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1.
Pollinator-friendly plants are often a necessary component of the management of urban ecosystem that aim to reduce the impact of the artificial urban matrix on natural pollinator populations. Nectarivorous bats are neglected components of the urban pollinator community and there is a paucity of assessments on pollinator-friendly plants that may provide urban bats with reliable, year-long resources. Crescentia cujete is a bat-pollinated Bignoniaceae with very distinctive chiropterophilous features that is often used as an ornamental species in tropical urban areas worldwide. Its flowers are large and produce copious amounts of nectar, which accumulates in the flower’s storage-shaped flowers. Thus, the species is a potential bat-friendly urban plant. We assessed the species’ year-round flower emission and nightly nectar production dynamics in a green area in northeastern Brazil, and described the behavior of its floral visitors. C. cujete showed a steady, year-round flowering pattern, with no significant seasonality. Its flowers secreted copious amounts of diluted nectar and were visited exclusively by the Pallas long-tongued bat Glossophaga soricina throughout the night at high visiting frequencies, delivering successive visits to individual flowers spaced by short intervals. Our results suggest overexploitation of floral resources from C. cujete by urban bats. Moreover, its continuous flowering and copious nectar production may become a reliable resource in an artificial environment generally lacking bat-pollinated plants, thus mitigating the effects of food shortage for urban nectar bats. 相似文献
2.
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. 相似文献
3.
Kátia Paula Aleixo Letícia Biral de Faria Milton Groppo Maurício Meirelles do Nascimento Castro Cláudia Inês da Silva 《Urban Forestry & Urban Greening》2014,13(4):689-696
Cities provide resources for the animals that live in them or their surroundings. There has been an increase in the number of ecological studies in urban areas, including interactions between plants and bees. Bees are pollinators that provide a vital ecosystem service to crops and wild plants. We assessed plant community structure in the campus of Universidade de São Paulo in Ribeirão Preto, Brazil, included in the neotropical Atlantic Forest biome, focusing on floristic composition, pollination syndromes, flowering phenology, and spatiotemporal distribution of floral resources for bees. Currently, the city is surrounded by sugar cane plantations. Once a month, from April 2011 to March 2012, we sampled plant species and individuals in bloom in an area with 500 m radius from the bee-rearing facilities of Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP), totaling 78 hectares. We sampled 289 plant species of 73 families; Leguminosae was the richest family. Plants pollinated by bees predominated (67%), followed by plants pollinated by hummingbirds (18%). Melittophilous species flowered throughout the year and, hence, food availability for bees was continuous. The flowering of plant individuals that provided pollen, nectar, and floral oil was seasonal in all vegetation (except for nectar in shrubs), with peaks in resource availability in the transition from the dry to the rainy season, and also in the rainy season. Our results show that the campus is able to maintain bee populations amid a monoculture matrix, acting as a refuge. In addition, it provides a list of several attractive native plants to different pollinator groups, coupled with a phenogram, that can be used in the design and planning of urban areas. 相似文献
4.
Urbanization is one of the most intensive threats to biodiversity worldwide. The rapid sprawl of urban settings often comprises a drastic landscape transformation due to the replacement of natural vegetation by impervious surfaces. However, cities can serve as critical refuges for some native fauna, particularly for pollinators. Here we used citizen data to contrast the structure of hummingbird-plant meta-networks across different greenspaces (natural protected areas, urban parks, urban gardens and street trees areas) in a tropical megacity. We compiled hummingbird-plant visitation records in Mexico City available in two citizen science resources: iNaturalist and eBird. We first determined whether the retrieved dataset was representative to estimate network metrics by calculating sample coverage and estimating species richness in different greenspaces. Then, we characterized network structure and plant importance for network organization according to plant origin, life form and pollination syndrome. We recorded 17 hummingbirds visiting 84 plant species, encompassing a total of 742 interactions. Natural protected areas and urban parks showed a higher richness of hummingbirds and plants. All networks had low levels of connectance, specialization, and nestedness. Modularity was significant across all networks with higher values in natural protected areas and urban gardens. Native and introduced plant species showed a similar contribution to network organization. Non-ornithophilous plants were most important in natural protected areas, while tree species were most important in street trees greenspaces. Our results provide evidence of generalization of hummingbird-plant networks in urban areas. Introduced species and non-ornithophilous plants were equally important for hummingbirds, suggesting an integration of alien plants with no specialized bird pollination traits into ecological networks in urban scenarios. Promoting conservation initiatives as pollinator gardens with key native species for hummingbirds across the city could contribute to the functional connectivity and restoration of ecological interactions in cities. 相似文献
5.
