059) and verges (0.060) showed slight difference, reflecting comparable tree abundance. A 75–25 train/test split was applied on a data subset consisting of slopes registered under a scheme called Systematic Identification of Maintenance Responsibility of Slopes in the Territory for regression analysis. The scores of the two components were regressed on several slope geophysical variables. Slope height and slope area served as significant predictors explaining biodiversity. Boosting improved the explanatory power and predictive accuracy of the regression model on the biodiversity component, as evidenced by an increase in adjusted R2 by 0.23 and a decrease in RMSE by 0.40. This research proved that component scores can serve as inputs for regression models for the explanation of urban forest characteristics by habitat-related variables. In future, small data sets from tree surveys can be analysed using the workflow demonstrated in this study for the generation of more management insights. 相似文献
9.
Human preferences for the species in urban greening have greatly facilitated the spread of non-native species, resulting in the homogenization of urban plant communities across spatial scales. We selected 11 major cities along the Yangtze River in China and examined the species composition in their urban plant communities. We found that China’s urban plant communities are becoming homogenized, as urban communities of different cities are highly similar to each other despite the geographical separation. Meanwhile, these artificial communities we investigated have diverged greatly from the natural communities at both the city and the geographic scale. We recorded a total of 91 woody species that have been used in urban greening in all 11 cities. Of those species, 27% were cultivars and introduced species, and 25% were being used outside of their native distribution ranges in China. This may be explained by the market and urban planners who tend to favor greening plants that are highly profitable and have aesthetic ornamental traits, rather than spending time introducing and acclimatizing the native species in each city. Given the current trend of homogenization, measures that recognize the importance of native species should be emphasized with comprehensive urban planning strategies. 相似文献
10.
As the world becomes more urbanized, urban cemeteries may become increasingly valuable for biodiversity conservation as cemeteries are ubiquitous elements of the green infrastructure in cities worldwide. By implementing a multi-taxon approach at different spatial extents, we analyzed habitat functions of a large urban cemetery in Berlin (Weiÿensee Jewish Cemetery) and explored related environmental variables. This cemetery is an outstanding cultural heritage site but it also stands for old urban cemeteries that have progressed to urban woodland, an ecosystem type that exists in many regional and religious contexts. The cemetery provided a habitat for 604 species; species of conservation concern comprised 1.6⿿100% of total species among different groups of taxa (in decreasing order: bats, birds, lichens, bryophytes, carabids, vascular plants, spiders). Species richness and species composition at the plot level were significantly related to differences in management intensity and resulting vegetation structures but differed among taxonomic groups. In vascular plants, carabids and spiders, the species composition varied significantly with habitat age, and there was a set of characteristic species for different age classes in each species group. Our results thus support the use of differentiated management approaches to maintain habitat heterogeneity by allowing wilderness development in some parts of a cemetery while keeping others more open. Since these aims can be combined with efforts to preserve outstanding grave architectures and allow access to visitors, our study indicates ways of reconciling conflicting aims of heritage preservation and biodiversity conservation, a promising perspective for biodiversity conservation in culturally shaped urban landscapes. We conclude that cemeteries provide important cultural ecosystem services within the urban green infrastructure. 相似文献
11.
Cities continue to grow worldwide, and the highly modified urban landscape becomes an inhospitable environment for many species because the natural vegetation cover is commonly fragmented, and the remnants are often isolated. Protected Areas (PAs) located surrounding or within urban areas may not achieve their goal of protecting local or regional biodiversity. Thus, an urban ecological network is essential to support their PAs. Thus, this study aimed at assessing the PAs connectivity in an urban landscape in Brazil and understanding whether urban forest fragments can support an urban ecological network. Besides spatial models based on functional connectivity and graph theory, we used participatory techniques to design the resistance surface and the least-cost paths (LCPs) for Atlantic Forest birds. The results showed critical paths (LCPs), important areas for restoration programs for improving PAs connectivity, and essential forest fragments for conservation and restoration. Although the landscape has a forest structure with 1873 forest fragments and 516 links through which the LCPs were structured, most forest fragments and LCPs cannot provide the necessary support for the PAs connectivity. The current ecological network is dependent on forest fragments neighboring (outside PAs) and the flux dispersions occurred mainly in the peri-urban areas. Riparian zones and anthropic grasslands also showed importance for the PAs connectivity. We identified only 28 forest fragments spatially connected, presenting several sizes, and located near large forest areas, relevant PAs, and riparian zones. Six of these forest fragments, smaller than ten hectares and strategically located in the urban matrix, were indicated for restoration actions. The current low connectivity among PAs brings the importance of native vegetation restoration in the riparian zone and anthropic grassland and the importance of the periurban areas to promote biodiversity connectivity in the urban landscape. 相似文献
12.