Urban green areas, due to their high plant diversity, can be supportive as floral resources (nectar and/or pollen) to wild and managed pollinating insects. This research aims towards understanding the contribution of ornamental ground cover perennials as a food source for urban pollinators. We compare floral phenology and abundance, nectar and pollen production, and insect visitation to flowers of Geranium macrorrhizum, G. platypetalum and G. sanguineum, planted in the botanical garden of Lublin, SE Poland. The investigation revealed that the studied hardy geraniums exhibit many features valuable for pollinators, including large floral display (G. macrorrhizum and G. platypetalum), extended flowering period (G. sanguineum) and ample nectar and pollen reward (G. macrorrhizum). They can supply urban pollinators with a high quality food during spring and early summer time, i.e. the period of high food demand by many bee species. Moreover, hardy geraniums might be valuable plants for urban beekeeping as they are eagerly visited by honeybees. The investigated ground cover plants could therefore be considered in future city plantings. 相似文献
6.
Street trees integrate the urban green infrastructure and are important elements for the maintenance of biodiversity, including pollinators. Thus, assessments of the spatiotemporal distribution and composition of these trees can subsidize strategies of conservation for different groups of pollinators in the cities. Here, we evaluated the spatiotemporal distribution of trees attractive to pollinators across the streetscape of a large Brazilian metropolis with more than 2.5 million inhabitants. We used the georeferenced data of ca. 300,000 woody plant individuals cataloged across the streetscape. These plants were characterized according to their geographical origin, flowering season, and the floral visitor groups that are attracted based on a literature survey. We also tested the “luxury effect” hypothesis on the resource availability to pollinators by evaluating the relationship between the average family income of the population and the richness and abundance of trees. We found that the streetscape was characterized by the dominance of a few tree species, with a balanced representation of both native and non-native species. Bees were the most favored group (94.86%) while bats (1.43%) and moths (1.73%) were the least. The potential supply of resources was homogeneous across dry and wet seasons, but the density of trees was reduced in most of the landscape. We found a strong luxury effect since tree richness and abundance were positively related to regions with higher average family income. Our study highlights the need for better planning and management practices of urban green areas to support pollinators more uniformly across streetscapes. This will allow the benefits provided by pollinators to be more evenly shared among residents of urban landscapes. 相似文献
7.
Urban green areas can play a crucial role in establishing spaces that are valuable for pollinators. However, to help ‘pollinator-friendly’ management of urban areas, complete information on the quantity and quality of available floral reward is needed. In this paper, the nectar and pollen of six Cotoneaster species (Rosaceae) were investigated in a two-year experiment established in Lublin city, SE Poland. In temperate climate, Cotoneaster species can ensure nectar and pollen in the full spring period (May/early June) or in early summer (June). A single species can support pollinators on average for 22.9 days. Flowers of Cotoneaster species produce high quantities of nectar (2.27–9.48 mg per flower) and low amounts of pollen (0.11–0.33 mg per flower). On average, the total sugar yield in Cotoneaster species was 11.5 g/m2 (2.3–22.2 g/m2), whereas the total pollen yield was 1.3 g/m2 (0.8–2.8 g/m2). Due to the high potential for total sugar yield, C. macrophyllus, C. lucidus, and C. horizontalis should be recommended to optimize the management of food resources in urban areas. Honeybee was the main insect visitor (70.1 % of the total number of visitors); therefore, Cotoneaster species can be considered valuable for urban beekeepers. However, conservation schemes for bumblebees (21.3 % of the total number of visitors) might also benefit from arrangements with these shrubs. Nevertheless, considering Cotoneaster species in conservation protocols, good-yielding pollen plants should be introduced to compensate for insufficient nutrient intake from pollen in spring. 相似文献
8.
Pollination is a key ecological service for human food security and the reproduction of the majority of flowering plants. This plant-animal interaction is crucial in both wild and urban habitats, however, increasing urbanization and change in land use alter these interactions. The concerns regarding pollination have led to numerous efforts aimed at improving the quality of wildlife in cities, however, understanding the importance of these activities warrants further research. In Warsaw, the Polish capital, we analyzed the influence of urban-related factors such as floral resource richness, the proportion of green areas in the proximity of foraging sites, air pollution or temperature on plant-pollinator interaction in 14 meadows. We also analyzed the reproductive success and the heterospecific pollen transfer in the case of plants growing in the meadows. Our study revealed that the frequency of visits to flowers was related to city-related factors, but the reaction varied among different groups of pollinators. For example, bumblebees were negatively influenced by higher air pollution, while the rest of the flower visitors were not, Syrphidae flies were more frequent flower visitors when the proportion of green area was higher in the buffer of 150 m, while we did not observe this tendency in other groups of flower visitors. Plants growing in Warsaw meadows were frequently visited and effectively pollinated - urban pollinator assemblages seem to provide sufficient pollination services to plants growing in the city. Species-rich communities were not a threat to pollination; we found mostly conspecific pollen grains on the stigmas of the studied plant species. The results of our study show that species-rich communities make a valuable contribution to pollinator conservation. The conservation activities, however, should be adjusted to the target group of pollinators, since different groups of flower visitors respond differently to urban-related factors studied. 相似文献
9.
Introduced tree species represent a substantial component of urban forests in cities all over the world. Yet there is controversy about the further use of introduced tree species. Many practice orientated publications,research papers and governmental websites in the fields of urban planning, urban forestry, and urban ecology argue for planting native species and avoiding introduced species. Such arguments for native-only species selection are also touted by environmental groups and the media. Consequently the debate has sometimes spiralled away from a sensible and rational platform where invasion risks and biodiversity loss are discussed, to a groundless and unreasonable argument where exotic species are generally considered incapable of providing ecosystem services. From a European perspective, we here aim to curate a set of necessary considerations for current and future discussions on native and non-native plant material in sustainable urban development. Using examples from Northern and Central Europe we illustrate that in some regions the catalogue of native tree species may be too limited to fulfil ecosystem services and resilience in harsh urban environments. A main message from our line of arguments is that we cannot afford to generally exclude non-native tree species from urban greening. If “native-only” approaches become incorporated in regional, national or international policy documents or legislation there is a risk that urban ecosystem resilience will be compromised, particularly in regions with extreme environmental conditions. Since both invasion risks and sizes of native species pools vary conspicuously at regional to continental scales we also argue to adapt urban policies on using non-native trees to regional contexts. 相似文献
10.
Nurseries 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. 相似文献
11.
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
12.
The rarity of species has multiple facets. Functional rarity is an integrated index that can quantify species’ sparseness and functional traits’ rarity. However, a comprehensive evaluation of various dimensions of functional rarity at different scales in urban ecosystems is under-researched. Here, we addressed two hypotheses: (1) functional rarity will not be consistent with conventional rarity at local and regional scales, and (2) land use types influence the distribution of all forms of functionally rare plants in urban ecosystems. We first selected ten functional traits to quantify the functional rarity components of 170 plant species. Second, we assessed the distribution of functional rarity and all forms of functionally rare plants across seven land use types in the megacity of Tokyo. We found that functional rarity is not consistent with conventional rarity at the local and regional scales. Several native species and two non-native species were functionally distinct and not scarce at the local scale. In addition, natural remnants and anthropogenic habitats could protect functionally rare species in urban ecosystems. We thus argue for incorporating functional rarity in the current biodiversity conservation framework and considering natural remnants and anthropogenic habitats in urban functionally rare species conservation. 相似文献
13.