Urbanization is a permanent and still continuing expansion of human settlements and is responsible for dramatic changes of natural areas to urban areas. In traditional view, urbanization is often blamed for the loss of biodiversity and biotic homogenization of natural communities. However, for some species, urban areas, can represent suitable environment for life and even enable them to maintain stable and abundant populations. Urban ecosystems are not homogenous; within human settlements we can find several different habitats which can be occupied by species with different tolerance to certain aspects of urban life. This diversity can be exhibited by interhabitat changes in species richness, diversity and abundances of local communities. Here, we investigated biodiversity patterns in bird communities of two urban habitats, parks and cemeteries, in three Central European countries. Data on species richness, diversity and abundances of birds were collected from published papers as well as unpublished sources. Our analyses revealed that bird species richness was positively correlated with area and age of trees in both habitat types. There was however no significant relationship between species diversity and area in both habitat types. Moreover, species composition of bird communities significantly varied between cemeteries and parks with strong preference for one of habitat types in several species. Predominant occupancy of habitat type by certain species could be linked to interhabitat differences in vegetation structure, human behaviour and management. Interestingly, several bird species often recognised as urban avoiders were detected in surveyed cemeteries and parks. 相似文献
13.
Hollow-bearing trees provide habitat for diverse taxonomic groups and as such they are recognised for their importance globally. There is, however scant reference to this resource relative within urban forest patches. The functional ecology of habitat remnants along an urbanisation gradient plays an important ecological, social and economic role within urban landscapes. Here we quantify the impacts of urbanisation, landscape, environmental, disturbance (past and present) and stand variables on hollow-bearing tree density within urban forest patches. This was undertaken by surveying 45 forest patches on the Gold Coast, south-east Queensland, Australia. Sites were categorised as; urban, peri-urban or rural along an urbanisation gradient, with an additional five control sites. Historical logging practices were found to be the driving factor influencing hollow-bearing tree density along the urbanisation gradient; while the impacts of urbanisation itself are not as yet discernible. These findings highlight the significance of incorporating historical land use practise into current and future urban planning, as these will have continuing impacts on remaining urban biodiversity values. These findings, will benefit natural resource managers and urban planners when making decisions about where and how best to manage for hollow-bearing trees along urbanisation gradients. 相似文献
14.
Nearctic-Neotropical migratory birds are threatened by land-use change throughout their complex annual cycles. While urbanization is an essential driver of land-use change, it is unclear how it affects migrant birds. Although migratory birds are more diverse in non-urban patches of native vegetation than in urban areas, neotropical cities can host diverse assemblages of overwintering migrant birds. Migratory birds in neotropical cities tend to be closely associated with urban green areas (UGAs). However, how their presence and abundance are affected by the habitat elements of UGAs and the urban matrix of neotropical cities is poorly understood. In this study, we compared the migratory bird species richness and abundances among UGAs and the urban matrix of the southern section of the megacity of Mexico City and native vegetation sites outside the city. Our results show that UGAs in neotropical cities provide habitats capable of maintaining complex overwintering migratory bird assemblages with local trees as critical features. We also assess the role that UGAs' characteristics play in determining migrant bird assemblages. We conducted bird censuses and measured habitat traits to determine how migrant bird assemblages are related to the habitat features of our study sites. We measured local, buffer, and spatial habitat features of each UGA. We found 23 overwintering migrant species in the three habitats, with 22 present within UGAs. Both UGAs and urban matrix sites had higher estimated species richness of migrant birds than non-urban native vegetation sites located outside the city. Only local features of UGAs affected migrant birds. While tree abundance in UGAs was positively associated with migratory bird species richness, the proportion of tree coverage was positively related to bird abundance. Our results show that UGAs in neotropical cities can maintain complex overwintering migratory bird assemblages, with trees being the most critical habitat feature. As a result, UGA management focused on maintaining trees and increasing their numbers can improve habitat conditions for migratory birds overwintering in neotropical cities. 相似文献
15.
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. 相似文献
16.
Urbanization has been greatly accelerated by the economic growth in China, while its possible effects on woody plants, bird species and their associations are not well defined yet. Here, we analyzed urban-rural gradients (landscape level: urban-farmland-forest-natural reserves; city level: ring road and urban build-up history) and temporal data (1955–1980–2014 for woody plants; 1980s–2010 s for birds) in Harbin city, China, to investigate the changes in the composition and diversity of woody plants and birds during urbanization. Both landscape gradient and temporal data confirmed that urbanization had the function of species conservations with sharp increases of alien species and tropical type plants. In the case woody species, 60-yr urbanization in Harbin had induced increases of 9 families and 17 genera, and there were 7–20 more families, 12–35 more genera, 1.6–2.6 higher Margalef richness in urban areas than those in nature reserves and local forest farms; Increases in alien species (4-fold in 60-yr urbanization; 21% in urban area vs <2% for non-urban region) and tropical type plants (1.6-fold in 60-yr urbanization; temperate/tropical ratio at 1.2 in urban area vs >1.6 in non-urban area) were mainly responsible for these compositional changes, which can be proved by their significant correlations. Moreover, moderate disturbance had peak values in alien species, tropical type plants, Shannon-wiener diversity, Margalef richness index and Pielou evenness index, and both ring road- and buildup history gradients showed the similar tendency. Compared with those in 1980s, forest- and eurytopic-habitats birds increased 9–11 species (23–39%), and omnivorous, insect-eating, and phytophagous bird increased 5–9 species (14.1–29.4%) in those in 2010s, indicating that bird temporal changes were closely related with the changes in urban forests owing to food supply and habitat provision. Our findings could provide data for biodiversity evaluation of urbanization effects, and is also useful for ecological re-construction of local cities in China. 相似文献
17.