Gregorio I. Gavier-Pizarro Volker C. Radeloff Susan I. Stewart Cynthia D. Huebner Nicholas S. Keuler 《Landscape Ecology》2010,25(10):1505-1518
Forests throughout the US are invaded by non-native invasive plants. Rural housing may contribute to non-native plant invasions
by introducing plants via landscaping, and by creating habitat conditions favorable for invaders. The objective of this paper
was to test the hypothesis that rural housing is a significant factor explaining the distribution of invasive non-native plants
in temperate forests of the Midwestern US. In the Baraboo Hills, Wisconsin, we sampled 105 plots in forest interiors. We recorded
richness and abundance of the most common invasive non-native plants and measured rural housing, human-caused landscape fragmentation
(e.g. roads and forest edges), forest structure and topography. We used regression analysis to identify the variables more
related to the distribution of non-native invasive plants (best subset and hierarchical partitioning analyses for richness
and abundance and logistic regression for presence/absence of individual species). Housing variables had the strongest association
with richness of non-native invasive plants along with distance to forest edge and elevation, while the number of houses in
a 1 km buffer around each plot was the variable most strongly associated with abundance of non-native invasive plants. Rhamnus cathartica and Lonicera spp. were most strongly associated with rural housing and fragmentation. Berberis thumbergii and Rosa multiflora were associated with gentle slopes and low elevation, while Alliaria petiolata was associated with higher cover of native vegetation and stands with no recent logging history. Housing development inside
or adjacent to forests of high conservation value and the use of non-native invasive plants for landscaping should be discouraged. 相似文献
14.
15.
Cities around the world are investing in urban forest plantings as a form of green infrastructure. The aim is that these plantations will develop into naturally-regenerating native forest stands. However, woody plant recruitment is often cited as the most limiting factor to creating self-sustaining urban forests. As such, there is interest in site treatments that promote recruitment of native woody species and simultaneously suppress woody non-native recruitment. We tested how three, common site treatments—compost, nurse shrubs, and tree species composition (six-species vs. two-species)—affected woody plant recruitment in 54 experimental plots beneath a large-scale tree planting within a high-traffic urban park. We identified naturally regenerating seedling and sapling species and measured their abundance six-years after the site was planted. This enabled us to examine initial recruitment dynamics (i.e. seedlings) and gain a better understanding of seedling success as they transition to the midstory (i.e. saplings). Seedling and sapling recruitment (native and total) was greater in areas with higher canopy cover. The combination of the nurse shrub treatment with compost and species composition (six-species) treatments increased seedling recruitment by 47% and 156%, respectively; however, the nurse shrub treatment by itself decreased seedling recruitment by 5% and native seedling recruitment by 35%. The compost treatment alone had no effect on the total number of recruits but resulted in 76% more non-native seedlings. The sizes of these treatment effects were strongly dependent on whether the forest plantings were in open areas, versus areas with existing tree canopy, the latter condition facilitating recruitment. Our findings therefore suggest that combinations of site treatments, paired with broad canopy tree species, may be most effective for promoting regeneration of native species resulting in more self-sustaining urban forests. 相似文献
16.