The quantity of urban forests in cities is critical for biodiversity conservation and human health, and is known to be distributed unequally. Increasingly, the quality of urban forests are also being recognised as shaping the benefits they provide. Previous studies and reviews have demonstrated that the quality of urban green spaces is associated with patterns of inequality as measured by socio-economic status and race (in the U.S). This study extends this body of knowledge to urban forests by systematically reviewing the urban forest literature (that explicitly study the urban forest) exploring the relationship between urban forest quality and both socio-economic status and race. Two academic databases (SCOPUS and Web of Science) were systematically searched. A total of 2012 papers were screened and 21 articles were included in this study. Almost all studies (20/21) found evidence of inequality, with at least one significant association between measures of urban forest quality and socio-economic status or race. However, 6 studies found contrasting patterns, with lower socioeconomic status areas having higher urban forest quality. There was variation in the type of ‘urban forest’ studied, and variation in the ways both urban forest quality and socio-economic status were measured, making inter-study comparisons difficult. Interestingly, the literature was geographically diverse, and future research could continue to focus on countries in Africa, South America and Asia with diverse needs for and uses of urban forests. In conclusion, this review finds evidence for inequity in the distribution of urban forest quality. Future research that more clearly describes the urban forests being studied and that explores sociocultural variation in perceived quality would allow better generalisation and understanding of forest quality patterns. 相似文献
18.
We applied drone remote sensing to identify relationships between key forest health indicators collected in the field and four Vegetative Indices (VI) to improve conservation management of urban forests. Key indicators of urban forest health revealed several areas of conservation concern including a majority of overstory trees in moderate to severe decline, canopy gaps, anthropogenic dumping, vines overtaking the forest canopy, and invasion by non-native plant species. We found plot-level vegetation index (VI) values of NDVI, NDRE, GNDVI, and GRVI calculated from drone imagery are significantly related to the impact of several of these ecological concerns as well as metrics of forest composition and equitability. Despite the small number of plots, too few to provide a general predictive framework, these findings indicate a substantial potential for drone remote sensing as a low-cost, efficient tool for urban forest management. We discuss how our findings can advance urban forest management and discuss challenges and opportunities for future drone VI research in urban natural areas. 相似文献
19.
The rapid growing urbanization is one of the main threats to urban biodiversity and the ecosystem services (ES) that they provide. Pollination is one of the most affected ES in urban areas mainly due to the decline in urban green areas (UGAs) and other factors derived from urbanization itself. Considering this and the already existing global pollinator crisis, the aim of this work is the evaluation of urban green infrastructure as an opportunity for pollinator conservation. For that purpose, the ornamental vegetation of a medium-sized Mediterranean city (Granada, south-eastern Spain) was determined. The floral origin, phenology and floral traits of the conforming species and the pollinator species that they attract were analysed. Additionally, NMDS analysis were performed in order to determine if the “Pollination Syndromes” are a useful tool to actually predict the pollinator group attracted to a certain plant species. It was found that UGAs have huge potential for pollinator conservation as the major part of its ornamental species have an entomophilic pollination strategy. However, there is an imbalance in the availability of flower resources throughout the year. Hence, the addition of species flowering out of the main flowering season would be advisable in order to get a continuous supply of floral resources for pollinators. A current disproportion in the potentially attracted pollinator groups was also found out, being bees the predominantly attracted ones. However, results showed that the “Pollination Syndromes” are a tool with limitations at the moment and needs to be used with considerations. Thus, the specific plant-pollinator relationship should be determined through field work in each case-study. Further studies considering key factors such as urban connectivity and fragmentation would be desirable to ensure a comprehensive management for urban pollinators. 相似文献
20.
We aimed to assess the impact of land-use structure on AFIS occurrence and evaluation of these bioindicators in urban conditions. We compiled data about forest continuity based on archival maps and forest management plans; floristic records of 79 AFIS occurrences were collected within a 1 × 1 km grid and land-use form structure in Poznań (W Poland). We tested fidelity of AFIS using χ2 tests and effects of land-use structure using random forest models. We also checked spatial autocorrelation and its impact on AFIS distribution patterns within old and recent forests, using spatially explicit generalized linear models. We found a strong relationship between AFIS number per grid square and fraction of forests and waters in land-use structure. Relationships between AFIS distribution and land-use shows that AFIS are a good proxy describing human impact or an urbanity gradient. AFIS number per grid square shows small, but significant positive spatial autocorrelation, which suggests possibilities of migration into new forests. AFIS, treated as a bioindicative group of species, may be a useful indicator of landscape and land-use structure transformation in urban environments. Occurrence of many AFIS that are endangered at the city scale indicates the need for conservation of old forests in urban areas, to preserve biodiversity in urban environments. Thus, AFIS may act as indicators of old forests with high conservation value in cities, which need special protection. 相似文献