Pablo González-Moreno Joan Pino David Carreras Corina Basnou Iván Fernández-Rebollar Montserrat Vilà 《Landscape Ecology》2013,28(5):891-903
Landscape pattern might be an important determinant of non-native plant invasions because it encompasses components influencing the availability of non-native plant propagules and disturbance regimes. We aimed at exploring the relative role of patch and landscape characteristics, compared to those of habitat type and regional human influence on non-native plant species richness. For this purpose, we identified all non-native plant species in 295 patches of four coastal habitat types across three administrative regions in NE Spain differing in the degree of human influence. For each patch, we calculated several variables reflecting habitat patch geometry (size and shape), landscape composition (distribution of land-cover categories) and landscape configuration (arrangement of patches). The last two groups of variables were calculated at five different spatial extents. Landscape composition was by far the most important group of variables associated with non-native species richness. Natural areas close to diverse and urban landscapes had a high number of non-native species while surrounding agricultural areas could buffer this effect. Regional human influence was also strongly associated with non-native species richness while habitat type was the least important factor. Differences in sensitivity of landscape variables across spatial extents proved relevant, with 100 m being the most influential extent for most variables. These results suggest that landscape characteristics should be considered for performing explicit spatial risk analyses of plant invasions. Consequently, the management of invaded habitats should focus not only at the stand scale but also at the highly influential neighbouring landscape. Prior to incorporate landscape characteristics into management decisions, sensitivity analyses should be taken into account to avoid inconsistent variables. 相似文献
17.
L. A. Sanchez A. Picado M. J. Sommeijer E. J. Slaa 《The Journal of Horticultural Science and Biotechnology》2013,88(4):498-501
SummaryIn this paper, the floral biology and pollination ecology of Salvia splendens are described. All flower characteristics (red corolla, large tubular flowers with abundant but dilute nectar) indicate that S. splendens is adapted to hummingbird pollination. Honeybees, however, were also found to be good pollinators of this plant. Apis mellifera was equally effective in pollinating S. splendens as hand pollination and open pollination, resulting in a 300% increase in seed set compared with bagged control plants. The much smaller stingless bee Tetragonisca angustula was not an effective pollinator of these flowers since during visitation its body failed to touch the stigma. Although pollination seemed not to be the only limiting factor in seed production, external pollinators enhance seed production in S. splendens, and Apis mellifera is an effective, commercially available pollination agent of this economically important ornamental plant. 相似文献
18.
研究了河南女贞属野生植物及栽培植物9种2变种。根据其资源价值的不同,分为园林观赏物种、中草药、蜜粉源等,并在合理利用与保护女贞属植物资源方面提出一些建设性意见。 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.
With accelerating urbanization, insect pollinators in urban ecosystems face challenges such as reduced pollen sources, habitat fragmentation, and damage to the nesting environment. Urban green spaces (UGS) are essential for the stability of pollinator communities. However, little is known about the relationship between vertical layer heterogeneity and horizontal layer complexity of vegetation structure in UGS and pollinator communities. The present study aimed to assess how vegetation structure and environmental characteristics shape the insect pollinator community in UGS. To this end, this study was conducted with seven typical vegetation types which were selected according to the biotope mapping classification system (BMCS) in the ring parks around Hefei City, in Anhui province, China. A total of 11,401 pollinators belonging to 6 orders and 34 families were identified during the eight-month survey. Among the seven habitats under the BMCS, mainly successional short-cut shrub and partly open green space, trees two- or multi-layered broad-leaved mixed forest and partly closed green space, and mainly successional tall grass and partly open green space were identified as high-quality insect pollinator habitats. According to the results of the generalized linear regression, the explanatory power of the four best-fitting generalised linear models is relatively high (over 77%). In four optimal models, the effect of vegetation structure on pollinator community was greater than that of environmental characteristics. The redundancy discriminant analysis showed that the flowering abundance of nectar plants, herb richness, and shrub coverage rate were the three most important factors influencing insect pollinator communities, with a cumulative explanatory power of up to 78.8%. Pollinator abundance was positively influenced by spontaneous herbs and low-intensity management. However, high-intensity management, low diversity of plants, low nectar plant richness, ignoring seasonal nectar plant configuration, and dense tree distribution could limit pollinator reproduction and population growth. These results reflect the status of insect pollinator community in UGS in Hefei city and present a possible direction for improving urban green habitats and plant configurations. 相似文献